On Wed, Feb 15, 2023 at 03:11:43PM +0100, Laszlo Ersek wrote:
> It's bad hygiene to just assume dup2(), close() and signal() will succeed,
> especially considering the inconsistency that we do check fcntl(). Check
> all return values.
>
> Signed-off-by: Laszlo Ersek <ler...@redhat.com>
> ---
>
> Notes:
> context:-U12
>
> generator/states-connect-socket-activation.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/generator/states-connect-socket-activation.c
> b/generator/states-connect-socket-activation.c
> index 729f37d897fb..766f46177bf3 100644
> --- a/generator/states-connect-socket-activation.c
> +++ b/generator/states-connect-socket-activation.c
> @@ -161,50 +161,59 @@ CONNECT_SA.START:
> }
>
> pid = fork ();
> if (pid == -1) {
> SET_NEXT_STATE (%.DEAD);
> set_error (errno, "fork");
> close (s);
> string_vector_empty (&env);
> return 0;
> }
> if (pid == 0) { /* child - run command */
> if (s != FIRST_SOCKET_ACTIVATION_FD) {
> - dup2 (s, FIRST_SOCKET_ACTIVATION_FD);
> - close (s);
> + if (dup2 (s, FIRST_SOCKET_ACTIVATION_FD) == -1) {
> + nbd_internal_fork_safe_perror ("dup2");
> + _exit (126);
> + }
> + if (close (s) == -1) {
> + nbd_internal_fork_safe_perror ("close");
> + _exit (126);
> + }
> }
> else {
> /* We must unset CLOEXEC on the fd. (dup2 above does this
> * implicitly because CLOEXEC is set on the fd, not on the
> * socket).
> */
> int flags = fcntl (s, F_GETFD, 0);
> if (flags == -1) {
> nbd_internal_fork_safe_perror ("fcntl: F_GETFD");
> _exit (126);
> }
> if (fcntl (s, F_SETFD, (int)(flags & ~(unsigned)FD_CLOEXEC)) == -1) {
> nbd_internal_fork_safe_perror ("fcntl: F_SETFD");
> _exit (126);
> }
> }
>
> char buf[32];
> const char *v =
> nbd_internal_fork_safe_itoa ((long) getpid (), buf, sizeof buf);
> strcpy (&env.ptr[0][PREFIX_LENGTH], v);
>
> /* Restore SIGPIPE back to SIG_DFL. */
> - signal (SIGPIPE, SIG_DFL);
> + if (signal (SIGPIPE, SIG_DFL) == SIG_ERR) {
> + nbd_internal_fork_safe_perror ("signal");
> + _exit (126);
> + }
>
> environ = env.ptr;
> execvp (h->argv.ptr[0], h->argv.ptr);
> nbd_internal_fork_safe_perror (h->argv.ptr[0]);
> if (errno == ENOENT)
> _exit (127);
> else
> _exit (126);
> }
>
> /* Parent. */
> close (s);
Reviewed-by: Richard W.M. Jones <rjo...@redhat.com>
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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