diff options
Diffstat (limited to 'src/process/posix_spawn.c')
| -rw-r--r-- | src/process/posix_spawn.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/src/process/posix_spawn.c b/src/process/posix_spawn.c index c6886526..eb98f9f6 100644 --- a/src/process/posix_spawn.c +++ b/src/process/posix_spawn.c @@ -20,29 +20,43 @@ struct args { char *const *argv, *const *envp; }; +void __get_handler_set(sigset_t *); + static int child(void *args_vp) { int i, ret; - struct sigaction sa; + struct sigaction sa = {0}; struct args *args = args_vp; int p = args->p[1]; const posix_spawn_file_actions_t *fa = args->fa; const posix_spawnattr_t *restrict attr = args->attr; + sigset_t hset; close(args->p[0]); /* All signal dispositions must be either SIG_DFL or SIG_IGN * before signals are unblocked. Otherwise a signal handler * from the parent might get run in the child while sharing - * memory, with unpredictable and dangerous results. */ + * memory, with unpredictable and dangerous results. To + * reduce overhead, sigaction has tracked for us which signals + * potentially have a signal handler. */ + __get_handler_set(&hset); for (i=1; i<_NSIG; i++) { - __libc_sigaction(i, 0, &sa); - if (sa.sa_handler!=SIG_DFL && (sa.sa_handler!=SIG_IGN || - ((attr->__flags & POSIX_SPAWN_SETSIGDEF) - && sigismember(&attr->__def, i) ))) { + if ((attr->__flags & POSIX_SPAWN_SETSIGDEF) + && sigismember(&attr->__def, i)) { sa.sa_handler = SIG_DFL; - __libc_sigaction(i, &sa, 0); + } else if (sigismember(&hset, i)) { + if (i-32<3U) { + sa.sa_handler = SIG_IGN; + } else { + __libc_sigaction(i, 0, &sa); + if (sa.sa_handler==SIG_IGN) continue; + sa.sa_handler = SIG_DFL; + } + } else { + continue; } + __libc_sigaction(i, &sa, 0); } if (attr->__flags & POSIX_SPAWN_SETPGROUP) |