From mboxrd@z Thu Jan 1 00:00:00 1970 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 D6076ECAAA1 for ; Mon, 31 Oct 2022 23:06:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229767AbiJaXGA (ORCPT ); Mon, 31 Oct 2022 19:06:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33676 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229441AbiJaXF6 (ORCPT ); Mon, 31 Oct 2022 19:05:58 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEB0113D36 for ; Mon, 31 Oct 2022 16:05:56 -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 ams.source.kernel.org (Postfix) with ESMTPS id 7DCCDB81AD6 for ; Mon, 31 Oct 2022 23:05:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6783C433D6; Mon, 31 Oct 2022 23:05:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1667257554; bh=h4RA8SJO/1JTmJqF/Aszy+U1QwyKo2oNB8AQeYPq7a0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=VTpXqtF5p9o0aGBKgejOkSqHBFKPKVPRsNUbpLeAOyLCh7Lw+Jly67VdOEQIkCWtV qvNEBcxObsiBomwrvOA0OPgrnQwthP4vNbA14bRBJqhOPXr/TrVxNh37G6/W8k+wSy R1E1muPwCnYq7a7nQ2rQJvhFxLhzBstJxnN9B6T4= Date: Mon, 31 Oct 2022 16:05:53 -0700 From: Andrew Morton To: syzbot Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, syzkaller-bugs@googlegroups.com, Mike Rapoport Subject: Re: [syzbot] general protection fault in mpol_parse_str Message-Id: <20221031160553.5afd9c461ebf34cfdcf70881@linux-foundation.org> In-Reply-To: <00000000000078a84b05ec45e73b@google.com> References: <00000000000078a84b05ec45e73b@google.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 30 Oct 2022 12:57:43 -0700 syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 4d48f589d294 Add linux-next specific files for 20221021 Thanks. > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=165e12da880000 > kernel config: https://syzkaller.appspot.com/x/.config?x=2c4b7d600a5739a6 > dashboard link: https://syzkaller.appspot.com/bug?extid=a7f196a1dbf5e2c70568 > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11f10ff6880000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=145f1ff2880000 does memcpy((void*)0x20000100, "mpol=", 5); syscall(__NR_mount, 0ul, 0x20000040ul, 0x20000080ul, 0ul, 0x20000100ul); so I assume we've fallen afoul of the patch "vfs: parse: deal with zero length string value" (https://lkml.kernel.org/r/166365878918.39016.12757946948158123324.stgit@donald.themaw.net). I have dropped that patch today so hopefully we're all good now. > > ... >