From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from r3-11.sinamail.sina.com.cn (r3-11.sinamail.sina.com.cn [202.108.3.11]) (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 1B4251B81CA for ; Sat, 21 Feb 2026 13:40:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771681236; cv=none; b=S437HmA11vn90K/xBmBMcN7V1ZPKwcKZYuzQ4aj0j1VZrnTOSJUKmxW5ZjLszPI3/FAgHpVJeJwFgRkPjFqW7LKtJQdMW+OINejmtiZ3rzBXUQm9nkgsfa3KrWKKPB2Vxa4k7cqJpwSs7zqvVV9a6nrueYRNthomq/1vu1Kn3Ks= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771681236; c=relaxed/simple; bh=edfQ2oCJtRLIxnzwXEHJ0xPERMJwUKLaOkSoGs98UQ4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G2xWLtKfIiXX3DJLr/xKT5LXNrAxsFbz4k3CZyd1daFoNmdRQMoiLboT6TWSe2A+kX/GqsVwCzYYAmYwvKcmRE2LDp4u3o71RxurbZmuvpnqtDooDAY+lcO7FMgwtMyHbSRt8BU2nwMg58alft4y0RgcfyIyKeQoPsGfoGTo6Kc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=y8tXSfue; arc=none smtp.client-ip=202.108.3.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="y8tXSfue" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1771681232; bh=wv/4xUIJuQacqMPncFcBF8DsyJ/2MnpWTgVwsBMtV6g=; h=From:Subject:Date:Message-ID; b=y8tXSfueNGqe4Lad8HqmE5THP+Ou3M1hVWugEt5wO/MV/QuwqwDTXaQ1+jRbemrCY b+2SVFk8vnJp43nR9N+eNfgksxCMpf25DPkL3DbzBA0VCYs8HX1MEacR9kRh1SACyd zpqNg8c+K9dWmO8SyCyqBuRAeoFQ8DkAhrg/2eBQ= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.62.144]) by sina.com (10.54.253.34) with ESMTP id 6999B5C200006D52; Sat, 21 Feb 2026 21:40:22 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 8409396291739 X-SMAIL-UIID: 0973DFF9BC5044229B69654179401E2F-20260221-214022-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [media?] KASAN: slab-use-after-free Read in dvb_frontend_release (3) Date: Sat, 21 Feb 2026 21:40:09 +0800 Message-ID: <20260221134010.3248-1-hdanton@sina.com> In-Reply-To: <6992e4aa.a70a0220.2c38d7.00e9.GAE@google.com> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Mon, 16 Feb 2026 01:34:34 -0800 [thread overview] > syzbot has found a reproducer for the following issue on: > > HEAD commit: c22e26bd0906 Merge tag 'landlock-7.0-rc1' of git://git.ker.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=16bcf6e6580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=6428d17febdfb14e > dashboard link: https://syzkaller.appspot.com/bug?extid=ae466a728017ec940b41 > compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15ce3652580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1121515a580000 #syz test --- x/drivers/media/dvb-core/dvb_frontend.c +++ y/drivers/media/dvb-core/dvb_frontend.c @@ -2911,6 +2911,7 @@ static int dvb_frontend_release(struct i mb(); } + dvb_device_get(dvbdev); ret = dvb_generic_release(inode, file); if (dvbdev->users == -1) { @@ -2930,6 +2931,7 @@ static int dvb_frontend_release(struct i if (fe->ops.ts_bus_ctrl) fe->ops.ts_bus_ctrl(fe, 0); } + dvb_device_put(dvbdev); dvb_frontend_put(fe); --