From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from r3-25.sinamail.sina.com.cn (r3-25.sinamail.sina.com.cn [202.108.3.25]) (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 B1C121D88B4 for ; Sun, 22 Feb 2026 12:15:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.108.3.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771762535; cv=none; b=uOl6jid85UyYi3CRXzh8TtECFJgxtml1Z3SrDShTI5rOtcgG1lrlBcB0/usnGewpkNeifv3FmNc0OZTU6p1p+n7MgPW5gEy2OFSv9KA/hKBxx/mj5YT6Va5t1dpSGXfzW6TOAYDOlXX41eBazjgP6pNZnrY2hvSUhpZVPewNgAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771762535; c=relaxed/simple; bh=4jW6KF/SESrzNUZKJMM6seoRi6/w7rdUqvtwrCpAfu8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XNtfZmLUPLnPEw4wApXrocURYQaWBR+Q9tDa2OuDwnWiZYUOQgoDX9YnGDzDolV3zAS0/tSU9fnCoyFlfSUfsVuiQJigED71ecIrPiut0SNuAsL9lKPXkoqC5oef0zWB5Gv/OSYxDku6qnT1sPyVIs3gjWeJns0k+z2u5hcYBKw= 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=Ctu1S6bx; arc=none smtp.client-ip=202.108.3.25 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="Ctu1S6bx" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1771762531; bh=AuSLOIUwEnGH2s4eMnx1GRRBlizQTy+UsgFg5LB5kbY=; h=From:Subject:Date:Message-ID; b=Ctu1S6bxwl3lUuBroggxi6OxgQ1K+IppoWRrgYPEXyecyLKouqWpOFALcFz/m+Dmu 0jlBntInWizn9gfKHRRm6ycaE1sWecQ0ls1/rPRudcxKwOoSwtoygO2I3XPoHUKUzk sIu8dgfOii6nxzpEZM71LxrYu/fScwqPIS460J0A= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.62.144]) by sina.com (10.54.253.31) with ESMTP id 699AF35D00004BB8; Sun, 22 Feb 2026 20:15:27 +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: 1748106816222 X-SMAIL-UIID: 0C367D89C3B04989870ED2E44F272C91-20260222-201527-1 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: Sun, 22 Feb 2026 20:15:17 +0800 Message-ID: <20260222121518.3358-1-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 @@ -3072,12 +3072,15 @@ EXPORT_SYMBOL(dvb_register_frontend); int dvb_unregister_frontend(struct dvb_frontend *fe) { struct dvb_frontend_private *fepriv = fe->frontend_priv; + struct dvb_device *dvbdev; dev_dbg(fe->dvb->device, "%s:\n", __func__); mutex_lock(&frontend_mutex); dvb_frontend_stop(fe); - dvb_remove_device(fepriv->dvbdev); + dvbdev = fepriv->dvbdev; + fepriv->dvbdev = NULL; + dvb_unregister_device(dvbdev); /* fe is invalid now */ mutex_unlock(&frontend_mutex); --