From a1be6c19a028adcb29924af7dd3aedf8e036001a Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Tue, 26 May 2020 20:34:02 +0300 Subject: [PATCH 1523/2944] io_uring: fix flush req->refs underflow to #28736503 commit 4518a3cc273cf82efdd36522fb1f13baad173c70 upstream In io_uring_cancel_files(), after refcount_sub_and_test() leaves 0 req->refs, it calls io_put_req(), which would also put a ref. Call io_free_req() instead. Cc: stable@vger.kernel.org Fixes: 2ca10259b418 ("io_uring: prune request from overflow list on flush") Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe Signed-off-by: Xiaoguang Wang Acked-by: Joseph Qi --- fs/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index d1715ba..2434ea5 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7446,7 +7446,7 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx, * all we had, then we're done with this request. */ if (refcount_sub_and_test(2, &cancel_req->refs)) { - io_put_req(cancel_req); + io_free_req(cancel_req); finish_wait(&ctx->inflight_wait, &wait); continue; } -- 1.8.3.1