From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3F594C2D0C3 for ; Tue, 17 Dec 2019 00:59:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1FF9D206D3 for ; Tue, 17 Dec 2019 00:59:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727742AbfLQA7s (ORCPT ); Mon, 16 Dec 2019 19:59:48 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34684 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726692AbfLQAvf (ORCPT ); Mon, 16 Dec 2019 19:51:35 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1ih15G-0003Jx-Hx; Tue, 17 Dec 2019 00:51:30 +0000 Received: from ben by deadeye with local (Exim 4.93-RC7) (envelope-from ) id 1ih15F-0005Sp-Oy; Tue, 17 Dec 2019 00:51:29 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Tomoki Sekiyama" , "Alan Stern" , "Greg Kroah-Hartman" Date: Tue, 17 Dec 2019 00:45:54 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 020/136] USB: yurex: Don't retry on unexpected errors In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.16.80-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 32a0721c6620b77504916dac0cea8ad497c4878a upstream. According to Greg KH, it has been generally agreed that when a USB driver encounters an unknown error (or one it can't handle directly), it should just give up instead of going into a potentially infinite retry loop. The three codes -EPROTO, -EILSEQ, and -ETIME fall into this category. They can be caused by bus errors such as packet loss or corruption, attempting to communicate with a disconnected device, or by malicious firmware. Nowadays the extent of packet loss or corruption is negligible, so it should be safe for a driver to give up whenever one of these errors occurs. Although the yurex driver handles -EILSEQ errors in this way, it doesn't do the same for -EPROTO (as discovered by the syzbot fuzzer) or other unrecognized errors. This patch adjusts the driver so that it doesn't log an error message for -EPROTO or -ETIME, and it doesn't retry after any errors. Reported-and-tested-by: syzbot+b24d736f18a1541ad550@syzkaller.appspotmail.com Signed-off-by: Alan Stern CC: Tomoki Sekiyama Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.1909171245410.1590-100000@iolanthe.rowland.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/misc/yurex.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/usb/misc/yurex.c +++ b/drivers/usb/misc/yurex.c @@ -136,6 +136,7 @@ static void yurex_interrupt(struct urb * switch (status) { case 0: /*success*/ break; + /* The device is terminated or messed up, give up */ case -EOVERFLOW: dev_err(&dev->interface->dev, "%s - overflow with length %d, actual length is %d\n", @@ -144,12 +145,13 @@ static void yurex_interrupt(struct urb * case -ENOENT: case -ESHUTDOWN: case -EILSEQ: - /* The device is terminated, clean up */ + case -EPROTO: + case -ETIME: return; default: dev_err(&dev->interface->dev, "%s - unknown status received: %d\n", __func__, status); - goto exit; + return; } /* handle received message */ @@ -181,7 +183,6 @@ static void yurex_interrupt(struct urb * break; } -exit: retval = usb_submit_urb(dev->urb, GFP_ATOMIC); if (retval) { dev_err(&dev->interface->dev, "%s - usb_submit_urb failed: %d\n",