/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include "sd-messages.h" #include "af-list.h" #include "alloc-util.h" #include "blockdev-util.h" #include "bpf-devices.h" #include "bpf-firewall.h" #include "bpf-foreign.h" #include "bpf-restrict-ifaces.h" #include "bpf-socket-bind.h" #include "btrfs-util.h" #include "bus-error.h" #include "bus-locator.h" #include "cgroup-setup.h" #include "cgroup-util.h" #include "cgroup.h" #include "devnum-util.h" #include "fd-util.h" #include "fileio.h" #include "firewall-util.h" #include "in-addr-prefix-util.h" #include "inotify-util.h" #include "io-util.h" #include "ip-protocol-list.h" #include "limits-util.h" #include "nulstr-util.h" #include "parse-util.h" #include "path-util.h" #include "percent-util.h" #include "process-util.h" #include "procfs-util.h" #include "set.h" #include "serialize.h" #include "special.h" #include "stdio-util.h" #include "string-table.h" #include "string-util.h" #include "virt.h" #if BPF_FRAMEWORK #include "bpf-dlopen.h" #include "bpf-link.h" #include "bpf/restrict_fs/restrict-fs-skel.h" #endif #define CGROUP_CPU_QUOTA_DEFAULT_PERIOD_USEC ((usec_t) 100 * USEC_PER_MSEC) /* Returns the log level to use when cgroup attribute writes fail. When an attribute is missing or we have access * problems we downgrade to LOG_DEBUG. This is supposed to be nice to container managers and kernels which want to mask * out specific attributes from us. */ #define LOG_LEVEL_CGROUP_WRITE(r) (IN_SET(abs(r), ENOENT, EROFS, EACCES, EPERM) ? LOG_DEBUG : LOG_WARNING) uint64_t cgroup_tasks_max_resolve(const CGroupTasksMax *tasks_max) { if (tasks_max->scale == 0) return tasks_max->value; return system_tasks_max_scale(tasks_max->value, tasks_max->scale); } bool manager_owns_host_root_cgroup(Manager *m) { assert(m); /* Returns true if we are managing the root cgroup. Note that it isn't sufficient to just check whether the * group root path equals "/" since that will also be the case if CLONE_NEWCGROUP is in the mix. Since there's * appears to be no nice way to detect whether we are in a CLONE_NEWCGROUP namespace we instead just check if * we run in any kind of container virtualization. */ if (MANAGER_IS_USER(m)) return false; if (detect_container() > 0) return false; return empty_or_root(m->cgroup_root); } bool unit_has_startup_cgroup_constraints(Unit *u) { assert(u); /* Returns true if this unit has any directives which apply during * startup/shutdown phases. */ CGroupContext *c; c = unit_get_cgroup_context(u); if (!c) return false; return c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID || c->startup_io_weight != CGROUP_WEIGHT_INVALID || c->startup_blockio_weight != CGROUP_BLKIO_WEIGHT_INVALID || c->startup_cpuset_cpus.set || c->startup_cpuset_mems.set || c->startup_memory_high_set || c->startup_memory_max_set || c->startup_memory_swap_max_set|| c->startup_memory_zswap_max_set || c->startup_memory_low_set; } bool unit_has_host_root_cgroup(const Unit *u) { assert(u); assert(u->manager); /* Returns whether this unit manages the root cgroup. This will return true if this unit is the root slice and * the manager manages the root cgroup. */ if (!manager_owns_host_root_cgroup(u->manager)) return false; return unit_has_name(u, SPECIAL_ROOT_SLICE); } static int set_attribute_and_warn(Unit *u, const char *controller, const char *attribute, const char *value) { int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; r = cg_set_attribute(controller, crt->cgroup_path, attribute, value); if (r < 0) log_unit_full_errno(u, LOG_LEVEL_CGROUP_WRITE(r), r, "Failed to set '%s' attribute on '%s' to '%.*s': %m", strna(attribute), empty_to_root(crt->cgroup_path), (int) strcspn(value, NEWLINE), value); return r; } static void cgroup_compat_warn(void) { static bool cgroup_compat_warned = false; if (cgroup_compat_warned) return; log_warning("cgroup compatibility translation between legacy and unified hierarchy settings activated. " "See cgroup-compat debug messages for details."); cgroup_compat_warned = true; } #define log_cgroup_compat(unit, fmt, ...) do { \ cgroup_compat_warn(); \ log_unit_debug(unit, "cgroup-compat: " fmt, ##__VA_ARGS__); \ } while (false) void cgroup_context_init(CGroupContext *c) { assert(c); /* Initialize everything to the kernel defaults. When initializing a bool member to 'true', make * sure to serialize in execute-serialize.c using serialize_bool() instead of * serialize_bool_elide(), as sd-executor will initialize here to 'true', but serialize_bool_elide() * skips serialization if the value is 'false' (as that's the common default), so if the value at * runtime is zero it would be lost after deserialization. Same when initializing uint64_t and other * values, update/add a conditional serialization check. This is to minimize the amount of * serialized data that is sent to the sd-executor, so that there is less work to do on the default * cases. */ *c = (CGroupContext) { .cpu_weight = CGROUP_WEIGHT_INVALID, .startup_cpu_weight = CGROUP_WEIGHT_INVALID, .cpu_quota_per_sec_usec = USEC_INFINITY, .cpu_quota_period_usec = USEC_INFINITY, .cpu_shares = CGROUP_CPU_SHARES_INVALID, .startup_cpu_shares = CGROUP_CPU_SHARES_INVALID, .memory_high = CGROUP_LIMIT_MAX, .startup_memory_high = CGROUP_LIMIT_MAX, .memory_max = CGROUP_LIMIT_MAX, .startup_memory_max = CGROUP_LIMIT_MAX, .memory_swap_max = CGROUP_LIMIT_MAX, .startup_memory_swap_max = CGROUP_LIMIT_MAX, .memory_zswap_max = CGROUP_LIMIT_MAX, .startup_memory_zswap_max = CGROUP_LIMIT_MAX, .memory_limit = CGROUP_LIMIT_MAX, .memory_zswap_writeback = true, .io_weight = CGROUP_WEIGHT_INVALID, .startup_io_weight = CGROUP_WEIGHT_INVALID, .blockio_weight = CGROUP_BLKIO_WEIGHT_INVALID, .startup_blockio_weight = CGROUP_BLKIO_WEIGHT_INVALID, .tasks_max = CGROUP_TASKS_MAX_UNSET, .moom_swap = MANAGED_OOM_AUTO, .moom_mem_pressure = MANAGED_OOM_AUTO, .moom_preference = MANAGED_OOM_PREFERENCE_NONE, .memory_pressure_watch = _CGROUP_PRESSURE_WATCH_INVALID, .memory_pressure_threshold_usec = USEC_INFINITY, }; } int cgroup_context_add_io_device_weight_dup(CGroupContext *c, const CGroupIODeviceWeight *w) { _cleanup_free_ CGroupIODeviceWeight *n = NULL; assert(c); assert(w); n = new(CGroupIODeviceWeight, 1); if (!n) return -ENOMEM; *n = (CGroupIODeviceWeight) { .path = strdup(w->path), .weight = w->weight, }; if (!n->path) return -ENOMEM; LIST_PREPEND(device_weights, c->io_device_weights, TAKE_PTR(n)); return 0; } int cgroup_context_add_io_device_limit_dup(CGroupContext *c, const CGroupIODeviceLimit *l) { _cleanup_free_ CGroupIODeviceLimit *n = NULL; assert(c); assert(l); n = new0(CGroupIODeviceLimit, 1); if (!n) return -ENOMEM; n->path = strdup(l->path); if (!n->path) return -ENOMEM; for (CGroupIOLimitType type = 0; type < _CGROUP_IO_LIMIT_TYPE_MAX; type++) n->limits[type] = l->limits[type]; LIST_PREPEND(device_limits, c->io_device_limits, TAKE_PTR(n)); return 0; } int cgroup_context_add_io_device_latency_dup(CGroupContext *c, const CGroupIODeviceLatency *l) { _cleanup_free_ CGroupIODeviceLatency *n = NULL; assert(c); assert(l); n = new(CGroupIODeviceLatency, 1); if (!n) return -ENOMEM; *n = (CGroupIODeviceLatency) { .path = strdup(l->path), .target_usec = l->target_usec, }; if (!n->path) return -ENOMEM; LIST_PREPEND(device_latencies, c->io_device_latencies, TAKE_PTR(n)); return 0; } int cgroup_context_add_block_io_device_weight_dup(CGroupContext *c, const CGroupBlockIODeviceWeight *w) { _cleanup_free_ CGroupBlockIODeviceWeight *n = NULL; assert(c); assert(w); n = new(CGroupBlockIODeviceWeight, 1); if (!n) return -ENOMEM; *n = (CGroupBlockIODeviceWeight) { .path = strdup(w->path), .weight = w->weight, }; if (!n->path) return -ENOMEM; LIST_PREPEND(device_weights, c->blockio_device_weights, TAKE_PTR(n)); return 0; } int cgroup_context_add_block_io_device_bandwidth_dup(CGroupContext *c, const CGroupBlockIODeviceBandwidth *b) { _cleanup_free_ CGroupBlockIODeviceBandwidth *n = NULL; assert(c); assert(b); n = new(CGroupBlockIODeviceBandwidth, 1); if (!n) return -ENOMEM; *n = (CGroupBlockIODeviceBandwidth) { .rbps = b->rbps, .wbps = b->wbps, }; LIST_PREPEND(device_bandwidths, c->blockio_device_bandwidths, TAKE_PTR(n)); return 0; } int cgroup_context_add_device_allow_dup(CGroupContext *c, const CGroupDeviceAllow *a) { _cleanup_free_ CGroupDeviceAllow *n = NULL; assert(c); assert(a); n = new(CGroupDeviceAllow, 1); if (!n) return -ENOMEM; *n = (CGroupDeviceAllow) { .path = strdup(a->path), .permissions = a->permissions, }; if (!n->path) return -ENOMEM; LIST_PREPEND(device_allow, c->device_allow, TAKE_PTR(n)); return 0; } static int cgroup_context_add_socket_bind_item_dup(CGroupContext *c, const CGroupSocketBindItem *i, CGroupSocketBindItem *h) { _cleanup_free_ CGroupSocketBindItem *n = NULL; assert(c); assert(i); n = new(CGroupSocketBindItem, 1); if (!n) return -ENOMEM; *n = (CGroupSocketBindItem) { .address_family = i->address_family, .ip_protocol = i->ip_protocol, .nr_ports = i->nr_ports, .port_min = i->port_min, }; LIST_PREPEND(socket_bind_items, h, TAKE_PTR(n)); return 0; } int cgroup_context_add_socket_bind_item_allow_dup(CGroupContext *c, const CGroupSocketBindItem *i) { return cgroup_context_add_socket_bind_item_dup(c, i, c->socket_bind_allow); } int cgroup_context_add_socket_bind_item_deny_dup(CGroupContext *c, const CGroupSocketBindItem *i) { return cgroup_context_add_socket_bind_item_dup(c, i, c->socket_bind_deny); } int cgroup_context_copy(CGroupContext *dst, const CGroupContext *src) { struct in_addr_prefix *i; char *iface; int r; assert(src); assert(dst); dst->cpu_accounting = src->cpu_accounting; dst->io_accounting = src->io_accounting; dst->blockio_accounting = src->blockio_accounting; dst->memory_accounting = src->memory_accounting; dst->tasks_accounting = src->tasks_accounting; dst->ip_accounting = src->ip_accounting; dst->memory_oom_group = src->memory_oom_group; dst->cpu_weight = src->cpu_weight; dst->startup_cpu_weight = src->startup_cpu_weight; dst->cpu_quota_per_sec_usec = src->cpu_quota_per_sec_usec; dst->cpu_quota_period_usec = src->cpu_quota_period_usec; dst->cpuset_cpus = src->cpuset_cpus; dst->startup_cpuset_cpus = src->startup_cpuset_cpus; dst->cpuset_mems = src->cpuset_mems; dst->startup_cpuset_mems = src->startup_cpuset_mems; dst->io_weight = src->io_weight; dst->startup_io_weight = src->startup_io_weight; LIST_FOREACH_BACKWARDS(device_weights, w, LIST_FIND_TAIL(device_weights, src->io_device_weights)) { r = cgroup_context_add_io_device_weight_dup(dst, w); if (r < 0) return r; } LIST_FOREACH_BACKWARDS(device_limits, l, LIST_FIND_TAIL(device_limits, src->io_device_limits)) { r = cgroup_context_add_io_device_limit_dup(dst, l); if (r < 0) return r; } LIST_FOREACH_BACKWARDS(device_latencies, l, LIST_FIND_TAIL(device_latencies, src->io_device_latencies)) { r = cgroup_context_add_io_device_latency_dup(dst, l); if (r < 0) return r; } dst->default_memory_min = src->default_memory_min; dst->default_memory_low = src->default_memory_low; dst->default_startup_memory_low = src->default_startup_memory_low; dst->memory_min = src->memory_min; dst->memory_low = src->memory_low; dst->startup_memory_low = src->startup_memory_low; dst->memory_high = src->memory_high; dst->startup_memory_high = src->startup_memory_high; dst->memory_max = src->memory_max; dst->startup_memory_max = src->startup_memory_max; dst->memory_swap_max = src->memory_swap_max; dst->startup_memory_swap_max = src->startup_memory_swap_max; dst->memory_zswap_max = src->memory_zswap_max; dst->startup_memory_zswap_max = src->startup_memory_zswap_max; dst->default_memory_min_set = src->default_memory_min_set; dst->default_memory_low_set = src->default_memory_low_set; dst->default_startup_memory_low_set = src->default_startup_memory_low_set; dst->memory_min_set = src->memory_min_set; dst->memory_low_set = src->memory_low_set; dst->startup_memory_low_set = src->startup_memory_low_set; dst->startup_memory_high_set = src->startup_memory_high_set; dst->startup_memory_max_set = src->startup_memory_max_set; dst->startup_memory_swap_max_set = src->startup_memory_swap_max_set; dst->startup_memory_zswap_max_set = src->startup_memory_zswap_max_set; dst->memory_zswap_writeback = src->memory_zswap_writeback; SET_FOREACH(i, src->ip_address_allow) { r = in_addr_prefix_add(&dst->ip_address_allow, i); if (r < 0) return r; } SET_FOREACH(i, src->ip_address_deny) { r = in_addr_prefix_add(&dst->ip_address_deny, i); if (r < 0) return r; } dst->ip_address_allow_reduced = src->ip_address_allow_reduced; dst->ip_address_deny_reduced = src->ip_address_deny_reduced; if (!strv_isempty(src->ip_filters_ingress)) { dst->ip_filters_ingress = strv_copy(src->ip_filters_ingress); if (!dst->ip_filters_ingress) return -ENOMEM; } if (!strv_isempty(src->ip_filters_egress)) { dst->ip_filters_egress = strv_copy(src->ip_filters_egress); if (!dst->ip_filters_egress) return -ENOMEM; } LIST_FOREACH_BACKWARDS(programs, l, LIST_FIND_TAIL(programs, src->bpf_foreign_programs)) { r = cgroup_context_add_bpf_foreign_program_dup(dst, l); if (r < 0) return r; } SET_FOREACH(iface, src->restrict_network_interfaces) { r = set_put_strdup(&dst->restrict_network_interfaces, iface); if (r < 0) return r; } dst->restrict_network_interfaces_is_allow_list = src->restrict_network_interfaces_is_allow_list; dst->cpu_shares = src->cpu_shares; dst->startup_cpu_shares = src->startup_cpu_shares; dst->blockio_weight = src->blockio_weight; dst->startup_blockio_weight = src->startup_blockio_weight; LIST_FOREACH_BACKWARDS(device_weights, l, LIST_FIND_TAIL(device_weights, src->blockio_device_weights)) { r = cgroup_context_add_block_io_device_weight_dup(dst, l); if (r < 0) return r; } LIST_FOREACH_BACKWARDS(device_bandwidths, l, LIST_FIND_TAIL(device_bandwidths, src->blockio_device_bandwidths)) { r = cgroup_context_add_block_io_device_bandwidth_dup(dst, l); if (r < 0) return r; } dst->memory_limit = src->memory_limit; dst->device_policy = src->device_policy; LIST_FOREACH_BACKWARDS(device_allow, l, LIST_FIND_TAIL(device_allow, src->device_allow)) { r = cgroup_context_add_device_allow_dup(dst, l); if (r < 0) return r; } LIST_FOREACH_BACKWARDS(socket_bind_items, l, LIST_FIND_TAIL(socket_bind_items, src->socket_bind_allow)) { r = cgroup_context_add_socket_bind_item_allow_dup(dst, l); if (r < 0) return r; } LIST_FOREACH_BACKWARDS(socket_bind_items, l, LIST_FIND_TAIL(socket_bind_items, src->socket_bind_deny)) { r = cgroup_context_add_socket_bind_item_deny_dup(dst, l); if (r < 0) return r; } dst->tasks_max = src->tasks_max; return 0; } void cgroup_context_free_device_allow(CGroupContext *c, CGroupDeviceAllow *a) { assert(c); assert(a); LIST_REMOVE(device_allow, c->device_allow, a); free(a->path); free(a); } void cgroup_context_free_io_device_weight(CGroupContext *c, CGroupIODeviceWeight *w) { assert(c); assert(w); LIST_REMOVE(device_weights, c->io_device_weights, w); free(w->path); free(w); } void cgroup_context_free_io_device_latency(CGroupContext *c, CGroupIODeviceLatency *l) { assert(c); assert(l); LIST_REMOVE(device_latencies, c->io_device_latencies, l); free(l->path); free(l); } void cgroup_context_free_io_device_limit(CGroupContext *c, CGroupIODeviceLimit *l) { assert(c); assert(l); LIST_REMOVE(device_limits, c->io_device_limits, l); free(l->path); free(l); } void cgroup_context_free_blockio_device_weight(CGroupContext *c, CGroupBlockIODeviceWeight *w) { assert(c); assert(w); LIST_REMOVE(device_weights, c->blockio_device_weights, w); free(w->path); free(w); } void cgroup_context_free_blockio_device_bandwidth(CGroupContext *c, CGroupBlockIODeviceBandwidth *b) { assert(c); assert(b); LIST_REMOVE(device_bandwidths, c->blockio_device_bandwidths, b); free(b->path); free(b); } void cgroup_context_remove_bpf_foreign_program(CGroupContext *c, CGroupBPFForeignProgram *p) { assert(c); assert(p); LIST_REMOVE(programs, c->bpf_foreign_programs, p); free(p->bpffs_path); free(p); } void cgroup_context_remove_socket_bind(CGroupSocketBindItem **head) { assert(head); LIST_CLEAR(socket_bind_items, *head, free); } void cgroup_context_done(CGroupContext *c) { assert(c); while (c->io_device_weights) cgroup_context_free_io_device_weight(c, c->io_device_weights); while (c->io_device_latencies) cgroup_context_free_io_device_latency(c, c->io_device_latencies); while (c->io_device_limits) cgroup_context_free_io_device_limit(c, c->io_device_limits); while (c->blockio_device_weights) cgroup_context_free_blockio_device_weight(c, c->blockio_device_weights); while (c->blockio_device_bandwidths) cgroup_context_free_blockio_device_bandwidth(c, c->blockio_device_bandwidths); while (c->device_allow) cgroup_context_free_device_allow(c, c->device_allow); cgroup_context_remove_socket_bind(&c->socket_bind_allow); cgroup_context_remove_socket_bind(&c->socket_bind_deny); c->ip_address_allow = set_free(c->ip_address_allow); c->ip_address_deny = set_free(c->ip_address_deny); c->ip_filters_ingress = strv_free(c->ip_filters_ingress); c->ip_filters_egress = strv_free(c->ip_filters_egress); while (c->bpf_foreign_programs) cgroup_context_remove_bpf_foreign_program(c, c->bpf_foreign_programs); c->restrict_network_interfaces = set_free_free(c->restrict_network_interfaces); cpu_set_reset(&c->cpuset_cpus); cpu_set_reset(&c->startup_cpuset_cpus); cpu_set_reset(&c->cpuset_mems); cpu_set_reset(&c->startup_cpuset_mems); c->delegate_subgroup = mfree(c->delegate_subgroup); nft_set_context_clear(&c->nft_set_context); } static int unit_get_kernel_memory_limit(Unit *u, const char *file, uint64_t *ret) { assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; return cg_get_attribute_as_uint64("memory", crt->cgroup_path, file, ret); } static int unit_compare_memory_limit(Unit *u, const char *property_name, uint64_t *ret_unit_value, uint64_t *ret_kernel_value) { CGroupContext *c; CGroupMask m; const char *file; uint64_t unit_value; int r; /* Compare kernel memcg configuration against our internal systemd state. Unsupported (and will * return -ENODATA) on cgroup v1. * * Returns: * * <0: On error. * 0: If the kernel memory setting doesn't match our configuration. * >0: If the kernel memory setting matches our configuration. * * The following values are only guaranteed to be populated on return >=0: * * - ret_unit_value will contain our internal expected value for the unit, page-aligned. * - ret_kernel_value will contain the actual value presented by the kernel. */ assert(u); r = cg_all_unified(); if (r < 0) return log_debug_errno(r, "Failed to determine cgroup hierarchy version: %m"); /* Unsupported on v1. * * We don't return ENOENT, since that could actually mask a genuine problem where somebody else has * silently masked the controller. */ if (r == 0) return -ENODATA; /* The root slice doesn't have any controller files, so we can't compare anything. */ if (unit_has_name(u, SPECIAL_ROOT_SLICE)) return -ENODATA; /* It's possible to have MemoryFoo set without systemd wanting to have the memory controller enabled, * for example, in the case of DisableControllers= or cgroup_disable on the kernel command line. To * avoid specious errors in these scenarios, check that we even expect the memory controller to be * enabled at all. */ m = unit_get_target_mask(u); if (!FLAGS_SET(m, CGROUP_MASK_MEMORY)) return -ENODATA; assert_se(c = unit_get_cgroup_context(u)); bool startup = u->manager && IN_SET(manager_state(u->manager), MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING); if (streq(property_name, "MemoryLow")) { unit_value = unit_get_ancestor_memory_low(u); file = "memory.low"; } else if (startup && streq(property_name, "StartupMemoryLow")) { unit_value = unit_get_ancestor_startup_memory_low(u); file = "memory.low"; } else if (streq(property_name, "MemoryMin")) { unit_value = unit_get_ancestor_memory_min(u); file = "memory.min"; } else if (streq(property_name, "MemoryHigh")) { unit_value = c->memory_high; file = "memory.high"; } else if (startup && streq(property_name, "StartupMemoryHigh")) { unit_value = c->startup_memory_high; file = "memory.high"; } else if (streq(property_name, "MemoryMax")) { unit_value = c->memory_max; file = "memory.max"; } else if (startup && streq(property_name, "StartupMemoryMax")) { unit_value = c->startup_memory_max; file = "memory.max"; } else if (streq(property_name, "MemorySwapMax")) { unit_value = c->memory_swap_max; file = "memory.swap.max"; } else if (startup && streq(property_name, "StartupMemorySwapMax")) { unit_value = c->startup_memory_swap_max; file = "memory.swap.max"; } else if (streq(property_name, "MemoryZSwapMax")) { unit_value = c->memory_zswap_max; file = "memory.zswap.max"; } else if (startup && streq(property_name, "StartupMemoryZSwapMax")) { unit_value = c->startup_memory_zswap_max; file = "memory.zswap.max"; } else return -EINVAL; r = unit_get_kernel_memory_limit(u, file, ret_kernel_value); if (r < 0) return log_unit_debug_errno(u, r, "Failed to parse %s: %m", file); /* It's intended (soon) in a future kernel to not expose cgroup memory limits rounded to page * boundaries, but instead separate the user-exposed limit, which is whatever userspace told us, from * our internal page-counting. To support those future kernels, just check the value itself first * without any page-alignment. */ if (*ret_kernel_value == unit_value) { *ret_unit_value = unit_value; return 1; } /* The current kernel behaviour, by comparison, is that even if you write a particular number of * bytes into a cgroup memory file, it always returns that number page-aligned down (since the kernel * internally stores cgroup limits in pages). As such, so long as it aligns properly, everything is * cricket. */ if (unit_value != CGROUP_LIMIT_MAX) unit_value = PAGE_ALIGN_DOWN(unit_value); *ret_unit_value = unit_value; return *ret_kernel_value == *ret_unit_value; } #define FORMAT_CGROUP_DIFF_MAX 128 static char *format_cgroup_memory_limit_comparison(Unit *u, const char *property_name, char *buf, size_t l) { uint64_t kval, sval; int r; assert(u); assert(property_name); assert(buf); assert(l > 0); r = unit_compare_memory_limit(u, property_name, &sval, &kval); /* memory.swap.max is special in that it relies on CONFIG_MEMCG_SWAP (and the default swapaccount=1). * In the absence of reliably being able to detect whether memcg swap support is available or not, * only complain if the error is not ENOENT. This is similarly the case for memory.zswap.max relying * on CONFIG_ZSWAP. */ if (r > 0 || IN_SET(r, -ENODATA, -EOWNERDEAD) || (r == -ENOENT && STR_IN_SET(property_name, "MemorySwapMax", "StartupMemorySwapMax", "MemoryZSwapMax", "StartupMemoryZSwapMax"))) buf[0] = 0; else if (r < 0) { errno = -r; (void) snprintf(buf, l, " (error getting kernel value: %m)"); } else (void) snprintf(buf, l, " (different value in kernel: %" PRIu64 ")", kval); return buf; } const char *cgroup_device_permissions_to_string(CGroupDevicePermissions p) { static const char *table[_CGROUP_DEVICE_PERMISSIONS_MAX] = { /* Lets simply define a table with every possible combination. As long as those are just 8 we * can get away with it. If this ever grows to more we need to revisit this logic though. */ [0] = "", [CGROUP_DEVICE_READ] = "r", [CGROUP_DEVICE_WRITE] = "w", [CGROUP_DEVICE_MKNOD] = "m", [CGROUP_DEVICE_READ|CGROUP_DEVICE_WRITE] = "rw", [CGROUP_DEVICE_READ|CGROUP_DEVICE_MKNOD] = "rm", [CGROUP_DEVICE_WRITE|CGROUP_DEVICE_MKNOD] = "wm", [CGROUP_DEVICE_READ|CGROUP_DEVICE_WRITE|CGROUP_DEVICE_MKNOD] = "rwm", }; if (p < 0 || p >= _CGROUP_DEVICE_PERMISSIONS_MAX) return NULL; return table[p]; } CGroupDevicePermissions cgroup_device_permissions_from_string(const char *s) { CGroupDevicePermissions p = 0; if (!s) return _CGROUP_DEVICE_PERMISSIONS_INVALID; for (const char *c = s; *c; c++) { if (*c == 'r') p |= CGROUP_DEVICE_READ; else if (*c == 'w') p |= CGROUP_DEVICE_WRITE; else if (*c == 'm') p |= CGROUP_DEVICE_MKNOD; else return _CGROUP_DEVICE_PERMISSIONS_INVALID; } return p; } void cgroup_context_dump(Unit *u, FILE* f, const char *prefix) { _cleanup_free_ char *disable_controllers_str = NULL, *delegate_controllers_str = NULL, *cpuset_cpus = NULL, *cpuset_mems = NULL, *startup_cpuset_cpus = NULL, *startup_cpuset_mems = NULL; CGroupContext *c; struct in_addr_prefix *iaai; char cda[FORMAT_CGROUP_DIFF_MAX], cdb[FORMAT_CGROUP_DIFF_MAX], cdc[FORMAT_CGROUP_DIFF_MAX], cdd[FORMAT_CGROUP_DIFF_MAX], cde[FORMAT_CGROUP_DIFF_MAX], cdf[FORMAT_CGROUP_DIFF_MAX], cdg[FORMAT_CGROUP_DIFF_MAX], cdh[FORMAT_CGROUP_DIFF_MAX], cdi[FORMAT_CGROUP_DIFF_MAX], cdj[FORMAT_CGROUP_DIFF_MAX], cdk[FORMAT_CGROUP_DIFF_MAX]; assert(u); assert(f); assert_se(c = unit_get_cgroup_context(u)); prefix = strempty(prefix); (void) cg_mask_to_string(c->disable_controllers, &disable_controllers_str); (void) cg_mask_to_string(c->delegate_controllers, &delegate_controllers_str); /* "Delegate=" means "yes, but no controllers". Show this as "(none)". */ const char *delegate_str = delegate_controllers_str ?: c->delegate ? "(none)" : "no"; cpuset_cpus = cpu_set_to_range_string(&c->cpuset_cpus); startup_cpuset_cpus = cpu_set_to_range_string(&c->startup_cpuset_cpus); cpuset_mems = cpu_set_to_range_string(&c->cpuset_mems); startup_cpuset_mems = cpu_set_to_range_string(&c->startup_cpuset_mems); fprintf(f, "%sCPUAccounting: %s\n" "%sIOAccounting: %s\n" "%sBlockIOAccounting: %s\n" "%sMemoryAccounting: %s\n" "%sTasksAccounting: %s\n" "%sIPAccounting: %s\n" "%sCPUWeight: %" PRIu64 "\n" "%sStartupCPUWeight: %" PRIu64 "\n" "%sCPUShares: %" PRIu64 "\n" "%sStartupCPUShares: %" PRIu64 "\n" "%sCPUQuotaPerSecSec: %s\n" "%sCPUQuotaPeriodSec: %s\n" "%sAllowedCPUs: %s\n" "%sStartupAllowedCPUs: %s\n" "%sAllowedMemoryNodes: %s\n" "%sStartupAllowedMemoryNodes: %s\n" "%sIOWeight: %" PRIu64 "\n" "%sStartupIOWeight: %" PRIu64 "\n" "%sBlockIOWeight: %" PRIu64 "\n" "%sStartupBlockIOWeight: %" PRIu64 "\n" "%sDefaultMemoryMin: %" PRIu64 "\n" "%sDefaultMemoryLow: %" PRIu64 "\n" "%sMemoryMin: %" PRIu64 "%s\n" "%sMemoryLow: %" PRIu64 "%s\n" "%sStartupMemoryLow: %" PRIu64 "%s\n" "%sMemoryHigh: %" PRIu64 "%s\n" "%sStartupMemoryHigh: %" PRIu64 "%s\n" "%sMemoryMax: %" PRIu64 "%s\n" "%sStartupMemoryMax: %" PRIu64 "%s\n" "%sMemorySwapMax: %" PRIu64 "%s\n" "%sStartupMemorySwapMax: %" PRIu64 "%s\n" "%sMemoryZSwapMax: %" PRIu64 "%s\n" "%sStartupMemoryZSwapMax: %" PRIu64 "%s\n" "%sMemoryZSwapWriteback: %s\n" "%sMemoryLimit: %" PRIu64 "\n" "%sTasksMax: %" PRIu64 "\n" "%sDevicePolicy: %s\n" "%sDisableControllers: %s\n" "%sDelegate: %s\n" "%sManagedOOMSwap: %s\n" "%sManagedOOMMemoryPressure: %s\n" "%sManagedOOMMemoryPressureLimit: " PERMYRIAD_AS_PERCENT_FORMAT_STR "\n" "%sManagedOOMPreference: %s\n" "%sMemoryPressureWatch: %s\n" "%sCoredumpReceive: %s\n", prefix, yes_no(c->cpu_accounting), prefix, yes_no(c->io_accounting), prefix, yes_no(c->blockio_accounting), prefix, yes_no(c->memory_accounting), prefix, yes_no(c->tasks_accounting), prefix, yes_no(c->ip_accounting), prefix, c->cpu_weight, prefix, c->startup_cpu_weight, prefix, c->cpu_shares, prefix, c->startup_cpu_shares, prefix, FORMAT_TIMESPAN(c->cpu_quota_per_sec_usec, 1), prefix, FORMAT_TIMESPAN(c->cpu_quota_period_usec, 1), prefix, strempty(cpuset_cpus), prefix, strempty(startup_cpuset_cpus), prefix, strempty(cpuset_mems), prefix, strempty(startup_cpuset_mems), prefix, c->io_weight, prefix, c->startup_io_weight, prefix, c->blockio_weight, prefix, c->startup_blockio_weight, prefix, c->default_memory_min, prefix, c->default_memory_low, prefix, c->memory_min, format_cgroup_memory_limit_comparison(u, "MemoryMin", cda, sizeof(cda)), prefix, c->memory_low, format_cgroup_memory_limit_comparison(u, "MemoryLow", cdb, sizeof(cdb)), prefix, c->startup_memory_low, format_cgroup_memory_limit_comparison(u, "StartupMemoryLow", cdc, sizeof(cdc)), prefix, c->memory_high, format_cgroup_memory_limit_comparison(u, "MemoryHigh", cdd, sizeof(cdd)), prefix, c->startup_memory_high, format_cgroup_memory_limit_comparison(u, "StartupMemoryHigh", cde, sizeof(cde)), prefix, c->memory_max, format_cgroup_memory_limit_comparison(u, "MemoryMax", cdf, sizeof(cdf)), prefix, c->startup_memory_max, format_cgroup_memory_limit_comparison(u, "StartupMemoryMax", cdg, sizeof(cdg)), prefix, c->memory_swap_max, format_cgroup_memory_limit_comparison(u, "MemorySwapMax", cdh, sizeof(cdh)), prefix, c->startup_memory_swap_max, format_cgroup_memory_limit_comparison(u, "StartupMemorySwapMax", cdi, sizeof(cdi)), prefix, c->memory_zswap_max, format_cgroup_memory_limit_comparison(u, "MemoryZSwapMax", cdj, sizeof(cdj)), prefix, c->startup_memory_zswap_max, format_cgroup_memory_limit_comparison(u, "StartupMemoryZSwapMax", cdk, sizeof(cdk)), prefix, yes_no(c->memory_zswap_writeback), prefix, c->memory_limit, prefix, cgroup_tasks_max_resolve(&c->tasks_max), prefix, cgroup_device_policy_to_string(c->device_policy), prefix, strempty(disable_controllers_str), prefix, delegate_str, prefix, managed_oom_mode_to_string(c->moom_swap), prefix, managed_oom_mode_to_string(c->moom_mem_pressure), prefix, PERMYRIAD_AS_PERCENT_FORMAT_VAL(UINT32_SCALE_TO_PERMYRIAD(c->moom_mem_pressure_limit)), prefix, managed_oom_preference_to_string(c->moom_preference), prefix, cgroup_pressure_watch_to_string(c->memory_pressure_watch), prefix, yes_no(c->coredump_receive)); if (c->delegate_subgroup) fprintf(f, "%sDelegateSubgroup: %s\n", prefix, c->delegate_subgroup); if (c->memory_pressure_threshold_usec != USEC_INFINITY) fprintf(f, "%sMemoryPressureThresholdSec: %s\n", prefix, FORMAT_TIMESPAN(c->memory_pressure_threshold_usec, 1)); LIST_FOREACH(device_allow, a, c->device_allow) /* strna() below should be redundant, for avoiding -Werror=format-overflow= error. See #30223. */ fprintf(f, "%sDeviceAllow: %s %s\n", prefix, a->path, strna(cgroup_device_permissions_to_string(a->permissions))); LIST_FOREACH(device_weights, iw, c->io_device_weights) fprintf(f, "%sIODeviceWeight: %s %" PRIu64 "\n", prefix, iw->path, iw->weight); LIST_FOREACH(device_latencies, l, c->io_device_latencies) fprintf(f, "%sIODeviceLatencyTargetSec: %s %s\n", prefix, l->path, FORMAT_TIMESPAN(l->target_usec, 1)); LIST_FOREACH(device_limits, il, c->io_device_limits) for (CGroupIOLimitType type = 0; type < _CGROUP_IO_LIMIT_TYPE_MAX; type++) if (il->limits[type] != cgroup_io_limit_defaults[type]) fprintf(f, "%s%s: %s %s\n", prefix, cgroup_io_limit_type_to_string(type), il->path, FORMAT_BYTES(il->limits[type])); LIST_FOREACH(device_weights, w, c->blockio_device_weights) fprintf(f, "%sBlockIODeviceWeight: %s %" PRIu64, prefix, w->path, w->weight); LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) { if (b->rbps != CGROUP_LIMIT_MAX) fprintf(f, "%sBlockIOReadBandwidth: %s %s\n", prefix, b->path, FORMAT_BYTES(b->rbps)); if (b->wbps != CGROUP_LIMIT_MAX) fprintf(f, "%sBlockIOWriteBandwidth: %s %s\n", prefix, b->path, FORMAT_BYTES(b->wbps)); } SET_FOREACH(iaai, c->ip_address_allow) fprintf(f, "%sIPAddressAllow: %s\n", prefix, IN_ADDR_PREFIX_TO_STRING(iaai->family, &iaai->address, iaai->prefixlen)); SET_FOREACH(iaai, c->ip_address_deny) fprintf(f, "%sIPAddressDeny: %s\n", prefix, IN_ADDR_PREFIX_TO_STRING(iaai->family, &iaai->address, iaai->prefixlen)); STRV_FOREACH(path, c->ip_filters_ingress) fprintf(f, "%sIPIngressFilterPath: %s\n", prefix, *path); STRV_FOREACH(path, c->ip_filters_egress) fprintf(f, "%sIPEgressFilterPath: %s\n", prefix, *path); LIST_FOREACH(programs, p, c->bpf_foreign_programs) fprintf(f, "%sBPFProgram: %s:%s", prefix, bpf_cgroup_attach_type_to_string(p->attach_type), p->bpffs_path); if (c->socket_bind_allow) { fprintf(f, "%sSocketBindAllow: ", prefix); cgroup_context_dump_socket_bind_items(c->socket_bind_allow, f); fputc('\n', f); } if (c->socket_bind_deny) { fprintf(f, "%sSocketBindDeny: ", prefix); cgroup_context_dump_socket_bind_items(c->socket_bind_deny, f); fputc('\n', f); } if (c->restrict_network_interfaces) { char *iface; SET_FOREACH(iface, c->restrict_network_interfaces) fprintf(f, "%sRestrictNetworkInterfaces: %s\n", prefix, iface); } FOREACH_ARRAY(nft_set, c->nft_set_context.sets, c->nft_set_context.n_sets) fprintf(f, "%sNFTSet: %s:%s:%s:%s\n", prefix, nft_set_source_to_string(nft_set->source), nfproto_to_string(nft_set->nfproto), nft_set->table, nft_set->set); } void cgroup_context_dump_socket_bind_item(const CGroupSocketBindItem *item, FILE *f) { const char *family, *colon1, *protocol = "", *colon2 = ""; family = strempty(af_to_ipv4_ipv6(item->address_family)); colon1 = isempty(family) ? "" : ":"; if (item->ip_protocol != 0) { protocol = ip_protocol_to_tcp_udp(item->ip_protocol); colon2 = ":"; } if (item->nr_ports == 0) fprintf(f, "%s%s%s%sany", family, colon1, protocol, colon2); else if (item->nr_ports == 1) fprintf(f, "%s%s%s%s%" PRIu16, family, colon1, protocol, colon2, item->port_min); else { uint16_t port_max = item->port_min + item->nr_ports - 1; fprintf(f, "%s%s%s%s%" PRIu16 "-%" PRIu16, family, colon1, protocol, colon2, item->port_min, port_max); } } void cgroup_context_dump_socket_bind_items(const CGroupSocketBindItem *items, FILE *f) { bool first = true; LIST_FOREACH(socket_bind_items, bi, items) { if (first) first = false; else fputc(' ', f); cgroup_context_dump_socket_bind_item(bi, f); } } int cgroup_context_add_device_allow(CGroupContext *c, const char *dev, CGroupDevicePermissions p) { _cleanup_free_ CGroupDeviceAllow *a = NULL; _cleanup_free_ char *d = NULL; assert(c); assert(dev); assert(p >= 0 && p < _CGROUP_DEVICE_PERMISSIONS_MAX); if (p == 0) p = _CGROUP_DEVICE_PERMISSIONS_ALL; a = new(CGroupDeviceAllow, 1); if (!a) return -ENOMEM; d = strdup(dev); if (!d) return -ENOMEM; *a = (CGroupDeviceAllow) { .path = TAKE_PTR(d), .permissions = p, }; LIST_PREPEND(device_allow, c->device_allow, a); TAKE_PTR(a); return 0; } int cgroup_context_add_or_update_device_allow(CGroupContext *c, const char *dev, CGroupDevicePermissions p) { assert(c); assert(dev); assert(p >= 0 && p < _CGROUP_DEVICE_PERMISSIONS_MAX); if (p == 0) p = _CGROUP_DEVICE_PERMISSIONS_ALL; LIST_FOREACH(device_allow, b, c->device_allow) if (path_equal(b->path, dev)) { b->permissions = p; return 0; } return cgroup_context_add_device_allow(c, dev, p); } int cgroup_context_add_bpf_foreign_program(CGroupContext *c, uint32_t attach_type, const char *bpffs_path) { CGroupBPFForeignProgram *p; _cleanup_free_ char *d = NULL; assert(c); assert(bpffs_path); if (!path_is_normalized(bpffs_path) || !path_is_absolute(bpffs_path)) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Path is not normalized."); d = strdup(bpffs_path); if (!d) return log_oom(); p = new(CGroupBPFForeignProgram, 1); if (!p) return log_oom(); *p = (CGroupBPFForeignProgram) { .attach_type = attach_type, .bpffs_path = TAKE_PTR(d), }; LIST_PREPEND(programs, c->bpf_foreign_programs, TAKE_PTR(p)); return 0; } #define UNIT_DEFINE_ANCESTOR_MEMORY_LOOKUP(entry) \ uint64_t unit_get_ancestor_##entry(Unit *u) { \ CGroupContext *c; \ \ /* 1. Is entry set in this unit? If so, use that. \ * 2. Is the default for this entry set in any \ * ancestor? If so, use that. \ * 3. Otherwise, return CGROUP_LIMIT_MIN. */ \ \ assert(u); \ \ c = unit_get_cgroup_context(u); \ if (c && c->entry##_set) \ return c->entry; \ \ while ((u = UNIT_GET_SLICE(u))) { \ c = unit_get_cgroup_context(u); \ if (c && c->default_##entry##_set) \ return c->default_##entry; \ } \ \ /* We've reached the root, but nobody had default for \ * this entry set, so set it to the kernel default. */ \ return CGROUP_LIMIT_MIN; \ } UNIT_DEFINE_ANCESTOR_MEMORY_LOOKUP(memory_low); UNIT_DEFINE_ANCESTOR_MEMORY_LOOKUP(startup_memory_low); UNIT_DEFINE_ANCESTOR_MEMORY_LOOKUP(memory_min); static void unit_set_xattr_graceful(Unit *u, const char *name, const void *data, size_t size) { int r; assert(u); assert(name); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; r = cg_set_xattr(crt->cgroup_path, name, data, size, 0); if (r < 0) log_unit_debug_errno(u, r, "Failed to set '%s' xattr on control group %s, ignoring: %m", name, empty_to_root(crt->cgroup_path)); } static void unit_remove_xattr_graceful(Unit *u, const char *name) { int r; assert(u); assert(name); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; r = cg_remove_xattr(crt->cgroup_path, name); if (r < 0 && !ERRNO_IS_XATTR_ABSENT(r)) log_unit_debug_errno(u, r, "Failed to remove '%s' xattr flag on control group %s, ignoring: %m", name, empty_to_root(crt->cgroup_path)); } static void cgroup_oomd_xattr_apply(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return; if (c->moom_preference == MANAGED_OOM_PREFERENCE_OMIT) unit_set_xattr_graceful(u, "user.oomd_omit", "1", 1); if (c->moom_preference == MANAGED_OOM_PREFERENCE_AVOID) unit_set_xattr_graceful(u, "user.oomd_avoid", "1", 1); if (c->moom_preference != MANAGED_OOM_PREFERENCE_AVOID) unit_remove_xattr_graceful(u, "user.oomd_avoid"); if (c->moom_preference != MANAGED_OOM_PREFERENCE_OMIT) unit_remove_xattr_graceful(u, "user.oomd_omit"); } static int cgroup_log_xattr_apply(Unit *u) { ExecContext *c; size_t len, allowed_patterns_len, denied_patterns_len; _cleanup_free_ char *patterns = NULL, *allowed_patterns = NULL, *denied_patterns = NULL; char *last; int r; assert(u); c = unit_get_exec_context(u); if (!c) /* Some unit types have a cgroup context but no exec context, so we do not log * any error here to avoid confusion. */ return 0; if (set_isempty(c->log_filter_allowed_patterns) && set_isempty(c->log_filter_denied_patterns)) { unit_remove_xattr_graceful(u, "user.journald_log_filter_patterns"); return 0; } r = set_make_nulstr(c->log_filter_allowed_patterns, &allowed_patterns, &allowed_patterns_len); if (r < 0) return log_debug_errno(r, "Failed to make nulstr from set: %m"); r = set_make_nulstr(c->log_filter_denied_patterns, &denied_patterns, &denied_patterns_len); if (r < 0) return log_debug_errno(r, "Failed to make nulstr from set: %m"); /* Use nul character separated strings without trailing nul */ allowed_patterns_len = LESS_BY(allowed_patterns_len, 1u); denied_patterns_len = LESS_BY(denied_patterns_len, 1u); len = allowed_patterns_len + 1 + denied_patterns_len; patterns = new(char, len); if (!patterns) return log_oom_debug(); last = mempcpy_safe(patterns, allowed_patterns, allowed_patterns_len); *(last++) = '\xff'; memcpy_safe(last, denied_patterns, denied_patterns_len); unit_set_xattr_graceful(u, "user.journald_log_filter_patterns", patterns, len); return 0; } static void cgroup_invocation_id_xattr_apply(Unit *u) { bool b; assert(u); b = !sd_id128_is_null(u->invocation_id); FOREACH_STRING(xn, "trusted.invocation_id", "user.invocation_id") { if (b) unit_set_xattr_graceful(u, xn, SD_ID128_TO_STRING(u->invocation_id), 32); else unit_remove_xattr_graceful(u, xn); } } static void cgroup_coredump_xattr_apply(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return; if (unit_cgroup_delegate(u) && c->coredump_receive) unit_set_xattr_graceful(u, "user.coredump_receive", "1", 1); else unit_remove_xattr_graceful(u, "user.coredump_receive"); } static void cgroup_delegate_xattr_apply(Unit *u) { bool b; assert(u); /* Indicate on the cgroup whether delegation is on, via an xattr. This is best-effort, as old kernels * didn't support xattrs on cgroups at all. Later they got support for setting 'trusted.*' xattrs, * and even later 'user.*' xattrs. We started setting this field when 'trusted.*' was added, and * given this is now pretty much API, let's continue to support that. But also set 'user.*' as well, * since it is readable by any user, not just CAP_SYS_ADMIN. This hence comes with slightly weaker * security (as users who got delegated cgroups could turn it off if they like), but this shouldn't * be a big problem given this communicates delegation state to clients, but the manager never reads * it. */ b = unit_cgroup_delegate(u); FOREACH_STRING(xn, "trusted.delegate", "user.delegate") { if (b) unit_set_xattr_graceful(u, xn, "1", 1); else unit_remove_xattr_graceful(u, xn); } } static void cgroup_survive_xattr_apply(Unit *u) { int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return; if (u->survive_final_kill_signal) { r = cg_set_xattr( crt->cgroup_path, "user.survive_final_kill_signal", "1", 1, /* flags= */ 0); /* user xattr support was added in kernel v5.7 */ if (ERRNO_IS_NEG_NOT_SUPPORTED(r)) r = cg_set_xattr( crt->cgroup_path, "trusted.survive_final_kill_signal", "1", 1, /* flags= */ 0); if (r < 0) log_unit_debug_errno(u, r, "Failed to set 'survive_final_kill_signal' xattr on control " "group %s, ignoring: %m", empty_to_root(crt->cgroup_path)); } else { unit_remove_xattr_graceful(u, "user.survive_final_kill_signal"); unit_remove_xattr_graceful(u, "trusted.survive_final_kill_signal"); } } static void cgroup_xattr_apply(Unit *u) { assert(u); /* The 'user.