Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 428 insertions, 0 deletions

diff --git a/src/basic/rlimit-util.c b/src/basic/rlimit-util.c
new file mode 100644
index 0000000..c1f0b2b
--- /dev/null
+++ b/src/basic/rlimit-util.c
@@ -0,0 +1,428 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+
+#include "alloc-util.h"
+#include "errno-util.h"
+#include "extract-word.h"
+#include "fd-util.h"
+#include "format-util.h"
+#include "macro.h"
+#include "missing_resource.h"
+#include "rlimit-util.h"
+#include "string-table.h"
+#include "time-util.h"
+
+int setrlimit_closest(int resource, const struct rlimit *rlim) {
+        struct rlimit highest, fixed;
+
+        assert(rlim);
+
+        if (setrlimit(resource, rlim) >= 0)
+                return 0;
+
+        if (errno != EPERM)
+                return -errno;
+
+        /* So we failed to set the desired setrlimit, then let's try
+         * to get as close as we can */
+        if (getrlimit(resource, &highest) < 0)
+                return -errno;
+
+        /* If the hard limit is unbounded anyway, then the EPERM had other reasons, let's propagate the original EPERM
+         * then */
+        if (highest.rlim_max == RLIM_INFINITY)
+                return -EPERM;
+
+        fixed = (struct rlimit) {
+                .rlim_cur = MIN(rlim->rlim_cur, highest.rlim_max),
+                .rlim_max = MIN(rlim->rlim_max, highest.rlim_max),
+        };
+
+        /* Shortcut things if we wouldn't change anything. */
+        if (fixed.rlim_cur == highest.rlim_cur &&
+            fixed.rlim_max == highest.rlim_max)
+                return 0;
+
+        log_debug("Failed at setting rlimit " RLIM_FMT " for resource RLIMIT_%s. Will attempt setting value " RLIM_FMT " instead.", rlim->rlim_max, rlimit_to_string(resource), fixed.rlim_max);
+
+        return RET_NERRNO(setrlimit(resource, &fixed));
+}
+
+int setrlimit_closest_all(const struct rlimit *const *rlim, int *which_failed) {
+        int r;
+
+        assert(rlim);
+
+        /* On failure returns the limit's index that failed in *which_failed, but only if non-NULL */
+
+        for (int i = 0; i < _RLIMIT_MAX; i++) {
+                if (!rlim[i])
+                        continue;
+
+                r = setrlimit_closest(i, rlim[i]);
+                if (r < 0) {
+                        if (which_failed)
+                                *which_failed = i;
+
+                        return r;
+                }
+        }
+
+        if (which_failed)
+                *which_failed = -1;
+
+        return 0;
+}
+
+static int rlimit_parse_u64(const char *val, rlim_t *ret) {
+        uint64_t u;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        /* setrlimit(2) suggests rlim_t is always 64-bit on Linux. */
+        assert_cc(sizeof(rlim_t) == sizeof(uint64_t));
+
+        r = safe_atou64(val, &u);
+        if (r < 0)
+                return r;
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_size(const char *val, rlim_t *ret) {
+        uint64_t u;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_size(val, 1024, &u);
+        if (r < 0)
+                return r;
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_sec(const char *val, rlim_t *ret) {
+        uint64_t u;
+        usec_t t;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_sec(val, &t);
+        if (r < 0)
+                return r;
+        if (t == USEC_INFINITY) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        u = (uint64_t) DIV_ROUND_UP(t, USEC_PER_SEC);
+        if (u >= (uint64_t) RLIM_INFINITY)
+                return -ERANGE;
+
+        *ret = (rlim_t) u;
+        return 0;
+}
+
+static int rlimit_parse_usec(const char *val, rlim_t *ret) {
+        usec_t t;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        if (streq(val, "infinity")) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        r = parse_time(val, &t, 1);
+        if (r < 0)
+                return r;
+        if (t == USEC_INFINITY) {
+                *ret = RLIM_INFINITY;
+                return 0;
+        }
+
+        *ret = (rlim_t) t;
+        return 0;
+}
+
+static int rlimit_parse_nice(const char *val, rlim_t *ret) {
+        uint64_t rl;
+        int r;
+
+        /* So, Linux is weird. The range for RLIMIT_NICE is 40..1, mapping to the nice levels -20..19. However, the
+         * RLIMIT_NICE limit defaults to 0 by the kernel, i.e. a value that maps to nice level 20, which of course is
+         * bogus and does not exist. In order to permit parsing the RLIMIT_NICE of 0 here we hence implement a slight
+         * asymmetry: when parsing as positive nice level we permit 0..19. When parsing as negative nice level, we
+         * permit -20..0. But when parsing as raw resource limit value then we also allow the special value 0.
