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/vconsole/vconsole-setup.c | 26 ++++++++++---------------- 1 file changed, 10 insertions(+), 16 deletions(-) (limited to 'src/vconsole') diff --git a/src/vconsole/vconsole-setup.c b/src/vconsole/vconsole-setup.c index e19a1637bf..fdc7c5f974 100644 --- a/src/vconsole/vconsole-setup.c +++ b/src/vconsole/vconsole-setup.c @@ -133,6 +133,7 @@ static int keyboard_load_and_wait(const char *vc, const char *map, const char *m const char *args[8]; unsigned i = 0; pid_t pid; + int r; /* An empty map means kernel map */ if (isempty(map)) @@ -152,14 +153,10 @@ static int keyboard_load_and_wait(const char *vc, const char *map, const char *m log_debug("Executing \"%s\"...", strnull((cmd = strv_join((char**) args, " ")))); - pid = fork(); - if (pid < 0) - return log_error_errno(errno, "Failed to fork: %m"); - else if (pid == 0) { - - (void) reset_all_signal_handlers(); - (void) reset_signal_mask(); - + r = safe_fork("(loadkeys)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS, &pid); + if (r < 0) + return log_error_errno(r, "Failed to fork: %m"); + if (r == 0) { execv(args[0], (char **) args); _exit(EXIT_FAILURE); } @@ -172,6 +169,7 @@ static int font_load_and_wait(const char *vc, const char *font, const char *map, const char *args[9]; unsigned i = 0; pid_t pid; + int r; /* Any part can be set independently */ if (isempty(font) && isempty(map) && isempty(unimap)) @@ -195,14 +193,10 @@ static int font_load_and_wait(const char *vc, const char *font, const char *map, log_debug("Executing \"%s\"...", strnull((cmd = strv_join((char**) args, " ")))); - pid = fork(); - if (pid < 0) - return log_error_errno(errno, "Failed to fork: %m"); - else if (pid == 0) { - - (void) reset_all_signal_handlers(); - (void) reset_signal_mask(); - + r = safe_fork("(setfont)", FORK_RESET_SIGNALS|FORK_CLOSE_ALL_FDS, &pid); + if (r < 0) + return log_error_errno(r, "Failed to fork: %m"); + if (r == 0) { execv(args[0], (char **) args); _exit(EXIT_FAILURE); } -- cgit v1.2.3