*' xattrs can be set from a user manager. */ cgroup_oomd_xattr_apply(u); cgroup_log_xattr_apply(u); cgroup_coredump_xattr_apply(u); if (!MANAGER_IS_SYSTEM(u->manager)) return; cgroup_invocation_id_xattr_apply(u); cgroup_delegate_xattr_apply(u); cgroup_survive_xattr_apply(u); } static int lookup_block_device(const char *p, dev_t *ret) { dev_t rdev, dev = 0; mode_t mode; int r; assert(p); assert(ret); r = device_path_parse_major_minor(p, &mode, &rdev); if (r == -ENODEV) { /* not a parsable device node, need to go to disk */ struct stat st; if (stat(p, &st) < 0) return log_warning_errno(errno, "Couldn't stat device '%s': %m", p); mode = st.st_mode; rdev = st.st_rdev; dev = st.st_dev; } else if (r < 0) return log_warning_errno(r, "Failed to parse major/minor from path '%s': %m", p); if (S_ISCHR(mode)) return log_warning_errno(SYNTHETIC_ERRNO(ENOTBLK), "Device node '%s' is a character device, but block device needed.", p); if (S_ISBLK(mode)) *ret = rdev; else if (major(dev) != 0) *ret = dev; /* If this is not a device node then use the block device this file is stored on */ else { /* If this is btrfs, getting the backing block device is a bit harder */ r = btrfs_get_block_device(p, ret); if (r == -ENOTTY) return log_warning_errno(SYNTHETIC_ERRNO(ENODEV), "'%s' is not a block device node, and file system block device cannot be determined or is not local.", p); if (r < 0) return log_warning_errno(r, "Failed to determine block device backing btrfs file system '%s': %m", p); } /* If this is a LUKS/DM device, recursively try to get the originating block device */ while (block_get_originating(*ret, ret) > 0); /* If this is a partition, try to get the originating block device */ (void) block_get_whole_disk(*ret, ret); return 0; } static bool cgroup_context_has_cpu_weight(CGroupContext *c) { return c->cpu_weight != CGROUP_WEIGHT_INVALID || c->startup_cpu_weight != CGROUP_WEIGHT_INVALID; } static bool cgroup_context_has_cpu_shares(CGroupContext *c) { return c->cpu_shares != CGROUP_CPU_SHARES_INVALID || c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID; } static bool cgroup_context_has_allowed_cpus(CGroupContext *c) { return c->cpuset_cpus.set || c->startup_cpuset_cpus.set; } static bool cgroup_context_has_allowed_mems(CGroupContext *c) { return c->cpuset_mems.set || c->startup_cpuset_mems.set; } uint64_t cgroup_context_cpu_weight(CGroupContext *c, ManagerState state) { assert(c); if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_cpu_weight != CGROUP_WEIGHT_INVALID) return c->startup_cpu_weight; else if (c->cpu_weight != CGROUP_WEIGHT_INVALID) return c->cpu_weight; else return CGROUP_WEIGHT_DEFAULT; } static uint64_t cgroup_context_cpu_shares(CGroupContext *c, ManagerState state) { if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_cpu_shares != CGROUP_CPU_SHARES_INVALID) return c->startup_cpu_shares; else if (c->cpu_shares != CGROUP_CPU_SHARES_INVALID) return c->cpu_shares; else return CGROUP_CPU_SHARES_DEFAULT; } static CPUSet *cgroup_context_allowed_cpus(CGroupContext *c, ManagerState state) { if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_cpuset_cpus.set) return &c->startup_cpuset_cpus; else return &c->cpuset_cpus; } static CPUSet *cgroup_context_allowed_mems(CGroupContext *c, ManagerState state) { if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_cpuset_mems.set) return &c->startup_cpuset_mems; else return &c->cpuset_mems; } usec_t cgroup_cpu_adjust_period(usec_t period, usec_t quota, usec_t resolution, usec_t max_period) { /* kernel uses a minimum resolution of 1ms, so both period and (quota * period) * need to be higher than that boundary. quota is specified in USecPerSec. * Additionally, period must be at most max_period. */ assert(quota > 0); return MIN(MAX3(period, resolution, resolution * USEC_PER_SEC / quota), max_period); } static usec_t cgroup_cpu_adjust_period_and_log(Unit *u, usec_t period, usec_t quota) { usec_t new_period; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return USEC_INFINITY; if (quota == USEC_INFINITY) /* Always use default period for infinity quota. */ return CGROUP_CPU_QUOTA_DEFAULT_PERIOD_USEC; if (period == USEC_INFINITY) /* Default period was requested. */ period = CGROUP_CPU_QUOTA_DEFAULT_PERIOD_USEC; /* Clamp to interval [1ms, 1s] */ new_period = cgroup_cpu_adjust_period(period, quota, USEC_PER_MSEC, USEC_PER_SEC); if (new_period != period) { log_unit_full(u, crt->warned_clamping_cpu_quota_period ? LOG_DEBUG : LOG_WARNING, "Clamping CPU interval for cpu.max: period is now %s", FORMAT_TIMESPAN(new_period, 1)); crt->warned_clamping_cpu_quota_period = true; } return new_period; } static void cgroup_apply_unified_cpu_weight(Unit *u, uint64_t weight) { char buf[DECIMAL_STR_MAX(uint64_t) + 2]; if (weight == CGROUP_WEIGHT_IDLE) return; xsprintf(buf, "%" PRIu64 "\n", weight); (void) set_attribute_and_warn(u, "cpu", "cpu.weight", buf); } static void cgroup_apply_unified_cpu_idle(Unit *u, uint64_t weight) { int r; bool is_idle; const char *idle_val; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; is_idle = weight == CGROUP_WEIGHT_IDLE; idle_val = one_zero(is_idle); r = cg_set_attribute("cpu", crt->cgroup_path, "cpu.idle", idle_val); if (r < 0 && (r != -ENOENT || is_idle)) log_unit_full_errno(u, LOG_LEVEL_CGROUP_WRITE(r), r, "Failed to set '%s' attribute on '%s' to '%s': %m", "cpu.idle", empty_to_root(crt->cgroup_path), idle_val); } static void cgroup_apply_unified_cpu_quota(Unit *u, usec_t quota, usec_t period) { char buf[(DECIMAL_STR_MAX(usec_t) + 1) * 2 + 1]; assert(u); period = cgroup_cpu_adjust_period_and_log(u, period, quota); if (quota != USEC_INFINITY) xsprintf(buf, USEC_FMT " " USEC_FMT "\n", MAX(quota * period / USEC_PER_SEC, USEC_PER_MSEC), period); else xsprintf(buf, "max " USEC_FMT "\n", period); (void) set_attribute_and_warn(u, "cpu", "cpu.max", buf); } static void cgroup_apply_legacy_cpu_shares(Unit *u, uint64_t shares) { char buf[DECIMAL_STR_MAX(uint64_t) + 2]; xsprintf(buf, "%" PRIu64 "\n", shares); (void) set_attribute_and_warn(u, "cpu", "cpu.shares", buf); } static void cgroup_apply_legacy_cpu_quota(Unit *u, usec_t quota, usec_t period) { char buf[DECIMAL_STR_MAX(usec_t) + 2]; period = cgroup_cpu_adjust_period_and_log(u, period, quota); xsprintf(buf, USEC_FMT "\n", period); (void) set_attribute_and_warn(u, "cpu", "cpu.cfs_period_us", buf); if (quota != USEC_INFINITY) { xsprintf(buf, USEC_FMT "\n", MAX(quota * period / USEC_PER_SEC, USEC_PER_MSEC)); (void) set_attribute_and_warn(u, "cpu", "cpu.cfs_quota_us", buf); } else (void) set_attribute_and_warn(u, "cpu", "cpu.cfs_quota_us", "-1\n"); } static uint64_t cgroup_cpu_shares_to_weight(uint64_t shares) { return CLAMP(shares * CGROUP_WEIGHT_DEFAULT / CGROUP_CPU_SHARES_DEFAULT, CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX); } static uint64_t cgroup_cpu_weight_to_shares(uint64_t weight) { /* we don't support idle in cgroupv1 */ if (weight == CGROUP_WEIGHT_IDLE) return CGROUP_CPU_SHARES_MIN; return CLAMP(weight * CGROUP_CPU_SHARES_DEFAULT / CGROUP_WEIGHT_DEFAULT, CGROUP_CPU_SHARES_MIN, CGROUP_CPU_SHARES_MAX); } static void cgroup_apply_unified_cpuset(Unit *u, const CPUSet *cpus, const char *name) { _cleanup_free_ char *buf = NULL; buf = cpu_set_to_range_string(cpus); if (!buf) { log_oom(); return; } (void) set_attribute_and_warn(u, "cpuset", name, buf); } static bool cgroup_context_has_io_config(CGroupContext *c) { return c->io_accounting || c->io_weight != CGROUP_WEIGHT_INVALID || c->startup_io_weight != CGROUP_WEIGHT_INVALID || c->io_device_weights || c->io_device_latencies || c->io_device_limits; } static bool cgroup_context_has_blockio_config(CGroupContext *c) { return c->blockio_accounting || c->blockio_weight != CGROUP_BLKIO_WEIGHT_INVALID || c->startup_blockio_weight != CGROUP_BLKIO_WEIGHT_INVALID || c->blockio_device_weights || c->blockio_device_bandwidths; } static uint64_t cgroup_context_io_weight(CGroupContext *c, ManagerState state) { if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_io_weight != CGROUP_WEIGHT_INVALID) return c->startup_io_weight; if (c->io_weight != CGROUP_WEIGHT_INVALID) return c->io_weight; return CGROUP_WEIGHT_DEFAULT; } static uint64_t cgroup_context_blkio_weight(CGroupContext *c, ManagerState state) { if (IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING) && c->startup_blockio_weight != CGROUP_BLKIO_WEIGHT_INVALID) return c->startup_blockio_weight; if (c->blockio_weight != CGROUP_BLKIO_WEIGHT_INVALID) return c->blockio_weight; return CGROUP_BLKIO_WEIGHT_DEFAULT; } static uint64_t cgroup_weight_blkio_to_io(uint64_t blkio_weight) { return CLAMP(blkio_weight * CGROUP_WEIGHT_DEFAULT / CGROUP_BLKIO_WEIGHT_DEFAULT, CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX); } static uint64_t cgroup_weight_io_to_blkio(uint64_t io_weight) { return CLAMP(io_weight * CGROUP_BLKIO_WEIGHT_DEFAULT / CGROUP_WEIGHT_DEFAULT, CGROUP_BLKIO_WEIGHT_MIN, CGROUP_BLKIO_WEIGHT_MAX); } static int set_bfq_weight(Unit *u, const char *controller, dev_t dev, uint64_t io_weight) { static const char * const prop_names[] = { "IOWeight", "BlockIOWeight", "IODeviceWeight", "BlockIODeviceWeight", }; static bool warned = false; char buf[DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+STRLEN("\n")]; const char *p; uint64_t bfq_weight; int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; /* FIXME: drop this function when distro kernels properly support BFQ through "io.weight" * See also: https://github.com/systemd/systemd/pull/13335 and * https://github.com/torvalds/linux/commit/65752aef0a407e1ef17ec78a7fc31ba4e0b360f9. */ p = strjoina(controller, ".bfq.weight"); /* Adjust to kernel range is 1..1000, the default is 100. */ bfq_weight = BFQ_WEIGHT(io_weight); if (major(dev) > 0) xsprintf(buf, DEVNUM_FORMAT_STR " %" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), bfq_weight); else xsprintf(buf, "%" PRIu64 "\n", bfq_weight); r = cg_set_attribute(controller, crt->cgroup_path, p, buf); /* FIXME: drop this when kernels prior * 795fe54c2a82 ("bfq: Add per-device weight") v5.4 * are not interesting anymore. Old kernels will fail with EINVAL, while new kernels won't return * EINVAL on properly formatted input by us. Treat EINVAL accordingly. */ if (r == -EINVAL && major(dev) > 0) { if (!warned) { log_unit_warning(u, "Kernel version does not accept per-device setting in %s.", p); warned = true; } r = -EOPNOTSUPP; /* mask as unconfigured device */ } else if (r >= 0 && io_weight != bfq_weight) log_unit_debug(u, "%s=%" PRIu64 " scaled to %s=%" PRIu64, prop_names[2*(major(dev) > 0) + streq(controller, "blkio")], io_weight, p, bfq_weight); return r; } static void cgroup_apply_io_device_weight(Unit *u, const char *dev_path, uint64_t io_weight) { char buf[DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+1]; dev_t dev; int r, r1, r2; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; if (lookup_block_device(dev_path, &dev) < 0) return; r1 = set_bfq_weight(u, "io", dev, io_weight); xsprintf(buf, DEVNUM_FORMAT_STR " %" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), io_weight); r2 = cg_set_attribute("io", crt->cgroup_path, "io.weight", buf); /* Look at the configured device, when both fail, prefer io.weight errno. */ r = r2 == -EOPNOTSUPP ? r1 : r2; if (r < 0) log_unit_full_errno(u, LOG_LEVEL_CGROUP_WRITE(r), r, "Failed to set 'io[.bfq].weight' attribute on '%s' to '%.*s': %m", empty_to_root(crt->cgroup_path), (int) strcspn(buf, NEWLINE), buf); } static void cgroup_apply_blkio_device_weight(Unit *u, const char *dev_path, uint64_t blkio_weight) { char buf[DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+1]; dev_t dev; int r; r = lookup_block_device(dev_path, &dev); if (r < 0) return; xsprintf(buf, DEVNUM_FORMAT_STR " %" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), blkio_weight); (void) set_attribute_and_warn(u, "blkio", "blkio.weight_device", buf); } static void cgroup_apply_io_device_latency(Unit *u, const char *dev_path, usec_t target) { char buf[DECIMAL_STR_MAX(dev_t)*2+2+7+DECIMAL_STR_MAX(uint64_t)+1]; dev_t dev; int r; r = lookup_block_device(dev_path, &dev); if (r < 0) return; if (target != USEC_INFINITY) xsprintf(buf, DEVNUM_FORMAT_STR " target=%" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), target); else xsprintf(buf, DEVNUM_FORMAT_STR " target=max\n", DEVNUM_FORMAT_VAL(dev)); (void) set_attribute_and_warn(u, "io", "io.latency", buf); } static void cgroup_apply_io_device_limit(Unit *u, const char *dev_path, uint64_t *limits) { char limit_bufs[_CGROUP_IO_LIMIT_TYPE_MAX][DECIMAL_STR_MAX(uint64_t)], buf[DECIMAL_STR_MAX(dev_t)*2+2+(6+DECIMAL_STR_MAX(uint64_t)+1)*4]; dev_t dev; if (lookup_block_device(dev_path, &dev) < 0) return; for (CGroupIOLimitType type = 0; type < _CGROUP_IO_LIMIT_TYPE_MAX; type++) if (limits[type] != cgroup_io_limit_defaults[type]) xsprintf(limit_bufs[type], "%" PRIu64, limits[type]); else xsprintf(limit_bufs[type], "%s", limits[type] == CGROUP_LIMIT_MAX ? "max" : "0"); xsprintf(buf, DEVNUM_FORMAT_STR " rbps=%s wbps=%s riops=%s wiops=%s\n", DEVNUM_FORMAT_VAL(dev), limit_bufs[CGROUP_IO_RBPS_MAX], limit_bufs[CGROUP_IO_WBPS_MAX], limit_bufs[CGROUP_IO_RIOPS_MAX], limit_bufs[CGROUP_IO_WIOPS_MAX]); (void) set_attribute_and_warn(u, "io", "io.max", buf); } static void cgroup_apply_blkio_device_limit(Unit *u, const char *dev_path, uint64_t rbps, uint64_t wbps) { char buf[DECIMAL_STR_MAX(dev_t)*2+2+DECIMAL_STR_MAX(uint64_t)+1]; dev_t dev; if (lookup_block_device(dev_path, &dev) < 0) return; sprintf(buf, DEVNUM_FORMAT_STR " %" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), rbps); (void) set_attribute_and_warn(u, "blkio", "blkio.throttle.read_bps_device", buf); sprintf(buf, DEVNUM_FORMAT_STR " %" PRIu64 "\n", DEVNUM_FORMAT_VAL(dev), wbps); (void) set_attribute_and_warn(u, "blkio", "blkio.throttle.write_bps_device", buf); } static bool unit_has_unified_memory_config(Unit *u) { CGroupContext *c; assert(u); assert_se(c = unit_get_cgroup_context(u)); return unit_get_ancestor_memory_min(u) > 0 || unit_get_ancestor_memory_low(u) > 0 || unit_get_ancestor_startup_memory_low(u) > 0 || c->memory_high != CGROUP_LIMIT_MAX || c->startup_memory_high_set || c->memory_max != CGROUP_LIMIT_MAX || c->startup_memory_max_set || c->memory_swap_max != CGROUP_LIMIT_MAX || c->startup_memory_swap_max_set || c->memory_zswap_max != CGROUP_LIMIT_MAX || c->startup_memory_zswap_max_set; } static void cgroup_apply_unified_memory_limit(Unit *u, const char *file, uint64_t v) { char buf[DECIMAL_STR_MAX(uint64_t) + 1] = "max\n"; if (v != CGROUP_LIMIT_MAX) xsprintf(buf, "%" PRIu64 "\n", v); (void) set_attribute_and_warn(u, "memory", file, buf); } static void cgroup_apply_firewall(Unit *u) { assert(u); /* Best-effort: let's apply IP firewalling and/or accounting if that's enabled */ if (bpf_firewall_compile(u) < 0) return; (void) bpf_firewall_load_custom(u); (void) bpf_firewall_install(u); } void unit_modify_nft_set(Unit *u, bool add) { int r; assert(u); if (!MANAGER_IS_SYSTEM(u->manager)) return; if (!UNIT_HAS_CGROUP_CONTEXT(u)) return; if (cg_all_unified() <= 0) return; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || crt->cgroup_id == 0) return; if (!u->manager->fw_ctx) { r = fw_ctx_new_full(&u->manager->fw_ctx, /* init_tables= */ false); if (r < 0) return; assert(u->manager->fw_ctx); } CGroupContext *c = ASSERT_PTR(unit_get_cgroup_context(u)); FOREACH_ARRAY(nft_set, c->nft_set_context.sets, c->nft_set_context.n_sets) { if (nft_set->source != NFT_SET_SOURCE_CGROUP) continue; uint64_t element = crt->cgroup_id; r = nft_set_element_modify_any(u->manager->fw_ctx, add, nft_set->nfproto, nft_set->table, nft_set->set, &element, sizeof(element)); if (r < 0) log_warning_errno(r, "Failed to %s NFT set: family %s, table %s, set %s, cgroup %" PRIu64 ", ignoring: %m", add? "add" : "delete", nfproto_to_string(nft_set->nfproto), nft_set->table, nft_set->set, crt->cgroup_id); else log_debug("%s NFT set: family %s, table %s, set %s, cgroup %" PRIu64, add? "Added" : "Deleted", nfproto_to_string(nft_set->nfproto), nft_set->table, nft_set->set, crt->cgroup_id); } } static void cgroup_apply_socket_bind(Unit *u) { assert(u); (void) bpf_socket_bind_install(u); } static void cgroup_apply_restrict_network_interfaces(Unit *u) { assert(u); (void) bpf_restrict_ifaces_install(u); } static int cgroup_apply_devices(Unit *u) { _cleanup_(bpf_program_freep) BPFProgram *prog = NULL; CGroupContext *c; CGroupDevicePolicy policy; int r; assert_se(c = unit_get_cgroup_context(u)); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; policy = c->device_policy; if (cg_all_unified() > 0) { r = bpf_devices_cgroup_init(&prog, policy, c->device_allow); if (r < 0) return log_unit_warning_errno(u, r, "Failed to initialize device control bpf program: %m"); } else { /* Changing the devices list of a populated cgroup might result in EINVAL, hence ignore * EINVAL here. */ if (c->device_allow || policy != CGROUP_DEVICE_POLICY_AUTO) r = cg_set_attribute("devices", crt->cgroup_path, "devices.deny", "a"); else r = cg_set_attribute("devices", crt->cgroup_path, "devices.allow", "a"); if (r < 0) log_unit_full_errno(u, IN_SET(r, -ENOENT, -EROFS, -EINVAL, -EACCES, -EPERM) ? LOG_DEBUG : LOG_WARNING, r, "Failed to reset devices.allow/devices.deny: %m"); } bool allow_list_static = policy == CGROUP_DEVICE_POLICY_CLOSED || (policy == CGROUP_DEVICE_POLICY_AUTO && c->device_allow); bool any = false; if (allow_list_static) { r = bpf_devices_allow_list_static(prog, crt->cgroup_path); if (r > 0) any = true; } LIST_FOREACH(device_allow, a, c->device_allow) { const char *val; if (a->permissions == 0) continue; if (path_startswith(a->path, "/dev/")) r = bpf_devices_allow_list_device(prog, crt->cgroup_path, a->path, a->permissions); else if ((val = startswith(a->path, "block-"))) r = bpf_devices_allow_list_major(prog, crt->cgroup_path, val, 'b', a->permissions); else if ((val = startswith(a->path, "char-"))) r = bpf_devices_allow_list_major(prog, crt->cgroup_path, val, 'c', a->permissions); else { log_unit_debug(u, "Ignoring device '%s' while writing cgroup attribute.", a->path); continue; } if (r > 0) any = true; } if (prog && !any) { log_unit_warning(u, "No devices matched by device filter."); /* The kernel verifier would reject a program we would build with the normal intro and outro but no allow-listing rules (outro would contain an unreachable instruction for successful return). */ policy = CGROUP_DEVICE_POLICY_STRICT; } r = bpf_devices_apply_policy(&prog, policy, any, crt->cgroup_path, &crt->bpf_device_control_installed); if (r < 0) { static bool warned = false; log_full_errno(warned ? LOG_DEBUG : LOG_WARNING, r, "Unit %s configures device ACL, but the local system doesn't seem to support the BPF-based device controller.\n" "Proceeding WITHOUT applying ACL (all devices will be accessible)!