Revert "io_uring: only allow submit from owning task"

commit 73e08e711d9c1d79fae01daed4b0e1fee5f8a275 upstream.

This ends up being too restrictive for tasks that willingly fork and
share the ring between forks. Andres reports that this breaks his
postgresql work. Since we're close to 5.5 release, revert this change
for now.

Cc: stable@vger.kernel.org
Fixes: 44d282796f81 ("io_uring: only allow submit from owning task")
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index b1c9ad1fb9e1023096051c53961dffcfff03a755..709671faaed629bcc2673d893168c8807c0bb4bd 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3716,12 +3716,6 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
                        wake_up(&ctx->sqo_wait);
                submitted = to_submit;
        } else if (to_submit) {
-               if (current->mm != ctx->sqo_mm ||
-                   current_cred() != ctx->creds) {
-                       ret = -EPERM;
-                       goto out;
-               }
-
                to_submit = min(to_submit, ctx->sq_entries);
 
                mutex_lock(&ctx->uring_lock);