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 16179C43603 for ; Tue, 17 Dec 2019 00:54:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE30424673 for ; Tue, 17 Dec 2019 00:54:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728123AbfLQAyS (ORCPT ); Mon, 16 Dec 2019 19:54:18 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35532 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727185AbfLQAvo (ORCPT ); Mon, 16 Dec 2019 19:51:44 -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 1ih15N-0003P8-KJ; Tue, 17 Dec 2019 00:51:37 +0000 Received: from ben by deadeye with local (Exim 4.93-RC7) (envelope-from ) id 1ih15L-0005ei-6s; Tue, 17 Dec 2019 00:51:35 +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 , "Takashi Iwai" Date: Tue, 17 Dec 2019 00:47:39 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 125/136] ALSA: usb-audio: Fix missing error check at mixer resolution test 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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.80-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai commit 167beb1756791e0806365a3f86a0da10d7a327ee upstream. A check of the return value from get_cur_mix_raw() is missing at the resolution test code in get_min_max_with_quirks(), which may leave the variable untouched, leading to a random uninitialized value, as detected by syzkaller fuzzer. Add the missing return error check for fixing that. Reported-and-tested-by: syzbot+abe1ab7afc62c6bb6377@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20191109181658.30368-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings --- sound/usb/mixer.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -1014,7 +1014,8 @@ static int get_min_max_with_quirks(struc if (cval->min + cval->res < cval->max) { int last_valid_res = cval->res; int saved, test, check; - get_cur_mix_raw(cval, minchn, &saved); + if (get_cur_mix_raw(cval, minchn, &saved) < 0) + goto no_res_check; for (;;) { test = saved; if (test < cval->max) @@ -1034,6 +1035,7 @@ static int get_min_max_with_quirks(struc set_cur_mix_value(cval, minchn, 0, saved); } +no_res_check: cval->initialized = 1; }