diff options
| author | Rich Felker <dalias@aerifal.cx> | 2012-10-19 15:02:37 -0400 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2012-10-19 15:02:37 -0400 |
| commit | 599f97360389911c293e0ca4c5eb49e007377fba (patch) | |
| tree | 9df3f1e50357956c4cc76cd8e2872f342c80bf3c | |
| parent | ebee8c2b477807fe58fd35d35783633ea08b049c (diff) | |
| download | musl-599f97360389911c293e0ca4c5eb49e007377fba.tar.gz musl-599f97360389911c293e0ca4c5eb49e007377fba.tar.bz2 musl-599f97360389911c293e0ca4c5eb49e007377fba.tar.xz musl-599f97360389911c293e0ca4c5eb49e007377fba.zip | |
fix usage of locks with vfork
__release_ptc() is only valid in the parent; if it's performed in the
child, the lock will be unlocked early then double-unlocked later,
corrupting the lock state.
| -rw-r--r-- | src/process/posix_spawn.c | 2 | ||||
| -rw-r--r-- | src/process/system.c | 3 | ||||
| -rw-r--r-- | src/stdio/popen.c | 2 |
3 files changed, 4 insertions, 3 deletions
diff --git a/src/process/posix_spawn.c b/src/process/posix_spawn.c index c3e800b8..5eb516b0 100644 --- a/src/process/posix_spawn.c +++ b/src/process/posix_spawn.c @@ -35,9 +35,9 @@ int __posix_spawnx(pid_t *restrict res, const char *restrict path, __acquire_ptc(); pid = __vfork(); - __release_ptc(); if (pid) { + __release_ptc(); sigprocmask(SIG_SETMASK, &oldmask, 0); if (pid < 0) return -pid; *res = pid; diff --git a/src/process/system.c b/src/process/system.c index c8f26008..ebe207f5 100644 --- a/src/process/system.c +++ b/src/process/system.c @@ -29,7 +29,8 @@ int system(const char *cmd) __acquire_ptc(); pid = __vfork(); - __release_ptc(); + + if (pid) __release_ptc(); if (pid > 0) { sigset_t new = old; diff --git a/src/stdio/popen.c b/src/stdio/popen.c index 0c9f24e3..5a47509e 100644 --- a/src/stdio/popen.c +++ b/src/stdio/popen.c @@ -38,9 +38,9 @@ FILE *popen(const char *cmd, const char *mode) __acquire_ptc(); pid = __vfork(); - __release_ptc(); if (pid) { + __release_ptc(); __syscall(SYS_close, p[1-op]); sigprocmask(SIG_BLOCK, SIGALL_SET, &old); if (pid < 0) { |