From patchwork Tue Jun 8 14:04:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takashi Iwai X-Patchwork-Id: 455878 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 91190C47082 for ; Tue, 8 Jun 2021 14:09:57 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1DE8C60FE9 for ; Tue, 8 Jun 2021 14:09:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1DE8C60FE9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id C0DF41717; Tue, 8 Jun 2021 16:09:05 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz C0DF41717 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1623161395; bh=ctK53MDcd7HJ+YhqD/qQxvRVdabwy/t+BvA1U+GegK8=; h=From:To:Subject:Date:In-Reply-To:References:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=Ye2Edz213P/OvY9LjK1nlS+6ph/c1TafVnYxGu837JkQMiDDFKDBc1KLOjoeyRms3 EhJcyMgInbUL27I7Kfm9m9czazL1RqIW1qvXfZfwcsyqWz86FFOjD1lzQssYUe8soV 8riyvh+ZT2jfFvAmB28ddZUs/msdryrGUQpXugKo= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 1BF92F8055A; Tue, 8 Jun 2021 16:06:11 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 1BF7AF80557; Tue, 8 Jun 2021 16:06:07 +0200 (CEST) Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 091C0F804C2 for ; Tue, 8 Jun 2021 16:05:43 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 091C0F804C2 Authentication-Results: alsa1.perex.cz; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.b="SqxNeqac"; dkim=permerror (0-bit key) header.d=suse.de header.i=@suse.de header.b="ZpHDB+99" Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id A6CBF21956 for ; Tue, 8 Jun 2021 14:05:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1623161142; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ENsinWi7lONbu091FCneoMX/KYLLPwssYarjCCW12YU=; b=SqxNeqacc934d9u4E/1NDMQUE8u3X+ADGjGBdM+0N0v+JDCS+0K/+Wky96rIYty6YhkvCQ 1ecSDSSF3FQINYzQaoLorpFfCMEcv9j2ulkQ7S8JZ/vSGIsom+co6IUaq4uthNhr5QvC9S VwWi4AGXJRw9c5GS2KD2wwjuY3nf1Vs= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1623161142; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ENsinWi7lONbu091FCneoMX/KYLLPwssYarjCCW12YU=; b=ZpHDB+99zwT93qVDw8fcl4VTXKz9TJ64u8ixcc9KlNMxYWXJip1ZuAlxORo5PcK0yCuu9C uRKlbozvjfM7vBAg== Received: from alsa1.nue.suse.com (alsa1.suse.de [10.160.4.42]) by relay2.suse.de (Postfix) with ESMTP id 97E7EA3B84; Tue, 8 Jun 2021 14:05:42 +0000 (UTC) From: Takashi Iwai To: alsa-devel@alsa-project.org Subject: [PATCH 03/66] ALSA: sb: Fix potential double-free of CSP mixer elements Date: Tue, 8 Jun 2021 16:04:37 +0200 Message-Id: <20210608140540.17885-4-tiwai@suse.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210608140540.17885-1-tiwai@suse.de> References: <20210608140540.17885-1-tiwai@suse.de> MIME-Version: 1.0 X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" snd_sb_qsound_destroy() contains the calls of removing the previously created mixer controls, but it doesn't clear the pointers. As snd_sb_qsound_destroy() itself may be repeatedly called via ioctl, this could lead to double-free potentially. Fix it by clearing the struct fields properly afterwards. Signed-off-by: Takashi Iwai --- sound/isa/sb/sb16_csp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/sound/isa/sb/sb16_csp.c b/sound/isa/sb/sb16_csp.c index dec68ae6b599..5bbe6695689d 100644 --- a/sound/isa/sb/sb16_csp.c +++ b/sound/isa/sb/sb16_csp.c @@ -1077,10 +1077,14 @@ static void snd_sb_qsound_destroy(struct snd_sb_csp * p) card = p->chip->card; down_write(&card->controls_rwsem); - if (p->qsound_switch) + if (p->qsound_switch) { snd_ctl_remove(card, p->qsound_switch); - if (p->qsound_space) + p->qsound_switch = NULL; + } + if (p->qsound_space) { snd_ctl_remove(card, p->qsound_space); + p->qsound_space = NULL; + } up_write(&card->controls_rwsem); /* cancel pending transfer of QSound parameters */