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 X-Spam-Level: X-Spam-Status: No, score=-7.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 E4291C43219 for ; Mon, 29 Apr 2019 02:10:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C094520675 for ; Mon, 29 Apr 2019 02:10:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726839AbfD2CKo (ORCPT ); Sun, 28 Apr 2019 22:10:44 -0400 Received: from mx2.suse.de ([195.135.220.15]:51014 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726439AbfD2CKo (ORCPT ); Sun, 28 Apr 2019 22:10:44 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id C9DFDAD05; Mon, 29 Apr 2019 02:10:41 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 0B8711E3C11; Mon, 29 Apr 2019 04:10:40 +0200 (CEST) Date: Mon, 29 Apr 2019 04:10:40 +0200 From: Jan Kara To: syzbot Cc: amir73il@gmail.com, jack@suse.cz, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: general protection fault in fanotify_handle_event Message-ID: <20190429021039.GB29678@quack2.suse.cz> References: <20190426105511.GA18333@quack2.suse.cz> <00000000000089f82105876d041b@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <00000000000089f82105876d041b@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri 26-04-19 04:13:00, syzbot wrote: > Hello, > > syzbot has tested the proposed patch but the reproducer still triggered > crash: > general protection fault in fanotify_handle_event > > kasan: CONFIG_KASAN_INLINE enabled > kasan: GPF could be caused by NULL-ptr deref or user memory access > general protection fault: 0000 [#1] PREEMPT SMP KASAN > CPU: 0 PID: 13565 Comm: syz-executor.2 Not tainted 5.1.0-rc6+ #1 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:fanotify_get_fsid fs/notify/fanotify/fanotify.c:352 [inline] > RIP: 0010:fanotify_handle_event+0x7d0/0xc40 > fs/notify/fanotify/fanotify.c:412 > Code: ff ff 48 8b 18 48 8d 7b 68 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 > 47 04 00 00 48 8b 5b 68 48 8d 7b 3c 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 3a 48 > 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 > RSP: 0018:ffff888085eb7b78 EFLAGS: 00010203 > RAX: 1ffff11013db05ab RBX: 0000000000000000 RCX: ffffffff81c427ae > RDX: 0000000000000007 RSI: ffffffff81c427bb RDI: 000000000000003c > RBP: ffff888085eb7cc0 R08: ffff88808b0926c0 R09: 0000000000000000 > R10: ffff88808b092f90 R11: ffff88808b0926c0 R12: 0000000000000002 > R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000 > FS: 00007ff801b58700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f500e416000 CR3: 00000000a3f17000 CR4: 00000000001406f0 > Call Trace: > send_to_group fs/notify/fsnotify.c:243 [inline] > fsnotify+0x725/0xbc0 fs/notify/fsnotify.c:381 > fsnotify_path include/linux/fsnotify.h:54 [inline] > fsnotify_path include/linux/fsnotify.h:47 [inline] > fsnotify_modify include/linux/fsnotify.h:263 [inline] > vfs_write+0x4dc/0x580 fs/read_write.c:551 > ksys_write+0x14f/0x2d0 fs/read_write.c:599 > __do_sys_write fs/read_write.c:611 [inline] > __se_sys_write fs/read_write.c:608 [inline] > __x64_sys_write+0x73/0xb0 fs/read_write.c:608 > do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x458c29 > Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 > 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff > 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007ff801b57c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 > RDX: 0000000000000007 RSI: 0000000020000080 RDI: 0000000000000005 > RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff801b586d4 > R13: 00000000004c8386 R14: 00000000004de8b8 R15: 00000000ffffffff > Modules linked in: > ---[ end trace 1767f2144c7cb47e ]--- > RIP: 0010:fanotify_get_fsid fs/notify/fanotify/fanotify.c:352 [inline] > RIP: 0010:fanotify_handle_event+0x7d0/0xc40 > fs/notify/fanotify/fanotify.c:412 > Code: ff ff 48 8b 18 48 8d 7b 68 48 89 f8 48 c1 e8 03 42 80 3c 38 00 0f 85 > 47 04 00 00 48 8b 5b 68 48 8d 7b 3c 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 3a 48 > 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 > RSP: 0018:ffff888085eb7b78 EFLAGS: 00010203 > RAX: 1ffff11013db05ab RBX: 0000000000000000 RCX: ffffffff81c427ae > RDX: 0000000000000007 RSI: ffffffff81c427bb RDI: 000000000000003c > RBP: ffff888085eb7cc0 R08: ffff88808b0926c0 R09: 0000000000000000 > R10: ffff88808b092f90 R11: ffff88808b0926c0 R12: 0000000000000002 > R13: 0000000000000000 R14: 0000000000000001 R15: dffffc0000000000 > FS: 00007ff801b58700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007f500e416000 CR3: 00000000a3f17000 CR4: 00000000001406f0 > > > Tested on: > > commit: 8c7008a0 fsnotify: Fix NULL ptr deref in fanotify_get_fsid() > git tree: > git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git fsnotify > console output: https://syzkaller.appspot.com/x/log.txt?x=13020ef4a00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=a42d110b47dd6b36 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) Let's try new version of the patch: #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git fsnotify Honza -- Jan Kara SUSE Labs, CR