[Libguestfs] [libnbd PATCH v3 22/29] CONNECT_COMMAND.START: check syscalls for errors in the child process
It's bad hygiene to just assume dup2(), close() and signal() will succeed.
Check all return values.
Signed-off-by: Laszlo Ersek <lersek(a)redhat.com>
---
Notes:
context:-U10
generator/states-connect.c | 22 +++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/generator/states-connect.c b/generator/states-connect.c
index e08608336fd6..d2476dc11c60 100644
--- a/generator/states-connect.c
+++ b/generator/states-connect.c
@@ -262,29 +262,41 @@ CONNECT_COMMAND.START:
pid = fork ();
if (pid == -1) {
SET_NEXT_STATE (%.DEAD);
set_error (errno, "fork");
close (sv[0]);
close (sv[1]);
return 0;
}
if (pid == 0) { /* child - run command */
- close (sv[0]);
- dup2 (sv[1], STDIN_FILENO);
- dup2 (sv[1], STDOUT_FILENO);
+ if (close (sv[0]) == -1) {
+ nbd_internal_fork_safe_perror ("close");
+ _exit (126);
+ }
+ if (dup2 (sv[1], STDIN_FILENO) == -1 ||
+ dup2 (sv[1], STDOUT_FILENO) == -1) {
+ nbd_internal_fork_safe_perror ("dup2");
+ _exit (126);
+ }
NBD_INTERNAL_FORK_SAFE_ASSERT (sv[1] != STDIN_FILENO);
NBD_INTERNAL_FORK_SAFE_ASSERT (sv[1] != STDOUT_FILENO);
- close (sv[1]);
+ if (close (sv[1]) == -1) {
+ nbd_internal_fork_safe_perror ("close");
+ _exit (126);
+ }
/* 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);
+ }
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. */