io_uring: don't submit link on error

If we get an error in io_init_req() for a request that would have been
linked, we break the submission but still issue a partially composed
link, that's nasty, fail it instead.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index fe2379179b006cef9ecd3277797582f41c50cf10..62688866357cf782b4897f66259d14c06a71a00c 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6763,6 +6763,9 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
 fail_req:
                io_put_req(req);
                io_req_complete(req, ret);
+               /* fail even hard links since we don't submit */
+               if (link->head)
+                       link->head->flags |= REQ_F_FAIL_LINK;
                return ret;
        }
 
@@ -6791,11 +6794,8 @@ fail_req:
                        ctx->drain_next = 1;
                }
                ret = io_req_defer_prep(req, sqe);
-               if (unlikely(ret)) {
-                       /* fail even hard links since we don't submit */
-                       head->flags |= REQ_F_FAIL_LINK;
+               if (unlikely(ret))
                        goto fail_req;
-               }
                trace_io_uring_link(ctx, req, head);
                link->last->link = req;
                link->last = req;