From: Pavel Begunkov <asml.silence@gmail.com>
Date: Sat, 30 May 2020 11:19:15 +0000 (+0300)
Subject: io_uring: fix overflowed reqs cancellation
X-Git-Tag: v5.15~3748^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7b53d59859bc932b37895d2d37388e7fa29af7a5;p=platform%2Fkernel%2Flinux-starfive.git

io_uring: fix overflowed reqs cancellation

Overflowed requests in io_uring_cancel_files() should be shed only of
inflight and overflowed refs. All other left references are owned by
someone else.

If refcount_sub_and_test() fails, it will go further and put put extra
ref, don't do that. Also, don't need to do io_wq_cancel_work()
for overflowed reqs, they will be let go shortly anyway.

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 9f11feb..732ec73 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7449,10 +7449,11 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx,
 				finish_wait(&ctx->inflight_wait, &wait);
 				continue;
 			}
+		} else {
+			io_wq_cancel_work(ctx->io_wq, &cancel_req->work);
+			io_put_req(cancel_req);
 		}
 
-		io_wq_cancel_work(ctx->io_wq, &cancel_req->work);
-		io_put_req(cancel_req);
 		schedule();
 		finish_wait(&ctx->inflight_wait, &wait);
 	}