\n" "(This warning is only shown for the first loaded unit using device ACL.)", u->id); warned = true; } return r; } static void set_io_weight(Unit *u, uint64_t weight) { char buf[STRLEN("default \n")+DECIMAL_STR_MAX(uint64_t)]; assert(u); (void) set_bfq_weight(u, "io", makedev(0, 0), weight); xsprintf(buf, "default %" PRIu64 "\n", weight); (void) set_attribute_and_warn(u, "io", "io.weight", buf); } static void set_blkio_weight(Unit *u, uint64_t weight) { char buf[STRLEN("\n")+DECIMAL_STR_MAX(uint64_t)]; assert(u); (void) set_bfq_weight(u, "blkio", makedev(0, 0), weight); xsprintf(buf, "%" PRIu64 "\n", weight); (void) set_attribute_and_warn(u, "blkio", "blkio.weight", buf); } static void cgroup_apply_bpf_foreign_program(Unit *u) { assert(u); (void) bpf_foreign_install(u); } static void cgroup_context_apply( Unit *u, CGroupMask apply_mask, ManagerState state) { bool is_host_root, is_local_root; const char *path; CGroupContext *c; int r; assert(u); /* Nothing to do? Exit early! */ if (apply_mask == 0) return; /* Some cgroup attributes are not supported on the host root cgroup, hence silently ignore them here. And other * attributes should only be managed for cgroups further down the tree. */ is_local_root = unit_has_name(u, SPECIAL_ROOT_SLICE); is_host_root = unit_has_host_root_cgroup(u); assert_se(c = unit_get_cgroup_context(u)); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; path = crt->cgroup_path; if (is_local_root) /* Make sure we don't try to display messages with an empty path. */ path = "/"; /* We generally ignore errors caused by read-only mounted cgroup trees (assuming we are running in a container * then), and missing cgroups, i.e. EROFS and ENOENT. */ /* In fully unified mode these attributes don't exist on the host cgroup root. On legacy the weights exist, but * setting the weight makes very little sense on the host root cgroup, as there are no other cgroups at this * level. The quota exists there too, but any attempt to write to it is refused with EINVAL. Inside of * containers we want to leave control of these to the container manager (and if cgroup v2 delegation is used * we couldn't even write to them if we wanted to). */ if ((apply_mask & CGROUP_MASK_CPU) && !is_local_root) { if (cg_all_unified() > 0) { uint64_t weight; if (cgroup_context_has_cpu_weight(c)) weight = cgroup_context_cpu_weight(c, state); else if (cgroup_context_has_cpu_shares(c)) { uint64_t shares; shares = cgroup_context_cpu_shares(c, state); weight = cgroup_cpu_shares_to_weight(shares); log_cgroup_compat(u, "Applying [Startup]CPUShares=%" PRIu64 " as [Startup]CPUWeight=%" PRIu64 " on %s", shares, weight, path); } else weight = CGROUP_WEIGHT_DEFAULT; cgroup_apply_unified_cpu_idle(u, weight); cgroup_apply_unified_cpu_weight(u, weight); cgroup_apply_unified_cpu_quota(u, c->cpu_quota_per_sec_usec, c->cpu_quota_period_usec); } else { uint64_t shares; if (cgroup_context_has_cpu_weight(c)) { uint64_t weight; weight = cgroup_context_cpu_weight(c, state); shares = cgroup_cpu_weight_to_shares(weight); log_cgroup_compat(u, "Applying [Startup]CPUWeight=%" PRIu64 " as [Startup]CPUShares=%" PRIu64 " on %s", weight, shares, path); } else if (cgroup_context_has_cpu_shares(c)) shares = cgroup_context_cpu_shares(c, state); else shares = CGROUP_CPU_SHARES_DEFAULT; cgroup_apply_legacy_cpu_shares(u, shares); cgroup_apply_legacy_cpu_quota(u, c->cpu_quota_per_sec_usec, c->cpu_quota_period_usec); } } if ((apply_mask & CGROUP_MASK_CPUSET) && !is_local_root) { cgroup_apply_unified_cpuset(u, cgroup_context_allowed_cpus(c, state), "cpuset.cpus"); cgroup_apply_unified_cpuset(u, cgroup_context_allowed_mems(c, state), "cpuset.mems"); } /* The 'io' controller attributes are not exported on the host's root cgroup (being a pure cgroup v2 * controller), and in case of containers we want to leave control of these attributes to the container manager * (and we couldn't access that stuff anyway, even if we tried if proper delegation is used). */ if ((apply_mask & CGROUP_MASK_IO) && !is_local_root) { bool has_io, has_blockio; uint64_t weight; has_io = cgroup_context_has_io_config(c); has_blockio = cgroup_context_has_blockio_config(c); if (has_io) weight = cgroup_context_io_weight(c, state); else if (has_blockio) { uint64_t blkio_weight; blkio_weight = cgroup_context_blkio_weight(c, state); weight = cgroup_weight_blkio_to_io(blkio_weight); log_cgroup_compat(u, "Applying [Startup]BlockIOWeight=%" PRIu64 " as [Startup]IOWeight=%" PRIu64, blkio_weight, weight); } else weight = CGROUP_WEIGHT_DEFAULT; set_io_weight(u, weight); if (has_io) { LIST_FOREACH(device_weights, w, c->io_device_weights) cgroup_apply_io_device_weight(u, w->path, w->weight); LIST_FOREACH(device_limits, limit, c->io_device_limits) cgroup_apply_io_device_limit(u, limit->path, limit->limits); LIST_FOREACH(device_latencies, latency, c->io_device_latencies) cgroup_apply_io_device_latency(u, latency->path, latency->target_usec); } else if (has_blockio) { LIST_FOREACH(device_weights, w, c->blockio_device_weights) { weight = cgroup_weight_blkio_to_io(w->weight); log_cgroup_compat(u, "Applying BlockIODeviceWeight=%" PRIu64 " as IODeviceWeight=%" PRIu64 " for %s", w->weight, weight, w->path); cgroup_apply_io_device_weight(u, w->path, weight); } LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) { uint64_t limits[_CGROUP_IO_LIMIT_TYPE_MAX]; for (CGroupIOLimitType type = 0; type < _CGROUP_IO_LIMIT_TYPE_MAX; type++) limits[type] = cgroup_io_limit_defaults[type]; limits[CGROUP_IO_RBPS_MAX] = b->rbps; limits[CGROUP_IO_WBPS_MAX] = b->wbps; log_cgroup_compat(u, "Applying BlockIO{Read|Write}Bandwidth=%" PRIu64 " %" PRIu64 " as IO{Read|Write}BandwidthMax= for %s", b->rbps, b->wbps, b->path); cgroup_apply_io_device_limit(u, b->path, limits); } } } if (apply_mask & CGROUP_MASK_BLKIO) { bool has_io, has_blockio; has_io = cgroup_context_has_io_config(c); has_blockio = cgroup_context_has_blockio_config(c); /* Applying a 'weight' never makes sense for the host root cgroup, and for containers this should be * left to our container manager, too. */ if (!is_local_root) { uint64_t weight; if (has_io) { uint64_t io_weight; io_weight = cgroup_context_io_weight(c, state); weight = cgroup_weight_io_to_blkio(cgroup_context_io_weight(c, state)); log_cgroup_compat(u, "Applying [Startup]IOWeight=%" PRIu64 " as [Startup]BlockIOWeight=%" PRIu64, io_weight, weight); } else if (has_blockio) weight = cgroup_context_blkio_weight(c, state); else weight = CGROUP_BLKIO_WEIGHT_DEFAULT; set_blkio_weight(u, weight); if (has_io) LIST_FOREACH(device_weights, w, c->io_device_weights) { weight = cgroup_weight_io_to_blkio(w->weight); log_cgroup_compat(u, "Applying IODeviceWeight=%" PRIu64 " as BlockIODeviceWeight=%" PRIu64 " for %s", w->weight, weight, w->path); cgroup_apply_blkio_device_weight(u, w->path, weight); } else if (has_blockio) LIST_FOREACH(device_weights, w, c->blockio_device_weights) cgroup_apply_blkio_device_weight(u, w->path, w->weight); } /* The bandwidth limits are something that make sense to be applied to the host's root but not container * roots, as there we want the container manager to handle it */ if (is_host_root || !is_local_root) { if (has_io) LIST_FOREACH(device_limits, l, c->io_device_limits) { log_cgroup_compat(u, "Applying IO{Read|Write}Bandwidth=%" PRIu64 " %" PRIu64 " as BlockIO{Read|Write}BandwidthMax= for %s", l->limits[CGROUP_IO_RBPS_MAX], l->limits[CGROUP_IO_WBPS_MAX], l->path); cgroup_apply_blkio_device_limit(u, l->path, l->limits[CGROUP_IO_RBPS_MAX], l->limits[CGROUP_IO_WBPS_MAX]); } else if (has_blockio) LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) cgroup_apply_blkio_device_limit(u, b->path, b->rbps, b->wbps); } } /* In unified mode 'memory' attributes do not exist on the root cgroup. In legacy mode 'memory.limit_in_bytes' * exists on the root cgroup, but any writes to it are refused with EINVAL. And if we run in a container we * want to leave control to the container manager (and if proper cgroup v2 delegation is used we couldn't even * write to this if we wanted to.) */ if ((apply_mask & CGROUP_MASK_MEMORY) && !is_local_root) { if (cg_all_unified() > 0) { uint64_t max, swap_max = CGROUP_LIMIT_MAX, zswap_max = CGROUP_LIMIT_MAX, high = CGROUP_LIMIT_MAX; if (unit_has_unified_memory_config(u)) { bool startup = IN_SET(state, MANAGER_STARTING, MANAGER_INITIALIZING, MANAGER_STOPPING); high = startup && c->startup_memory_high_set ? c->startup_memory_high : c->memory_high; max = startup && c->startup_memory_max_set ? c->startup_memory_max : c->memory_max; swap_max = startup && c->startup_memory_swap_max_set ? c->startup_memory_swap_max : c->memory_swap_max; zswap_max = startup && c->startup_memory_zswap_max_set ? c->startup_memory_zswap_max : c->memory_zswap_max; } else { max = c->memory_limit; if (max != CGROUP_LIMIT_MAX) log_cgroup_compat(u, "Applying MemoryLimit=%" PRIu64 " as MemoryMax=", max); } cgroup_apply_unified_memory_limit(u, "memory.min", unit_get_ancestor_memory_min(u)); cgroup_apply_unified_memory_limit(u, "memory.low", unit_get_ancestor_memory_low(u)); cgroup_apply_unified_memory_limit(u, "memory.high", high); cgroup_apply_unified_memory_limit(u, "memory.max", max); cgroup_apply_unified_memory_limit(u, "memory.swap.max", swap_max); cgroup_apply_unified_memory_limit(u, "memory.zswap.max", zswap_max); (void) set_attribute_and_warn(u, "memory", "memory.oom.group", one_zero(c->memory_oom_group)); (void) set_attribute_and_warn(u, "memory", "memory.zswap.writeback", one_zero(c->memory_zswap_writeback)); } else { char buf[DECIMAL_STR_MAX(uint64_t) + 1]; uint64_t val; if (unit_has_unified_memory_config(u)) { val = c->memory_max; if (val != CGROUP_LIMIT_MAX) log_cgroup_compat(u, "Applying MemoryMax=%" PRIu64 " as MemoryLimit=", val); } else val = c->memory_limit; if (val == CGROUP_LIMIT_MAX) strncpy(buf, "-1\n", sizeof(buf)); else xsprintf(buf, "%" PRIu64 "\n", val); (void) set_attribute_and_warn(u, "memory", "memory.limit_in_bytes", buf); } } /* On cgroup v2 we can apply BPF everywhere. On cgroup v1 we apply it everywhere except for the root of * containers, where we leave this to the manager */ if ((apply_mask & (CGROUP_MASK_DEVICES | CGROUP_MASK_BPF_DEVICES)) && (is_host_root || cg_all_unified() > 0 || !is_local_root)) (void) cgroup_apply_devices(u); if (apply_mask & CGROUP_MASK_PIDS) { if (is_host_root) { /* So, the "pids" controller does not expose anything on the root cgroup, in order not to * replicate knobs exposed elsewhere needlessly. We abstract this away here however, and when * the knobs of the root cgroup are modified propagate this to the relevant sysctls. There's a * non-obvious asymmetry however: unlike the cgroup properties we don't really want to take * exclusive ownership of the sysctls, but we still want to honour things if the user sets * limits. Hence we employ sort of a one-way strategy: when the user sets a bounded limit * through us it counts. When the user afterwards unsets it again (i.e. sets it to unbounded) * it also counts. But if the user never set a limit through us (i.e. we are the default of * "unbounded") we leave things unmodified. For this we manage a global boolean that we turn on * the first time we set a limit. Note that this boolean is flushed out on manager reload, * which is desirable so that there's an official way to release control of the sysctl from * systemd: set the limit to unbounded and reload. */ if (cgroup_tasks_max_isset(&c->tasks_max)) { u->manager->sysctl_pid_max_changed = true; r = procfs_tasks_set_limit(cgroup_tasks_max_resolve(&c->tasks_max)); } else if (u->manager->sysctl_pid_max_changed) r = procfs_tasks_set_limit(TASKS_MAX); else r = 0; if (r < 0) log_unit_full_errno(u, LOG_LEVEL_CGROUP_WRITE(r), r, "Failed to write to tasks limit sysctls: %m"); } /* The attribute itself is not available on the host root cgroup, and in the container case we want to * leave it for the container manager. */ if (!is_local_root) { if (cgroup_tasks_max_isset(&c->tasks_max)) { char buf[DECIMAL_STR_MAX(uint64_t) + 1]; xsprintf(buf, "%" PRIu64 "\n", cgroup_tasks_max_resolve(&c->tasks_max)); (void) set_attribute_and_warn(u, "pids", "pids.max", buf); } else (void) set_attribute_and_warn(u, "pids", "pids.max", "max\n"); } } if (apply_mask & CGROUP_MASK_BPF_FIREWALL) cgroup_apply_firewall(u); if (apply_mask & CGROUP_MASK_BPF_FOREIGN) cgroup_apply_bpf_foreign_program(u); if (apply_mask & CGROUP_MASK_BPF_SOCKET_BIND) cgroup_apply_socket_bind(u); if (apply_mask & CGROUP_MASK_BPF_RESTRICT_NETWORK_INTERFACES) cgroup_apply_restrict_network_interfaces(u); unit_modify_nft_set(u, /* add = */ true); } static bool unit_get_needs_bpf_firewall(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return false; if (c->ip_accounting || !set_isempty(c->ip_address_allow) || !set_isempty(c->ip_address_deny) || c->ip_filters_ingress || c->ip_filters_egress) return true; /* If any parent slice has an IP access list defined, it applies too */ for (Unit *p = UNIT_GET_SLICE(u); p; p = UNIT_GET_SLICE(p)) { c = unit_get_cgroup_context(p); if (!c) return false; if (!set_isempty(c->ip_address_allow) || !set_isempty(c->ip_address_deny)) return true; } return false; } static bool unit_get_needs_bpf_foreign_program(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return false; return !!c->bpf_foreign_programs; } static bool unit_get_needs_socket_bind(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return false; return c->socket_bind_allow || c->socket_bind_deny; } static bool unit_get_needs_restrict_network_interfaces(Unit *u) { CGroupContext *c; assert(u); c = unit_get_cgroup_context(u); if (!c) return false; return !set_isempty(c->restrict_network_interfaces); } static CGroupMask unit_get_cgroup_mask(Unit *u) { CGroupMask mask = 0; CGroupContext *c; assert(u); assert_se(c = unit_get_cgroup_context(u)); /* Figure out which controllers we need, based on the cgroup context object */ if (c->cpu_accounting) mask |= get_cpu_accounting_mask(); if (cgroup_context_has_cpu_weight(c) || cgroup_context_has_cpu_shares(c) || c->cpu_quota_per_sec_usec != USEC_INFINITY) mask |= CGROUP_MASK_CPU; if (cgroup_context_has_allowed_cpus(c) || cgroup_context_has_allowed_mems(c)) mask |= CGROUP_MASK_CPUSET; if (cgroup_context_has_io_config(c) || cgroup_context_has_blockio_config(c)) mask |= CGROUP_MASK_IO | CGROUP_MASK_BLKIO; if (c->memory_accounting || c->memory_limit != CGROUP_LIMIT_MAX || unit_has_unified_memory_config(u)) mask |= CGROUP_MASK_MEMORY; if (c->device_allow || c->device_policy != CGROUP_DEVICE_POLICY_AUTO) mask |= CGROUP_MASK_DEVICES | CGROUP_MASK_BPF_DEVICES; if (c->tasks_accounting || cgroup_tasks_max_isset(&c->tasks_max)) mask |= CGROUP_MASK_PIDS; return CGROUP_MASK_EXTEND_JOINED(mask); } static CGroupMask unit_get_bpf_mask(Unit *u) { CGroupMask mask = 0; /* Figure out which controllers we need, based on the cgroup context, possibly taking into account children * too. */ if (unit_get_needs_bpf_firewall(u)) mask |= CGROUP_MASK_BPF_FIREWALL; if (unit_get_needs_bpf_foreign_program(u)) mask |= CGROUP_MASK_BPF_FOREIGN; if (unit_get_needs_socket_bind(u)) mask |= CGROUP_MASK_BPF_SOCKET_BIND; if (unit_get_needs_restrict_network_interfaces(u)) mask |= CGROUP_MASK_BPF_RESTRICT_NETWORK_INTERFACES; return mask; } CGroupMask unit_get_own_mask(Unit *u) { CGroupContext *c; /* Returns the mask of controllers the unit needs for itself. If a unit is not properly loaded, return an empty * mask, as we shouldn't reflect it in the cgroup hierarchy then. */ if (u->load_state != UNIT_LOADED) return 0; c = unit_get_cgroup_context(u); if (!c) return 0; return unit_get_cgroup_mask(u) | unit_get_bpf_mask(u) | unit_get_delegate_mask(u); } CGroupMask unit_get_delegate_mask(Unit *u) { CGroupContext *c; /* If delegation is turned on, then turn on selected controllers, unless we are on the legacy hierarchy and the * process we fork into is known to drop privileges, and hence shouldn't get access to the controllers. * * Note that on the unified hierarchy it is safe to delegate controllers to unprivileged services. */ if (!unit_cgroup_delegate(u)) return 0; if (cg_all_unified() <= 0) { ExecContext *e; e = unit_get_exec_context(u); if (e && !exec_context_maintains_privileges(e)) return 0; } assert_se(c = unit_get_cgroup_context(u)); return CGROUP_MASK_EXTEND_JOINED(c->delegate_controllers); } static CGroupMask unit_get_subtree_mask(Unit *u) { /* Returns the mask of this subtree, meaning of the group * itself and its children. */ return unit_get_own_mask(u) | unit_get_members_mask(u); } CGroupMask unit_get_members_mask(Unit *u) { assert(u); /* Returns the mask of controllers all of the unit's children require, merged */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (crt && crt->cgroup_members_mask_valid) return crt->cgroup_members_mask; /* Use cached value if possible */ CGroupMask m = 0; if (u->type == UNIT_SLICE) { Unit *member; UNIT_FOREACH_DEPENDENCY(member, u, UNIT_ATOM_SLICE_OF) m |= unit_get_subtree_mask(member); /* note that this calls ourselves again, for the children */ } if (crt) { crt->cgroup_members_mask = m; crt->cgroup_members_mask_valid = true; } return m; } CGroupMask unit_get_siblings_mask(Unit *u) { Unit *slice; assert(u); /* Returns the mask of controllers all of the unit's siblings * require, i.e. the members mask of the unit's parent slice * if there is one. */ slice = UNIT_GET_SLICE(u); if (slice) return unit_get_members_mask(slice); return unit_get_subtree_mask(u); /* we are the top-level slice */ } static CGroupMask unit_get_disable_mask(Unit *u) { CGroupContext *c; c = unit_get_cgroup_context(u); if (!c) return 0; return c->disable_controllers; } CGroupMask unit_get_ancestor_disable_mask(Unit *u) { CGroupMask mask; Unit *slice; assert(u); mask = unit_get_disable_mask(u); /* Returns the mask of controllers which are marked as forcibly * disabled in any ancestor unit or the unit in question. */ slice = UNIT_GET_SLICE(u); if (slice) mask |= unit_get_ancestor_disable_mask(slice); return mask; } CGroupMask unit_get_target_mask(Unit *u) { CGroupMask own_mask, mask; /* This returns the cgroup mask of all controllers to enable for a specific cgroup, i.e. everything * it needs itself, plus all that its children need, plus all that its siblings need. This is * primarily useful on the legacy cgroup hierarchy, where we need to duplicate each cgroup in each * hierarchy that shall be enabled for it. */ own_mask = unit_get_own_mask(u); if (own_mask & CGROUP_MASK_BPF_FIREWALL & ~u->manager->cgroup_supported) emit_bpf_firewall_warning(u); mask = own_mask | unit_get_members_mask(u) | unit_get_siblings_mask(u); mask &= u->manager->cgroup_supported; mask &= ~unit_get_ancestor_disable_mask(u); return mask; } CGroupMask unit_get_enable_mask(Unit *u) { CGroupMask mask; /* This returns the cgroup mask of all controllers to enable * for the children of a specific cgroup. This is primarily * useful for the unified cgroup hierarchy, where each cgroup * controls which controllers are enabled for its children. */ mask = unit_get_members_mask(u); mask &= u->manager->cgroup_supported; mask &= ~unit_get_ancestor_disable_mask(u); return mask; } void unit_invalidate_cgroup_members_masks(Unit *u) { Unit *slice; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return; /* Recurse invalidate the member masks cache all the way up the tree */ crt->cgroup_members_mask_valid = false; slice = UNIT_GET_SLICE(u); if (slice) unit_invalidate_cgroup_members_masks(slice); } const char *unit_get_realized_cgroup_path(Unit *u, CGroupMask mask) { /* Returns the realized cgroup path of the specified unit where all specified controllers are available. */ while (u) { CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (crt && crt->cgroup_path && crt->cgroup_realized && FLAGS_SET(crt->cgroup_realized_mask, mask)) return crt->cgroup_path; u = UNIT_GET_SLICE(u); } return NULL; } static const char *migrate_callback(CGroupMask mask, void *userdata) { /* If not realized at all, migrate to root (""). * It may happen if we're upgrading from older version that didn't clean up. */ return strempty(unit_get_realized_cgroup_path(userdata, mask)); } int unit_default_cgroup_path(const Unit *u, char **ret) { _cleanup_free_ char *p = NULL; int r; assert(u); assert(ret); if (unit_has_name(u, SPECIAL_ROOT_SLICE)) p = strdup(u->manager->cgroup_root); else { _cleanup_free_ char *escaped = NULL, *slice_path = NULL; Unit *slice; slice = UNIT_GET_SLICE(u); if (slice && !unit_has_name(slice, SPECIAL_ROOT_SLICE)) { r = cg_slice_to_path(slice->id, &slice_path); if (r < 0) return r; } r = cg_escape(u->id, &escaped); if (r < 0) return r; p = path_join(empty_to_root(u->manager->cgroup_root), slice_path, escaped); } if (!p) return -ENOMEM; *ret = TAKE_PTR(p); return 0; } int unit_set_cgroup_path(Unit *u, const char *path) { _cleanup_free_ char *p = NULL; CGroupRuntime *crt; int r; assert(u); crt = unit_get_cgroup_runtime(u); if (crt && streq_ptr(crt->cgroup_path, path)) return 0; unit_release_cgroup(u, /* drop_cgroup_runtime = */ true); crt = unit_setup_cgroup_runtime(u); if (!crt) return -ENOMEM; if (path) { p = strdup(path); if (!p) return -ENOMEM; r = hashmap_put(u->manager->cgroup_unit, p, u); if (r < 0) return r; } assert(!crt->cgroup_path); crt->cgroup_path = TAKE_PTR(p); return 1; } int unit_watch_cgroup(Unit *u) { _cleanup_free_ char *events = NULL; int r; assert(u); /* Watches the "cgroups.events" attribute of this unit's cgroup for "empty" events, but only if * cgroupv2 is available. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return 0; if (crt->cgroup_control_inotify_wd >= 0) return 0; /* Only applies to the unified hierarchy */ r = cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER); if (r < 0) return log_error_errno(r, "Failed to determine whether the name=systemd hierarchy is unified: %m"); if (r == 0) return 0; /* No point in watch the top-level slice, it's never going to run empty. */ if (unit_has_name(u, SPECIAL_ROOT_SLICE)) return 0; r = hashmap_ensure_allocated(&u->manager->cgroup_control_inotify_wd_unit, &trivial_hash_ops); if (r < 0) return log_oom(); r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, "cgroup.events", &events); if (r < 0) return log_oom(); crt->cgroup_control_inotify_wd = inotify_add_watch(u->manager->cgroup_inotify_fd, events, IN_MODIFY); if (crt->cgroup_control_inotify_wd < 0) { if (errno == ENOENT) /* If the directory is already gone we don't need to track it, so this * is not an error */ return 0; return log_unit_error_errno(u, errno, "Failed to add control inotify watch descriptor for control group %s: %m", empty_to_root(crt->cgroup_path)); } r = hashmap_put(u->manager->cgroup_control_inotify_wd_unit, INT_TO_PTR(crt->cgroup_control_inotify_wd), u); if (r < 0) return log_unit_error_errno(u, r, "Failed to add control inotify watch descriptor for control group %s to hash map: %m", empty_to_root(crt->cgroup_path)); return 0; } int unit_watch_cgroup_memory(Unit *u) { _cleanup_free_ char *events = NULL; int r; assert(u); /* Watches the "memory.events" attribute of this unit's cgroup for "oom_kill" events, but only if * cgroupv2 is available. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return 0; CGroupContext *c = unit_get_cgroup_context(u); if (!c) return 0; /* The "memory.events" attribute is only available if the memory controller is on. Let's hence tie * this to memory accounting, in a way watching for OOM kills is a form of memory accounting after * all. */ if (!c->memory_accounting) return 0; /* Don't watch inner nodes, as the kernel doesn't report oom_kill events recursively currently, and * we also don't want to generate a log message for each parent cgroup of a process. */ if (u->type == UNIT_SLICE) return 0; if (crt->cgroup_memory_inotify_wd >= 0) return 0; /* Only applies to the unified hierarchy */ r = cg_all_unified(); if (r < 0) return log_error_errno(r, "Failed to determine whether the memory controller is unified: %m"); if (r == 0) return 0; r = hashmap_ensure_allocated(&u->manager->cgroup_memory_inotify_wd_unit, &trivial_hash_ops); if (r < 0) return log_oom(); r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, "memory.events", &events); if (r < 0) return log_oom(); crt->cgroup_memory_inotify_wd = inotify_add_watch(u->manager->cgroup_inotify_fd, events, IN_MODIFY); if (crt->cgroup_memory_inotify_wd < 0) { if (errno == ENOENT) /* If the directory is already gone we don't need to track it, so this * is not an error */ return 0; return log_unit_error_errno(u, errno, "Failed to add memory inotify watch descriptor for control group %s: %m", empty_to_root(crt->cgroup_path)); } r = hashmap_put(u->manager->cgroup_memory_inotify_wd_unit, INT_TO_PTR(crt->cgroup_memory_inotify_wd), u); if (r < 0) return log_unit_error_errno(u, r, "Failed to add memory inotify watch descriptor for control group %s to hash map: %m", empty_to_root(crt->cgroup_path)); return 0; } int unit_pick_cgroup_path(Unit *u) { _cleanup_free_ char *path = NULL; int r; assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return -EINVAL; CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) return -ENOMEM; if (crt->cgroup_path) return 0; r = unit_default_cgroup_path(u, &path); if (r < 0) return log_unit_error_errno(u, r, "Failed to generate default cgroup path: %m"); r = unit_set_cgroup_path(u, path); if (r == -EEXIST) return log_unit_error_errno(u, r, "Control group %s exists already.", empty_to_root(path)); if (r < 0) return log_unit_error_errno(u, r, "Failed to set unit's control group path to %s: %m", empty_to_root(path)); return 0; } static int unit_update_cgroup( Unit *u, CGroupMask target_mask, CGroupMask enable_mask, ManagerState state) { bool created, is_root_slice; CGroupMask migrate_mask = 0; _cleanup_free_ char *cgroup_full_path = NULL; int r; assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return 0; if (u->freezer_state != FREEZER_RUNNING) return log_unit_error_errno(u, SYNTHETIC_ERRNO(EBUSY), "Cannot realize cgroup for frozen unit."); /* Figure out our cgroup path */ r = unit_pick_cgroup_path(u); if (r < 0) return r; CGroupRuntime *crt = ASSERT_PTR(unit_get_cgroup_runtime(u)); /* First, create our own group */ r = cg_create_everywhere(u->manager->cgroup_supported, target_mask, crt->cgroup_path); if (r < 0) return log_unit_error_errno(u, r, "Failed to create cgroup %s: %m", empty_to_root(crt->cgroup_path)); created = r; if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) > 0) { uint64_t cgroup_id = 0; r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, NULL, &cgroup_full_path); if (r == 0) { r = cg_path_get_cgroupid(cgroup_full_path, &cgroup_id); if (r < 0) log_unit_full_errno(u, ERRNO_IS_NOT_SUPPORTED(r) ? LOG_DEBUG : LOG_WARNING, r, "Failed to get cgroup ID of cgroup %s, ignoring: %m", cgroup_full_path); } else log_unit_warning_errno(u, r, "Failed to get full cgroup path on cgroup %s, ignoring: %m", empty_to_root(crt->cgroup_path)); crt->cgroup_id = cgroup_id; } /* Start watching it */ (void) unit_watch_cgroup(u); (void) unit_watch_cgroup_memory(u); /* For v2 we preserve enabled controllers in delegated units, adjust others, * for v1 we figure out which controller hierarchies need migration. */ if (created || !crt->cgroup_realized || !unit_cgroup_delegate(u)) { CGroupMask result_mask = 0; /* Enable all controllers we need */ r = cg_enable_everywhere(u->manager->cgroup_supported, enable_mask, crt->cgroup_path, &result_mask); if (r < 0) log_unit_warning_errno(u, r, "Failed to enable/disable controllers on cgroup %s, ignoring: %m", empty_to_root(crt->cgroup_path)); /* Remember what's actually enabled now */ crt->cgroup_enabled_mask = result_mask; migrate_mask = crt->cgroup_realized_mask ^ target_mask; } /* Keep track that this is now realized */ crt->cgroup_realized = true; crt->cgroup_realized_mask = target_mask; /* Migrate processes in controller hierarchies both downwards (enabling) and upwards (disabling). * * Unnecessary controller cgroups are trimmed (after emptied by upward migration). * We perform migration also with whole slices for cases when users don't care about leave * granularity. Since delegated_mask is subset of target mask, we won't trim slice subtree containing * delegated units. */ if (cg_all_unified() == 0) { r = cg_migrate_v1_controllers(u->manager->cgroup_supported, migrate_mask, crt->cgroup_path, migrate_callback, u); if (r < 0) log_unit_warning_errno(u, r, "Failed to migrate controller cgroups from %s, ignoring: %m", empty_to_root(crt->cgroup_path)); is_root_slice = unit_has_name(u, SPECIAL_ROOT_SLICE); r = cg_trim_v1_controllers(u->manager->cgroup_supported, ~target_mask, crt->cgroup_path, !is_root_slice); if (r < 0) log_unit_warning_errno(u, r, "Failed to delete controller cgroups %s, ignoring: %m", empty_to_root(crt->cgroup_path)); } /* Set attributes */ cgroup_context_apply(u, target_mask, state); cgroup_xattr_apply(u); /* For most units we expect that memory monitoring is set up before the unit is started and we won't * touch it after. For PID 1 this is different though, because we couldn't possibly do that given * that PID 1 runs before init.scope is even set up. Hence, whenever init.scope is realized, let's * try to open the memory pressure interface anew. */ if (unit_has_name(u, SPECIAL_INIT_SCOPE)) (void) manager_setup_memory_pressure_event_source(u->manager); return 0; } static int unit_attach_pid_to_cgroup_via_bus(Unit *u, pid_t pid, const char *suffix_path) { _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; char *pp; int r; assert(u); if (MANAGER_IS_SYSTEM(u->manager)) return -EINVAL; if (!u->manager->system_bus) return -EIO; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; /* Determine this unit's cgroup path relative to our cgroup root */ pp = path_startswith(crt->cgroup_path, u->manager->cgroup_root); if (!pp) return -EINVAL; pp = strjoina("/", pp, suffix_path); path_simplify(pp); r = bus_call_method(u->manager->system_bus, bus_systemd_mgr, "AttachProcessesToUnit", &error, NULL, "ssau", NULL /* empty unit name means client's unit, i.e. us */, pp, 1, (uint32_t) pid); if (r < 0) return log_unit_debug_errno(u, r, "Failed to attach unit process " PID_FMT " via the bus: %s", pid, bus_error_message(&error, r)); return 0; } int unit_attach_pids_to_cgroup(Unit *u, Set *pids, const char *suffix_path) { _cleanup_free_ char *joined = NULL; CGroupMask delegated_mask; const char *p; PidRef *pid; int ret, r; assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return -EINVAL; if (set_isempty(pids)) return 0; /* Load any custom firewall BPF programs here once to test if they are existing and actually loadable. * Fail here early since later errors in the call chain unit_realize_cgroup to cgroup_context_apply are ignored. */ r = bpf_firewall_load_custom(u); if (r < 0) return r; r = unit_realize_cgroup(u); if (r < 0) return r; CGroupRuntime *crt = ASSERT_PTR(unit_get_cgroup_runtime(u)); if (isempty(suffix_path)) p = crt->cgroup_path; else { joined = path_join(crt->cgroup_path, suffix_path); if (!joined) return -ENOMEM; p = joined; } delegated_mask = unit_get_delegate_mask(u); ret = 0; SET_FOREACH(pid, pids) { /* Unfortunately we cannot add pids by pidfd to a cgroup. Hence we have to use PIDs instead, * which of course is racy. Let's shorten the race a bit though, and re-validate the PID * before we use it */ r = pidref_verify(pid); if (r < 0) { log_unit_info_errno(u, r, "PID " PID_FMT " vanished before we could move it to target cgroup '%s', skipping: %m", pid->pid, empty_to_root(p)); continue; } /* First, attach the PID to the main cgroup hierarchy */ r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, p, pid->pid); if (r < 0) { bool again = MANAGER_IS_USER(u->manager) && ERRNO_IS_PRIVILEGE(r); log_unit_full_errno(u, again ? LOG_DEBUG : LOG_INFO, r, "Couldn't move process "PID_FMT" to%s requested cgroup '%s': %m", pid->pid, again ? " directly" : "", empty_to_root(p)); if (again) { int z; /* If we are in a user instance, and we can't move the process ourselves due * to permission problems, let's ask the system instance about it instead. * Since it's more privileged it might be able to move the process across the * leaves of a subtree whose top node is not owned by us. */ z = unit_attach_pid_to_cgroup_via_bus(u, pid->pid, suffix_path); if (z < 0) log_unit_info_errno(u, z, "Couldn't move process "PID_FMT" to requested cgroup '%s' (directly or via the system bus): %m", pid->pid, empty_to_root(p)); else { if (ret >= 0) ret++; /* Count successful additions */ continue; /* When the bus thing worked via the bus we are fully done for this PID. */ } } if (ret >= 0) ret = r; /* Remember first error */ continue; } else if (ret >= 0) ret++; /* Count successful additions */ r = cg_all_unified(); if (r < 0) return r; if (r > 0) continue; /* In the legacy hierarchy, attach the process to the request cgroup if possible, and if not to the * innermost realized one */ for (CGroupController c = 0; c < _CGROUP_CONTROLLER_MAX; c++) { CGroupMask bit = CGROUP_CONTROLLER_TO_MASK(c); const char *realized; if (!(u->manager->cgroup_supported & bit)) continue; /* If this controller is delegated and realized, honour the caller's request for the cgroup suffix. */ if (delegated_mask & crt->cgroup_realized_mask & bit) { r = cg_attach(cgroup_controller_to_string(c), p, pid->pid); if (r >= 0) continue; /* Success! */ log_unit_debug_errno(u, r, "Failed to attach PID " PID_FMT " to requested cgroup %s in controller %s, falling back to unit's cgroup: %m", pid->pid, empty_to_root(p), cgroup_controller_to_string(c)); } /* So this controller is either not delegate or realized, or something else weird happened. In * that case let's attach the PID at least to the closest cgroup up the tree that is * realized. */ realized = unit_get_realized_cgroup_path(u, bit); if (!realized) continue; /* Not even realized in the root slice? Then let's not bother */ r = cg_attach(cgroup_controller_to_string(c), realized, pid->pid); if (r < 0) log_unit_debug_errno(u, r, "Failed to attach PID " PID_FMT " to realized cgroup %s in controller %s, ignoring: %m", pid->pid, realized, cgroup_controller_to_string(c)); } } return ret; } static bool unit_has_mask_realized( Unit *u, CGroupMask target_mask, CGroupMask enable_mask) { assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return false; /* Returns true if this unit is fully realized. We check four things: * * 1. Whether the cgroup was created at all * 2. Whether the cgroup was created in all the hierarchies we need it to be created in (in case of cgroup v1) * 3. Whether the cgroup has all the right controllers enabled (in case of cgroup v2) * 4. Whether the invalidation mask is currently zero * * If you wonder why we mask the target realization and enable mask with CGROUP_MASK_V1/CGROUP_MASK_V2: note * that there are three sets of bitmasks: CGROUP_MASK_V1 (for real cgroup v1 controllers), CGROUP_MASK_V2 (for * real cgroup v2 controllers) and CGROUP_MASK_BPF (for BPF-based pseudo-controllers). Now, cgroup_realized_mask * is only matters for cgroup v1 controllers, and cgroup_enabled_mask only used for cgroup v2, and if they * differ in the others, we don't really care. (After all, the cgroup_enabled_mask tracks with controllers are * enabled through cgroup.subtree_control, and since the BPF pseudo-controllers don't show up there, they * simply don't matter. */ return crt->cgroup_realized && ((crt->cgroup_realized_mask ^ target_mask) & CGROUP_MASK_V1) == 0 && ((crt->cgroup_enabled_mask ^ enable_mask) & CGROUP_MASK_V2) == 0 && crt->cgroup_invalidated_mask == 0; } static bool unit_has_mask_disables_realized( Unit *u, CGroupMask target_mask, CGroupMask enable_mask) { assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return true; /* Returns true if all controllers which should be disabled are indeed disabled. * * Unlike unit_has_mask_realized, we don't care what was enabled, only that anything we want to remove is * already removed. */ return !crt->cgroup_realized || (FLAGS_SET(crt->cgroup_realized_mask, target_mask & CGROUP_MASK_V1) && FLAGS_SET(crt->cgroup_enabled_mask, enable_mask & CGROUP_MASK_V2)); } static bool unit_has_mask_enables_realized( Unit *u, CGroupMask target_mask, CGroupMask enable_mask) { assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return false; /* Returns true if all controllers which should be enabled are indeed enabled. * * Unlike unit_has_mask_realized, we don't care about the controllers that are not present, only that anything * we want to add is already added. */ return crt->cgroup_realized && ((crt->cgroup_realized_mask | target_mask) & CGROUP_MASK_V1) == (crt->cgroup_realized_mask & CGROUP_MASK_V1) && ((crt->cgroup_enabled_mask | enable_mask) & CGROUP_MASK_V2) == (crt->cgroup_enabled_mask & CGROUP_MASK_V2); } void unit_add_to_cgroup_realize_queue(Unit *u) { assert(u); if (u->in_cgroup_realize_queue) return; LIST_APPEND(cgroup_realize_queue, u->manager->cgroup_realize_queue, u); u->in_cgroup_realize_queue = true; } static void unit_remove_from_cgroup_realize_queue(Unit *u) { assert(u); if (!u->in_cgroup_realize_queue) return; LIST_REMOVE(cgroup_realize_queue, u->manager->cgroup_realize_queue, u); u->in_cgroup_realize_queue = false; } /* Controllers can only be enabled breadth-first, from the root of the * hierarchy downwards to the unit in question. */ static int unit_realize_cgroup_now_enable(Unit *u, ManagerState state) { CGroupMask target_mask, enable_mask, new_target_mask, new_enable_mask; Unit *slice; int r; assert(u); /* First go deal with this unit's parent, or we won't be able to enable * any new controllers at this layer. */ slice = UNIT_GET_SLICE(u); if (slice) { r = unit_realize_cgroup_now_enable(slice, state); if (r < 0) return r; } target_mask = unit_get_target_mask(u); enable_mask = unit_get_enable_mask(u); /* We can only enable in this direction, don't try to disable anything. */ if (unit_has_mask_enables_realized(u, target_mask, enable_mask)) return 0; CGroupRuntime *crt = unit_get_cgroup_runtime(u); new_target_mask = (crt ? crt->cgroup_realized_mask : 0) | target_mask; new_enable_mask = (crt ? crt->cgroup_enabled_mask : 0) | enable_mask; return unit_update_cgroup(u, new_target_mask, new_enable_mask, state); } /* Controllers can only be disabled depth-first, from the leaves of the * hierarchy upwards to the unit in question. */ static int unit_realize_cgroup_now_disable(Unit *u, ManagerState state) { Unit *m; assert(u); if (u->type != UNIT_SLICE) return 0; UNIT_FOREACH_DEPENDENCY(m, u, UNIT_ATOM_SLICE_OF) { CGroupMask target_mask, enable_mask, new_target_mask, new_enable_mask; int r; CGroupRuntime *rt = unit_get_cgroup_runtime(m); if (!rt) continue; /* The cgroup for this unit might not actually be fully realised yet, in which case it isn't * holding any controllers open anyway. */ if (!rt->cgroup_realized) continue; /* We must disable those below us first in order to release the controller. */ if (m->type == UNIT_SLICE) (void) unit_realize_cgroup_now_disable(m, state); target_mask = unit_get_target_mask(m); enable_mask = unit_get_enable_mask(m); /* We can only disable in this direction, don't try to enable anything. */ if (unit_has_mask_disables_realized(m, target_mask, enable_mask)) continue; new_target_mask = rt->cgroup_realized_mask & target_mask; new_enable_mask = rt->cgroup_enabled_mask & enable_mask; r = unit_update_cgroup(m, new_target_mask, new_enable_mask, state); if (r < 0) return r; } return 0; } /* Check if necessary controllers and attributes for a unit are in place. * * - If so, do nothing. * - If not, create paths, move processes over, and set attributes. * * Controllers can only be *enabled* in a breadth-first way, and *disabled* in * a depth-first way. As such the process looks like this: * * Suppose we have a cgroup hierarchy which looks like this: * * root * / \ * / \ * / \ * a b * / \ / \ * / \ / \ * c d e f * / \ / \ / \ / \ * h i j k l m n o * * 1. We want to realise cgroup "d" now. * 2. cgroup "a" has DisableControllers=cpu in the associated unit. * 3. cgroup "k" just started requesting the memory controller. * * To make this work we must do the following in order: * * 1. Disable CPU controller in k, j * 2. Disable CPU controller in d * 3. Enable memory controller in root * 4. Enable memory controller in a * 5. Enable memory controller in d * 6. Enable memory controller in k * * Notice that we need to touch j in one direction, but not the other. We also * don't go beyond d when disabling -- it's up to "a" to get realized if it * wants to disable further. The basic rules are therefore: * * - If you're disabling something, you need to realise all of the cgroups from * your recursive descendants to the root. This starts from the leaves. * - If you're enabling something, you need to realise from the root cgroup * downwards, but you don't need to iterate your recursive descendants. * * Returns 0 on success and < 0 on failure. */ static int unit_realize_cgroup_now(Unit *u, ManagerState state) { CGroupMask target_mask, enable_mask; Unit *slice; int r; assert(u); unit_remove_from_cgroup_realize_queue(u); target_mask = unit_get_target_mask(u); enable_mask = unit_get_enable_mask(u); if (unit_has_mask_realized(u, target_mask, enable_mask)) return 0; /* Disable controllers below us, if there are any */ r = unit_realize_cgroup_now_disable(u, state); if (r < 0) return r; /* Enable controllers above us, if there are any */ slice = UNIT_GET_SLICE(u); if (slice) { r = unit_realize_cgroup_now_enable(slice, state); if (r < 0) return r; } /* Now actually deal with the cgroup we were trying to realise and set attributes */ r = unit_update_cgroup(u, target_mask, enable_mask, state); if (r < 0) return r; CGroupRuntime *crt = ASSERT_PTR(unit_get_cgroup_runtime(u)); /* Now, reset the invalidation mask */ crt->cgroup_invalidated_mask = 0; return 0; } unsigned manager_dispatch_cgroup_realize_queue(Manager *m) { ManagerState state; unsigned n = 0; Unit *i; int r; assert(m); state = manager_state(m); while ((i = m->cgroup_realize_queue)) { assert(i->in_cgroup_realize_queue); if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(i))) { /* Maybe things changed, and the unit is not actually active anymore? */ unit_remove_from_cgroup_realize_queue(i); continue; } r = unit_realize_cgroup_now(i, state); if (r < 0) log_warning_errno(r, "Failed to realize cgroups for queued unit %s, ignoring: %m", i->id); n++; } return n; } void unit_add_family_to_cgroup_realize_queue(Unit *u) { assert(u); assert(u->type == UNIT_SLICE); /* Family of a unit for is defined as (immediate) children of the unit and immediate children of all * its ancestors. * * Ideally we would enqueue ancestor path only (bottom up). However, on cgroup-v1 scheduling becomes * very weird if two units that own processes reside in the same slice, but one is realized in the * "cpu" hierarchy and one is not (for example because one has CPUWeight= set and the other does * not), because that means individual processes need to be scheduled against whole cgroups. Let's * avoid this asymmetry by always ensuring that siblings of a unit are always realized in their v1 * controller hierarchies too (if unit requires the controller to be realized). * * The function must invalidate cgroup_members_mask of all ancestors in order to calculate up to date * masks. */ do { CGroupRuntime *crt = unit_get_cgroup_runtime(u); /* Children of u likely changed when we're called */ if (crt) crt->cgroup_members_mask_valid = false; Unit *m; UNIT_FOREACH_DEPENDENCY(m, u, UNIT_ATOM_SLICE_OF) { /* No point in doing cgroup application for units without active processes. */ if (UNIT_IS_INACTIVE_OR_FAILED(unit_active_state(m))) continue; /* We only enqueue siblings if they were realized once at least, in the main * hierarchy. */ crt = unit_get_cgroup_runtime(m); if (!crt || !crt->cgroup_realized) continue; /* If the unit doesn't need any new controllers and has current ones * realized, it doesn't need any changes. */ if (unit_has_mask_realized(m, unit_get_target_mask(m), unit_get_enable_mask(m))) continue; unit_add_to_cgroup_realize_queue(m); } /* Parent comes after children */ unit_add_to_cgroup_realize_queue(u); u = UNIT_GET_SLICE(u); } while (u); } int unit_realize_cgroup(Unit *u) { Unit *slice; assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return 0; /* So, here's the deal: when realizing the cgroups for this unit, we need to first create all * parents, but there's more actually: for the weight-based controllers we also need to make sure * that all our siblings (i.e. units that are in the same slice as we are) have cgroups, too. On the * other hand, when a controller is removed from realized set, it may become unnecessary in siblings * and ancestors and they should be (de)realized too. * * This call will defer work on the siblings and derealized ancestors to the next event loop * iteration and synchronously creates the parent cgroups (unit_realize_cgroup_now). */ slice = UNIT_GET_SLICE(u); if (slice) unit_add_family_to_cgroup_realize_queue(slice); /* And realize this one now (and apply the values) */ return unit_realize_cgroup_now(u, manager_state(u->manager)); } void unit_release_cgroup(Unit *u, bool drop_cgroup_runtime) { assert(u); /* Forgets all cgroup details for this cgroup — but does *not* destroy the cgroup. This is hence OK to call * when we close down everything for reexecution, where we really want to leave the cgroup in place. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return; if (crt->cgroup_path) { (void) hashmap_remove(u->manager->cgroup_unit, crt->cgroup_path); crt->cgroup_path = mfree(crt->cgroup_path); } if (crt->cgroup_control_inotify_wd >= 0) { if (inotify_rm_watch(u->manager->cgroup_inotify_fd, crt->cgroup_control_inotify_wd) < 0) log_unit_debug_errno(u, errno, "Failed to remove cgroup control inotify watch %i for %s, ignoring: %m", crt->cgroup_control_inotify_wd, u->id); (void) hashmap_remove(u->manager->cgroup_control_inotify_wd_unit, INT_TO_PTR(crt->cgroup_control_inotify_wd)); crt->cgroup_control_inotify_wd = -1; } if (crt->cgroup_memory_inotify_wd >= 0) { if (inotify_rm_watch(u->manager->cgroup_inotify_fd, crt->cgroup_memory_inotify_wd) < 0) log_unit_debug_errno(u, errno, "Failed to remove cgroup memory inotify watch %i for %s, ignoring: %m", crt->cgroup_memory_inotify_wd, u->id); (void) hashmap_remove(u->manager->cgroup_memory_inotify_wd_unit, INT_TO_PTR(crt->cgroup_memory_inotify_wd)); crt->cgroup_memory_inotify_wd = -1; } if (drop_cgroup_runtime) *(CGroupRuntime**) ((uint8_t*) u + UNIT_VTABLE(u)->cgroup_runtime_offset) = cgroup_runtime_free(crt); } int unit_cgroup_is_empty(Unit *u) { int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return -ENXIO; if (!crt->cgroup_path) return -EOWNERDEAD; r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path); if (r < 0) return log_unit_debug_errno(u, r, "Failed to determine whether cgroup %s is empty, ignoring: %m", empty_to_root(crt->cgroup_path)); return r; } static bool unit_maybe_release_cgroup(Unit *u) { int r; /* Releases the cgroup only if it is recursively empty. * Returns true if the cgroup was released, false otherwise. */ assert(u); /* Don't release the cgroup if there are still processes under it. If we get notified later when all * the processes exit (e.g. the processes were in D-state and exited after the unit was marked as * failed) we need the cgroup paths to continue to be tracked by the manager so they can be looked up * and cleaned up later. */ r = unit_cgroup_is_empty(u); if (r > 0) { /* Do not free CGroupRuntime when called from unit_prune_cgroup. Various accounting data * we should keep, especially CPU usage and *_peak ones which would be shown even after * the unit stops. */ unit_release_cgroup(u, /* drop_cgroup_runtime = */ false); return true; } return false; } void unit_prune_cgroup(Unit *u) { bool is_root_slice; int r; assert(u); /* Removes the cgroup, if empty and possible, and stops watching it. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; /* Cache the last CPU and memory usage values before we destroy the cgroup */ (void) unit_get_cpu_usage(u, /* ret = */ NULL); for (CGroupMemoryAccountingMetric metric = 0; metric <= _CGROUP_MEMORY_ACCOUNTING_METRIC_CACHED_LAST; metric++) (void) unit_get_memory_accounting(u, metric, /* ret = */ NULL); #if BPF_FRAMEWORK (void) bpf_restrict_fs_cleanup(u); /* Remove cgroup from the global LSM BPF map */ #endif unit_modify_nft_set(u, /* add = */ false); is_root_slice = unit_has_name(u, SPECIAL_ROOT_SLICE); r = cg_trim_everywhere(u->manager->cgroup_supported, crt->cgroup_path, !is_root_slice); if (r < 0) /* One reason we could have failed here is, that the cgroup still contains a process. * However, if the cgroup becomes removable at a later time, it might be removed when * the containing slice is stopped. So even if we failed now, this unit shouldn't assume * that the cgroup is still realized the next time it is started. Do not return early * on error, continue cleanup. */ log_unit_full_errno(u, r == -EBUSY ? LOG_DEBUG : LOG_WARNING, r, "Failed to destroy cgroup %s, ignoring: %m", empty_to_root(crt->cgroup_path)); if (is_root_slice) return; if (!unit_maybe_release_cgroup(u)) /* Returns true if the cgroup was released */ return; assert(crt == unit_get_cgroup_runtime(u)); assert(!crt->cgroup_path); crt->cgroup_realized = false; crt->cgroup_realized_mask = 0; crt->cgroup_enabled_mask = 0; crt->bpf_device_control_installed = bpf_program_free(crt->bpf_device_control_installed); } int unit_search_main_pid(Unit *u, PidRef *ret) { _cleanup_(pidref_done) PidRef pidref = PIDREF_NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(u); assert(ret); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENXIO; r = cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, &f); if (r < 0) return r; for (;;) { _cleanup_(pidref_done) PidRef npidref = PIDREF_NULL; /* cg_read_pidref() will return an error on unmapped PIDs. * We can't reasonably deal with units that contain those. */ r = cg_read_pidref(f, &npidref, CGROUP_DONT_SKIP_UNMAPPED); if (r < 0) return r; if (r == 0) break; if (pidref_equal(&pidref, &npidref)) /* seen already, cgroupfs reports duplicates! */ continue; if (pidref_is_my_child(&npidref) <= 0) /* ignore processes further down the tree */ continue; if (pidref_is_set(&pidref) != 0) /* Dang, there's more than one daemonized PID in this group, so we don't know what * process is the main process. */ return -ENODATA; pidref = TAKE_PIDREF(npidref); } if (!pidref_is_set(&pidref)) return -ENODATA; *ret = TAKE_PIDREF(pidref); return 0; } static int unit_watch_pids_in_path(Unit *u, const char *path) { _cleanup_closedir_ DIR *d = NULL; _cleanup_fclose_ FILE *f = NULL; int ret = 0, r; assert(u); assert(path); r = cg_enumerate_processes(SYSTEMD_CGROUP_CONTROLLER, path, &f); if (r < 0) RET_GATHER(ret, r); else { for (;;) { _cleanup_(pidref_done) PidRef pid = PIDREF_NULL; r = cg_read_pidref(f, &pid, /* flags = */ 0); if (r == 0) break; if (r < 0) { RET_GATHER(ret, r); break; } RET_GATHER(ret, unit_watch_pidref(u, &pid, /* exclusive= */ false)); } } r = cg_enumerate_subgroups(SYSTEMD_CGROUP_CONTROLLER, path, &d); if (r < 0) RET_GATHER(ret, r); else { for (;;) { _cleanup_free_ char *fn = NULL, *p = NULL; r = cg_read_subgroup(d, &fn); if (r == 0) break; if (r < 0) { RET_GATHER(ret, r); break; } p = path_join(empty_to_root(path), fn); if (!p) return -ENOMEM; RET_GATHER(ret, unit_watch_pids_in_path(u, p)); } } return ret; } int unit_synthesize_cgroup_empty_event(Unit *u) { int r; assert(u); /* Enqueue a synthetic cgroup empty event if this unit doesn't watch any PIDs anymore. This is compatibility * support for non-unified systems where notifications aren't reliable, and hence need to take whatever we can * get as notification source as soon as we stopped having any useful PIDs to watch for. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENOENT; r = cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER); if (r < 0) return r; if (r > 0) /* On unified we have reliable notifications, and don't need this */ return 0; if (!set_isempty(u->pids)) return 0; unit_add_to_cgroup_empty_queue(u); return 0; } int unit_watch_all_pids(Unit *u) { int r; assert(u); /* Adds all PIDs from our cgroup to the set of PIDs we * watch. This is a fallback logic for cases where we do not * get reliable cgroup empty notifications: we try to use * SIGCHLD as replacement. */ CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENOENT; r = cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER); if (r < 0) return r; if (r > 0) /* On unified we can use proper notifications */ return 0; return unit_watch_pids_in_path(u, crt->cgroup_path); } static int on_cgroup_empty_event(sd_event_source *s, void *userdata) { Manager *m = ASSERT_PTR(userdata); Unit *u; int r; assert(s); u = m->cgroup_empty_queue; if (!u) return 0; assert(u->in_cgroup_empty_queue); u->in_cgroup_empty_queue = false; LIST_REMOVE(cgroup_empty_queue, m->cgroup_empty_queue, u); if (m->cgroup_empty_queue) { /* More stuff queued, let's make sure we remain enabled */ r = sd_event_source_set_enabled(s, SD_EVENT_ONESHOT); if (r < 0) log_debug_errno(r, "Failed to reenable cgroup empty event source, ignoring: %m"); } /* Update state based on OOM kills before we notify about cgroup empty event */ (void) unit_check_oom(u); (void) unit_check_oomd_kill(u); unit_add_to_gc_queue(u); if (IN_SET(unit_active_state(u), UNIT_INACTIVE, UNIT_FAILED)) unit_prune_cgroup(u); else if (UNIT_VTABLE(u)->notify_cgroup_empty) UNIT_VTABLE(u)->notify_cgroup_empty(u); return 0; } void unit_add_to_cgroup_empty_queue(Unit *u) { int r; assert(u); /* Note that there are four different ways how cgroup empty events reach us: * * 1. On the unified hierarchy we get an inotify event on the cgroup * * 2. On the legacy hierarchy, when running in system mode, we get a datagram on the cgroup agent socket * * 3. On the legacy hierarchy, when running in user mode, we get a D-Bus signal on the system bus * * 4. On the legacy hierarchy, in service units we start watching all processes of the cgroup for SIGCHLD as * soon as we get one SIGCHLD, to deal with unreliable cgroup notifications. * * Regardless which way we got the notification, we'll verify it here, and then add it to a separate * queue. This queue will be dispatched at a lower priority than the SIGCHLD handler, so that we always use * SIGCHLD if we can get it first, and only use the cgroup empty notifications if there's no SIGCHLD pending * (which might happen if the cgroup doesn't contain processes that are our own child, which is typically the * case for scope units). */ if (u->in_cgroup_empty_queue) return; /* Let's verify that the cgroup is really empty */ r = unit_cgroup_is_empty(u); if (r <= 0) return; LIST_PREPEND(cgroup_empty_queue, u->manager->cgroup_empty_queue, u); u->in_cgroup_empty_queue = true; /* Trigger the defer event */ r = sd_event_source_set_enabled(u->manager->cgroup_empty_event_source, SD_EVENT_ONESHOT); if (r < 0) log_debug_errno(r, "Failed to enable cgroup empty event source: %m"); } static void unit_remove_from_cgroup_empty_queue(Unit *u) { assert(u); if (!u->in_cgroup_empty_queue) return; LIST_REMOVE(cgroup_empty_queue, u->manager->cgroup_empty_queue, u); u->in_cgroup_empty_queue = false; } int unit_check_oomd_kill(Unit *u) { _cleanup_free_ char *value = NULL; bool increased; uint64_t n = 0; int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return 0; r = cg_all_unified(); if (r < 0) return log_unit_debug_errno(u, r, "Couldn't determine whether we are in all unified mode: %m"); else if (r == 0) return 0; r = cg_get_xattr_malloc(crt->cgroup_path, "user.oomd_ooms", &value); if (r < 0 && !ERRNO_IS_XATTR_ABSENT(r)) return r; if (!isempty(value)) { r = safe_atou64(value, &n); if (r < 0) return r; } increased = n > crt->managed_oom_kill_last; crt->managed_oom_kill_last = n; if (!increased) return 0; n = 0; value = mfree(value); r = cg_get_xattr_malloc(crt->cgroup_path, "user.oomd_kill", &value); if (r >= 0 && !isempty(value)) (void) safe_atou64(value, &n); if (n > 0) log_unit_struct(u, LOG_NOTICE, "MESSAGE_ID=" SD_MESSAGE_UNIT_OOMD_KILL_STR, LOG_UNIT_INVOCATION_ID(u), LOG_UNIT_MESSAGE(u, "systemd-oomd killed %"PRIu64" process(es) in this unit.", n), "N_PROCESSES=%" PRIu64, n); else log_unit_struct(u, LOG_NOTICE, "MESSAGE_ID=" SD_MESSAGE_UNIT_OOMD_KILL_STR, LOG_UNIT_INVOCATION_ID(u), LOG_UNIT_MESSAGE(u, "systemd-oomd killed some process(es) in this unit.")); unit_notify_cgroup_oom(u, /* ManagedOOM= */ true); return 1; } int unit_check_oom(Unit *u) { _cleanup_free_ char *oom_kill = NULL; bool increased; uint64_t c; int r; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return 0; r = cg_get_keyed_attribute( "memory", crt->cgroup_path, "memory.events", STRV_MAKE("oom_kill"), &oom_kill); if (IN_SET(r, -ENOENT, -ENXIO)) /* Handle gracefully if cgroup or oom_kill attribute don't exist */ c = 0; else if (r < 0) return log_unit_debug_errno(u, r, "Failed to read oom_kill field of memory.events cgroup attribute: %m"); else { r = safe_atou64(oom_kill, &c); if (r < 0) return log_unit_debug_errno(u, r, "Failed to parse oom_kill field: %m"); } increased = c > crt->oom_kill_last; crt->oom_kill_last = c; if (!increased) return 0; log_unit_struct(u, LOG_NOTICE, "MESSAGE_ID=" SD_MESSAGE_UNIT_OUT_OF_MEMORY_STR, LOG_UNIT_INVOCATION_ID(u), LOG_UNIT_MESSAGE(u, "A process of this unit has been killed by the OOM killer.")); unit_notify_cgroup_oom(u, /* ManagedOOM= */ false); return 1; } static int on_cgroup_oom_event(sd_event_source *s, void *userdata) { Manager *m = ASSERT_PTR(userdata); Unit *u; int r; assert(s); u = m->cgroup_oom_queue; if (!u) return 0; assert(u->in_cgroup_oom_queue); u->in_cgroup_oom_queue = false; LIST_REMOVE(cgroup_oom_queue, m->cgroup_oom_queue, u); if (m->cgroup_oom_queue) { /* More stuff queued, let's make sure we remain enabled */ r = sd_event_source_set_enabled(s, SD_EVENT_ONESHOT); if (r < 0) log_debug_errno(r, "Failed to reenable cgroup oom event source, ignoring: %m"); } (void) unit_check_oom(u); unit_add_to_gc_queue(u); return 0; } static void unit_add_to_cgroup_oom_queue(Unit *u) { int r; assert(u); if (u->in_cgroup_oom_queue) return; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return; LIST_PREPEND(cgroup_oom_queue, u->manager->cgroup_oom_queue, u); u->in_cgroup_oom_queue = true; /* Trigger the defer event */ if (!u->manager->cgroup_oom_event_source) { _cleanup_(sd_event_source_unrefp) sd_event_source *s = NULL; r = sd_event_add_defer(u->manager->event, &s, on_cgroup_oom_event, u->manager); if (r < 0) { log_error_errno(r, "Failed to create cgroup oom event source: %m"); return; } r = sd_event_source_set_priority(s, EVENT_PRIORITY_CGROUP_OOM); if (r < 0) { log_error_errno(r, "Failed to set priority of cgroup oom event source: %m"); return; } (void) sd_event_source_set_description(s, "cgroup-oom"); u->manager->cgroup_oom_event_source = TAKE_PTR(s); } r = sd_event_source_set_enabled(u->manager->cgroup_oom_event_source, SD_EVENT_ONESHOT); if (r < 0) log_error_errno(r, "Failed to enable cgroup oom event source: %m"); } static int unit_check_cgroup_events(Unit *u) { char *values[2] = {}; int r; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return 0; r = cg_get_keyed_attribute_graceful( SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, "cgroup.events", STRV_MAKE("populated", "frozen"), values); if (r < 0) return r; /* The cgroup.events notifications can be merged together so act as we saw the given state for the * first time. The functions we call to handle given state are idempotent, which makes them * effectively remember the previous state. */ if (values[0]) { if (streq(values[0], "1")) unit_remove_from_cgroup_empty_queue(u); else unit_add_to_cgroup_empty_queue(u); } /* Disregard freezer state changes due to operations not initiated by us. * See: https://github.com/systemd/systemd/pull/13512/files#r416469963 and * https://github.com/systemd/systemd/pull/13512#issuecomment-573007207 */ if (values[1] && IN_SET(u->freezer_state, FREEZER_FREEZING, FREEZER_FREEZING_BY_PARENT, FREEZER_THAWING)) { if (streq(values[1], "0")) unit_thawed(u); else unit_frozen(u); } free(values[0]); free(values[1]); return 0; } static int on_cgroup_inotify_event(sd_event_source *s, int fd, uint32_t revents, void *userdata) { Manager *m = ASSERT_PTR(userdata); assert(s); assert(fd >= 0); for (;;) { union inotify_event_buffer buffer; ssize_t l; l = read(fd, &buffer, sizeof(buffer)); if (l < 0) { if (ERRNO_IS_TRANSIENT(errno)) return 0; return log_error_errno(errno, "Failed to read control group inotify events: %m"); } FOREACH_INOTIFY_EVENT_WARN(e, buffer, l) { Unit *u; if (e->wd < 0) /* Queue overflow has no watch descriptor */ continue; if (e->mask & IN_IGNORED) /* The watch was just removed */ continue; /* Note that inotify might deliver events for a watch even after it was removed, * because it was queued before the removal. Let's ignore this here safely. */ u = hashmap_get(m->cgroup_control_inotify_wd_unit, INT_TO_PTR(e->wd)); if (u) unit_check_cgroup_events(u); u = hashmap_get(m->cgroup_memory_inotify_wd_unit, INT_TO_PTR(e->wd)); if (u) unit_add_to_cgroup_oom_queue(u); } } } static int cg_bpf_mask_supported(CGroupMask *ret) { CGroupMask mask = 0; int r; /* BPF-based firewall */ r = bpf_firewall_supported(); if (r < 0) return r; if (r > 0) mask |= CGROUP_MASK_BPF_FIREWALL; /* BPF-based device access control */ r = bpf_devices_supported(); if (r < 0) return r; if (r > 0) mask |= CGROUP_MASK_BPF_DEVICES; /* BPF pinned prog */ r = bpf_foreign_supported(); if (r < 0) return r; if (r > 0) mask |= CGROUP_MASK_BPF_FOREIGN; /* BPF-based bind{4|6} hooks */ r = bpf_socket_bind_supported(); if (r < 0) return r; if (r > 0) mask |= CGROUP_MASK_BPF_SOCKET_BIND; /* BPF-based cgroup_skb/{egress|ingress} hooks */ r = bpf_restrict_ifaces_supported(); if (r < 0) return r; if (r > 0) mask |= CGROUP_MASK_BPF_RESTRICT_NETWORK_INTERFACES; *ret = mask; return 0; } int manager_setup_cgroup(Manager *m) { _cleanup_free_ char *path = NULL; const char *scope_path; int r, all_unified; CGroupMask mask; char *e; assert(m); /* 1. Determine hierarchy */ m->cgroup_root = mfree(m->cgroup_root); r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &m->cgroup_root); if (r < 0) return log_error_errno(r, "Cannot determine cgroup we are running in: %m"); /* Chop off the init scope, if we are already located in it */ e = endswith(m->cgroup_root, "/" SPECIAL_INIT_SCOPE); /* LEGACY: Also chop off the system