diff options
Diffstat (limited to 'src/coredump/coredump.c')
| -rw-r--r-- | src/coredump/coredump.c | 119 |
1 files changed, 113 insertions, 6 deletions
diff --git a/src/coredump/coredump.c b/src/coredump/coredump.c index dcc09fcc6d..be724aed4e 100644 --- a/src/coredump/coredump.c +++ b/src/coredump/coredump.c @@ -327,9 +327,11 @@ static int save_external_coredump( r = safe_atou64(context[CONTEXT_RLIMIT], &rlimit); if (r < 0) return log_error_errno(r, "Failed to parse resource limit: %s", context[CONTEXT_RLIMIT]); - if (rlimit <= 0) { - /* Is coredumping disabled? Then don't bother saving/processing the coredump */ - log_info("Core Dumping has been disabled for process %s (%s).", context[CONTEXT_PID], context[CONTEXT_COMM]); + 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. */ + log_info("Core dumping has been disabled for process %s (%s).", context[CONTEXT_PID], context[CONTEXT_COMM]); return -EBADSLT; } @@ -558,6 +560,89 @@ static int compose_open_fds(pid_t pid, char **open_fds) { 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; + + while (1) { + 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; + + return get_process_cmdline(container_pid, 0, false, cmdline); +} + static int change_uid_gid(const char *context[]) { uid_t uid; gid_t gid; @@ -933,11 +1018,13 @@ static int process_kernel(int argc, char* argv[]) { /* The larger ones we allocate on the heap */ _cleanup_free_ char *core_owner_uid = NULL, *core_open_fds = NULL, *core_proc_status = NULL, - *core_proc_maps = NULL, *core_proc_limits = NULL, *core_proc_cgroup = NULL, *core_environ = NULL; + *core_proc_maps = NULL, *core_proc_limits = NULL, *core_proc_cgroup = NULL, *core_environ = NULL, + *core_proc_mountinfo = NULL, *core_container_cmdline = NULL; _cleanup_free_ char *exe = NULL, *comm = NULL; const char *context[_CONTEXT_MAX]; - struct iovec iovec[25]; + bool proc_self_root_is_slash; + struct iovec iovec[27]; size_t n_iovec = 0; uid_t owner_uid; const char *p; @@ -1110,6 +1197,15 @@ static int process_kernel(int argc, char* argv[]) { IOVEC_SET_STRING(iovec[n_iovec++], core_proc_cgroup); } + p = procfs_file_alloca(pid, "mountinfo"); + if (read_full_file(p, &t, NULL) >=0) { + core_proc_mountinfo = strappend("COREDUMP_PROC_MOUNTINFO=", t); + free(t); + + if (core_proc_mountinfo) + IOVEC_SET_STRING(iovec[n_iovec++], core_proc_mountinfo); + } + if (get_process_cwd(pid, &t) >= 0) { core_cwd = strjoina("COREDUMP_CWD=", t); free(t); @@ -1119,9 +1215,20 @@ static int process_kernel(int argc, char* argv[]) { if (get_process_root(pid, &t) >= 0) { core_root = strjoina("COREDUMP_ROOT=", t); - free(t); IOVEC_SET_STRING(iovec[n_iovec++], core_root); + + /* If the process' root is "/", then there is a chance it has + * mounted own root and hence being containerized. */ + proc_self_root_is_slash = strcmp(t, "/") == 0; + free(t); + if (proc_self_root_is_slash && get_process_container_parent_cmdline(pid, &t) > 0) { + core_container_cmdline = strappend("COREDUMP_CONTAINER_CMDLINE=", t); + free(t); + + if (core_container_cmdline) + IOVEC_SET_STRING(iovec[n_iovec++], core_container_cmdline); + } } if (get_process_environ(pid, &t) >= 0) { |