From: Eelco Dolstra Date: Thu, 21 Jun 2012 20:40:47 +0000 (-0400) Subject: journal: set the _SYSTEMD_UNIT field for messages from terminated processes X-Git-Tag: v186~125 X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=62bca2c657bf95fd1f69935eef09915afa5c69d9 journal: set the _SYSTEMD_UNIT field for messages from terminated processes As described in https://bugs.freedesktop.org/show_bug.cgi?id=50184 the journal currently doesn't set fields such as _SYSTEMD_UNIT properly for messages coming from processes that have already terminated. This means among other things that "systemctl status" may not show some of the output of services that wrote messages just before they exited. This patch fixes this by having processes that log to the journal write their unit identifier to journald when the connection to /run/systemd/journal/stdout is opened. Journald stores the unit ID and uses it to fill in _SYSTEMD_UNIT when it cannot be obtained normally (i.e. from the cgroup). To prevent impersonating another unit, this information is only used when the caller is root. This doesn't fix the general problem of getting metadata about messages from terminated processes (which requires some kernel support), but it allows "systemctl status" and similar queries to do the Right Thing for units that log via stdout/stderr. --- diff --git a/src/core/execute.c b/src/core/execute.c index bbc430e05..01dceb078 100644 --- a/src/core/execute.c +++ b/src/core/execute.c @@ -176,7 +176,7 @@ static int open_null_as(int flags, int nfd) { return r; } -static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, int nfd) { +static int connect_logger_as(const ExecContext *context, ExecOutput output, const char *ident, const char *unit_id, int nfd) { int fd, r; union sockaddr_union sa; @@ -205,6 +205,7 @@ static int connect_logger_as(const ExecContext *context, ExecOutput output, cons } dprintf(fd, + "%s\n" "%s\n" "%i\n" "%i\n" @@ -212,6 +213,7 @@ static int connect_logger_as(const ExecContext *context, ExecOutput output, cons "%i\n" "%i\n", context->syslog_identifier ? context->syslog_identifier : ident, + unit_id, context->syslog_priority, !!context->syslog_level_prefix, output == EXEC_OUTPUT_SYSLOG || output == EXEC_OUTPUT_SYSLOG_AND_CONSOLE, @@ -311,7 +313,7 @@ static int setup_input(const ExecContext *context, int socket_fd, bool apply_tty } } -static int setup_output(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) { +static int setup_output(const ExecContext *context, int socket_fd, const char *ident, const char *unit_id, bool apply_tty_stdin) { ExecOutput o; ExecInput i; @@ -358,7 +360,7 @@ static int setup_output(const ExecContext *context, int socket_fd, const char *i case EXEC_OUTPUT_KMSG_AND_CONSOLE: case EXEC_OUTPUT_JOURNAL: case EXEC_OUTPUT_JOURNAL_AND_CONSOLE: - return connect_logger_as(context, o, ident, STDOUT_FILENO); + return connect_logger_as(context, o, ident, unit_id, STDOUT_FILENO); case EXEC_OUTPUT_SOCKET: assert(socket_fd >= 0); @@ -369,7 +371,7 @@ static int setup_output(const ExecContext *context, int socket_fd, const char *i } } -static int setup_error(const ExecContext *context, int socket_fd, const char *ident, bool apply_tty_stdin) { +static int setup_error(const ExecContext *context, int socket_fd, const char *ident, const char *unit_id, bool apply_tty_stdin) { ExecOutput o, e; ExecInput i; @@ -413,7 +415,7 @@ static int setup_error(const ExecContext *context, int