diff options
Diffstat (limited to 'src/coredump')
| -rw-r--r-- | src/coredump/coredump-vacuum.c | 245 | ||||
| -rw-r--r-- | src/coredump/coredump-vacuum.h | 7 | ||||
| -rw-r--r-- | src/coredump/coredump.c | 1405 | ||||
| -rw-r--r-- | src/coredump/coredump.conf | 21 | ||||
| -rw-r--r-- | src/coredump/coredumpctl.c | 1096 | ||||
| -rw-r--r-- | src/coredump/meson.build | 28 | ||||
| -rw-r--r-- | src/coredump/stacktrace.c | 185 | ||||
| -rw-r--r-- | src/coredump/stacktrace.h | 4 | ||||
| -rw-r--r-- | src/coredump/test-coredump-vacuum.c | 13 |
9 files changed, 3004 insertions, 0 deletions
diff --git a/src/coredump/coredump-vacuum.c b/src/coredump/coredump-vacuum.c new file mode 100644 index 0000000..6ce5dfc --- /dev/null +++ b/src/coredump/coredump-vacuum.c @@ -0,0 +1,245 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <sys/statvfs.h> + +#include "alloc-util.h" +#include "coredump-vacuum.h" +#include "dirent-util.h" +#include "fd-util.h" +#include "fs-util.h" +#include "hashmap.h" +#include "macro.h" +#include "string-util.h" +#include "time-util.h" +#include "user-util.h" +#include "util.h" + +#define DEFAULT_MAX_USE_LOWER (uint64_t) (1ULL*1024ULL*1024ULL) /* 1 MiB */ +#define DEFAULT_MAX_USE_UPPER (uint64_t) (4ULL*1024ULL*1024ULL*1024ULL) /* 4 GiB */ +#define DEFAULT_KEEP_FREE_UPPER (uint64_t) (4ULL*1024ULL*1024ULL*1024ULL) /* 4 GiB */ +#define DEFAULT_KEEP_FREE (uint64_t) (1024ULL*1024ULL) /* 1 MB */ + +struct vacuum_candidate { + unsigned n_files; + char *oldest_file; + usec_t oldest_mtime; +}; + +static void vacuum_candidate_free(struct vacuum_candidate *c) { + if (!c) + return; + + free(c->oldest_file); + free(c); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(struct vacuum_candidate*, vacuum_candidate_free); + +static void vacuum_candidate_hashmap_free(Hashmap *h) { + hashmap_free_with_destructor(h, vacuum_candidate_free); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(Hashmap*, vacuum_candidate_hashmap_free); + +static int uid_from_file_name(const char *filename, uid_t *uid) { + const char *p, *e, *u; + + p = startswith(filename, "core."); + if (!p) + return -EINVAL; + + /* Skip the comm field */ + p = strchr(p, '.'); + if (!p) + return -EINVAL; + p++; + + /* Find end up UID */ + e = strchr(p, '.'); + if (!e) + return -EINVAL; + + u = strndupa(p, e-p); + return parse_uid(u, uid); +} + +static bool vacuum_necessary(int fd, uint64_t sum, uint64_t keep_free, uint64_t max_use) { + uint64_t fs_size = 0, fs_free = (uint64_t) -1; + struct statvfs sv; + + assert(fd >= 0); + + if (fstatvfs(fd, &sv) >= 0) { + fs_size = sv.f_frsize * sv.f_blocks; + fs_free = sv.f_frsize * sv.f_bfree; + } + + if (max_use == (uint64_t) -1) { + + if (fs_size > 0) { + max_use = PAGE_ALIGN(fs_size / 10); /* 10% */ + + if (max_use > DEFAULT_MAX_USE_UPPER) + max_use = DEFAULT_MAX_USE_UPPER; + + if (max_use < DEFAULT_MAX_USE_LOWER) + max_use = DEFAULT_MAX_USE_LOWER; + } else + max_use = DEFAULT_MAX_USE_LOWER; + } else + max_use = PAGE_ALIGN(max_use); + + if (max_use > 0 && sum > max_use) + return true; + + if (keep_free == (uint64_t) -1) { + + if (fs_size > 0) { + keep_free = PAGE_ALIGN((fs_size * 3) / 20); /* 15% */ + + if (keep_free > DEFAULT_KEEP_FREE_UPPER) + keep_free = DEFAULT_KEEP_FREE_UPPER; + } else + keep_free = DEFAULT_KEEP_FREE; + } else + keep_free = PAGE_ALIGN(keep_free); + + if (keep_free > 0 && fs_free < keep_free) + return true; + + return false; +} + +int coredump_vacuum(int exclude_fd, uint64_t keep_free, uint64_t max_use) { + _cleanup_closedir_ DIR *d = NULL; + struct stat exclude_st; + int r; + + if (keep_free == 0 && max_use == 0) + return 0; + + if (exclude_fd >= 0) { + if (fstat(exclude_fd, &exclude_st) < 0) + return log_error_errno(errno, "Failed to fstat(): %m"); + } + + /* This algorithm will keep deleting the oldest file of the + * user with the most coredumps until we are back in the size + * limits. Note that vacuuming for journal files is different, + * because we rely on rate-limiting of the messages there, + * to avoid being flooded. */ + + d = opendir("/var/lib/systemd/coredump"); + if (!d) { + if (errno == ENOENT) + return 0; + + return log_error_errno(errno, "Can't open coredump directory: %m"); + } + + for (;;) { + _cleanup_(vacuum_candidate_hashmap_freep) Hashmap *h = NULL; + struct vacuum_candidate *worst = NULL; + struct dirent *de; + uint64_t sum = 0; + + rewinddir(d); + + FOREACH_DIRENT(de, d, goto fail) { + struct vacuum_candidate *c; + struct stat st; + uid_t uid; + usec_t t; + + r = uid_from_file_name(de->d_name, &uid); + if (r < 0) + continue; + + if (fstatat(dirfd(d), de->d_name, &st, AT_NO_AUTOMOUNT|AT_SYMLINK_NOFOLLOW) < 0) { + if (errno == ENOENT) + continue; + + log_warning_errno(errno, "Failed to stat /var/lib/systemd/coredump/%s: %m", de->d_name); + continue; + } + + if (!S_ISREG(st.st_mode)) + continue; + + if (exclude_fd >= 0 && + exclude_st.st_dev == st.st_dev && + exclude_st.st_ino == st.st_ino) + continue; + + r = hashmap_ensure_allocated(&h, NULL); + if (r < 0) + return log_oom(); + + t = timespec_load(&st.st_mtim); + + c = hashmap_get(h, UID_TO_PTR(uid)); + if (c) { + + if (t < c->oldest_mtime) { + char *n; + + n = strdup(de->d_name); + if (!n) + return log_oom(); + + free(c->oldest_file); + c->oldest_file = n; + c->oldest_mtime = t; + } + + } else { + _cleanup_(vacuum_candidate_freep) struct vacuum_candidate *n = NULL; + + n = new0(struct vacuum_candidate, 1); + if (!n) + return log_oom(); + + n->oldest_file = strdup(de->d_name); + if (!n->oldest_file) + return log_oom(); + + n->oldest_mtime = t; + + r = hashmap_put(h, UID_TO_PTR(uid), n); + if (r < 0) + return log_oom(); + + c = TAKE_PTR(n); + } + + c->n_files++; + + if (!worst || + worst->n_files < c->n_files || + (worst->n_files == c->n_files && c->oldest_mtime < worst->oldest_mtime)) + worst = c; + + sum += st.st_blocks * 512; + } + + if (!worst) + break; + + r = vacuum_necessary(dirfd(d), sum, keep_free, max_use); + if (r <= 0) + return r; + + r = unlinkat_deallocate(dirfd(d), worst->oldest_file, 0); + if (r == -ENOENT) + continue; + if (r < 0) + return log_error_errno(r, "Failed to remove file %s: %m", worst->oldest_file); + + log_info("Removed old coredump %s.", worst->oldest_file); + } + + return 0; + +fail: + return log_error_errno(errno, "Failed to read directory: %m"); +} diff --git a/src/coredump/coredump-vacuum.h b/src/coredump/coredump-vacuum.h new file mode 100644 index 0000000..0db1167 --- /dev/null +++ b/src/coredump/coredump-vacuum.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +#include <inttypes.h> +#include <sys/types.h> + +int coredump_vacuum(int exclude_fd, uint64_t keep_free, uint64_t max_use); diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c new file mode 100644 index 0000000..ecbb4bf --- /dev/null +++ b/src/coredump/coredump.c @@ -0,0 +1,1405 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <errno.h> +#include <stdio.h> +#include <stdio_ext.h> +#include <sys/prctl.h> +#include <sys/xattr.h> +#include <unistd.h> + +#if HAVE_ELFUTILS +#include <dwarf.h> +#include <elfutils/libdwfl.h> +#endif + +#include "sd-daemon.h" +#include "sd-journal.h" +#include "sd-login.h" +#include "sd-messages.h" + +#include "acl-util.h" +#include "alloc-util.h" +#include "capability-util.h" +#include "cgroup-util.h" +#include "compress.h" +#include "conf-parser.h" +#include "copy.h" +#include "coredump-vacuum.h" +#include "dirent-util.h" +#include "escape.h" +#include "fd-util.h" +#include "fileio.h" +#include "fs-util.h" +#include "io-util.h" +#include "journal-importer.h" +#include "log.h" +#include "macro.h" +#include "main-func.h" +#include "missing.h" +#include "mkdir.h" +#include "parse-util.h" +#include "process-util.h" +#include "signal-util.h" +#include "socket-util.h" +#include "special.h" +#include "stacktrace.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "tmpfile-util.h" +#include "user-util.h" +#include "util.h" + +/* The maximum size up to which we process coredumps */ +#define PROCESS_SIZE_MAX ((uint64_t) (2LLU*1024LLU*1024LLU*1024LLU)) + +/* The maximum size up to which we leave the coredump around on disk */ +#define EXTERNAL_SIZE_MAX PROCESS_SIZE_MAX + +/* The maximum size up to which we store the coredump in the journal */ +#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION +#define JOURNAL_SIZE_MAX ((size_t) (767LU*1024LU*1024LU)) +#else +/* oss-fuzz limits memory usage. */ +#define JOURNAL_SIZE_MAX ((size_t) (10LU*1024LU*1024LU)) +#endif + +/* Make sure to not make this larger than the maximum journal entry + * size. See DATA_SIZE_MAX in journal-importer.h. */ +assert_cc(JOURNAL_SIZE_MAX <= DATA_SIZE_MAX); + +enum { + /* We use this as array indexes for a couple of special fields we use for + * naming coredump files, and attaching xattrs, and for indexing argv[]. + + * Our pattern for man:systectl(1) kernel.core_pattern is such that the + * kernel passes fields until CONTEXT_RLIMIT as arguments in argv[]. After + * that it gets complicated: the kernel passes "comm" as one or more fields + * starting at index CONTEXT_COMM (in other words, full "comm" is under index + * CONTEXT_COMM when it does not contain spaces, which is the common + * case). This mapping is not reversible, so we prefer to retrieve "comm" + * from /proc. We only fall back to argv[CONTEXT_COMM...] when that fails. + * + * In the internal context[] array, fields before CONTEXT_COMM are the + * strings from argv[], so they should not be freed. The strings at indices + * CONTEXT_COMM and higher are allocated by us and should be freed at the + * end. + */ + CONTEXT_PID, + CONTEXT_UID, + CONTEXT_GID, + CONTEXT_SIGNAL, + CONTEXT_TIMESTAMP, + CONTEXT_RLIMIT, + CONTEXT_HOSTNAME, + CONTEXT_COMM, + CONTEXT_EXE, + CONTEXT_UNIT, + _CONTEXT_MAX +}; + +typedef enum CoredumpStorage { + COREDUMP_STORAGE_NONE, + COREDUMP_STORAGE_EXTERNAL, + COREDUMP_STORAGE_JOURNAL, + _COREDUMP_STORAGE_MAX, + _COREDUMP_STORAGE_INVALID = -1 +} CoredumpStorage; + +static const char* const