From nobody Tue Jun 16 18:25:07 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 18CE8175D53; Thu, 30 Apr 2026 03:00:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777518029; cv=none; b=tfl7vfT2wL6wpaDarJtZixexTTL28Fyp8B+01plxD3VAm77s2Q7PpNnYFZjWFvDu3dfFxEg1KbsbK0gjc8DONp1Z3myuvQYfs7KXkO/NT7t6YmSAcDnYVmbPAmOYoLoq00mNGVHSNyr3o2iYYWLfUqZc6b7EMe2EehdgzvLUmrI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777518029; c=relaxed/simple; bh=tfyj8S0FzN85evNnhvxUMPHahJtLkbkIRBZ94QaxhRs=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=plPTJRaGlLR+X5vs3ymlWiVzDE47FEngjbYvGbO0WAbPkgjN13CBjDTc7gXCFLrTPqcrLX19YyWmRHfpDJI9KzKsKaVF74qAB7QLvhINPViw4oBCh9Y82d49lKFZ1KO/h+LoOvNzlctV5DpCtZtfSHxkNQDIzN7whaSyGz1VSyM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: b8c5f6f4444011f1aa26b74ffac11d73-20260430 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:8ac1ad45-1c73-44ba-8b53-9eb5e4941c8d,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:e7bac3a,CLOUDID:46912bda503a4db14864e577c3ea10e3,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|850|898,TC:nil,Content:0|15|50,EDM:- 3,IP:nil,URL:99|1,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA: 0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR,TF_CID_SPAM_ULS X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: b8c5f6f4444011f1aa26b74ffac11d73-20260430 X-User: songxiebing@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1573180281; Thu, 30 Apr 2026 11:00:19 +0800 From: songxiebing To: tiwai@suse.com, perex@perex.cz Cc: linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org, songxiebing@kylinos.cn, syzbot+e29d28728f38190cecfc@syzkaller.appspotmail.com Subject: [PATCH] ALSA: pcm: Fix UAF in snd_pcm_post_stop Date: Thu, 30 Apr 2026 11:00:14 +0800 Message-Id: <20260430030014.259007-1-songxiebing@kylinos.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Bob Song Syzbot reported use-after-free in snd_pcm_post_stop when accessing runtime->sleep / runtime->state. The runtime struct may have been freed already by io_uring async operations, so check for NULL before accessing. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+e29d28728f38190cecfc@syzkaller.appspotmail.com Closes: https://lore.kernel.org/alsa-devel/00000000000060fb5d05f2203601@goo= gle.com/ Signed-off-by: Bob Song --- sound/core/pcm_native.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c index a541bb235cfa..31ea23218d6a 100644 --- a/sound/core/pcm_native.c +++ b/sound/core/pcm_native.c @@ -1561,6 +1561,10 @@ static void snd_pcm_post_stop(struct snd_pcm_substre= am *substream, snd_pcm_state_t state) { struct snd_pcm_runtime *runtime =3D substream->runtime; + + if (!runtime) + return; + if (runtime->state !=3D state) { snd_pcm_trigger_tstamp(substream); __snd_pcm_set_state(runtime, state); --=20 2.25.1