Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miklos Szeredi , syzbot+ef054c4d3f64cd7f7cec@syzkaller.appspotmai Subject: [PATCH 4.9 21/83] fuse: set FR_SENT while locked Date: Mon, 19 Nov 2018 17:28:47 +0100 Message-Id: <20181119162616.050781455@linuxfoundation.org> In-Reply-To: <20181119162612.046511542@linuxfoundation.org> References: <20181119162612.046511542@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Miklos Szeredi commit 4c316f2f3ff315cb48efb7435621e5bfb81df96d upstream. Otherwise fuse_dev_do_write() could come in and finish off the request, and the set_bit(FR_SENT, ...) could trigger the WARN_ON(test_bit(FR_SENT, ...)) in request_end(). Signed-off-by: Miklos Szeredi Reported-by: syzbot+ef054c4d3f64cd7f7cec@syzkaller.appspotmai Fixes: 46c34a348b0a ("fuse: no fc->lock for pqueue parts") Cc: # v4.2 Signed-off-by: Greg Kroah-Hartman --- fs/fuse/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -1311,8 +1311,8 @@ static ssize_t fuse_dev_do_read(struct f } list_move_tail(&req->list, &fpq->processing); __fuse_get_request(req); - spin_unlock(&fpq->lock); set_bit(FR_SENT, &req->flags); + spin_unlock(&fpq->lock); /* matches barrier in request_wait_answer() */ smp_mb__after_atomic(); if (test_bit(FR_INTERRUPTED, &req->flags))