coredump_storage_table[_COREDUMP_STORAGE_MAX] = { + [COREDUMP_STORAGE_NONE] = "none", + [COREDUMP_STORAGE_EXTERNAL] = "external", + [COREDUMP_STORAGE_JOURNAL] = "journal", +}; + +DEFINE_PRIVATE_STRING_TABLE_LOOKUP(coredump_storage, CoredumpStorage); +static DEFINE_CONFIG_PARSE_ENUM(config_parse_coredump_storage, coredump_storage, CoredumpStorage, "Failed to parse storage setting"); + +static CoredumpStorage arg_storage = COREDUMP_STORAGE_EXTERNAL; +static bool arg_compress = true; +static uint64_t arg_process_size_max = PROCESS_SIZE_MAX; +static uint64_t arg_external_size_max = EXTERNAL_SIZE_MAX; +static uint64_t arg_journal_size_max = JOURNAL_SIZE_MAX; +static uint64_t arg_keep_free = (uint64_t) -1; +static uint64_t arg_max_use = (uint64_t) -1; + +static int parse_config(void) { + static const ConfigTableItem items[] = { + { "Coredump", "Storage", config_parse_coredump_storage, 0, &arg_storage }, + { "Coredump", "Compress", config_parse_bool, 0, &arg_compress }, + { "Coredump", "ProcessSizeMax", config_parse_iec_uint64, 0, &arg_process_size_max }, + { "Coredump", "ExternalSizeMax", config_parse_iec_uint64, 0, &arg_external_size_max }, + { "Coredump", "JournalSizeMax", config_parse_iec_size, 0, &arg_journal_size_max }, + { "Coredump", "KeepFree", config_parse_iec_uint64, 0, &arg_keep_free }, + { "Coredump", "MaxUse", config_parse_iec_uint64, 0, &arg_max_use }, + {} + }; + + return config_parse_many_nulstr(PKGSYSCONFDIR "/coredump.conf", + CONF_PATHS_NULSTR("systemd/coredump.conf.d"), + "Coredump\0", + config_item_table_lookup, items, + CONFIG_PARSE_WARN, NULL); +} + +static uint64_t storage_size_max(void) { + if (arg_storage == COREDUMP_STORAGE_EXTERNAL) + return arg_external_size_max; + if (arg_storage == COREDUMP_STORAGE_JOURNAL) + return arg_journal_size_max; + assert(arg_storage == COREDUMP_STORAGE_NONE); + return 0; +} + +static int fix_acl(int fd, uid_t uid) { + +#if HAVE_ACL + _cleanup_(acl_freep) acl_t acl = NULL; + acl_entry_t entry; + acl_permset_t permset; + int r; + + assert(fd >= 0); + + if (uid_is_system(uid) || uid_is_dynamic(uid) || uid == UID_NOBODY) + return 0; + + /* Make sure normal users can read (but not write or delete) + * their own coredumps */ + + acl = acl_get_fd(fd); + if (!acl) + return log_error_errno(errno, "Failed to get ACL: %m"); + + if (acl_create_entry(&acl, &entry) < 0 || + acl_set_tag_type(entry, ACL_USER) < 0 || + acl_set_qualifier(entry, &uid) < 0) + return log_error_errno(errno, "Failed to patch ACL: %m"); + + if (acl_get_permset(entry, &permset) < 0 || + acl_add_perm(permset, ACL_READ) < 0) + return log_warning_errno(errno, "Failed to patch ACL: %m"); + + r = calc_acl_mask_if_needed(&acl); + if (r < 0) + return log_warning_errno(r, "Failed to patch ACL: %m"); + + if (acl_set_fd(fd, acl) < 0) + return log_error_errno(errno, "Failed to apply ACL: %m"); +#endif + + return 0; +} + +static int fix_xattr(int fd, const char *context[_CONTEXT_MAX]) { + + static const char * const xattrs[_CONTEXT_MAX] = { + [CONTEXT_PID] = "user.coredump.pid", + [CONTEXT_UID] = "user.coredump.uid", + [CONTEXT_GID] = "user.coredump.gid", + [CONTEXT_SIGNAL] = "user.coredump.signal", + [CONTEXT_TIMESTAMP] = "user.coredump.timestamp", + [CONTEXT_RLIMIT] = "user.coredump.rlimit", + [CONTEXT_HOSTNAME] = "user.coredump.hostname", + [CONTEXT_COMM] = "user.coredump.comm", + [CONTEXT_EXE] = "user.coredump.exe", + }; + + int r = 0; + unsigned i; + + assert(fd >= 0); + + /* Attach some metadata to coredumps via extended + * attributes. Just because we can. */ + + for (i = 0; i < _CONTEXT_MAX; i++) { + int k; + + if (isempty(context[i]) || !xattrs[i]) + continue; + + k = fsetxattr(fd, xattrs[i], context[i], strlen(context[i]), XATTR_CREATE); + if (k < 0 && r == 0) + r = -errno; + } + + return r; +} + +#define filename_escape(s) xescape((s), "./ ") + +static const char *coredump_tmpfile_name(const char *s) { + return s ? s : "(unnamed temporary file)"; +} + +static int fix_permissions( + int fd, + const char *filename, + const char *target, + const char *context[_CONTEXT_MAX], + uid_t uid) { + + int r; + + assert(fd >= 0); + assert(target); + assert(context); + + /* Ignore errors on these */ + (void) fchmod(fd, 0640); + (void) fix_acl(fd, uid); + (void) fix_xattr(fd, context); + + if (fsync(fd) < 0) + return log_error_errno(errno, "Failed to sync coredump %s: %m", coredump_tmpfile_name(filename)); + + (void) fsync_directory_of_file(fd); + + r = link_tmpfile(fd, filename, target); + if (r < 0) + return log_error_errno(r, "Failed to move coredump %s into place: %m", target); + + return 0; +} + +static int maybe_remove_external_coredump(const char *filename, uint64_t size) { + + /* Returns 1 if might remove, 0 if will not remove, < 0 on error. */ + + if (arg_storage == COREDUMP_STORAGE_EXTERNAL && + size <= arg_external_size_max) + return 0; + + if (!filename) + return 1; + + if (unlink(filename) < 0 && errno != ENOENT) + return log_error_errno(errno, "Failed to unlink %s: %m", filename); + + return 1; +} + +static int make_filename(const char *context[_CONTEXT_MAX], char **ret) { + _cleanup_free_ char *c = NULL, *u = NULL, *p = NULL, *t = NULL; + sd_id128_t boot = {}; + int r; + + assert(context); + + c = filename_escape(context[CONTEXT_COMM]); + if (!c) + return -ENOMEM; + + u = filename_escape(context[CONTEXT_UID]); + if (!u) + return -ENOMEM; + + r = sd_id128_get_boot(&boot); + if (r < 0) + return r; + + p = filename_escape(context[CONTEXT_PID]); + if (!p) + return -ENOMEM; + + t = filename_escape(context[CONTEXT_TIMESTAMP]); + if (!t) + return -ENOMEM; + + if (asprintf(ret, + "/var/lib/systemd/coredump/core.%s.%s." SD_ID128_FORMAT_STR ".%s.%s000000", + c, + u, + SD_ID128_FORMAT_VAL(boot), + p, + t) < 0) + return -ENOMEM; + + return 0; +} + +static int save_external_coredump( + const char *context[_CONTEXT_MAX], + int input_fd, + char **ret_filename, + int *ret_node_fd, + int *ret_data_fd, + uint64_t *ret_size, + bool *ret_truncated) { + + _cleanup_free_ char *fn = NULL, *tmp = NULL; + _cleanup_close_ int fd = -1; + uint64_t rlimit, process_limit, max_size; + struct stat st; + uid_t uid; + int r; + + assert(context); + assert(ret_filename); + assert(ret_node_fd); + assert(ret_data_fd); + assert(ret_size); + + r = parse_uid(context[CONTEXT_UID], &uid); + if (r < 0) + return log_error_errno(r, "Failed to parse UID: %m"); + + r = safe_atou64(context[CONTEXT_RLIMIT], &rlimit); + if (r < 0) + return log_error_errno(r, "Failed to parse resource limit '%s': %m", context[CONTEXT_RLIMIT]); + if (rlimit < page_size()) { + /* Is coredumping disabled? Then don't bother saving/processing the coredump. + * Anything below PAGE_SIZE cannot give a readable coredump (the kernel uses + * ELF_EXEC_PAGESIZE which is not easily accessible, but is usually the same as PAGE_SIZE. */ + return log_info_errno(SYNTHETIC_ERRNO(EBADSLT), + "Resource limits disable core dumping for process %s (%s).", + context[CONTEXT_PID], context[CONTEXT_COMM]); + } + + process_limit = MAX(arg_process_size_max, storage_size_max()); + if (process_limit == 0) + return log_debug_errno(SYNTHETIC_ERRNO(EBADSLT), + "Limits for coredump processing and storage are both 0, not dumping core."); + + /* Never store more than the process configured, or than we actually shall keep or process */ + max_size = MIN(rlimit, process_limit); + + r = make_filename(context, &fn); + if (r < 0) + return log_error_errno(r, "Failed to determine coredump file name: %m"); + + mkdir_p_label("/var/lib/systemd/coredump", 0755); + + fd = open_tmpfile_linkable(fn, O_RDWR|O_CLOEXEC, &tmp); + if (fd < 0) + return log_error_errno(fd, "Failed to create temporary file for coredump %s: %m", fn); + + r = copy_bytes(input_fd, fd, max_size, 0); + if (r < 0) { + log_error_errno(r, "Cannot store coredump of %s (%s): %m", context[CONTEXT_PID], context[CONTEXT_COMM]); + goto fail; + } + *ret_truncated = r == 1; + if (*ret_truncated) + log_struct(LOG_INFO, + LOG_MESSAGE("Core file was truncated to %zu bytes.", max_size), + "SIZE_LIMIT=%zu", max_size, + "MESSAGE_ID=" SD_MESSAGE_TRUNCATED_CORE_STR); + + if (fstat(fd, &st) < 0) { + log_error_errno(errno, "Failed to fstat core file %s: %m", coredump_tmpfile_name(tmp)); + goto fail; + } + + if (lseek(fd, 0, SEEK_SET) == (off_t) -1) { + log_error_errno(errno, "Failed to seek on %s: %m", coredump_tmpfile_name(tmp)); + goto fail; + } + +#if HAVE_XZ || HAVE_LZ4 + /* If we will remove the coredump anyway, do not compress. */ + if (arg_compress && !maybe_remove_external_coredump(NULL, st.st_size)) { + + _cleanup_free_ char *fn_compressed = NULL, *tmp_compressed = NULL; + _cleanup_close_ int fd_compressed = -1; + + fn_compressed = strappend(fn, COMPRESSED_EXT); + if (!fn_compressed) { + log_oom(); + goto uncompressed; + } + + fd_compressed = open_tmpfile_linkable(fn_compressed, O_RDWR|O_CLOEXEC, &tmp_compressed); + if (fd_compressed < 0) { + log_error_errno(fd_compressed, "Failed to create temporary file for coredump %s: %m", fn_compressed); + goto uncompressed; + } + + r = compress_stream(fd, fd_compressed, -1); + if (r < 0) { + log_error_errno(r, "Failed to compress %s: %m", coredump_tmpfile_name(tmp_compressed)); + goto fail_compressed; + } + + r = fix_permissions(fd_compressed, tmp_compressed, fn_compressed, context, uid); + if (r < 0) + goto fail_compressed; + + /* OK, this worked, we can get rid of the uncompressed version now */ + if (tmp) + unlink_noerrno(tmp); + + *ret_filename = TAKE_PTR(fn_compressed); /* compressed */ + *ret_node_fd = TAKE_FD(fd_compressed); /* compressed */ + *ret_data_fd = TAKE_FD(fd); /* uncompressed */ + *ret_size = (uint64_t) st.st_size; /* uncompressed */ + + return 0; + + fail_compressed: + if (tmp_compressed) + (void) unlink(tmp_compressed); + } + +uncompressed: +#endif + + r = fix_permissions(fd, tmp, fn, context, uid); + if (r < 0) + goto fail; + + *ret_filename = TAKE_PTR(fn); + *ret_data_fd = TAKE_FD(fd); + *ret_node_fd = -1; + *ret_size = (uint64_t) st.st_size; + + return 0; + +fail: + if (tmp) + (void) unlink(tmp); + return