From 4c253ed1cae8b4df72ce1353ee826a4fae399e25 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Fri, 22 Dec 2017 13:08:14 +0100 Subject: tree-wide: introduce new safe_fork() helper and port everything over MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds a new safe_fork() wrapper around fork() and makes use of it everywhere. The new wrapper does a couple of things we previously did manually and separately in a safer, more correct and automatic way: 1. Optionally resets signal handlers/mask in the child 2. Sets a name on all processes we fork off right after forking off (and the patch assigns useful names for all processes we fork off now, following a systematic naming scheme: always enclosed in () – in order to indicate that these are not proper, exec()ed processes, but only forked off children, and if the process is long-running with only our own code, without execve()'ing something else, it gets am "sd-" prefix.) 3. Optionally closes all file descriptors in the child 4. Optionally sets a PR_SET_DEATHSIG to SIGTERM in the child, in a safe way so that the parent dying before this happens being handled safely. 5. Optionally reopens the logs 6. Optionally connects stdin/stdout/stderr to /dev/null 7. Debug logs about the forked off processes. --- src/remount-fs/remount-fs.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) (limited to 'src/remount-fs') diff --git a/src/remount-fs/remount-fs.c b/src/remount-fs/remount-fs.c index 2d7cf723f4..1f0397cf6f 100644 --- a/src/remount-fs/remount-fs.c +++ b/src/remount-fs/remount-fs.c @@ -87,19 +87,14 @@ int main(int argc, char *argv[]) { log_debug("Remounting %s", me->mnt_dir); - pid = fork(); - if (pid < 0) { - r = log_error_errno(errno, "Failed to fork: %m"); + r = safe_fork("(remount)", FORK_RESET_SIGNALS|FORK_DEATHSIG, &pid); + if (r < 0) { + log_error_errno(r, "Failed to fork: %m"); goto finish; } - - if (pid == 0) { + if (r == 0) { /* Child */ - (void) reset_all_signal_handlers(); - (void) reset_signal_mask(); - (void) prctl(PR_SET_PDEATHSIG, SIGTERM); - execv(MOUNT_PATH, STRV_MAKE(MOUNT_PATH, me->mnt_dir, "-o", "remount")); log_error_errno(errno, "Failed to execute " MOUNT_PATH ": %m"); -- cgit v1.2.1