coredump: fix error handling for replace_fd()

commit 95c5f43181fe9c1b5e5a4bd3281c857a5259991f upstream.

The replace_fd() helper returns the file descriptor number on success
and a negative error code on failure. The current error handling in
umh_pipe_setup() only works because the file descriptor that is replaced
is zero but that's pretty volatile. Explicitly check for a negative
error code.

Link: https://lore.kernel.org/20250414-work-coredump-v2-2-685bf231f828@kernel.org
Tested-by: Luca Boccassi <luca.boccassi@gmail.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Christian Brauner
2025-04-14 15:55:06 +02:00
committed by Greg Kroah-Hartman
parent 0ec1e98bf5
commit 1846a7b92b

View File

@@ -502,7 +502,9 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
{
struct file *files[2];
struct coredump_params *cp = (struct coredump_params *)info->data;
int err = create_pipe_files(files, 0);
int err;
err = create_pipe_files(files, 0);
if (err)
return err;
@@ -510,10 +512,13 @@ static int umh_pipe_setup(struct subprocess_info *info, struct cred *new)
err = replace_fd(0, files[0], 0);
fput(files[0]);
if (err < 0)
return err;
/* and disallow core files too */
current->signal->rlim[RLIMIT_CORE] = (struct rlimit){1, 1};
return err;
return 0;
}
void do_coredump(const kernel_siginfo_t *siginfo)