r; +} + +static int allocate_journal_field(int fd, size_t size, char **ret, size_t *ret_size) { + _cleanup_free_ char *field = NULL; + ssize_t n; + + assert(fd >= 0); + assert(ret); + assert(ret_size); + + if (lseek(fd, 0, SEEK_SET) == (off_t) -1) + return log_warning_errno(errno, "Failed to seek: %m"); + + field = malloc(9 + size); + if (!field) { + log_warning("Failed to allocate memory for coredump, coredump will not be stored."); + return -ENOMEM; + } + + memcpy(field, "COREDUMP=", 9); + + n = read(fd, field + 9, size); + if (n < 0) + return log_error_errno((int) n, "Failed to read core data: %m"); + if ((size_t) n < size) + return log_error_errno(SYNTHETIC_ERRNO(EIO), + "Core data too short."); + + *ret = TAKE_PTR(field); + *ret_size = size + 9; + + return 0; +} + +/* Joins /proc/[pid]/fd/ and /proc/[pid]/fdinfo/ into the following lines: + * 0:/dev/pts/23 + * pos: 0 + * flags: 0100002 + * + * 1:/dev/pts/23 + * pos: 0 + * flags: 0100002 + * + * 2:/dev/pts/23 + * pos: 0 + * flags: 0100002 + * EOF + */ +static int compose_open_fds(pid_t pid, char **open_fds) { + _cleanup_closedir_ DIR *proc_fd_dir = NULL; + _cleanup_close_ int proc_fdinfo_fd = -1; + _cleanup_free_ char *buffer = NULL; + _cleanup_fclose_ FILE *stream = NULL; + const char *fddelim = "", *path; + struct dirent *dent = NULL; + size_t size = 0; + int r; + + assert(pid >= 0); + assert(open_fds != NULL); + + path = procfs_file_alloca(pid, "fd"); + proc_fd_dir = opendir(path); + if (!proc_fd_dir) + return -errno; + + proc_fdinfo_fd = openat(dirfd(proc_fd_dir), "../fdinfo", O_DIRECTORY|O_NOFOLLOW|O_CLOEXEC|O_PATH); + if (proc_fdinfo_fd < 0) + return -errno; + + stream = open_memstream(&buffer, &size); + if (!stream) + return -ENOMEM; + + (void) __fsetlocking(stream, FSETLOCKING_BYCALLER); + + FOREACH_DIRENT(dent, proc_fd_dir, return -errno) { + _cleanup_fclose_ FILE *fdinfo = NULL; + _cleanup_free_ char *fdname = NULL; + int fd; + + r = readlinkat_malloc(dirfd(proc_fd_dir), dent->d_name, &fdname); + if (r < 0) + return r; + + fprintf(stream, "%s%s:%s\n", fddelim, dent->d_name, fdname); + fddelim = "\n"; + + /* Use the directory entry from /proc/[pid]/fd with /proc/[pid]/fdinfo */ + fd = openat(proc_fdinfo_fd, dent->d_name, O_NOFOLLOW|O_CLOEXEC|O_RDONLY); + if (fd < 0) + continue; + + fdinfo = fdopen(fd, "r"); + if (!fdinfo) { + safe_close(fd); + continue; + } + + for (;;) { + _cleanup_free_ char *line = NULL; + + r = read_line(fdinfo, LONG_LINE_MAX, &line); + if (r < 0) + return r; + if (r == 0) + break; + + fputs(line, stream); + fputc('\n', stream); + } + } + + errno = 0; + stream = safe_fclose(stream); + + if (errno > 0) + return -errno; + + *open_fds = TAKE_PTR(buffer); + + return 0; +} + +static int get_process_ns(pid_t pid, const char *namespace, ino_t *ns) { + const char *p; + struct stat stbuf; + _cleanup_close_ int proc_ns_dir_fd; + + p = procfs_file_alloca(pid, "ns"); + + proc_ns_dir_fd = open(p, O_DIRECTORY | O_CLOEXEC | O_RDONLY); + if (proc_ns_dir_fd < 0) + return -errno; + + if (fstatat(proc_ns_dir_fd, namespace, &stbuf, /* flags */0) < 0) + return -errno; + + *ns = stbuf.st_ino; + return 0; +} + +static int get_mount_namespace_leader(pid_t pid, pid_t *container_pid) { + pid_t cpid = pid, ppid = 0; + ino_t proc_mntns; + int r = 0; + + r = get_process_ns(pid, "mnt", &proc_mntns); + if (r < 0) + return r; + + for (;;) { + ino_t parent_mntns; + + r = get_process_ppid(cpid, &ppid); + if (r < 0) + return r; + + r = get_process_ns(ppid, "mnt", &parent_mntns); + if (r < 0) + return r; + + if (proc_mntns != parent_mntns) + break; + + if (ppid == 1) + return -ENOENT; + + cpid = ppid; + } + + *container_pid = ppid; + return 0; +} + +/* Returns 1 if the parent was found. + * Returns 0 if there is not a process we can call the pid's + * container parent (the pid's process isn't 'containerized'). + * Returns a negative number on errors. + */ +static int get_process_container_parent_cmdline(pid_t pid, char** cmdline) { + int r = 0; + pid_t container_pid; + const char *proc_root_path; + struct stat root_stat, proc_root_stat; + + /* To compare inodes of / and /proc/[pid]/root */ + if (stat("/", &root_stat) < 0) + return -errno; + + proc_root_path = procfs_file_alloca(pid, "root"); + if (stat(proc_root_path, &proc_root_stat) < 0) + return -errno; + + /* The process uses system root. */ + if (proc_root_stat.st_ino == root_stat.st_ino) { + *cmdline = NULL; + return 0; + } + + r = get_mount_namespace_leader(pid, &container_pid); + if (r < 0) + return r; + + r = get_process_cmdline(container_pid, 0, false, cmdline); + if (r < 0) + return r; + + return 1; +} + +static int change_uid_gid(const char *context[]) { + uid_t uid; + gid_t gid; + int r; + + r = parse_uid(context[CONTEXT_UID], &uid); + if (r < 0) + return r; + + if (uid <= SYSTEM_UID_MAX) { + const char *user = "systemd-coredump"; + + r = get_user_creds(&user, &uid, &gid, NULL, NULL, 0); + if (r < 0) { + log_warning_errno(r, "Cannot resolve %s user. Proceeding to dump core as root: %m", user); + uid = gid = 0; + } + } else { + r = parse_gid(context[CONTEXT_GID], &gid); + if (r < 0) + return r; + } + + return drop_privileges(uid, gid, 0); +} + +static bool is_journald_crash(const char *context[_CONTEXT_MAX]) { + assert(context); + + return streq_ptr(context[CONTEXT_UNIT], SPECIAL_JOURNALD_SERVICE); +} + +static bool is_pid1_crash(const char *context[_CONTEXT_MAX]) { + assert(context); + + return streq_ptr(context[CONTEXT_UNIT], SPECIAL_INIT_SCOPE) || + streq_ptr(context[CONTEXT_PID], "1"); +} + +#define SUBMIT_COREDUMP_FIELDS 4 + +static int submit_coredump( + const char *context[_CONTEXT_MAX], + struct iovec *iovec, + size_t n_iovec_allocated, + size_t n_iovec, + int input_fd) { + + _cleanup_close_ int coredump_fd = -1, coredump_node_fd = -1; + _cleanup_free_ char *core_message = NULL, *filename = NULL, *coredump_data = NULL; + uint64_t coredump_size = UINT64_MAX; + bool truncated = false, journald_crash; + int r; + + assert(context); + assert(iovec); + assert(n_iovec_allocated >= n_iovec + SUBMIT_COREDUMP_FIELDS); + assert(input_fd >= 0); + + journald_crash = is_journald_crash(context); + + /* Vacuum before we write anything again */ + (void) coredump_vacuum(-1, arg_keep_free, arg_max_use); + + /* Always stream the coredump to disk, if that's possible */ + r = save_external_coredump(context, input_fd, + &filename, &coredump_node_fd, &coredump_fd, &coredump_size, &truncated); + if (r < 0) + /* Skip whole core dumping part */ + goto log; + + /* If we don't want to keep the coredump on disk, remove it now, as later on we will lack the privileges for + * it. However, we keep the fd to it, so that we can still process it and log it. */ + r = maybe_remove_external_coredump(filename, coredump_size); + if (r < 0) + return r; + if (r == 0) { + const char *coredump_filename; + + coredump_filename = strjoina("COREDUMP_FILENAME=", filename); + iovec[n_iovec++] = IOVEC_MAKE_STRING(coredump_filename); + } else if (arg_storage == COREDUMP_STORAGE_EXTERNAL) + log_info("The core will not be stored: size %"PRIu64" is greater than %"PRIu64" (the configured maximum)", + coredump_size, arg_external_size_max); + + /* Vacuum again, but exclude the coredump we just created */ + (void) coredump_vacuum(coredump_node_fd >= 0 ? coredump_node_fd : coredump_fd, arg_keep_free, arg_max_use); + + /* Now, let's drop privileges to become the user who owns the segfaulted process and allocate the coredump + * memory under the user's uid. This also ensures that the credentials journald will see are the ones of the + * coredumping user, thus making sure the user gets access to the core dump. Let's also get rid of all + * capabilities, if we run as root, we won't need them anymore. */ + r = change_uid_gid(context); + if (r < 0) + return log_error_errno(r, "Failed to drop privileges: %m"); + +#if HAVE_ELFUTILS + /* Try to get a strack trace if we can */ + if (coredump_size <= arg_process_size_max) { + _cleanup_free_ char *stacktrace = NULL; + + r = coredump_make_stack_trace(coredump_fd, context[CONTEXT_EXE], &stacktrace); + if (r >= 0) + core_message = strjoin("MESSAGE=Process ", context[CONTEXT_PID], + " (", context[CONTEXT_COMM], ") of user ", + context[CONTEXT_UID], " dumped core.", + journald_crash ? "\nCoredump diverted to " : "", + journald_crash ? filename : "", + "\n\n", stacktrace); + else if (r == -EINVAL) + log_warning("Failed to generate stack trace: %s", dwfl_errmsg(dwfl_errno())); + else + log_warning_errno(r, "Failed to generate stack trace: %m"); + } else + log_debug("Not generating stack trace: core size %"PRIu64" is greater than %"PRIu64" (the configured maximum)", + coredump_size, arg_process_size_max); + + if (!core_message) +#endif +log: + core_message = strjoin("MESSAGE=Process ", context[CONTEXT_PID], + " (", context[CONTEXT_COMM], ") of user ", + context[CONTEXT_UID], " dumped core.", + journald_crash && filename ? "\nCoredump diverted to " : NULL, + journald_crash && filename ? filename : NULL); + if (!core_message) + return log_oom(); + + if (journald_crash) { + /* We cannot log to the journal, so just print the message. + * The target was set previously to something safe. */ + assert(startswith(core_message, "MESSAGE=")); + log_dispatch(LOG_ERR, 0, core_message + strlen("MESSAGE=")); + return 0; + } + + iovec[n_iovec++] = IOVEC_MAKE_STRING(core_message); + + if (truncated) + iovec[n_iovec++] = IOVEC_MAKE_STRING("COREDUMP_TRUNCATED=1"); + + /* Optionally store the entire coredump in the journal */ + if (arg_storage == COREDUMP_STORAGE_JOURNAL) { + if (coredump_size <= arg_journal_size_max) { + size_t sz = 0; + + /* Store the coredump itself in the journal */ + + r = allocate_journal_field(coredump_fd, (size_t) coredump_size, &coredump_data, &sz); + if (r >= 0) + iovec[n_iovec++] = IOVEC_MAKE(coredump_data, sz); + else + log_warning_errno(r, "Failed to attach the core to the journal entry: %m"); + } else + log_info("The core will not be stored: size %"PRIu64" is greater than %"PRIu64" (the configured