From nobody Fri Dec 19 20:52:41 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5EEAAC32772 for ; Tue, 23 Aug 2022 09:29:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350330AbiHWJ3U (ORCPT ); Tue, 23 Aug 2022 05:29:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50184 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1351110AbiHWJ0l (ORCPT ); Tue, 23 Aug 2022 05:26:41 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9A266910B0; Tue, 23 Aug 2022 01:37:04 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7507B6152E; Tue, 23 Aug 2022 08:36:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 822DEC433D6; Tue, 23 Aug 2022 08:36:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661243766; bh=XnKHTAqr4cw2+DZhxkmwjc8pnDzf654pxG/zleJA8kA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PeVzG1S4mV3C5B+k0tyJGMXAu8ohzQ20k8+lMWUs5PyLyyun9NDO7r3pC6Q+GMrvz f7G0jLI0gGVMZqBpzn4vnvXn0pdHXgYackmjoZunJvq1CYGZX2bZA16lYcTOQum2dr rnF8V4TYrt6NmTY3acs9+rOw4vNo2RRcKokOGjPQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zheyu Ma , Takashi Iwai Subject: [PATCH 4.14 015/229] ALSA: bcd2000: Fix a UAF bug on the error path of probing Date: Tue, 23 Aug 2022 10:22:56 +0200 Message-Id: <20220823080053.954612763@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080053.202747790@linuxfoundation.org> References: <20220823080053.202747790@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Zheyu Ma commit ffb2759df7efbc00187bfd9d1072434a13a54139 upstream. When the driver fails in snd_card_register() at probe time, it will free the 'bcd2k->midi_out_urb' before killing it, which may cause a UAF bug. The following log can reveal it: [ 50.727020] BUG: KASAN: use-after-free in bcd2000_input_complete+0x1f1/0= x2e0 [snd_bcd2000] [ 50.727623] Read of size 8 at addr ffff88810fab0e88 by task swapper/4/0 [ 50.729530] Call Trace: [ 50.732899] bcd2000_input_complete+0x1f1/0x2e0 [snd_bcd2000] Fix this by adding usb_kill_urb() before usb_free_urb(). Fixes: b47a22290d58 ("ALSA: MIDI driver for Behringer BCD2000 USB device") Signed-off-by: Zheyu Ma Cc: Link: https://lore.kernel.org/r/20220715010515.2087925-1-zheyuma97@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/bcd2000/bcd2000.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/sound/usb/bcd2000/bcd2000.c +++ b/sound/usb/bcd2000/bcd2000.c @@ -357,7 +357,8 @@ static int bcd2000_init_midi(struct bcd2 static void bcd2000_free_usb_related_resources(struct bcd2000 *bcd2k, struct usb_interface *interface) { - /* usb_kill_urb not necessary, urb is aborted automatically */ + usb_kill_urb(bcd2k->midi_out_urb); + usb_kill_urb(bcd2k->midi_in_urb); =20 usb_free_urb(bcd2k->midi_out_urb); usb_free_urb(bcd2k->midi_in_urb);