slice if we are in * it. This is to support live upgrades from older systemd * versions where PID 1 was moved there. Also see * cg_get_root_path(). */ if (!e && MANAGER_IS_SYSTEM(m)) { e = endswith(m->cgroup_root, "/" SPECIAL_SYSTEM_SLICE); if (!e) e = endswith(m->cgroup_root, "/system"); /* even more legacy */ } if (e) *e = 0; /* And make sure to store away the root value without trailing slash, even for the root dir, so that we can * easily prepend it everywhere. */ delete_trailing_chars(m->cgroup_root, "/"); /* 2. Show data */ r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, NULL, &path); if (r < 0) return log_error_errno(r, "Cannot find cgroup mount point: %m"); r = cg_unified(); if (r < 0) return log_error_errno(r, "Couldn't determine if we are running in the unified hierarchy: %m"); all_unified = cg_all_unified(); if (all_unified < 0) return log_error_errno(all_unified, "Couldn't determine whether we are in all unified mode: %m"); if (all_unified > 0) log_debug("Unified cgroup hierarchy is located at %s.", path); else { r = cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER); if (r < 0) return log_error_errno(r, "Failed to determine whether systemd's own controller is in unified mode: %m"); if (r > 0) log_debug("Unified cgroup hierarchy is located at %s. Controllers are on legacy hierarchies.", path); else log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER_LEGACY ". File system hierarchy is at %s.", path); } /* 3. Allocate cgroup empty defer event source */ m->cgroup_empty_event_source = sd_event_source_disable_unref(m->cgroup_empty_event_source); r = sd_event_add_defer(m->event, &m->cgroup_empty_event_source, on_cgroup_empty_event, m); if (r < 0) return log_error_errno(r, "Failed to create cgroup empty event source: %m"); /* Schedule cgroup empty checks early, but after having processed service notification messages or * SIGCHLD signals, so that a cgroup running empty is always just the last safety net of * notification, and we collected the metadata the notification and SIGCHLD stuff offers first. */ r = sd_event_source_set_priority(m->cgroup_empty_event_source, EVENT_PRIORITY_CGROUP_EMPTY); if (r < 0) return log_error_errno(r, "Failed to set priority of cgroup empty event source: %m"); r = sd_event_source_set_enabled(m->cgroup_empty_event_source, SD_EVENT_OFF); if (r < 0) return log_error_errno(r, "Failed to disable cgroup empty event source: %m"); (void) sd_event_source_set_description(m->cgroup_empty_event_source, "cgroup-empty"); /* 4. Install notifier inotify object, or agent */ if (cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) > 0) { /* In the unified hierarchy we can get cgroup empty notifications via inotify. */ m->cgroup_inotify_event_source = sd_event_source_disable_unref(m->cgroup_inotify_event_source); safe_close(m->cgroup_inotify_fd); m->cgroup_inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC); if (m->cgroup_inotify_fd < 0) return log_error_errno(errno, "Failed to create control group inotify object: %m"); r = sd_event_add_io(m->event, &m->cgroup_inotify_event_source, m->cgroup_inotify_fd, EPOLLIN, on_cgroup_inotify_event, m); if (r < 0) return log_error_errno(r, "Failed to watch control group inotify object: %m"); /* Process cgroup empty notifications early. Note that when this event is dispatched it'll * just add the unit to a cgroup empty queue, hence let's run earlier than that. Also see * handling of cgroup agent notifications, for the classic cgroup hierarchy support. */ r = sd_event_source_set_priority(m->cgroup_inotify_event_source, EVENT_PRIORITY_CGROUP_INOTIFY); if (r < 0) return log_error_errno(r, "Failed to set priority of inotify event source: %m"); (void) sd_event_source_set_description(m->cgroup_inotify_event_source, "cgroup-inotify"); } else if (MANAGER_IS_SYSTEM(m) && manager_owns_host_root_cgroup(m) && !MANAGER_IS_TEST_RUN(m)) { /* On the legacy hierarchy we only get notifications via cgroup agents. (Which isn't really reliable, * since it does not generate events when control groups with children run empty. */ r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUPS_AGENT_PATH); if (r < 0) log_warning_errno(r, "Failed to install release agent, ignoring: %m"); else if (r > 0) log_debug("Installed release agent."); else if (r == 0) log_debug("Release agent already installed."); } /* 5. Make sure we are in the special "init.scope" unit in the root slice. */ scope_path = strjoina(m->cgroup_root, "/" SPECIAL_INIT_SCOPE); r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, scope_path, 0); if (r >= 0) { /* Also, move all other userspace processes remaining in the root cgroup into that scope. */ r = cg_migrate(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, SYSTEMD_CGROUP_CONTROLLER, scope_path, 0); if (r < 0) log_warning_errno(r, "Couldn't move remaining userspace processes, ignoring: %m"); /* 6. And pin it, so that it cannot be unmounted */ safe_close(m->pin_cgroupfs_fd); m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK); if (m->pin_cgroupfs_fd < 0) return log_error_errno(errno, "Failed to open pin file: %m"); } else if (!MANAGER_IS_TEST_RUN(m)) return log_error_errno(r, "Failed to create %s control group: %m", scope_path); /* 7. Always enable hierarchical support if it exists... */ if (!all_unified && !MANAGER_IS_TEST_RUN(m)) (void) cg_set_attribute("memory", "/", "memory.use_hierarchy", "1"); /* 8. Figure out which controllers are supported */ r = cg_mask_supported_subtree(m->cgroup_root, &m->cgroup_supported); if (r < 0) return log_error_errno(r, "Failed to determine supported controllers: %m"); /* 9. Figure out which bpf-based pseudo-controllers are supported */ r = cg_bpf_mask_supported(&mask); if (r < 0) return log_error_errno(r, "Failed to determine supported bpf-based pseudo-controllers: %m"); m->cgroup_supported |= mask; /* 10. Log which controllers are supported */ for (CGroupController c = 0; c < _CGROUP_CONTROLLER_MAX; c++) log_debug("Controller '%s' supported: %s", cgroup_controller_to_string(c), yes_no(m->cgroup_supported & CGROUP_CONTROLLER_TO_MASK(c))); return 0; } void manager_shutdown_cgroup(Manager *m, bool delete) { assert(m); /* We can't really delete the group, since we are in it. But * let's trim it. */ if (delete && m->cgroup_root && !FLAGS_SET(m->test_run_flags, MANAGER_TEST_RUN_MINIMAL)) (void) cg_trim(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_root, false); m->cgroup_empty_event_source = sd_event_source_disable_unref(m->cgroup_empty_event_source); m->cgroup_control_inotify_wd_unit = hashmap_free(m->cgroup_control_inotify_wd_unit); m->cgroup_memory_inotify_wd_unit = hashmap_free(m->cgroup_memory_inotify_wd_unit); m->cgroup_inotify_event_source = sd_event_source_disable_unref(m->cgroup_inotify_event_source); m->cgroup_inotify_fd = safe_close(m->cgroup_inotify_fd); m->pin_cgroupfs_fd = safe_close(m->pin_cgroupfs_fd); m->cgroup_root = mfree(m->cgroup_root); } Unit* manager_get_unit_by_cgroup(Manager *m, const char *cgroup) { char *p; Unit *u; assert(m); assert(cgroup); u = hashmap_get(m->cgroup_unit, cgroup); if (u) return u; p = strdupa_safe(cgroup); for (;;) { char *e; e = strrchr(p, '/'); if (!e || e == p) return hashmap_get(m->cgroup_unit, SPECIAL_ROOT_SLICE); *e = 0; u = hashmap_get(m->cgroup_unit, p); if (u) return u; } } Unit *manager_get_unit_by_pidref_cgroup(Manager *m, const PidRef *pid) { _cleanup_free_ char *cgroup = NULL; assert(m); if (cg_pidref_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup) < 0) return NULL; return manager_get_unit_by_cgroup(m, cgroup); } Unit *manager_get_unit_by_pidref_watching(Manager *m, const PidRef *pid) { Unit *u, **array; assert(m); if (!pidref_is_set(pid)) return NULL; u = hashmap_get(m->watch_pids, pid); if (u) return u; array = hashmap_get(m->watch_pids_more, pid); if (array) return array[0]; return NULL; } Unit *manager_get_unit_by_pidref(Manager *m, const PidRef *pid) { Unit *u; assert(m); /* Note that a process might be owned by multiple units, we return only one here, which is good * enough for most cases, though not strictly correct. We prefer the one reported by cgroup * membership, as that's the most relevant one as children of the process will be assigned to that * one, too, before all else. */ if (!pidref_is_set(pid)) return NULL; if (pidref_is_self(pid)) return hashmap_get(m->units, SPECIAL_INIT_SCOPE); if (pid->pid == 1) return NULL; u = manager_get_unit_by_pidref_cgroup(m, pid); if (u) return u; u = manager_get_unit_by_pidref_watching(m, pid); if (u) return u; return NULL; } Unit *manager_get_unit_by_pid(Manager *m, pid_t pid) { assert(m); if (!pid_is_valid(pid)) return NULL; return manager_get_unit_by_pidref(m, &PIDREF_MAKE_FROM_PID(pid)); } int manager_notify_cgroup_empty(Manager *m, const char *cgroup) { Unit *u; assert(m); assert(cgroup); /* Called on the legacy hierarchy whenever we get an explicit cgroup notification from the cgroup agent process * or from the --system instance */ log_debug("Got cgroup empty notification for: %s", cgroup); u = manager_get_unit_by_cgroup(m, cgroup); if (!u) return 0; unit_add_to_cgroup_empty_queue(u); return 1; } int unit_get_memory_available(Unit *u, uint64_t *ret) { uint64_t available = UINT64_MAX, current = 0; assert(u); assert(ret); /* If data from cgroups can be accessed, try to find out how much more memory a unit can * claim before hitting the configured cgroup limits (if any). Consider both MemoryHigh * and MemoryMax, and also any slice the unit might be nested below. */ do { uint64_t unit_available, unit_limit = UINT64_MAX; CGroupContext *unit_context; /* No point in continuing if we can't go any lower */ if (available == 0) break; unit_context = unit_get_cgroup_context(u); if (!unit_context) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) continue; (void) unit_get_memory_current(u, ¤t); /* in case of error, previous current propagates as lower bound */ if (unit_has_name(u, SPECIAL_ROOT_SLICE)) unit_limit = physical_memory(); else if (unit_context->memory_max == UINT64_MAX && unit_context->memory_high == UINT64_MAX) continue; unit_limit = MIN3(unit_limit, unit_context->memory_max, unit_context->memory_high); unit_available = LESS_BY(unit_limit, current); available = MIN(unit_available, available); } while ((u = UNIT_GET_SLICE(u))); *ret = available; return 0; } int unit_get_memory_current(Unit *u, uint64_t *ret) { int r; // FIXME: Merge this into unit_get_memory_accounting after support for cgroup v1 is dropped assert(u); assert(ret); if (!UNIT_CGROUP_BOOL(u, memory_accounting)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENODATA; /* The root cgroup doesn't expose this information, let's get it from /proc instead */ if (unit_has_host_root_cgroup(u)) return procfs_memory_get_used(ret); if ((crt->cgroup_realized_mask & CGROUP_MASK_MEMORY) == 0) return -ENODATA; r = cg_all_unified(); if (r < 0) return r; return cg_get_attribute_as_uint64("memory", crt->cgroup_path, r > 0 ? "memory.current" : "memory.usage_in_bytes", ret); } int unit_get_memory_accounting(Unit *u, CGroupMemoryAccountingMetric metric, uint64_t *ret) { static const char* const attributes_table[_CGROUP_MEMORY_ACCOUNTING_METRIC_MAX] = { [CGROUP_MEMORY_PEAK] = "memory.peak", [CGROUP_MEMORY_SWAP_CURRENT] = "memory.swap.current", [CGROUP_MEMORY_SWAP_PEAK] = "memory.swap.peak", [CGROUP_MEMORY_ZSWAP_CURRENT] = "memory.zswap.current", }; uint64_t bytes; bool updated = false; int r; assert(u); assert(metric >= 0); assert(metric < _CGROUP_MEMORY_ACCOUNTING_METRIC_MAX); if (!UNIT_CGROUP_BOOL(u, memory_accounting)) return -ENODATA; /* The root cgroup doesn't expose this information. */ if (unit_has_host_root_cgroup(u)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return -ENODATA; if (!crt->cgroup_path) /* If the cgroup is already gone, we try to find the last cached value. */ goto finish; if (!FLAGS_SET(crt->cgroup_realized_mask, CGROUP_MASK_MEMORY)) return -ENODATA; r = cg_all_unified(); if (r < 0) return r; if (r == 0) return -ENODATA; r = cg_get_attribute_as_uint64("memory", crt->cgroup_path, attributes_table[metric], &bytes); if (r < 0 && r != -ENODATA) return r; updated = r >= 0; finish: if (metric <= _CGROUP_MEMORY_ACCOUNTING_METRIC_CACHED_LAST) { uint64_t *last = &crt->memory_accounting_last[metric]; if (updated) *last = bytes; else if (*last != UINT64_MAX) bytes = *last; else return -ENODATA; } else if (!updated) return -ENODATA; if (ret) *ret = bytes; return 0; } int unit_get_tasks_current(Unit *u, uint64_t *ret) { assert(u); assert(ret); if (!UNIT_CGROUP_BOOL(u, tasks_accounting)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENODATA; /* The root cgroup doesn't expose this information, let's get it from /proc instead */ if (unit_has_host_root_cgroup(u)) return procfs_tasks_get_current(ret); if ((crt->cgroup_realized_mask & CGROUP_MASK_PIDS) == 0) return -ENODATA; return cg_get_attribute_as_uint64("pids", crt->cgroup_path, "pids.current", ret); } static int unit_get_cpu_usage_raw(const Unit *u, const CGroupRuntime *crt, nsec_t *ret) { int r; assert(u); assert(crt); assert(ret); if (!crt->cgroup_path) return -ENODATA; /* The root cgroup doesn't expose this information, let's get it from /proc instead */ if (unit_has_host_root_cgroup(u)) return procfs_cpu_get_usage(ret); /* Requisite controllers for CPU accounting are not enabled */ if ((get_cpu_accounting_mask() & ~crt->cgroup_realized_mask) != 0) return -ENODATA; r = cg_all_unified(); if (r < 0) return r; if (r == 0) return cg_get_attribute_as_uint64("cpuacct", crt->cgroup_path, "cpuacct.usage", ret); _cleanup_free_ char *val = NULL; uint64_t us; r = cg_get_keyed_attribute("cpu", crt->cgroup_path, "cpu.stat", STRV_MAKE("usage_usec"), &val); if (IN_SET(r, -ENOENT, -ENXIO)) return -ENODATA; if (r < 0) return r; r = safe_atou64(val, &us); if (r < 0) return r; *ret = us * NSEC_PER_USEC; return 0; } int unit_get_cpu_usage(Unit *u, nsec_t *ret) { nsec_t ns; int r; assert(u); /* Retrieve the current CPU usage counter. This will subtract the CPU counter taken when the unit was * started. If the cgroup has been removed already, returns the last cached value. To cache the value, simply * call this function with a NULL return value. */ if (!UNIT_CGROUP_BOOL(u, cpu_accounting)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return -ENODATA; r = unit_get_cpu_usage_raw(u, crt, &ns); if (r == -ENODATA && crt->cpu_usage_last != NSEC_INFINITY) { /* If we can't get the CPU usage anymore (because the cgroup was already removed, for example), use our * cached value. */ if (ret) *ret = crt->cpu_usage_last; return 0; } if (r < 0) return r; if (ns > crt->cpu_usage_base) ns -= crt->cpu_usage_base; else ns = 0; crt->cpu_usage_last = ns; if (ret) *ret = ns; return 0; } int unit_get_ip_accounting( Unit *u, CGroupIPAccountingMetric metric, uint64_t *ret) { uint64_t value; int fd, r; assert(u); assert(metric >= 0); assert(metric < _CGROUP_IP_ACCOUNTING_METRIC_MAX); assert(ret); if (!UNIT_CGROUP_BOOL(u, ip_accounting)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return -ENODATA; fd = IN_SET(metric, CGROUP_IP_INGRESS_BYTES, CGROUP_IP_INGRESS_PACKETS) ? crt->ip_accounting_ingress_map_fd : crt->ip_accounting_egress_map_fd; if (fd < 0) return -ENODATA; if (IN_SET(metric, CGROUP_IP_INGRESS_BYTES, CGROUP_IP_EGRESS_BYTES)) r = bpf_firewall_read_accounting(fd, &value, NULL); else r = bpf_firewall_read_accounting(fd, NULL, &value); if (r < 0) return r; /* Add in additional metrics from a previous runtime. Note that when reexecing/reloading the daemon we compile * all BPF programs and maps anew, but serialize the old counters. When deserializing we store them in the * ip_accounting_extra[] field, and add them in here transparently. */ *ret = value + crt->ip_accounting_extra[metric]; return r; } static uint64_t unit_get_effective_limit_one(Unit *u, CGroupLimitType type) { CGroupContext *cc; assert(u); assert(UNIT_HAS_CGROUP_CONTEXT(u)); if (unit_has_name(u, SPECIAL_ROOT_SLICE)) switch (type) { case CGROUP_LIMIT_MEMORY_MAX: case CGROUP_LIMIT_MEMORY_HIGH: return physical_memory(); case CGROUP_LIMIT_TASKS_MAX: return system_tasks_max(); default: assert_not_reached(); } cc = ASSERT_PTR(unit_get_cgroup_context(u)); switch (type) { /* Note: on legacy/hybrid hierarchies memory_max stays CGROUP_LIMIT_MAX unless configured * explicitly. Effective value of MemoryLimit= (cgroup v1) is not implemented. */ case CGROUP_LIMIT_MEMORY_MAX: return cc->memory_max; case CGROUP_LIMIT_MEMORY_HIGH: return cc->memory_high; case CGROUP_LIMIT_TASKS_MAX: return cgroup_tasks_max_resolve(&cc->tasks_max); default: assert_not_reached(); } } int unit_get_effective_limit(Unit *u, CGroupLimitType type, uint64_t *ret) { uint64_t infimum; assert(u); assert(ret); assert(type >= 0); assert(type < _CGROUP_LIMIT_TYPE_MAX); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return -EINVAL; infimum = unit_get_effective_limit_one(u, type); for (Unit *slice = UNIT_GET_SLICE(u); slice; slice = UNIT_GET_SLICE(slice)) infimum = MIN(infimum, unit_get_effective_limit_one(slice, type)); *ret = infimum; return 0; } static int unit_get_io_accounting_raw( const Unit *u, const CGroupRuntime *crt, uint64_t ret[static _CGROUP_IO_ACCOUNTING_METRIC_MAX]) { static const char* const field_names[_CGROUP_IO_ACCOUNTING_METRIC_MAX] = { [CGROUP_IO_READ_BYTES] = "rbytes=", [CGROUP_IO_WRITE_BYTES] = "wbytes=", [CGROUP_IO_READ_OPERATIONS] = "rios=", [CGROUP_IO_WRITE_OPERATIONS] = "wios=", }; uint64_t acc[_CGROUP_IO_ACCOUNTING_METRIC_MAX] = {}; _cleanup_free_ char *path = NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(u); assert(crt); if (!crt->cgroup_path) return -ENODATA; if (unit_has_host_root_cgroup(u)) return -ENODATA; /* TODO: return useful data for the top-level cgroup */ r = cg_all_unified(); if (r < 0) return r; if (r == 0) return -ENODATA; if (!FLAGS_SET(crt->cgroup_realized_mask, CGROUP_MASK_IO)) return -ENODATA; r = cg_get_path("io", crt->cgroup_path, "io.stat", &path); if (r < 0) return r; f = fopen(path, "re"); if (!f) return -errno; for (;;) { _cleanup_free_ char *line = NULL; const char *p; r = read_line(f, LONG_LINE_MAX, &line); if (r < 0) return r; if (r == 0) break; p = line; p += strcspn(p, WHITESPACE); /* Skip over device major/minor */ p += strspn(p, WHITESPACE); /* Skip over following whitespace */ for (;;) { _cleanup_free_ char *word = NULL; r = extract_first_word(&p, &word, NULL, EXTRACT_RETAIN_ESCAPE); if (r < 0) return r; if (r == 0) break; for (CGroupIOAccountingMetric i = 0; i < _CGROUP_IO_ACCOUNTING_METRIC_MAX; i++) { const char *x; x = startswith(word, field_names[i]); if (x) { uint64_t w; r = safe_atou64(x, &w); if (r < 0) return r; /* Sum up the stats of all devices */ acc[i] += w; break; } } } } memcpy(ret, acc, sizeof(acc)); return 0; } int unit_get_io_accounting( Unit *u, CGroupIOAccountingMetric metric, bool allow_cache, uint64_t *ret) { uint64_t raw[_CGROUP_IO_ACCOUNTING_METRIC_MAX]; int r; /* Retrieve an IO account parameter. This will subtract the counter when the unit was started. */ if (!UNIT_CGROUP_BOOL(u, io_accounting)) return -ENODATA; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return -ENODATA; if (allow_cache && crt->io_accounting_last[metric] != UINT64_MAX) goto done; r = unit_get_io_accounting_raw(u, crt, raw); if (r == -ENODATA && crt->io_accounting_last[metric] != UINT64_MAX) goto done; if (r < 0) return r; for (CGroupIOAccountingMetric i = 0; i < _CGROUP_IO_ACCOUNTING_METRIC_MAX; i++) { /* Saturated subtraction */ if (raw[i] > crt->io_accounting_base[i]) crt->io_accounting_last[i] = raw[i] - crt->io_accounting_base[i]; else crt->io_accounting_last[i] = 0; } done: if (ret) *ret = crt->io_accounting_last[metric]; return 0; } static int unit_reset_cpu_accounting(Unit *unit, CGroupRuntime *crt) { int r; assert(crt); crt->cpu_usage_base = 0; crt->cpu_usage_last = NSEC_INFINITY; if (unit) { r = unit_get_cpu_usage_raw(unit, crt, &crt->cpu_usage_base); if (r < 0 && r != -ENODATA) return r; } return 0; } static int unit_reset_io_accounting(Unit *unit, CGroupRuntime *crt) { int r; assert(crt); zero(crt->io_accounting_base); FOREACH_ELEMENT(i, crt->io_accounting_last) *i = UINT64_MAX; if (unit) { r = unit_get_io_accounting_raw(unit, crt, crt->io_accounting_base); if (r < 0 && r != -ENODATA) return r; } return 0; } static void