+         *
+         * Yeah, Linux is quality engineering sometimes... */
+
+        if (val[0] == '+') {
+
+                /* Prefixed with "+": Parse as positive user-friendly nice value */
+                r = safe_atou64(val + 1, &rl);
+                if (r < 0)
+                        return r;
+
+                if (rl >= PRIO_MAX)
+                        return -ERANGE;
+
+                rl = 20 - rl;
+
+        } else if (val[0] == '-') {
+
+                /* Prefixed with "-": Parse as negative user-friendly nice value */
+                r = safe_atou64(val + 1, &rl);
+                if (r < 0)
+                        return r;
+
+                if (rl > (uint64_t) (-PRIO_MIN))
+                        return -ERANGE;
+
+                rl = 20 + rl;
+        } else {
+
+                /* Not prefixed: parse as raw resource limit value */
+                r = safe_atou64(val, &rl);
+                if (r < 0)
+                        return r;
+
+                if (rl > (uint64_t) (20 - PRIO_MIN))
+                        return -ERANGE;
+        }
+
+        *ret = (rlim_t) rl;
+        return 0;
+}
+
+static int (*const rlimit_parse_table[_RLIMIT_MAX])(const char *val, rlim_t *ret) = {
+        [RLIMIT_CPU] = rlimit_parse_sec,
+        [RLIMIT_FSIZE] = rlimit_parse_size,
+        [RLIMIT_DATA] = rlimit_parse_size,
+        [RLIMIT_STACK] = rlimit_parse_size,
+        [RLIMIT_CORE] = rlimit_parse_size,
+        [RLIMIT_RSS] = rlimit_parse_size,
+        [RLIMIT_NOFILE] = rlimit_parse_u64,
+        [RLIMIT_AS] = rlimit_parse_size,
+        [RLIMIT_NPROC] = rlimit_parse_u64,
+        [RLIMIT_MEMLOCK] = rlimit_parse_size,
+        [RLIMIT_LOCKS] = rlimit_parse_u64,
+        [RLIMIT_SIGPENDING] = rlimit_parse_u64,
+        [RLIMIT_MSGQUEUE] = rlimit_parse_size,
+        [RLIMIT_NICE] = rlimit_parse_nice,
+        [RLIMIT_RTPRIO] = rlimit_parse_u64,
+        [RLIMIT_RTTIME] = rlimit_parse_usec,
+};
+
+int rlimit_parse_one(int resource, const char *val, rlim_t *ret) {
+        assert(val);
+        assert(ret);
+
+        if (resource < 0)
+                return -EINVAL;
+        if (resource >= _RLIMIT_MAX)
+                return -EINVAL;
+
+        return rlimit_parse_table[resource](val, ret);
+}
+
+int rlimit_parse(int resource, const char *val, struct rlimit *ret) {
+        _cleanup_free_ char *hard = NULL, *soft = NULL;
+        rlim_t hl, sl;
+        int r;
+
+        assert(val);
+        assert(ret);
+
+        r = extract_first_word(&val, &soft, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
+        r = rlimit_parse_one(resource, soft, &sl);
+        if (r < 0)
+                return r;
+
+        r = extract_first_word(&val, &hard, ":", EXTRACT_DONT_COALESCE_SEPARATORS);
+        if (r < 0)
+                return r;
+        if (!isempty(val))
+                return -EINVAL;
+        if (r == 0)
+                hl = sl;
+        else {
+                r = rlimit_parse_one(resource, hard, &hl);
+                if (r < 0)
+                        return r;
+                if (sl > hl)
+                        return -EILSEQ;
+        }
+
+        *ret = (struct rlimit) {
+                .rlim_cur = sl,
+                .rlim_max = hl,
+        };
+
+        return 0;
+}
+
+int rlimit_format(const struct rlimit *rl, char **ret) {
+        _cleanup_free_ char *s = NULL;
+        int r;
+
+        assert(rl);
+        assert(ret);
+
+        if (rl->rlim_cur >= RLIM_INFINITY && rl->rlim_max >= RLIM_INFINITY)
+                r = free_and_strdup(&s, "infinity");
+        else if (rl->rlim_cur >= RLIM_INFINITY)
+                r = asprintf(&s, "infinity:" RLIM_FMT, rl->rlim_max);
+        else if (rl->rlim_max >= RLIM_INFINITY)
+                r = asprintf(&s, RLIM_FMT ":infinity", rl->rlim_cur);
+        else if (rl->rlim_cur == rl->rlim_max)
+                r = asprintf(&s, RLIM_FMT, rl->rlim_cur);
+        else