socket_fd, const char *id case EXEC_OUTPUT_KMSG_AND_CONSOLE: case EXEC_OUTPUT_JOURNAL: case EXEC_OUTPUT_JOURNAL_AND_CONSOLE: - return connect_logger_as(context, e, ident, STDERR_FILENO); + return connect_logger_as(context, e, ident, unit_id, STDERR_FILENO); case EXEC_OUTPUT_SOCKET: assert(socket_fd >= 0); @@ -913,6 +915,7 @@ int exec_spawn(ExecCommand *command, CGroupBonding *cgroup_bondings, CGroupAttribute *cgroup_attributes, const char *cgroup_suffix, + const char *unit_id, int idle_pipe[2], pid_t *ret) { @@ -1101,14 +1104,14 @@ int exec_spawn(ExecCommand *command, } if (!keep_stdout) { - err = setup_output(context, socket_fd, path_get_file_name(command->path), apply_tty_stdin); + err = setup_output(context, socket_fd, path_get_file_name(command->path), unit_id, apply_tty_stdin); if (err < 0) { r = EXIT_STDOUT; goto fail_child; } } - err = setup_error(context, socket_fd, path_get_file_name(command->path), apply_tty_stdin); + err = setup_error(context, socket_fd, path_get_file_name(command->path), unit_id, apply_tty_stdin); if (err < 0) { r = EXIT_STDERR; goto fail_child; diff --git a/src/core/execute.h b/src/core/execute.h index 6c68169a8..2083c2971 100644 --- a/src/core/execute.h +++ b/src/core/execute.h @@ -192,6 +192,7 @@ int exec_spawn(ExecCommand *command, struct CGroupBonding *cgroup_bondings, struct CGroupAttribute *cgroup_attributes, const char *cgroup_suffix, + const char *unit_id, int pipe_fd[2], pid_t *ret); diff --git a/src/core/mount.c b/src/core/mount.c index b885baab0..3f8cf8a68 100644 --- a/src/core/mount.c +++ b/src/core/mount.c @@ -770,6 +770,7 @@ static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) { UNIT(m)->cgroup_bondings, UNIT(m)->cgroup_attributes, NULL, + UNIT(m)->id, NULL, &pid)) < 0) goto fail; diff --git a/src/core/service.c b/src/core/service.c index 894127167..eeabe8fb0 100644 --- a/src/core/service.c +++ b/src/core/service.c @@ -1810,6 +1810,7 @@ static int service_spawn( UNIT(s)->cgroup_bondings, UNIT(s)->cgroup_attributes, is_control ? "control" : NULL, + UNIT(s)->id, s->type == SERVICE_IDLE ? UNIT(s)->manager->idle_pipe : NULL, &pid); diff --git a/src/core/socket.c b/src/core/socket.c index 633663e7e..ea24f4b44 100644 --- a/src/core/socket.c +++ b/src/core/socket.c @@ -1153,6 +1153,7 @@ static int socket_spawn(Socket *s, ExecCommand *c, pid_t *_pid) { UNIT(s)->cgroup_bondings, UNIT(s)->cgroup_attributes, NULL, + UNIT(s)->id, NULL, &pid); diff --git a/src/core/swap.c b/src/core/swap.c index e7ed1b88d..f3c7fa307 100644 --- a/src/core/swap.c +++ b/src/core/swap.c @@ -590,6 +590,7 @@ static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) { UNIT(s)->cgroup_bondings, UNIT(s)->cgroup_attributes, NULL, + UNIT(s)->id, NULL, &pid)) < 0) goto fail; diff --git a/src/journal/journald.c b/src/journal/journald.c index 1bf25e809..619a98d1f 100644 --- a/src/journal/journald.c +++ b/src/journal/journald.c @@ -77,6 +77,7 @@ typedef enum StdoutStreamState { STDOUT_STREAM_IDENTIFIER, + STDOUT_STREAM_UNIT_ID, STDOUT_STREAM_PRIORITY, STDOUT_STREAM_LEVEL_PREFIX, STDOUT_STREAM_FORWARD_TO_SYSLOG, @@ -97,6 +98,7 @@ struct StdoutStream { #endif char *identifier; + char *unit_id; int priority; bool level_prefix:1; bool forward_to_syslog:1; @@ -458,7 +460,7 @@ static void dispatch_message_real( struct iovec *iovec, unsigned n, unsigned m, struct ucred *ucred, struct timeval *tv, - const char *label, size_t label_len) { + const char *label, size_t label_len, const char *unit_id) { char *pid = NULL, *uid = NULL, *gid = NULL, *source_time = NULL, *boot_id = NULL, *machine_id = NULL, @@ -560,10 +562,11 @@ static void dispatch_message_real( if (cg_pid_get_unit(ucred->pid, &t) >= 0) { unit = strappend("_SYSTEMD_UNIT=", t); free(t); + } else if (unit_id) + unit = strappend("_SYSTEMD_UNIT=", unit_id); - if (unit) - IOVEC_SET_STRING(iovec[n++], unit); - } + if (unit) + IOVEC_SET_STRING(iovec[n++], unit); #ifdef HAVE_SELINUX if (label) { @@ -702,7 +705,7 @@ static void driver_message(Server *s, sd_id128_t message_id, const char *format, ucred.uid = getuid(); ucred.gid = getgid(); - dispatch_message_real(s, iovec, n, ELEMENTSOF(iovec), &ucred, NULL, NULL, 0); + dispatch_message_real(s, iovec, n, ELEMENTSOF(iovec), &ucred, NULL, NULL, 0, NULL); } static void dispatch_message(Server *s, @@ -710,6 +713,7 @@ static void dispatch_message(Server *s, struct ucred *ucred, struct timeval *tv, const char *label, size_t label_len, + const char *unit_id, int priority) { int rl; char *path = NULL, *c; @@ -760,7 +764,7 @@ static void dispatch_message(Server *s, free(path); finish: - dispatch_message_real(s, iovec, n, m, ucred, tv, label, label_len); + dispatch_message_real(s, iovec, n, m, ucred, tv, label, label_len, unit_id); } static void forward_syslog_iovec(Server *s, const struct iovec *iovec, unsigned n_iovec, struct ucred *ucred, struct timeval *tv) { @@ -1126,7 +1130,7 @@ static void process_syslog_message(Server *s, const char *buf, struct ucred *ucr if (message) IOVEC_SET_STRING(iovec[n++], message); - dispatch_message(s, iovec, n, ELEMENTSOF(iovec), ucred, tv, label, label_len, priority); + dispatch_message(s, iovec, n, ELEMENTSOF(iovec), ucred, tv, label, label_len, NULL, priority); free(message); free(identifier); @@ -1204,7 +1208,7 @@ static void process_native_message( if (e == p) { /* Entry separator */ - dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, priority); + dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); n = 0; priority = LOG_INFO; @@ -1354,7 +1358,7 @@ static void process_native_message( forward_console(s, priority, identifier, message, ucred); } - dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, priority); + dispatch_message(s, iovec, n, m, ucred, tv, label, label_len, NULL, priority); finish: for (j = 0; j < n; j++) { @@ -1477,7 +1481,7 @@ static int stdout_stream_log(StdoutStream *s, const char *p) { } #endif - dispatch_message(s->server, iovec, n, ELEMENTSOF(iovec), &s->ucred, NULL, label, label_len, priority); + dispatch_message(s->server, iovec, n, ELEMENTSOF(iovec), &s->ucred, NULL, label, label_len, s->unit_id, priority); free(message); free(syslog_priority); @@ -1508,6 +1512,22 @@ static int stdout_stream_line(StdoutStream *s, char *p) { } } + s->state = STDOUT_STREAM_UNIT_ID; + return 0; + + case STDOUT_STREAM_UNIT_ID: + if (s->ucred.uid == 0) { + if (isempty(p)) + s->unit_id = NULL; + else { + s->unit_id = strdup(p); + if (!s->unit_id) { + log_error("Out of memory"); + return -ENOMEM; + } + } + } + s->state = STDOUT_STREAM_PRIORITY; return 0; @@ -1874,7 +1894,7 @@ static void proc_kmsg_line(Server *s, const char *p) { if (message) IOVEC_SET_STRING(iovec[n++], message); - dispatch_message(s, iovec, n, ELEMENTSOF(iovec), NULL, NULL, NULL, 0, priority); + dispatch_message(s, iovec, n, ELEMENTSOF(iovec), NULL, NULL, NULL, 0, NULL, priority); finish: free(message);