cgroup_runtime_reset_memory_accounting_last(CGroupRuntime *crt) { assert(crt); FOREACH_ELEMENT(i, crt->memory_accounting_last) *i = UINT64_MAX; } static int cgroup_runtime_reset_ip_accounting(CGroupRuntime *crt) { int r = 0; assert(crt); if (crt->ip_accounting_ingress_map_fd >= 0) RET_GATHER(r, bpf_firewall_reset_accounting(crt->ip_accounting_ingress_map_fd)); if (crt->ip_accounting_egress_map_fd >= 0) RET_GATHER(r, bpf_firewall_reset_accounting(crt->ip_accounting_egress_map_fd)); zero(crt->ip_accounting_extra); return r; } int unit_reset_accounting(Unit *u) { int r = 0; assert(u); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return 0; cgroup_runtime_reset_memory_accounting_last(crt); RET_GATHER(r, unit_reset_cpu_accounting(u, crt)); RET_GATHER(r, unit_reset_io_accounting(u, crt)); RET_GATHER(r, cgroup_runtime_reset_ip_accounting(crt)); return r; } void unit_invalidate_cgroup(Unit *u, CGroupMask m) { assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return; if (m == 0) return; /* always invalidate compat pairs together */ if (m & (CGROUP_MASK_IO | CGROUP_MASK_BLKIO)) m |= CGROUP_MASK_IO | CGROUP_MASK_BLKIO; if (m & (CGROUP_MASK_CPU | CGROUP_MASK_CPUACCT)) m |= CGROUP_MASK_CPU | CGROUP_MASK_CPUACCT; if (FLAGS_SET(crt->cgroup_invalidated_mask, m)) /* NOP? */ return; crt->cgroup_invalidated_mask |= m; unit_add_to_cgroup_realize_queue(u); } void unit_invalidate_cgroup_bpf(Unit *u) { assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return; CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return; if (crt->cgroup_invalidated_mask & CGROUP_MASK_BPF_FIREWALL) /* NOP? */ return; crt->cgroup_invalidated_mask |= CGROUP_MASK_BPF_FIREWALL; unit_add_to_cgroup_realize_queue(u); /* If we are a slice unit, we also need to put compile a new BPF program for all our children, as the IP access * list of our children includes our own. */ if (u->type == UNIT_SLICE) { Unit *member; UNIT_FOREACH_DEPENDENCY(member, u, UNIT_ATOM_SLICE_OF) unit_invalidate_cgroup_bpf(member); } } void unit_cgroup_catchup(Unit *u) { assert(u); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return; /* We dropped the inotify watch during reexec/reload, so we need to * check these as they may have changed. * Note that (currently) the kernel doesn't actually update cgroup * file modification times, so we can't just serialize and then check * the mtime for file(s) we are interested in. */ (void) unit_check_cgroup_events(u); unit_add_to_cgroup_oom_queue(u); } bool unit_cgroup_delegate(Unit *u) { CGroupContext *c; assert(u); if (!UNIT_VTABLE(u)->can_delegate) return false; c = unit_get_cgroup_context(u); if (!c) return false; return c->delegate; } void manager_invalidate_startup_units(Manager *m) { Unit *u; assert(m); SET_FOREACH(u, m->startup_units) unit_invalidate_cgroup(u, CGROUP_MASK_CPU|CGROUP_MASK_IO|CGROUP_MASK_BLKIO|CGROUP_MASK_CPUSET); } static int unit_cgroup_freezer_kernel_state(Unit *u, FreezerState *ret) { _cleanup_free_ char *val = NULL; FreezerState s; int r; assert(u); assert(ret); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -EOWNERDEAD; r = cg_get_keyed_attribute( SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, "cgroup.events", STRV_MAKE("frozen"), &val); if (IN_SET(r, -ENOENT, -ENXIO)) return -ENODATA; if (r < 0) return r; if (streq(val, "0")) s = FREEZER_RUNNING; else if (streq(val, "1")) s = FREEZER_FROZEN; else { log_unit_debug(u, "Unexpected cgroup frozen state: %s", val); s = _FREEZER_STATE_INVALID; } *ret = s; return 0; } int unit_cgroup_freezer_action(Unit *u, FreezerAction action) { _cleanup_free_ char *path = NULL; FreezerState target, current, next; int r; assert(u); assert(IN_SET(action, FREEZER_FREEZE, FREEZER_PARENT_FREEZE, FREEZER_THAW, FREEZER_PARENT_THAW)); if (!cg_freezer_supported()) return 0; unit_next_freezer_state(u, action, &next, &target); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_realized) { /* No realized cgroup = nothing to freeze */ u->freezer_state = freezer_state_finish(next); return 0; } r = unit_cgroup_freezer_kernel_state(u, ¤t); if (r < 0) return r; if (current == target) next = freezer_state_finish(next); else if (IN_SET(next, FREEZER_FROZEN, FREEZER_FROZEN_BY_PARENT, FREEZER_RUNNING)) { /* We're transitioning into a finished state, which implies that the cgroup's * current state already matches the target and thus we'd return 0. But, reality * shows otherwise. This indicates that our freezer_state tracking has diverged * from the real state of the cgroup, which can happen if someone meddles with the * cgroup from underneath us. This really shouldn't happen during normal operation, * though. So, let's warn about it and fix up the state to be valid */ log_unit_warning(u, "Unit wants to transition to %s freezer state but cgroup is unexpectedly %s, fixing up.", freezer_state_to_string(next), freezer_state_to_string(current) ?: "(invalid)"); if (next == FREEZER_FROZEN) next = FREEZER_FREEZING; else if (next == FREEZER_FROZEN_BY_PARENT) next = FREEZER_FREEZING_BY_PARENT; else if (next == FREEZER_RUNNING) next = FREEZER_THAWING; } r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, crt->cgroup_path, "cgroup.freeze", &path); if (r < 0) return r; log_unit_debug(u, "Unit freezer state was %s, now %s.", freezer_state_to_string(u->freezer_state), freezer_state_to_string(next)); r = write_string_file(path, one_zero(target == FREEZER_FROZEN), WRITE_STRING_FILE_DISABLE_BUFFER); if (r < 0) return r; u->freezer_state = next; return target != current; } int unit_get_cpuset(Unit *u, CPUSet *cpus, const char *name) { _cleanup_free_ char *v = NULL; int r; assert(u); assert(cpus); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt || !crt->cgroup_path) return -ENODATA; if ((crt->cgroup_realized_mask & CGROUP_MASK_CPUSET) == 0) return -ENODATA; r = cg_all_unified(); if (r < 0) return r; if (r == 0) return -ENODATA; r = cg_get_attribute("cpuset", crt->cgroup_path, name, &v); if (r == -ENOENT) return -ENODATA; if (r < 0) return r; return parse_cpu_set_full(v, cpus, false, NULL, NULL, 0, NULL); } CGroupRuntime* cgroup_runtime_new(void) { _cleanup_(cgroup_runtime_freep) CGroupRuntime *crt = NULL; crt = new(CGroupRuntime, 1); if (!crt) return NULL; *crt = (CGroupRuntime) { .cgroup_control_inotify_wd = -1, .cgroup_memory_inotify_wd = -1, .ip_accounting_ingress_map_fd = -EBADF, .ip_accounting_egress_map_fd = -EBADF, .ipv4_allow_map_fd = -EBADF, .ipv6_allow_map_fd = -EBADF, .ipv4_deny_map_fd = -EBADF, .ipv6_deny_map_fd = -EBADF, .cgroup_invalidated_mask = _CGROUP_MASK_ALL, }; unit_reset_cpu_accounting(/* unit = */ NULL, crt); unit_reset_io_accounting(/* unit = */ NULL, crt); cgroup_runtime_reset_memory_accounting_last(crt); assert_se(cgroup_runtime_reset_ip_accounting(crt) >= 0); return TAKE_PTR(crt); } CGroupRuntime* cgroup_runtime_free(CGroupRuntime *crt) { if (!crt) return NULL; fdset_free(crt->initial_socket_bind_link_fds); #if BPF_FRAMEWORK bpf_link_free(crt->ipv4_socket_bind_link); bpf_link_free(crt->ipv6_socket_bind_link); #endif hashmap_free(crt->bpf_foreign_by_key); bpf_program_free(crt->bpf_device_control_installed); #if BPF_FRAMEWORK bpf_link_free(crt->restrict_ifaces_ingress_bpf_link); bpf_link_free(crt->restrict_ifaces_egress_bpf_link); #endif fdset_free(crt->initial_restrict_ifaces_link_fds); safe_close(crt->ipv4_allow_map_fd); safe_close(crt->ipv6_allow_map_fd); safe_close(crt->ipv4_deny_map_fd); safe_close(crt->ipv6_deny_map_fd); bpf_program_free(crt->ip_bpf_ingress); bpf_program_free(crt->ip_bpf_ingress_installed); bpf_program_free(crt->ip_bpf_egress); bpf_program_free(crt->ip_bpf_egress_installed); set_free(crt->ip_bpf_custom_ingress); set_free(crt->ip_bpf_custom_ingress_installed); set_free(crt->ip_bpf_custom_egress); set_free(crt->ip_bpf_custom_egress_installed); free(crt->cgroup_path); return mfree(crt); } static const char* const ip_accounting_metric_field_table[_CGROUP_IP_ACCOUNTING_METRIC_MAX] = { [CGROUP_IP_INGRESS_BYTES] = "ip-accounting-ingress-bytes", [CGROUP_IP_INGRESS_PACKETS] = "ip-accounting-ingress-packets", [CGROUP_IP_EGRESS_BYTES] = "ip-accounting-egress-bytes", [CGROUP_IP_EGRESS_PACKETS] = "ip-accounting-egress-packets", }; DEFINE_PRIVATE_STRING_TABLE_LOOKUP(ip_accounting_metric_field, CGroupIPAccountingMetric); static const char* const io_accounting_metric_field_base_table[_CGROUP_IO_ACCOUNTING_METRIC_MAX] = { [CGROUP_IO_READ_BYTES] = "io-accounting-read-bytes-base", [CGROUP_IO_WRITE_BYTES] = "io-accounting-write-bytes-base", [CGROUP_IO_READ_OPERATIONS] = "io-accounting-read-operations-base", [CGROUP_IO_WRITE_OPERATIONS] = "io-accounting-write-operations-base", }; DEFINE_PRIVATE_STRING_TABLE_LOOKUP(io_accounting_metric_field_base, CGroupIOAccountingMetric); static const char* const io_accounting_metric_field_last_table[_CGROUP_IO_ACCOUNTING_METRIC_MAX] = { [CGROUP_IO_READ_BYTES] = "io-accounting-read-bytes-last", [CGROUP_IO_WRITE_BYTES] = "io-accounting-write-bytes-last", [CGROUP_IO_READ_OPERATIONS] = "io-accounting-read-operations-last", [CGROUP_IO_WRITE_OPERATIONS] = "io-accounting-write-operations-last", }; DEFINE_PRIVATE_STRING_TABLE_LOOKUP(io_accounting_metric_field_last, CGroupIOAccountingMetric); static const char* const memory_accounting_metric_field_last_table[_CGROUP_MEMORY_ACCOUNTING_METRIC_CACHED_LAST + 1] = { [CGROUP_MEMORY_PEAK] = "memory-accounting-peak", [CGROUP_MEMORY_SWAP_PEAK] = "memory-accounting-swap-peak", }; DEFINE_PRIVATE_STRING_TABLE_LOOKUP(memory_accounting_metric_field_last, CGroupMemoryAccountingMetric); static int serialize_cgroup_mask(FILE *f, const char *key, CGroupMask mask) { _cleanup_free_ char *s = NULL; int r; assert(f); assert(key); if (mask == 0) return 0; r = cg_mask_to_string(mask, &s); if (r < 0) return log_error_errno(r, "Failed to format cgroup mask: %m"); return serialize_item(f, key, s); } int cgroup_runtime_serialize(Unit *u, FILE *f, FDSet *fds) { int r; assert(u); assert(f); assert(fds); CGroupRuntime *crt = unit_get_cgroup_runtime(u); if (!crt) return 0; (void) serialize_item_format(f, "cpu-usage-base", "%" PRIu64, crt->cpu_usage_base); if (crt->cpu_usage_last != NSEC_INFINITY) (void) serialize_item_format(f, "cpu-usage-last", "%" PRIu64, crt->cpu_usage_last); if (crt->managed_oom_kill_last > 0) (void) serialize_item_format(f, "managed-oom-kill-last", "%" PRIu64, crt->managed_oom_kill_last); if (crt->oom_kill_last > 0) (void) serialize_item_format(f, "oom-kill-last", "%" PRIu64, crt->oom_kill_last); for (CGroupMemoryAccountingMetric metric = 0; metric <= _CGROUP_MEMORY_ACCOUNTING_METRIC_CACHED_LAST; metric++) { uint64_t v; r = unit_get_memory_accounting(u, metric, &v); if (r >= 0) (void) serialize_item_format(f, memory_accounting_metric_field_last_to_string(metric), "%" PRIu64, v); } for (CGroupIPAccountingMetric m = 0; m < _CGROUP_IP_ACCOUNTING_METRIC_MAX; m++) { uint64_t v; r = unit_get_ip_accounting(u, m, &v); if (r >= 0) (void) serialize_item_format(f, ip_accounting_metric_field_to_string(m), "%" PRIu64, v); } for (CGroupIOAccountingMetric im = 0; im < _CGROUP_IO_ACCOUNTING_METRIC_MAX; im++) { (void) serialize_item_format(f, io_accounting_metric_field_base_to_string(im), "%" PRIu64, crt->io_accounting_base[im]); if (crt->io_accounting_last[im] != UINT64_MAX) (void) serialize_item_format(f, io_accounting_metric_field_last_to_string(im), "%" PRIu64, crt->io_accounting_last[im]); } if (crt->cgroup_path) (void) serialize_item(f, "cgroup", crt->cgroup_path); if (crt->cgroup_id != 0) (void) serialize_item_format(f, "cgroup-id", "%" PRIu64, crt->cgroup_id); (void) serialize_bool(f, "cgroup-realized", crt->cgroup_realized); (void) serialize_cgroup_mask(f, "cgroup-realized-mask", crt->cgroup_realized_mask); (void) serialize_cgroup_mask(f, "cgroup-enabled-mask", crt->cgroup_enabled_mask); (void) serialize_cgroup_mask(f, "cgroup-invalidated-mask", crt->cgroup_invalidated_mask); (void) bpf_socket_bind_serialize(u, f, fds); (void) bpf_program_serialize_attachment(f, fds, "ip-bpf-ingress-installed", crt->ip_bpf_ingress_installed); (void) bpf_program_serialize_attachment(f, fds, "ip-bpf-egress-installed", crt->ip_bpf_egress_installed); (void) bpf_program_serialize_attachment(f, fds, "bpf-device-control-installed", crt->bpf_device_control_installed); (void) bpf_program_serialize_attachment_set(f, fds, "ip-bpf-custom-ingress-installed", crt->ip_bpf_custom_ingress_installed); (void) bpf_program_serialize_attachment_set(f, fds, "ip-bpf-custom-egress-installed", crt->ip_bpf_custom_egress_installed); (void) bpf_restrict_ifaces_serialize(u, f, fds); return 0; } #define MATCH_DESERIALIZE(u, key, l, v, parse_func, target) \ ({ \ bool _deserialize_matched = streq(l, key); \ if (_deserialize_matched) { \ CGroupRuntime *crt = unit_setup_cgroup_runtime(u); \ if (!crt) \ log_oom_debug(); \ else { \ int _deserialize_r = parse_func(v); \ if (_deserialize_r < 0) \ log_unit_debug_errno(u, _deserialize_r, \ "Failed to parse \"%s=%s\", ignoring.", l, v); \ else \ crt->target = _deserialize_r; \ } \ } \ _deserialize_matched; \ }) #define MATCH_DESERIALIZE_IMMEDIATE(u, key, l, v, parse_func, target) \ ({ \ bool _deserialize_matched = streq(l, key); \ if (_deserialize_matched) { \ CGroupRuntime *crt = unit_setup_cgroup_runtime(u); \ if (!crt) \ log_oom_debug(); \ else { \ int _deserialize_r = parse_func(v, &crt->target); \ if (_deserialize_r < 0) \ log_unit_debug_errno(u, _deserialize_r, \ "Failed to parse \"%s=%s\", ignoring", l, v); \ } \ } \ _deserialize_matched; \ }) #define MATCH_DESERIALIZE_METRIC(u, key, l, v, parse_func, target) \ ({ \ bool _deserialize_matched = streq(l, key); \ if (_deserialize_matched) { \ CGroupRuntime *crt = unit_setup_cgroup_runtime(u); \ if (!crt) \ log_oom_debug(); \ else { \ int _deserialize_r = parse_func(v); \ if (_deserialize_r < 0) \ log_unit_debug_errno(u, _deserialize_r, \ "Failed to parse \"%s=%s\", ignoring.", l, v); \ else \ crt->target = _deserialize_r; \ } \ } \ _deserialize_matched; \ }) int cgroup_runtime_deserialize_one(Unit *u, const char *key, const char *value, FDSet *fds) { int r; assert(u); assert(value); if (!UNIT_HAS_CGROUP_CONTEXT(u)) return 0; if (MATCH_DESERIALIZE_IMMEDIATE(u, "cpu-usage-base", key, value, safe_atou64, cpu_usage_base) || MATCH_DESERIALIZE_IMMEDIATE(u, "cpuacct-usage-base", key, value, safe_atou64, cpu_usage_base)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "cpu-usage-last", key, value, safe_atou64, cpu_usage_last)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "managed-oom-kill-last", key, value, safe_atou64, managed_oom_kill_last)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "oom-kill-last", key, value, safe_atou64, oom_kill_last)) return 1; if (streq(key, "cgroup")) { r = unit_set_cgroup_path(u, value); if (r < 0) log_unit_debug_errno(u, r, "Failed to set cgroup path %s, ignoring: %m", value); (void) unit_watch_cgroup(u); (void) unit_watch_cgroup_memory(u); return 1; } if (MATCH_DESERIALIZE_IMMEDIATE(u, "cgroup-id", key, value, safe_atou64, cgroup_id)) return 1; if (MATCH_DESERIALIZE(u, "cgroup-realized", key, value, parse_boolean, cgroup_realized)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "cgroup-realized-mask", key, value, cg_mask_from_string, cgroup_realized_mask)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "cgroup-enabled-mask", key, value, cg_mask_from_string, cgroup_enabled_mask)) return 1; if (MATCH_DESERIALIZE_IMMEDIATE(u, "cgroup-invalidated-mask", key, value, cg_mask_from_string, cgroup_invalidated_mask)) return 1; if (STR_IN_SET(key, "ipv4-socket-bind-bpf-link-fd", "ipv6-socket-bind-bpf-link-fd")) { int fd; fd = deserialize_fd(fds, value); if (fd >= 0) (void) bpf_socket_bind_add_initial_link_fd(u, fd); return 1; } if (STR_IN_SET(key, "ip-bpf-ingress-installed", "ip-bpf-egress-installed", "bpf-device-control-installed", "ip-bpf-custom-ingress-installed", "ip-bpf-custom-egress-installed")) { CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) log_oom_debug(); else { if (streq(key, "ip-bpf-ingress-installed")) (void) bpf_program_deserialize_attachment(value, fds, &crt->ip_bpf_ingress_installed); if (streq(key, "ip-bpf-egress-installed")) (void) bpf_program_deserialize_attachment(value, fds, &crt->ip_bpf_egress_installed); if (streq(key, "bpf-device-control-installed")) (void) bpf_program_deserialize_attachment(value, fds, &crt->bpf_device_control_installed); if (streq(key, "ip-bpf-custom-ingress-installed")) (void) bpf_program_deserialize_attachment_set(value, fds, &crt->ip_bpf_custom_ingress_installed); if (streq(key, "ip-bpf-custom-egress-installed")) (void) bpf_program_deserialize_attachment_set(value, fds, &crt->ip_bpf_custom_egress_installed); } return 1; } if (streq(key, "restrict-ifaces-bpf-fd")) { int fd; fd = deserialize_fd(fds, value); if (fd >= 0) (void) bpf_restrict_ifaces_add_initial_link_fd(u, fd); return 1; } CGroupMemoryAccountingMetric mm = memory_accounting_metric_field_last_from_string(key); if (mm >= 0) { uint64_t c; r = safe_atou64(value, &c); if (r < 0) log_unit_debug(u, "Failed to parse memory accounting last value %s, ignoring.", value); else { CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) log_oom_debug(); else crt->memory_accounting_last[mm] = c; } return 1; } CGroupIPAccountingMetric ipm = ip_accounting_metric_field_from_string(key); if (ipm >= 0) { uint64_t c; r = safe_atou64(value, &c); if (r < 0) log_unit_debug(u, "Failed to parse IP accounting value %s, ignoring.", value); else { CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) log_oom_debug(); else crt->ip_accounting_extra[ipm] = c; } return 1; } CGroupIOAccountingMetric iom = io_accounting_metric_field_base_from_string(key); if (iom >= 0) { uint64_t c; r = safe_atou64(value, &c); if (r < 0) log_unit_debug(u, "Failed to parse IO accounting base value %s, ignoring.", value); else { CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) log_oom_debug(); else crt->io_accounting_base[iom] = c; } return 1; } iom = io_accounting_metric_field_last_from_string(key); if (iom >= 0) { uint64_t c; r = safe_atou64(value, &c); if (r < 0) log_unit_debug(u, "Failed to parse IO accounting last value %s, ignoring.", value); else { CGroupRuntime *crt = unit_setup_cgroup_runtime(u); if (!crt) log_oom_debug(); else crt->io_accounting_last[iom] = c; } return 1; } return 0; } static const char* const cgroup_device_policy_table[_CGROUP_DEVICE_POLICY_MAX] = { [CGROUP_DEVICE_POLICY_AUTO] = "auto", [CGROUP_DEVICE_POLICY_CLOSED] = "closed", [CGROUP_DEVICE_POLICY_STRICT] = "strict", }; DEFINE_STRING_TABLE_LOOKUP(cgroup_device_policy, CGroupDevicePolicy); static const char* const cgroup_pressure_watch_table[_CGROUP_PRESSURE_WATCH_MAX] = { [CGROUP_PRESSURE_WATCH_OFF] = "off", [CGROUP_PRESSURE_WATCH_AUTO] = "auto", [CGROUP_PRESSURE_WATCH_ON] = "on", [CGROUP_PRESSURE_WATCH_SKIP] = "skip", }; DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(cgroup_pressure_watch, CGroupPressureWatch, CGROUP_PRESSURE_WATCH_ON); static const char* const cgroup_ip_accounting_metric_table[_CGROUP_IP_ACCOUNTING_METRIC_MAX] = { [CGROUP_IP_INGRESS_BYTES] = "IPIngressBytes", [CGROUP_IP_EGRESS_BYTES] = "IPEgressBytes", [CGROUP_IP_INGRESS_PACKETS] = "IPIngressPackets", [CGROUP_IP_EGRESS_PACKETS] = "IPEgressPackets", }; DEFINE_STRING_TABLE_LOOKUP(cgroup_ip_accounting_metric, CGroupIPAccountingMetric); static const char* const cgroup_io_accounting_metric_table[_CGROUP_IO_ACCOUNTING_METRIC_MAX] = { [CGROUP_IO_READ_BYTES] = "IOReadBytes", [CGROUP_IO_WRITE_BYTES] = "IOWriteBytes", [CGROUP_IO_READ_OPERATIONS] = "IOReadOperations", [CGROUP_IO_WRITE_OPERATIONS] = "IOWriteOperations", }; DEFINE_STRING_TABLE_LOOKUP(cgroup_io_accounting_metric, CGroupIOAccountingMetric); static const char* const cgroup_memory_accounting_metric_table[_CGROUP_MEMORY_ACCOUNTING_METRIC_MAX] = { [CGROUP_MEMORY_PEAK] = "MemoryPeak", [CGROUP_MEMORY_SWAP_CURRENT] = "MemorySwapCurrent", [CGROUP_MEMORY_SWAP_PEAK] = "MemorySwapPeak", [CGROUP_MEMORY_ZSWAP_CURRENT] = "MemoryZSwapCurrent", }; DEFINE_STRING_TABLE_LOOKUP(cgroup_memory_accounting_metric, CGroupMemoryAccountingMetric); static const char *const cgroup_effective_limit_type_table[_CGROUP_LIMIT_TYPE_MAX] = { [CGROUP_LIMIT_MEMORY_MAX] = "EffectiveMemoryMax", [CGROUP_LIMIT_MEMORY_HIGH] = "EffectiveMemoryHigh", [CGROUP_LIMIT_TASKS_MAX] = "EffectiveTasksMax", }; DEFINE_STRING_TABLE_LOOKUP(cgroup_effective_limit_type, CGroupLimitType);