+                r = asprintf(&s, RLIM_FMT ":" RLIM_FMT, rl->rlim_cur, rl->rlim_max);
+        if (r < 0)
+                return -ENOMEM;
+
+        *ret = TAKE_PTR(s);
+        return 0;
+}
+
+static const char* const rlimit_table[_RLIMIT_MAX] = {
+        [RLIMIT_AS]         = "AS",
+        [RLIMIT_CORE]       = "CORE",
+        [RLIMIT_CPU]        = "CPU",
+        [RLIMIT_DATA]       = "DATA",
+        [RLIMIT_FSIZE]      = "FSIZE",
+        [RLIMIT_LOCKS]      = "LOCKS",
+        [RLIMIT_MEMLOCK]    = "MEMLOCK",
+        [RLIMIT_MSGQUEUE]   = "MSGQUEUE",
+        [RLIMIT_NICE]       = "NICE",
+        [RLIMIT_NOFILE]     = "NOFILE",
+        [RLIMIT_NPROC]      = "NPROC",
+        [RLIMIT_RSS]        = "RSS",
+        [RLIMIT_RTPRIO]     = "RTPRIO",
+        [RLIMIT_RTTIME]     = "RTTIME",
+        [RLIMIT_SIGPENDING] = "SIGPENDING",
+        [RLIMIT_STACK]      = "STACK",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(rlimit, int);
+
+int rlimit_from_string_harder(const char *s) {
+        const char *suffix;
+
+        /* The official prefix */
+        suffix = startswith(s, "RLIMIT_");
+        if (suffix)
+                return rlimit_from_string(suffix);
+
+        /* Our own unit file setting prefix */
+        suffix = startswith(s, "Limit");
+        if (suffix)
+                return rlimit_from_string(suffix);
+
+        return rlimit_from_string(s);
+}
+
+void rlimit_free_all(struct rlimit **rl) {
+        free_many((void**) rl, _RLIMIT_MAX);
+}
+
+int rlimit_copy_all(struct rlimit* target[static _RLIMIT_MAX], struct rlimit* const source[static _RLIMIT_MAX]) {
+        struct rlimit* copy[_RLIMIT_MAX] = {};
+
+        assert(target);
+        assert(source);
+
+        for (int i = 0; i < _RLIMIT_MAX; i++) {
+                if (!source[i])
+                        continue;
+
+                copy[i] = newdup(struct rlimit, source[i], 1);
+                if (!copy[i]) {
+                        rlimit_free_all(copy);
+                        return -ENOMEM;
+                }
+        }
+
+        memcpy(target, copy, sizeof(struct rlimit*) * _RLIMIT_MAX);
+        return 0;
+}
+
+int rlimit_nofile_bump(int limit) {
+        int r;
+
+        /* Bumps the (soft) RLIMIT_NOFILE resource limit as close as possible to the specified limit. If a negative
+         * limit is specified, bumps it to the maximum the kernel and the hard resource limit allows. This call should
+         * be used by all our programs that might need a lot of fds, and that know how to deal with high fd numbers
+         * (i.e. do not use select() — which chokes on fds >= 1024) */
+
+        if (limit < 0)
+                limit = read_nr_open();
+
+        if (limit < 3)
+                limit = 3;
+
+        r = setrlimit_closest(RLIMIT_NOFILE, &RLIMIT_MAKE_CONST(limit));
+        if (r < 0)
+                return log_debug_errno(r, "Failed to set RLIMIT_NOFILE: %m");
+
+        return 0;
+}
+
+int rlimit_nofile_safe(void) {
+        struct rlimit rl;
+
+        /* Resets RLIMIT_NOFILE's soft limit FD_SETSIZE (i.e. 1024), for compatibility with software still using
+         * select() */
+
+        if (getrlimit(RLIMIT_NOFILE, &rl) < 0)
+                return log_debug_errno(errno, "Failed to query RLIMIT_NOFILE: %m");
+
+        if (rl.rlim_cur <= FD_SETSIZE)
+                return 0;
+
+        /* So we might have inherited a hard limit that's larger than the kernel's maximum limit as stored in
+         * /proc/sys/fs/nr_open. If we pass this hard limit unmodified to setrlimit(), we'll get EPERM. To
+         * make sure that doesn't happen, let's limit our hard limit to the value from nr_open. */
+        rl.rlim_max = MIN(rl.rlim_max, (rlim_t) read_nr_open());
+        rl.rlim_cur = MIN((rlim_t) FD_SETSIZE, rl.rlim_max);
+        if (setrlimit(RLIMIT_NOFILE, &rl) < 0)
+                return log_debug_errno(errno, "Failed to lower RLIMIT_NOFILE's soft limit to " RLIM_FMT ": %m", rl.rlim_cur);
+
+        return 1;
+}