maximum)", + coredump_size, arg_journal_size_max); + } + + assert(n_iovec <= n_iovec_allocated); + + r = sd_journal_sendv(iovec, n_iovec); + if (r < 0) + return log_error_errno(r, "Failed to log coredump: %m"); + + return 0; +} + +static void map_context_fields(const struct iovec *iovec, const char* context[]) { + + static const char * const context_field_names[] = { + [CONTEXT_PID] = "COREDUMP_PID=", + [CONTEXT_UID] = "COREDUMP_UID=", + [CONTEXT_GID] = "COREDUMP_GID=", + [CONTEXT_SIGNAL] = "COREDUMP_SIGNAL=", + [CONTEXT_TIMESTAMP] = "COREDUMP_TIMESTAMP=", + [CONTEXT_RLIMIT] = "COREDUMP_RLIMIT=", + [CONTEXT_HOSTNAME] = "COREDUMP_HOSTNAME=", + [CONTEXT_COMM] = "COREDUMP_COMM=", + [CONTEXT_EXE] = "COREDUMP_EXE=", + }; + + unsigned i; + + assert(iovec); + assert(context); + + for (i = 0; i < ELEMENTSOF(context_field_names); i++) { + char *p; + + if (!context_field_names[i]) + continue; + + p = memory_startswith(iovec->iov_base, iovec->iov_len, context_field_names[i]); + if (!p) + continue; + + /* Note that these strings are NUL terminated, because we made sure that a trailing NUL byte is in the + * buffer, though not included in the iov_len count. (see below) */ + context[i] = p; + break; + } +} + +static int process_socket(int fd) { + _cleanup_close_ int coredump_fd = -1; + struct iovec *iovec = NULL; + size_t n_iovec = 0, n_allocated = 0, i, k; + const char *context[_CONTEXT_MAX] = {}; + int r; + + assert(fd >= 0); + + log_setup_service(); + + log_debug("Processing coredump received on stdin..."); + + for (;;) { + union { + struct cmsghdr cmsghdr; + uint8_t buf[CMSG_SPACE(sizeof(int))]; + } control = {}; + struct msghdr mh = { + .msg_control = &control, + .msg_controllen = sizeof(control), + .msg_iovlen = 1, + }; + ssize_t n; + ssize_t l; + + if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + SUBMIT_COREDUMP_FIELDS)) { + r = log_oom(); + goto finish; + } + + l = next_datagram_size_fd(fd); + if (l < 0) { + r = log_error_errno(l, "Failed to determine datagram size to read: %m"); + goto finish; + } + + assert(l >= 0); + + iovec[n_iovec].iov_len = l; + iovec[n_iovec].iov_base = malloc(l + 1); + if (!iovec[n_iovec].iov_base) { + r = log_oom(); + goto finish; + } + + mh.msg_iov = iovec + n_iovec; + + n = recvmsg(fd, &mh, MSG_CMSG_CLOEXEC); + if (n < 0) { + free(iovec[n_iovec].iov_base); + r = log_error_errno(errno, "Failed to receive datagram: %m"); + goto finish; + } + + if (n == 0) { + struct cmsghdr *cmsg, *found = NULL; + /* The final zero-length datagram carries the file descriptor and tells us that we're done. */ + + free(iovec[n_iovec].iov_base); + + CMSG_FOREACH(cmsg, &mh) { + if (cmsg->cmsg_level == SOL_SOCKET && + cmsg->cmsg_type == SCM_RIGHTS && + cmsg->cmsg_len == CMSG_LEN(sizeof(int))) { + assert(!found); + found = cmsg; + } + } + + if (!found) { + log_error("Coredump file descriptor missing."); + r = -EBADMSG; + goto finish; + } + + assert(coredump_fd < 0); + coredump_fd = *(int*) CMSG_DATA(found); + break; + } + + /* Add trailing NUL byte, in case these are strings */ + ((char*) iovec[n_iovec].iov_base)[n] = 0; + iovec[n_iovec].iov_len = (size_t) n; + + cmsg_close_all(&mh); + map_context_fields(iovec + n_iovec, context); + n_iovec++; + } + + if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + SUBMIT_COREDUMP_FIELDS)) { + r = log_oom(); + goto finish; + } + + /* Make sure we got all data we really need */ + assert(context[CONTEXT_PID]); + assert(context[CONTEXT_UID]); + assert(context[CONTEXT_GID]); + assert(context[CONTEXT_SIGNAL]); + assert(context[CONTEXT_TIMESTAMP]); + assert(context[CONTEXT_RLIMIT]); + assert(context[CONTEXT_HOSTNAME]); + assert(context[CONTEXT_COMM]); + assert(coredump_fd >= 0); + + /* Small quirk: the journal fields contain the timestamp padded with six zeroes, so that the kernel-supplied 1s + * granularity timestamps becomes 1µs granularity, i.e. the granularity systemd usually operates in. Since we + * are reconstructing the original kernel context, we chop this off again, here. */ + k = strlen(context[CONTEXT_TIMESTAMP]); + if (k > 6) + context[CONTEXT_TIMESTAMP] = strndupa(context[CONTEXT_TIMESTAMP], k - 6); + + r = submit_coredump(context, iovec, n_allocated, n_iovec, coredump_fd); + +finish: + for (i = 0; i < n_iovec; i++) + free(iovec[i].iov_base); + free(iovec); + + return r; +} + +static int send_iovec(const struct iovec iovec[], size_t n_iovec, int input_fd) { + + static const union sockaddr_union sa = { + .un.sun_family = AF_UNIX, + .un.sun_path = "/run/systemd/coredump", + }; + _cleanup_close_ int fd = -1; + size_t i; + int r; + + assert(iovec || n_iovec <= 0); + assert(input_fd >= 0); + + fd = socket(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0); + if (fd < 0) + return log_error_errno(errno, "Failed to create coredump socket: %m"); + + if (connect(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) + return log_error_errno(errno, "Failed to connect to coredump service: %m"); + + for (i = 0; i < n_iovec; i++) { + struct msghdr mh = { + .msg_iov = (struct iovec*) iovec + i, + .msg_iovlen = 1, + }; + struct iovec copy[2]; + + for (;;) { + if (sendmsg(fd, &mh, MSG_NOSIGNAL) >= 0) + break; + + if (errno == EMSGSIZE && mh.msg_iov[0].iov_len > 0) { + /* This field didn't fit? That's a pity. Given that this is just metadata, + * let's truncate the field at half, and try again. We append three dots, in + * order to show that this is truncated. */ + + if (mh.msg_iov != copy) { + /* We don't want to modify the caller's iovec, hence let's create our + * own array, consisting of two new iovecs, where the first is a + * (truncated) copy of what we want to send, and the second one + * contains the trailing dots. */ + copy[0] = iovec[i]; + copy[1] = (struct iovec) { + .iov_base = (char[]) { '.', '.', '.' }, + .iov_len = 3, + }; + + mh.msg_iov = copy; + mh.msg_iovlen = 2; + } + + copy[0].iov_len /= 2; /* halve it, and try again */ + continue; + } + + return log_error_errno(errno, "Failed to send coredump datagram: %m"); + } + } + + r = send_one_fd(fd, input_fd, 0); + if (r < 0) + return log_error_errno(r, "Failed to send coredump fd: %m"); + + return 0; +} + +static char* set_iovec_field_free(struct iovec *iovec, size_t *n_iovec, const char *field, char *value) { + char *x; + + x = set_iovec_string_field(iovec, n_iovec, field, value); + free(value); + return x; +} + +static int gather_pid_metadata( + char* context[_CONTEXT_MAX], + char **comm_fallback, + struct iovec *iovec, size_t *n_iovec) { + + /* We need 27 empty slots in iovec! + * + * Note that if we fail on oom later on, we do not roll-back changes to the iovec structure. (It remains valid, + * with the first n_iovec fields initialized.) */ + + uid_t owner_uid; + pid_t pid; + char *t; + const char *p; + int r, signo; + + r = parse_pid(context[CONTEXT_PID], &pid); + if (r < 0) + return log_error_errno(r, "Failed to parse PID \"%s\": %m", context[CONTEXT_PID]); + + r = get_process_comm(pid, &context[CONTEXT_COMM]); + if (r < 0) { + log_warning_errno(r, "Failed to get COMM, falling back to the command line: %m"); + context[CONTEXT_COMM] = strv_join(comm_fallback, " "); + if (!context[CONTEXT_COMM]) + return log_oom(); + } + + r = get_process_exe(pid, &context[CONTEXT_EXE]); + if (r < 0) + log_warning_errno(r, "Failed to get EXE, ignoring: %m"); + + if (cg_pid_get_unit(pid, &context[CONTEXT_UNIT]) >= 0) { + if (!is_journald_crash((const char**) context)) { + /* OK, now we know it's not the journal, hence we can make use of it now. */ + log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); + log_open(); + } + + /* If this is PID 1 disable coredump collection, we'll unlikely be able to process it later on. */ + if (is_pid1_crash((const char**) context)) { + log_notice("Due to PID 1 having crashed coredump collection will now be turned off."); + disable_coredumps(); + } + + set_iovec_string_field(iovec, n_iovec, "COREDUMP_UNIT=", context[CONTEXT_UNIT]); + } + + if (cg_pid_get_user_unit(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_USER_UNIT=", t); + + /* The next few are mandatory */ + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_PID=", context[CONTEXT_PID])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_UID=", context[CONTEXT_UID])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_GID=", context[CONTEXT_GID])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_SIGNAL=", context[CONTEXT_SIGNAL])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_RLIMIT=", context[CONTEXT_RLIMIT])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_HOSTNAME=", context[CONTEXT_HOSTNAME])) + return log_oom(); + + if (!set_iovec_string_field(iovec, n_iovec, "COREDUMP_COMM=", context[CONTEXT_COMM])) + return log_oom(); + + if (context[CONTEXT_EXE] && + !set_iovec_string_field(iovec, n_iovec, "COREDUMP_EXE=", context[CONTEXT_EXE])) + return log_oom(); + + if (sd_pid_get_session(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_SESSION=", t); + + if (sd_pid_get_owner_uid(pid, &owner_uid) >= 0) { + r = asprintf(&t, "COREDUMP_OWNER_UID=" UID_FMT, owner_uid); + if (r > 0) + iovec[(*n_iovec)++] = IOVEC_MAKE_STRING(t); + } + + if (sd_pid_get_slice(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_SLICE=", t); + + if (get_process_cmdline(pid, 0, false, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_CMDLINE=", t); + + if (cg_pid_get_path_shifted(pid, NULL, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_CGROUP=", t); + + if (compose_open_fds(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_OPEN_FDS=", t); + + p = procfs_file_alloca(pid, "status"); + if (read_full_file(p, &t, NULL) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_PROC_STATUS=", t); + + p = procfs_file_alloca(pid, "maps"); + if (read_full_file(p, &t, NULL) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_PROC_MAPS=", t); + + p = procfs_file_alloca(pid, "limits"); + if (read_full_file(p, &t, NULL) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_PROC_LIMITS=", t); + + p = procfs_file_alloca(pid, "cgroup"); + if (read_full_file(p, &t, NULL) >=0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_PROC_CGROUP=", t); + + p = procfs_file_alloca(pid, "mountinfo"); + if (read_full_file(p, &t, NULL) >=0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_PROC_MOUNTINFO=", t); + + if (get_process_cwd(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_CWD=", t); + + if (get_process_root(pid, &t) >= 0) { + bool proc_self_root_is_slash; + + proc_self_root_is_slash = strcmp(t, "/") == 0; + + set_iovec_field_free(iovec, n_iovec, "COREDUMP_ROOT=", t); + + /* If the process' root is "/", then there is a chance it has + * mounted own root and hence being containerized. */ + if (proc_self_root_is_slash && get_process_container_parent_cmdline(pid, &t) > 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_CONTAINER_CMDLINE=", t); + } + + if (get_process_environ(pid, &t) >= 0) + set_iovec_field_free(iovec, n_iovec, "COREDUMP_ENVIRON=", t); + + t = strjoin("COREDUMP_TIMESTAMP=", context[CONTEXT_TIMESTAMP], "000000"); + if (t) + iovec[(*n_iovec)++] = IOVEC_MAKE_STRING(t); + + if (safe_atoi(context[CONTEXT_SIGNAL], &signo) >= 0 && SIGNAL_VALID(signo)) + set_iovec_string_field(iovec, n_iovec, "COREDUMP_SIGNAL_NAME=SIG", signal_to_string(signo)); + + return 0; /* we successfully acquired all metadata */ +} + +static int process_kernel(int argc, char* argv[]) { + + char* context[_CONTEXT_MAX] = {}; + struct iovec iovec[29 + SUBMIT_COREDUMP_FIELDS]; + size_t i, n_iovec, n_to_free = 0; + int r; + + log_debug("Processing coredump received from the kernel..."); + + if (argc < CONTEXT_COMM + 1) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Not enough arguments passed by the kernel (%i, expected %i).", + argc - 1, CONTEXT_COMM + 1 - 1); + + context[CONTEXT_PID] = argv[1 + CONTEXT_PID]; + context[CONTEXT_UID] = argv[1 + CONTEXT_UID]; + context[CONTEXT_GID] = argv[1 + CONTEXT_GID]; + context[CONTEXT_SIGNAL] = argv[1 + CONTEXT_SIGNAL]; + context[CONTEXT_TIMESTAMP] = argv[1 + CONTEXT_TIMESTAMP]; + context[CONTEXT_RLIMIT] = argv[1 + CONTEXT_RLIMIT]; + context[CONTEXT_HOSTNAME] = argv[1 + CONTEXT_HOSTNAME]; + + r = gather_pid_metadata(context, argv + 1 + CONTEXT_COMM, iovec, &n_to_free); + if (r < 0) + goto finish; + + n_iovec = n_to_free; + + iovec[n_iovec++] = IOVEC_MAKE_STRING("MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR); + + assert_cc(2 == LOG_CRIT); + iovec[n_iovec++] = IOVEC_MAKE_STRING("PRIORITY=2"); + + assert(n_iovec <= ELEMENTSOF(iovec)); + + if (is_journald_crash((const char**) context) || is_pid1_crash((const char**) context)) + r = submit_coredump((const char**) context, + iovec, ELEMENTSOF(iovec), n_iovec, + STDIN_FILENO); + else + r = send_iovec(iovec, n_iovec, STDIN_FILENO); + + finish: + for (i = 0; i < n_to_free; i++) + free(iovec[i].iov_base); + + /* Those fields are allocated by gather_pid_metadata */ + free(context[CONTEXT_COMM]); + free(context[CONTEXT_EXE]); + free(context[CONTEXT_UNIT]); + + return r; +} + +static int process_backtrace(int argc, char *argv[]) { + char *context[_CONTEXT_MAX] = {}; + _cleanup_free_ char *message = NULL; + _cleanup_free_ struct iovec *iovec = NULL; + size_t n_iovec, n_allocated, n_to_free = 0, i; + int r; + JournalImporter importer = { + .fd = STDIN_FILENO, + }; + + log_debug("Processing backtrace on stdin..."); + + if (argc < CONTEXT_COMM + 1) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Not enough arguments passed (%i, expected %i).", + argc - 1, CONTEXT_COMM + 1 - 1); + + context[CONTEXT_PID] = argv[2 + CONTEXT_PID]; + context[CONTEXT_UID] = argv[2 + CONTEXT_UID]; + context[CONTEXT_GID] = argv[2 + CONTEXT_GID]; + context[CONTEXT_SIGNAL] = argv[2 + CONTEXT_SIGNAL]; + context[CONTEXT_TIMESTAMP] = argv[2 + CONTEXT_TIMESTAMP]; + context[CONTEXT_RLIMIT] = argv[2 + CONTEXT_RLIMIT]; + context[CONTEXT_HOSTNAME] = argv[2 + CONTEXT_HOSTNAME]; + + n_allocated = 34 + COREDUMP_STORAGE_EXTERNAL; + /* 26 metadata, 2 static, +unknown input, 4 storage, rounded up */ + iovec = new(struct iovec, n_allocated); + if (!iovec) + return log_oom(); + + r = gather_pid_metadata(context, argv + 2 + CONTEXT_COMM, iovec, &n_to_free); + if (r < 0) + goto finish; + if (r > 0) { + /* This was a special crash, and has already been processed. */ + r = 0; + goto finish; + } + n_iovec = n_to_free; + + for (;;) { + r = journal_importer_process_data(&importer); + if (r < 0) { + log_error_errno(r, "Failed to parse journal entry on stdin: %m"); + goto finish; + } + if (r == 1 || /* complete entry */ + journal_importer_eof(&importer)) /* end of data */ + break; + } + + if (!GREEDY_REALLOC(iovec, n_allocated, n_iovec + importer.iovw.count + 2)) + return log_oom(); + + if (journal_importer_eof(&importer)) { + log_warning("Did not receive a full journal entry on stdin, ignoring message sent by reporter"); + + message = strjoin("MESSAGE=Process ", context[CONTEXT_PID], + " (", context[CONTEXT_COMM], ")" + " of user ", context[CONTEXT_UID], + " failed with ", context[CONTEXT_SIGNAL]); + if (!message) { + r = log_oom(); + goto finish; + } + iovec[n_iovec++] = IOVEC_MAKE_STRING(message); + } else { + for (i = 0; i < importer.iovw.count; i++) + iovec[n_iovec++] = importer.iovw.iovec[i]; + } + + iovec[n_iovec++] = IOVEC_MAKE_STRING("MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR); + assert_cc(2 == LOG_CRIT); + iovec[n_iovec++] = IOVEC_MAKE_STRING("PRIORITY=2"); + + assert(n_iovec <= n_allocated); + + r = sd_journal_sendv(iovec, n_iovec); + if (r < 0) + log_error_errno(r, "Failed to log backtrace: %m"); + + finish: + for (i = 0; i < n_to_free; i++) + free(iovec[i].iov_base); + + /* Those fields are allocated by gather_pid_metadata */ + free(context[CONTEXT_COMM]); + free(context[CONTEXT_EXE]); + free(context[CONTEXT_UNIT]); + + return r; +} + +static int run(int argc, char *argv[]) { + int r; + + /* First, log to a safe place, since we don't know what crashed and it might + * be journald which we'd rather not log to then. */ + + log_set_target(LOG_TARGET_KMSG); + log_open(); + + /* Make sure we never enter a loop */ + (void) prctl(PR_SET_DUMPABLE, 0); + + /* Ignore all parse errors */ + (void) parse_config(); + + log_debug("Selected storage '%s'.", coredump_storage_to_string(arg_storage)); + log_debug("Selected compression %s.", yes_no(arg_compress)); + + r = sd_listen_fds(false); + if (r < 0) + return log_error_errno(r, "Failed to determine the number of file descriptors: %m"); + + /* If we got an fd passed, we are running in coredumpd mode. Otherwise we + * are invoked from the kernel as coredump handler. */ + if (r == 0) { + if (streq_ptr(argv[1], "--backtrace")) + return process_backtrace(argc, argv); + else + return process_kernel(argc, argv); + } else if (r == 1) + return process_socket(SD_LISTEN_FDS_START); + + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Received unexpected number of file descriptors."); +} + +DEFINE_MAIN_FUNCTION(run); diff --git a/src/coredump/coredump.conf b/src/coredump/coredump.conf new file mode 100644 index 0000000..c2f0643 --- /dev/null +++ b/src/coredump/coredump.conf @@ -0,0 +1,21 @@ +# This file is part of systemd. +# +# systemd is free software; you can redistribute it and/or modify it +# under the terms of the GNU Lesser General Public License as published by +# the Free Software Foundation; either version 2.1 of the License, or +# (at your option) any later version. +# +# Entries in this file show the compile time defaults. +# You can change settings by editing this file. +# Defaults can be restored by simply deleting this file. +# +# See coredump.conf(5) for details. + +[Coredump] +#Storage=external +#Compress=yes +#ProcessSizeMax=2G +#ExternalSizeMax=2G +#JournalSizeMax=767M +#MaxUse= +#KeepFree= diff --git a/src/coredump/coredumpctl.c b/src/coredump/coredumpctl.c new file mode 100644 index 0000000..fbee242 --- /dev/null +++ b/src/coredump/coredumpctl.c @@ -0,0 +1,1096 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <fcntl.h> +#include <getopt.h> +#include <locale.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +#include "sd-bus.h" +#include "sd-journal.h" +#include "sd-messages.h" + +#include "alloc-util.h" +#include "bus-error.h" +#include "bus-util.h" +#include "compress.h" +#include "def.h" +#include "fd-util.h" +#include "fs-util.h" +#include "journal-internal.h" +#include "journal-util.h" +#include "log.h" +#include "macro.h" +#include "main-func.h" +#include "pager.h" +#include "parse-util.h" +#include "path-util.h" +#include "pretty-print.h" +#include "process-util.h" +#include "rlimit-util.h" +#include "sigbus.h" +#include "signal-util.h" +#include "string-util.h" +#include "strv.h" +#include "terminal-util.h" +#include "tmpfile-util.h" +#include "user-util.h" +#include "util.h" +#include "verbs.h" + +#define SHORT_BUS_CALL_TIMEOUT_USEC (3 * USEC_PER_SEC) + +static usec_t arg_since = USEC_INFINITY, arg_until = USEC_INFINITY; +static const char* arg_field = NULL; +static const char *arg_debugger = NULL; +static const char *arg_directory = NULL; +static PagerFlags arg_pager_flags = 0; +static int arg_no_legend = false; +static int arg_one = false; +static const char* arg_output = NULL; +static bool arg_reverse = false; +static bool arg_quiet = false; + +static int add_match(sd_journal *j, const char *match) { + _cleanup_free_ char *p = NULL; + const char* prefix, *pattern; + pid_t pid; + int r; + + if (strchr(match, '=')) + prefix = ""; + else if (strchr(match, '/')) { + r = path_make_absolute_cwd(match, &p); + if (r < 0) + return log_error_errno(r, "path_make_absolute_cwd(\"%s\"): %m", match); + + match = p; + prefix = "COREDUMP_EXE="; + } else if (parse_pid(match, &pid) >= 0) + prefix = "COREDUMP_PID="; + else + prefix = "COREDUMP_COMM="; + + pattern = strjoina(prefix, match); + log_debug("Adding match: %s", pattern); + r = sd_journal_add_match(j, pattern, 0); + if (r < 0) + return log_error_errno(r, "Failed to add match \"%s\": %m", match); + + return 0; +} + +static int add_matches(sd_journal *j, char **matches) { + char **match; + int r; + + r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR, 0); + if (r < 0) + return log_error_errno(r, "Failed to add match \"%s\": %m", "MESSAGE_ID=" SD_MESSAGE_COREDUMP_STR); + + r = sd_journal_add_match(j, "MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR, 0); + if (r < 0) + return log_error_errno(r, "Failed to add match \"%s\": %m", "MESSAGE_ID=" SD_MESSAGE_BACKTRACE_STR); + + STRV_FOREACH(match, matches) { + r = add_match(j, *match); + if (r < 0) + return r; + } + + return 0; +} + +static int acquire_journal(sd_journal **ret, char **matches) { + _cleanup_(sd_journal_closep) sd_journal *j = NULL; + int r; + + assert(ret); + + if (arg_directory) { + r = sd_journal_open_directory(&j, arg_directory, 0); + if (r < 0) + return log_error_errno(r, "Failed to open journals in directory: %s: %m", arg_directory); + } else { + r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); + if (r < 0) + return log_error_errno(r, "Failed to open journal: %m"); + } + + r = journal_access_check_and_warn(j, arg_quiet, true); + if (r < 0) + return r; + + r = add_matches(j, matches); + if (r < 0) + return r; + + if (DEBUG_LOGGING) { + _cleanup_free_ char *filter; + + filter = journal_make_match_string(j); + log_debug("Journal filter: %s", filter); + } + + *ret = TAKE_PTR(j); + + return 0; +} + +static int help(void) { + _cleanup_free_ char *link = NULL; + int r; + + r = terminal_urlify_man("coredumpctl", "1", &link); + if (r < 0) + return log_oom(); + + printf("%s [OPTIONS...]\n\n" + "List or retrieve coredumps from the journal.\n\n" + "Flags:\n" + " -h --help Show this help\n" + " --version Print version string\n" + " --no-pager Do not pipe output into a pager\n" + " --no-legend Do not print the column headers\n" + " --debugger=DEBUGGER Use the given debugger\n" + " -1 Show information about most recent entry only\n" + " -S --since=DATE Only print coredumps since the date\n" + " -U --until=DATE Only print coredumps until the date\n" + " -r --reverse Show the newest entries first\n" + " -F --field=FIELD List all values a certain field takes\n" + " -o --output=FILE Write output to FILE\n" + " -D --directory=DIR Use journal files from directory\n\n" + " -q --quiet Do not show info messages and privilege warning\n" + "Commands:\n" + " list [MATCHES...] List available coredumps (default)\n" + " info [MATCHES...] Show detailed information about one or more coredumps\n" + " dump [MATCHES...] Print first matching coredump to stdout\n" + " debug [MATCHES...] Start a debugger for the first matching coredump\n" + "\nSee the %s for details.\n" + , program_invocation_short_name + , link + ); + + return 0; +} + +static int parse_argv(int argc, char *argv[]) { + enum { + ARG_VERSION = 0x100, + ARG_NO_PAGER, + ARG_NO_LEGEND, + ARG_DEBUGGER, + }; + + int c, r; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version" , no_argument, NULL, ARG_VERSION }, + { "no-pager", no_argument, NULL, ARG_NO_PAGER }, + { "no-legend", no_argument, NULL, ARG_NO_LEGEND }, + { "debugger", required_argument, NULL, ARG_DEBUGGER }, + { "output", required_argument, NULL, 'o' }, + { "field", required_argument, NULL, 'F' }, + { "directory", required_argument, NULL, 'D' }, + { "reverse", no_argument, NULL, 'r' }, + { "since", required_argument, NULL, 'S' }, + { "until", required_argument, NULL, 'U' }, + { "quiet", no_argument, NULL, 'q' }, + {} + }; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "ho:F:1D:rS:U:q", options, NULL)) >= 0) + switch(c) { + case 'h': + return help(); + + case ARG_VERSION: + return version(); + + case ARG_NO_PAGER: + arg_pager_flags |= PAGER_DISABLE; + break; + + case ARG_NO_LEGEND: + arg_no_legend = true; + break; + + case ARG_DEBUGGER: + arg_debugger = optarg; + break; + + case 'o': + if (arg_output) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Cannot set output more than once."); + + arg_output = optarg; + break; + + case 'S': + r = parse_timestamp(optarg, &arg_since); + if (r < 0) + return log_error_errno(r, "Failed to parse timestamp '%s': %m", optarg); + break; + + case 'U': + r = parse_timestamp(optarg, &arg_until); + if (r < 0) + return log_error_errno(r, "Failed to parse timestamp '%s': %m", optarg); + break; + + case 'F': + if (arg_field) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Cannot use --field/-F more than once."); + arg_field = optarg; + break; + + case '1': + arg_one = true; + break; + + case 'D': + arg_directory = optarg; + break; + + case 'r': + arg_reverse = true; + break; + + case 'q': + arg_quiet = true; + break; + + case '?': + return -EINVAL; + + default: + assert_not_reached("Unhandled option"); + } + + if (arg_since != USEC_INFINITY && arg_until != USEC_INFINITY && + arg_since > arg_until) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "--since= must be before --until=."); + + return 1; +} + +static int retrieve(const void *data, + size_t len, + const char *name, + char **var) { + + size_t ident; + char *v; + + ident = strlen(name) + 1; /* name + "=" */ + + if (len < ident) + return 0; + + if (memcmp(data, name, ident - 1) != 0) + return 0; + + if (((const char*) data)[ident - 1] != '=') + return 0; + + v = strndup((const char*)data + ident, len - ident); + if (!v) + return log_oom(); + + free(*var); + *var = v; + + return 1; +} + +static int print_field(FILE* file, sd_journal *j) { + const void *d; + size_t l; + + assert(file); + assert(j); + + assert(arg_field); + + /* A (user-specified) field may appear more than once for a given entry. + * We will print all of the occurences. + * This is different below for fields that systemd-coredump uses, + * because they cannot meaningfully appear more than once. + */ + SD_JOURNAL_FOREACH_DATA(j, d, l) { + _cleanup_free_ char *value = NULL; + int r; + + r = retrieve(d, l, arg_field, &value); + if (r < 0) + return r; + if (r > 0) + fprintf(file, "%s\n", value); + } + + return 0; +} + +#define RETRIEVE(d, l, name, arg) \ + { \ + int _r = retrieve(d, l, name, &arg); \ + if (_r < 0) \ + return _r; \ + if (_r > 0) \ + continue; \ + } + +static int print_list(FILE* file, sd_journal *j, int had_legend) { + _cleanup_free_ char + *mid = NULL, *pid = NULL, *uid = NULL, *gid = NULL, + *sgnl = NULL, *exe = NULL, *comm = NULL, *cmdline = NULL, + *filename = NULL, *truncated = NULL, *coredump = NULL; + const void *d; + size_t l; + usec_t t; + char buf[FORMAT_TIMESTAMP_MAX]; + int r; + const char *present; + bool normal_coredump; + + assert(file); + assert(j); + + SD_JOURNAL_FOREACH_DATA(j, d, l) { + RETRIEVE(d, l, "MESSAGE_ID", mid); + RETRIEVE(d, l, "COREDUMP_PID", pid); + RETRIEVE(d, l, "COREDUMP_UID", uid); + RETRIEVE(d, l, "COREDUMP_GID", gid); + RETRIEVE(d, l, "COREDUMP_SIGNAL", sgnl); + RETRIEVE(d, l, "COREDUMP_EXE", exe); + RETRIEVE(d, l, "COREDUMP_COMM", comm); + RETRIEVE(d, l, "COREDUMP_CMDLINE", cmdline); + RETRIEVE(d, l, "COREDUMP_FILENAME", filename); + RETRIEVE(d, l, "COREDUMP_TRUNCATED", truncated); + RETRIEVE(d, l, "COREDUMP", coredump); + } + + if (!pid && !uid && !gid && !sgnl && !exe && !comm && !cmdline && !filename) { + log_warning("Empty coredump log entry"); + return -EINVAL; + } + + r = sd_journal_get_realtime_usec(j, &t); + if (r < 0) + return log_error_errno(r, "Failed to get realtime timestamp: %m"); + + format_timestamp(buf, sizeof(buf), t); + + if (!had_legend && !arg_no_legend) + fprintf(file, "%-*s %*s %*s %*s %*s %-*s %s\n", + FORMAT_TIMESTAMP_WIDTH, "TIME", + 6, "PID", + 5, "UID", + 5, "GID", + 3, "SIG", + 9, "COREFILE", + "EXE"); + + normal_coredump = streq_ptr(mid, SD_MESSAGE_COREDUMP_STR); + + if (filename) + if (access(filename, R_OK) == 0) + present = "present"; + else if (errno == ENOENT) + present = "missing"; + else + present = "error"; + else if (coredump) + present = "journal"; + else if (normal_coredump) + present = "none"; + else + present = "-"; + + if (STR_IN_SET(present, "present", "journal") && truncated && parse_boolean(truncated) > 0) + present = "truncated"; + + fprintf(file, "%-*s %*s %*s %*s %*s %-*s %s\n", + FORMAT_TIMESTAMP_WIDTH, buf, + 6, strna(pid), + 5, strna(uid), + 5, strna(gid), + 3, normal_coredump ? strna(sgnl) : "-", + 9, present, + strna(exe ?: (comm ?: cmdline))); + + return 0; +} + +static int print_info(FILE *file, sd_journal *j, bool need_space) { + _cleanup_free_ char + *mid = NULL, *pid = NULL, *uid = NULL, *gid = NULL, + *sgnl = NULL, *exe = NULL, *comm = NULL, *cmdline = NULL, + *unit = NULL, *user_unit = NULL, *session = NULL, + *boot_id = NULL, *machine_id = NULL, *hostname = NULL, + *slice = NULL, *cgroup = NULL, *owner_uid = NULL, + *message = NULL, *timestamp = NULL, *filename = NULL, + *truncated = NULL, *coredump = NULL; + const void *d; + size_t l; + bool normal_coredump; + int r; + + assert(file); + assert(j); + + SD_JOURNAL_FOREACH_DATA(j, d, l) { + RETRIEVE(d, l, "MESSAGE_ID", mid); + RETRIEVE(d, l, "COREDUMP_PID", pid); + RETRIEVE(d, l, "COREDUMP_UID", uid); + RETRIEVE(d, l, "COREDUMP_GID", gid); + RETRIEVE(d, l, "COREDUMP_SIGNAL", sgnl); + RETRIEVE(d, l, "COREDUMP_EXE", exe); + RETRIEVE(d, l, "COREDUMP_COMM", comm); + RETRIEVE(d, l, "COREDUMP_CMDLINE", cmdline); + RETRIEVE(d, l, "COREDUMP_UNIT", unit); + RETRIEVE(d, l, "COREDUMP_USER_UNIT", user_unit); + RETRIEVE(d, l, "COREDUMP_SESSION", session); + RETRIEVE(d, l, "COREDUMP_OWNER_UID", owner_uid); + RETRIEVE(d, l, "COREDUMP_SLICE", slice); + RETRIEVE(d, l, "COREDUMP_CGROUP", cgroup); + RETRIEVE(d, l, "COREDUMP_TIMESTAMP", timestamp); + RETRIEVE(d, l, "COREDUMP_FILENAME", filename); + RETRIEVE(d, l, "COREDUMP_TRUNCATED", truncated); + RETRIEVE(d, l, "COREDUMP", coredump); + RETRIEVE(d, l, "_BOOT_ID", boot_id); + RETRIEVE(d, l, "_MACHINE_ID", machine_id); + RETRIEVE(d, l, "_HOSTNAME", hostname); + RETRIEVE(d, l, "MESSAGE", message); + } + + if (need_space) + fputs("\n", file); + + normal_coredump = streq_ptr(mid, SD_MESSAGE_COREDUMP_STR); + + if (comm) + fprintf(file, + " PID: %s%s%s (%s)\n", + ansi_highlight(), strna(pid), ansi_normal(), comm); + else + fprintf(file, + " PID: %s%s%s\n", + ansi_highlight(), strna(pid), ansi_normal()); + + if (uid) { + uid_t n; + + if (parse_uid(uid, &n) >= 0) { + _cleanup_free_ char *u = NULL; + + u = uid_to_name(n); + fprintf(file, + " UID: %s (%s)\n", + uid, u); + } else { + fprintf(file, + " UID: %s\n", + uid); + } + } + + if (gid) { + gid_t n; + + if (parse_gid(gid, &n) >= 0) { + _cleanup_free_ char *g = NULL; + + g = gid_to_name(n); + fprintf(file, + " GID: %s (%s)\n", + gid, g); + } else { + fprintf(file, + " GID: %s\n", + gid); + } + } + + if (sgnl) { + int sig; + const char *name = normal_coredump ? "Signal" : "Reason"; + + if (normal_coredump && safe_atoi(sgnl, &sig) >= 0) + fprintf(file, " %s: %s (%s)\n", name, sgnl, signal_to_string(sig)); + else + fprintf(file, " %s: %s\n", name, sgnl); + } + + if (timestamp) { + usec_t u; + + r = safe_atou64(timestamp, &u); + if (r >= 0) { + char absolute[FORMAT_TIMESTAMP_MAX], relative[FORMAT_TIMESPAN_MAX]; + + fprintf(file, + " Timestamp: %s (%s)\n", + format_timestamp(absolute, sizeof(absolute), u), + format_timestamp_relative(relative, sizeof(relative), u)); + + } else + fprintf(file, " Timestamp: %s\n", timestamp); + } + + if (cmdline) + fprintf(file, " Command Line: %s\n", cmdline); + if (exe) + fprintf(file, " Executable: %s%s%s\n", ansi_highlight(), exe, ansi_normal()); + if (cgroup) + fprintf(file, " Control Group: %s\n", cgroup); + if (unit) + fprintf(file, " Unit: %s\n", unit); + if (user_unit) + fprintf(file, " User Unit: %s\n", user_unit); + if (slice) + fprintf(file, " Slice: %s\n", slice); + if (session) + fprintf(file, " Session: %s\n", session); + if (owner_uid) { + uid_t n; + + if (parse_uid(owner_uid, &n) >= 0) { + _cleanup_free_ char *u = NULL; + + u = uid_to_name(n); + fprintf(file, + " Owner UID: %s (%s)\n", + owner_uid, u); + } else { + fprintf(file, + " Owner UID: %s\n", + owner_uid); + } + } + if (boot_id) + fprintf(file, " Boot ID: %s\n", boot_id); + if (machine_id) + fprintf(file, " Machine ID: %s\n", machine_id); + if (hostname) + fprintf(file, " Hostname: %s\n", hostname); + + if (filename) { + bool inacc, trunc; + + inacc = access(filename, R_OK) < 0; + trunc = truncated && parse_boolean(truncated) > 0; + + if (inacc || trunc) + fprintf(file, " Storage: %s%s (%s%s%s)%s\n", + ansi_highlight_red(), + filename, + inacc ? "inaccessible" : "", + inacc && trunc ? ", " : "", + trunc ? "truncated" : "", + ansi_normal()); + else + fprintf(file, " Storage: %s\n", filename); + } + + else if (coredump) + fprintf(file, " Storage: journal\n"); + else + fprintf(file, " Storage: none\n"); + + if (message) { + _cleanup_free_ char *m = NULL; + + m = strreplace(message, "\n", "\n "); + + fprintf(file, " Message: %s\n", strstrip(m ?: message)); + } + + return 0; +} + +static int focus(sd_journal *j) { + int r; + + r = sd_journal_seek_tail(j); + if (r == 0) + r = sd_journal_previous(j); + if (r < 0) + return log_error_errno(r, "Failed to search journal: %m"); + if (r == 0) + return log_error_errno(SYNTHETIC_ERRNO(ESRCH), + "No match found."); + return r; +} + +static int print_entry(sd_journal *j, unsigned n_found, bool verb_is_info) { + assert(j); + + if (verb_is_info) + return print_info(stdout, j, n_found); + else if (arg_field) + return print_field(stdout, j); + else + return print_list(stdout, j, n_found); +} + +static int dump_list(int argc, char **argv, void *userdata) { + _cleanup_(sd_journal_closep) sd_journal *j = NULL; + unsigned n_found = 0; + bool verb_is_info; + int r; + + verb_is_info = (argc >= 1 && streq(argv[0], "info")); + + r = acquire_journal(&j, argv + 1); + if (r < 0) + return r; + + (void) pager_open(arg_pager_flags); + + /* The coredumps are likely to compressed, and for just + * listing them we don't need to decompress them, so let's + * pick a fairly low data threshold here */ + sd_journal_set_data_threshold(j, 4096); + + /* "info" without pattern implies "-1" */ + if (arg_one || (verb_is_info && argc == 1)) { + r = focus(j); + if (r < 0) + return r; + + return print_entry(j, 0, verb_is_info); + } else { + if (arg_since != USEC_INFINITY && !arg_reverse) + r = sd_journal_seek_realtime_usec(j, arg_since); + else if (arg_until != USEC_INFINITY && arg_reverse) + r = sd_journal_seek_realtime_usec(j, arg_until); + else if (arg_reverse) + r = sd_journal_seek_tail(j); + else + r = sd_journal_seek_head(j); + if (r < 0) + return log_error_errno(r, "Failed to seek to date: %m"); + + for (;;) { + if (!arg_reverse) + r = sd_journal_next(j); + else + r = sd_journal_previous(j); + + if (r < 0) + return log_error_errno(r, "Failed to iterate through journal: %m"); + + if (r == 0) + break; + + if (arg_until != USEC_INFINITY && !arg_reverse) { + usec_t usec; + + r = sd_journal_get_realtime_usec(j, &usec); + if (r < 0) + return log_error_errno(r, "Failed to determine timestamp: %m"); + if (usec > arg_until) + continue; + } + + if (arg_since != USEC_INFINITY && arg_reverse) { + usec_t usec; + + r = sd_journal_get_realtime_usec(j, &usec); + if (r < 0) + return log_error_errno(r, "Failed to determine timestamp: %m"); + if (usec < arg_since) + continue; + } + + r = print_entry(j, n_found++, verb_is_info); + if (r < 0) + return r; + } + + if (!arg_field && n_found <= 0) { + if (!arg_quiet) + log_notice("No coredumps found."); + return -ESRCH; + } + } + + return 0; +} + +static int save_core(sd_journal *j, FILE *file, char **path, bool *unlink_temp) { + const char *data; + _cleanup_free_ char *filename = NULL; + size_t len; + int r, fd; + _cleanup_close_ int fdt = -1; + char *temp = NULL; + + assert(!(file && path)); /* At most one can be specified */ + assert(!!path == !!unlink_temp); /* Those must be specified together */ + + /* Look for a coredump on disk first. */ + r = sd_journal_get_data(j, "COREDUMP_FILENAME", (const void**) &data, &len); + if (r == 0) + retrieve(data, len, "COREDUMP_FILENAME", &filename); + else { + if (r != -ENOENT) + return log_error_errno(r, "Failed to retrieve COREDUMP_FILENAME field: %m"); + /* Check that we can have a COREDUMP field. We still haven't set a high + * data threshold, so we'll get a few kilobytes at most. + */ + + r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len); + if (r == -ENOENT) + return log_error_errno(r, "Coredump entry has no core attached (neither internally in the journal nor externally on disk)."); + if (r < 0) + return log_error_errno(r, "Failed to retrieve COREDUMP field: %m"); + } + + if (filename) { + if (access(filename, R_OK) < 0) + return log_error_errno(errno, "File \"%s\" is not readable: %m", filename); + + if (path && !endswith(filename, ".xz") && !endswith(filename, ".lz4")) { + *path = TAKE_PTR(filename); + + return 0; + } + } + + if (path) { + const char *vt; + + /* Create a temporary file to write the uncompressed core to. */ + + r = var_tmp_dir(&vt); + if (r < 0) + return log_error_errno(r, "Failed to acquire temporary directory path: %m"); + + temp = strjoin(vt, "/coredump-XXXXXX"); + if (!temp) + return log_oom(); + + fdt = mkostemp_safe(temp); + if (fdt < 0) + return log_error_errno(fdt, "Failed to create temporary file: %m"); + log_debug("Created temporary file %s", temp); + + fd = fdt; + } else { + /* If neither path or file are specified, we will write to stdout. Let's now check + * if stdout is connected to a tty. We checked that the file exists, or that the + * core might be stored in the journal. In this second case, if we found the entry, + * in all likelyhood we will be able to access the COREDUMP= field. In either case, + * we stop before doing any "real" work, i.e. before starting decompression or + * reading from the file or creating temporary files. + */ + if (!file) { + if (on_tty()) + return log_error_errno(SYNTHETIC_ERRNO(ENOTTY), + "Refusing to dump core to tty" + " (use shell redirection or specify --output)."); + file = stdout; + } + + fd = fileno(file); + } + + if (filename) { +#if HAVE_XZ || HAVE_LZ4 + _cleanup_close_ int fdf; + + fdf = open(filename, O_RDONLY | O_CLOEXEC); + if (fdf < 0) { + r = log_error_errno(errno, "Failed to open %s: %m", filename); + goto error; + } + + r = decompress_stream(filename, fdf, fd, -1); + if (r < 0) { + log_error_errno(r, "Failed to decompress %s: %m", filename); + goto error; + } +#else + log_error("Cannot decompress file. Compiled without compression support."); + r = -EOPNOTSUPP; + goto error; +#endif + } else { + ssize_t sz; + + /* We want full data, nothing truncated. */ + sd_journal_set_data_threshold(j, 0); + + r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len); + if (r < 0) + return log_error_errno(r, "Failed to retrieve COREDUMP field: %m"); + + assert(len >= 9); + data += 9; + len -= 9; + + sz = write(fd, data, len); + if (sz < 0) { + r = log_error_errno(errno, "Failed to write output: %m"); + goto error; + } + if (sz != (ssize_t) len) { + log_error("Short write to output."); + r = -EIO; + goto error; + } + } + + if (temp) { + *path = temp; + *unlink_temp = true; + } + return 0; + +error: + if (temp) { + unlink(temp); + log_debug("Removed temporary file %s", temp); + } + return r; +} + +static int dump_core(int argc, char **argv, void *userdata) { + _cleanup_(sd_journal_closep) sd_journal *j = NULL; + _cleanup_fclose_ FILE *f = NULL; + int r; + + if (arg_field) { + log_error("Option --field/-F only makes sense with list"); + return -EINVAL; + } + + r = acquire_journal(&j, argv + 1); + if (r < 0) + return r; + + r = focus(j); + if (r < 0) + return r; + + if (arg_output) { + f = fopen(arg_output, "we"); + if (!f) + return log_error_errno(errno, "Failed to open \"%s\" for writing: %m", arg_output); + } + + print_info(f ? stdout : stderr, j, false); + + r = save_core(j, f, NULL, NULL); + if (r < 0) + return r; + + r = sd_journal_previous(j); + if (r > 0 && !arg_quiet) + log_notice("More than one entry matches, ignoring rest."); + + return 0; +} + +static int run_debug(int argc, char **argv, void *userdata) { + _cleanup_(sd_journal_closep) sd_journal *j = NULL; + _cleanup_free_ char *exe = NULL, *path = NULL; + bool