diff options
Diffstat (limited to 'src/process/posix_spawn.c')
| -rw-r--r-- | src/process/posix_spawn.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/src/process/posix_spawn.c b/src/process/posix_spawn.c index 29652197..8294598b 100644 --- a/src/process/posix_spawn.c +++ b/src/process/posix_spawn.c @@ -4,8 +4,10 @@ #include <unistd.h> #include <signal.h> #include <fcntl.h> +#include <errno.h> #include <sys/wait.h> #include "syscall.h" +#include "lock.h" #include "pthread_impl.h" #include "fdop.h" @@ -155,7 +157,11 @@ static int child(void *args_vp) fail: /* Since sizeof errno < PIPE_BUF, the write is atomic. */ ret = -ret; - if (ret) while (__syscall(SYS_write, p, &ret, sizeof ret) < 0); + if (ret) { + int r; + do r = __syscall(SYS_write, p, &ret, sizeof ret); + while (r<0 && r!=-EPIPE); + } _exit(127); } @@ -170,9 +176,6 @@ int posix_spawn(pid_t *restrict res, const char *restrict path, int ec=0, cs; struct args args; - if (pipe2(args.p, O_CLOEXEC)) - return errno; - pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs); args.path = path; @@ -182,9 +185,20 @@ int posix_spawn(pid_t *restrict res, const char *restrict path, args.envp = envp; pthread_sigmask(SIG_BLOCK, SIGALL_SET, &args.oldmask); + /* The lock guards both against seeing a SIGABRT disposition change + * by abort and against leaking the pipe fd to fork-without-exec. */ + LOCK(__abort_lock); + + if (pipe2(args.p, O_CLOEXEC)) { + UNLOCK(__abort_lock); + ec = errno; + goto fail; + } + pid = __clone(child, stack+sizeof stack, CLONE_VM|CLONE_VFORK|SIGCHLD, &args); close(args.p[1]); + UNLOCK(__abort_lock); if (pid > 0) { if (read(args.p[0], &ec, sizeof ec) != sizeof ec) ec = 0; @@ -197,6 +211,7 @@ int posix_spawn(pid_t *restrict res, const char *restrict path, if (!ec && res) *res = pid; +fail: pthread_sigmask(SIG_SETMASK, &args.oldmask, 0); pthread_setcancelstate(cs, 0); |