unlink_path = false; + const char *data, *fork_name; + size_t len; + pid_t pid; + int r; + + if (!arg_debugger) { + char *env_debugger; + + env_debugger = getenv("SYSTEMD_DEBUGGER"); + if (env_debugger) + arg_debugger = env_debugger; + else + arg_debugger = "gdb"; + } + + if (arg_field) { + log_error("Option --field/-F only makes sense with list"); + return -EINVAL; + } + + r = acquire_journal(&j, argv + 1); + if (r < 0) + return r; + + r = focus(j); + if (r < 0) + return r; + + print_info(stdout, j, false); + fputs("\n", stdout); + + r = sd_journal_get_data(j, "COREDUMP_EXE", (const void**) &data, &len); + if (r < 0) + return log_error_errno(r, "Failed to retrieve COREDUMP_EXE field: %m"); + + assert(len > STRLEN("COREDUMP_EXE=")); + data += STRLEN("COREDUMP_EXE="); + len -= STRLEN("COREDUMP_EXE="); + + exe = strndup(data, len); + if (!exe) + return log_oom(); + + if (endswith(exe, " (deleted)")) { + log_error("Binary already deleted."); + return -ENOENT; + } + + if (!path_is_absolute(exe)) { + log_error("Binary is not an absolute path."); + return -ENOENT; + } + + r = save_core(j, NULL, &path, &unlink_path); + if (r < 0) + return r; + + /* Don't interfere with gdb and its handling of SIGINT. */ + (void) ignore_signals(SIGINT, -1); + + fork_name = strjoina("(", arg_debugger, ")"); + + r = safe_fork(fork_name, FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid); + if (r < 0) + goto finish; + if (r == 0) { + execlp(arg_debugger, arg_debugger, exe, "-c", path, NULL); + log_open(); + log_error_errno(errno, "Failed to invoke %s: %m", arg_debugger); + _exit(EXIT_FAILURE); + } + + r = wait_for_terminate_and_check(arg_debugger, pid, WAIT_LOG_ABNORMAL); + +finish: + (void) default_signals(SIGINT, -1); + + if (unlink_path) { + log_debug("Removed temporary file %s", path); + unlink(path); + } + + return r; +} + +static int check_units_active(void) { + _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; + _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL; + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL; + int c = 0, r; + const char *id, *state, *substate; + + if (arg_quiet) + return false; + + r = sd_bus_default_system(&bus); + if (r < 0) + return log_error_errno(r, "Failed to acquire bus: %m"); + + r = sd_bus_message_new_method_call( + bus, + &m, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "ListUnitsByPatterns"); + if (r < 0) + return bus_log_create_error(r); + + r = sd_bus_message_append_strv(m, NULL); + if (r < 0) + return bus_log_create_error(r); + + r = sd_bus_message_append_strv(m, STRV_MAKE("systemd-coredump@*.service")); + if (r < 0) + return bus_log_create_error(r); + + r = sd_bus_call(bus, m, SHORT_BUS_CALL_TIMEOUT_USEC, &error, &reply); + if (r < 0) + return log_error_errno(r, "Failed to check if any systemd-coredump@.service units are running: %s", + bus_error_message(&error, r)); + + r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssssouso)"); + if (r < 0) + return bus_log_parse_error(r); + + while ((r = sd_bus_message_read( + reply, "(ssssssouso)", + &id, NULL, NULL, &state, &substate, + NULL, NULL, NULL, NULL, NULL)) > 0) { + bool found = !STR_IN_SET(state, "inactive", "dead", "failed"); + log_debug("Unit %s is %s/%s, %scounting it.", id, state, substate, found ? "" : "not "); + c += found; + } + if (r < 0) + return bus_log_parse_error(r); + + r = sd_bus_message_exit_container(reply); + if (r < 0) + return bus_log_parse_error(r); + + return c; +} + +static int coredumpctl_main(int argc, char *argv[]) { + + static const Verb verbs[] = { + { "list", VERB_ANY, VERB_ANY, VERB_DEFAULT, dump_list }, + { "info", VERB_ANY, VERB_ANY, 0, dump_list }, + { "dump", VERB_ANY, VERB_ANY, 0, dump_core }, + { "debug", VERB_ANY, VERB_ANY, 0, run_debug }, + { "gdb", VERB_ANY, VERB_ANY, 0, run_debug }, + {} + }; + + return dispatch_verb(argc, argv, verbs, NULL); +} + +static int run(int argc, char *argv[]) { + int r, units_active; + + setlocale(LC_ALL, ""); + log_parse_environment(); + log_open(); + + /* The journal merging logic potentially needs a lot of fds. */ + (void) rlimit_nofile_bump(HIGH_RLIMIT_NOFILE); + + r = parse_argv(argc, argv); + if (r <= 0) + return r; + + sigbus_install(); + + units_active = check_units_active(); /* error is treated the same as 0 */ + + r = coredumpctl_main(argc, argv); + + if (units_active > 0) + printf("%s-- Notice: %d systemd-coredump@.service %s, output may be incomplete.%s\n", + ansi_highlight_red(), + units_active, units_active == 1 ? "unit is running" : "units are running", + ansi_normal()); + return r; +} + +DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run); diff --git a/src/coredump/meson.build b/src/coredump/meson.build new file mode 100644 index 0000000..7fa5942 --- /dev/null +++ b/src/coredump/meson.build @@ -0,0 +1,28 @@ +# SPDX-License-Identifier: LGPL-2.1+ + +systemd_coredump_sources = files(''' + coredump.c + coredump-vacuum.c + coredump-vacuum.h +'''.split()) + +if conf.get('HAVE_ELFUTILS') == 1 + systemd_coredump_sources += files(['stacktrace.c', + 'stacktrace.h']) +endif + +coredumpctl_sources = files('coredumpctl.c') + +if conf.get('ENABLE_COREDUMP') == 1 + install_data('coredump.conf', + install_dir : pkgsysconfdir) +endif + +tests += [ + [['src/coredump/test-coredump-vacuum.c', + 'src/coredump/coredump-vacuum.c', + 'src/coredump/coredump-vacuum.h'], + [], + [], + 'ENABLE_COREDUMP', 'manual'], +] diff --git a/src/coredump/stacktrace.c b/src/coredump/stacktrace.c new file mode 100644 index 0000000..dab4c1a --- /dev/null +++ b/src/coredump/stacktrace.c @@ -0,0 +1,185 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <dwarf.h> +#include <elfutils/libdwfl.h> +#include <stdio_ext.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "format-util.h" +#include "macro.h" +#include "stacktrace.h" +#include "string-util.h" +#include "util.h" + +#define FRAMES_MAX 64 +#define THREADS_MAX 64 + +struct stack_context { + FILE *f; + Dwfl *dwfl; + Elf *elf; + unsigned n_thread; + unsigned n_frame; +}; + +static int frame_callback(Dwfl_Frame *frame, void *userdata) { + struct stack_context *c = userdata; + Dwarf_Addr pc, pc_adjusted, bias = 0; + _cleanup_free_ Dwarf_Die *scopes = NULL; + const char *fname = NULL, *symbol = NULL; + Dwfl_Module *module; + bool is_activation; + + assert(frame); + assert(c); + + if (c->n_frame >= FRAMES_MAX) + return DWARF_CB_ABORT; + + if (!dwfl_frame_pc(frame, &pc, &is_activation)) + return DWARF_CB_ABORT; + + pc_adjusted = pc - (is_activation ? 0 : 1); + + module = dwfl_addrmodule(c->dwfl, pc_adjusted); + if (module) { + Dwarf_Die *s, *cudie; + int n; + + cudie = dwfl_module_addrdie(module, pc_adjusted, &bias); + if (cudie) { + n = dwarf_getscopes(cudie, pc_adjusted - bias, &scopes); + for (s = scopes; s < scopes + n; s++) { + if (IN_SET(dwarf_tag(s), DW_TAG_subprogram, DW_TAG_inlined_subroutine, DW_TAG_entry_point)) { + Dwarf_Attribute *a, space; + + a = dwarf_attr_integrate(s, DW_AT_MIPS_linkage_name, &space); + if (!a) + a = dwarf_attr_integrate(s, DW_AT_linkage_name, &space); + if (a) + symbol = dwarf_formstring(a); + if (!symbol) + symbol = dwarf_diename(s); + + if (symbol) + break; + } + } + } + + if (!symbol) + symbol = dwfl_module_addrname(module, pc_adjusted); + + fname = dwfl_module_info(module, NULL, NULL, NULL, NULL, NULL, NULL, NULL); + } + + fprintf(c->f, "#%-2u 0x%016" PRIx64 " %s (%s)\n", c->n_frame, (uint64_t) pc, strna(symbol), strna(fname)); + c->n_frame++; + + return DWARF_CB_OK; +} + +static int thread_callback(Dwfl_Thread *thread, void *userdata) { + struct stack_context *c = userdata; + pid_t tid; + + assert(thread); + assert(c); + + if (c->n_thread >= THREADS_MAX) + return DWARF_CB_ABORT; + + if (c->n_thread != 0) + fputc('\n', c->f); + + c->n_frame = 0; + + tid = dwfl_thread_tid(thread); + fprintf(c->f, "Stack trace of thread " PID_FMT ":\n", tid); + + if (dwfl_thread_getframes(thread, frame_callback, c) < 0) + return DWARF_CB_ABORT; + + c->n_thread++; + + return DWARF_CB_OK; +} + +int coredump_make_stack_trace(int fd, const char *executable, char **ret) { + + static const Dwfl_Callbacks callbacks = { + .find_elf = dwfl_build_id_find_elf, + .find_debuginfo = dwfl_standard_find_debuginfo, + }; + + struct stack_context c = {}; + char *buf = NULL; + size_t sz = 0; + int r; + + assert(fd >= 0); + assert(ret); + + if (lseek(fd, 0, SEEK_SET) == (off_t) -1) + return -errno; + + c.f = open_memstream(&buf, &sz); + if (!c.f) + return -ENOMEM; + + (void) __fsetlocking(c.f, FSETLOCKING_BYCALLER); + + elf_version(EV_CURRENT); + + c.elf = elf_begin(fd, ELF_C_READ_MMAP, NULL); + if (!c.elf) { + r = -EINVAL; + goto finish; + } + + c.dwfl = dwfl_begin(&callbacks); + if (!c.dwfl) { + r = -EINVAL; + goto finish; + } + + if (dwfl_core_file_report(c.dwfl, c.elf, executable) < 0) { + r = -EINVAL; + goto finish; + } + + if (dwfl_report_end(c.dwfl, NULL, NULL) != 0) { + r = -EINVAL; + goto finish; + } + + if (dwfl_core_file_attach(c.dwfl, c.elf) < 0) { + r = -EINVAL; + goto finish; + } + + if (dwfl_getthreads(c.dwfl, thread_callback, &c) < 0) { + r = -EINVAL; + goto finish; + } + + c.f = safe_fclose(c.f); + + *ret = TAKE_PTR(buf); + + r = 0; + +finish: + if (c.dwfl) + dwfl_end(c.dwfl); + + if (c.elf) + elf_end(c.elf); + + safe_fclose(c.f); + + free(buf); + + return r; +} diff --git a/src/coredump/stacktrace.h b/src/coredump/stacktrace.h new file mode 100644 index 0000000..5290042 --- /dev/null +++ b/src/coredump/stacktrace.h @@ -0,0 +1,4 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +int coredump_make_stack_trace(int fd, const char *executable, char **ret); diff --git a/src/coredump/test-coredump-vacuum.c b/src/coredump/test-coredump-vacuum.c new file mode 100644 index 0000000..75fb442 --- /dev/null +++ b/src/coredump/test-coredump-vacuum.c @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <stdlib.h> + +#include "coredump-vacuum.h" + +int main(int argc, char *argv[]) { + + if (coredump_vacuum(-1, (uint64_t) -1, 70 * 1024) < 0) + return EXIT_FAILURE; + + return EXIT_SUCCESS; +} |