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=-0.4 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 BB0B3C4646A for ; Wed, 12 Sep 2018 13:23:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5DFBB206B6 for ; Wed, 12 Sep 2018 13:23:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5DFBB206B6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726860AbeILS1c (ORCPT ); Wed, 12 Sep 2018 14:27:32 -0400 Received: from mail-it0-f69.google.com ([209.85.214.69]:43334 "EHLO mail-it0-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726606AbeILS1c (ORCPT ); Wed, 12 Sep 2018 14:27:32 -0400 Received: by mail-it0-f69.google.com with SMTP id z72-v6so3349051itc.8 for ; Wed, 12 Sep 2018 06:23:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to; bh=3Y+96eAc+F0eFbeI5+gMKc3tMC9TzJ/lthfgPFye9gk=; b=nR+K2z3jQbf9bZRzaM0XCvkS4P45DGkbsd84cdpvBMV15nZJZDs+8qaexCtSdX2B9P hw0LeoJoRuIjJEaJ20J29Mb0UcrU3vm8W8IVHCE0Yd1xitIes5k5EEQwR8zCZyA77bhl eC6mbp/immvivzeRxg2hqZRXmte9CGx2UDqHURxb2Fb/K40t75QnjViHLLSOGHPgjNQ2 eZs6wyHFRg8+2h7cQkD0HQTOR61ATS9gio8sqpoT9jZEReYjgweBiC5eHq/uFiTl0D5L ZeYRoTKQPGcv0OwGyGWJccSPvcuRFESKYe+vn2yQ/I/loKudREoll1u+S048DJqRNg6j 2qJQ== X-Gm-Message-State: APzg51CuWB6kex+1LbP/Aj7ItFI+pwLTMPcuYQ7pBDFjsSaR1XsN3AiD iXVamHlWQQyiAct4ECKTDJe6fYbujC8kNyx3S+I83o0L8WRB X-Google-Smtp-Source: ANB0VdYndwrvKS8oYavUNoUh6D+wnPkUMJz4o7GcPTUuZYei0nDieLLsWyu1aEuo2QZ616OKWgPEGWOsgpNafiIkUB3KvnJcwGFv MIME-Version: 1.0 X-Received: by 2002:a5e:d908:: with SMTP id n8-v6mr1480154iop.77.1536758582661; Wed, 12 Sep 2018 06:23:02 -0700 (PDT) Date: Wed, 12 Sep 2018 06:23:02 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000006cd9da0575ac7d9d@google.com> Subject: KASAN: use-after-free Read in mqueue_get_tree From: syzbot To: arnd@arndb.de, dbueso@suse.de, dhowells@redhat.com, ebiederm@xmission.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, syzbot found the following crash on: HEAD commit: 7c1b097f27bf Add linux-next specific files for 20180912 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=14e6101a400000 kernel config: https://syzkaller.appspot.com/x/.config?x=5980033172920ec0 dashboard link: https://syzkaller.appspot.com/bug?extid=fef0b74a3bf760a9ee85 compiler: gcc (GCC) 8.0.1 20180413 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13104f71400000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+fef0b74a3bf760a9ee85@syzkaller.appspotmail.com random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: cc1: uninitialized urandom read (8 bytes read) ================================================================== BUG: KASAN: use-after-free in mqueue_get_tree+0x2ac/0x2e0 ipc/mqueue.c:362 Read of size 8 at addr ffff8801d7cc0688 by task syz-executor4/5584 CPU: 0 PID: 5584 Comm: syz-executor4 Not tainted 4.19.0-rc3-next-20180912+ #72 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d3/0x2c4 lib/dump_stack.c:113 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 mqueue_get_tree+0x2ac/0x2e0 ipc/mqueue.c:362 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1787 mq_create_mount+0xe3/0x190 ipc/mqueue.c:415 mq_init_ns+0x15a/0x210 ipc/mqueue.c:1621 create_ipc_ns ipc/namespace.c:58 [inline] copy_ipcs+0x3d2/0x580 ipc/namespace.c:84 create_new_namespaces+0x376/0x900 kernel/nsproxy.c:87 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x79c/0x10b0 kernel/fork.c:2535 __do_sys_unshare kernel/fork.c:2603 [inline] __se_sys_unshare kernel/fork.c:2601 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2601 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x459d87 Code: 00 00 00 b8 63 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 3d 8a fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 10 01 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 1d 8a fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffddc9e7fb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459d87 RDX: 0000000000000000 RSI: 00007ffddc9e7fc0 RDI: 0000000008000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000018 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000412c30 R13: 0000000000412cc0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3455: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x730 mm/slab.c:3554 getname_flags+0xd0/0x5a0 fs/namei.c:140 getname fs/namei.c:211 [inline] do_symlinkat+0x8b/0x2d0 fs/namei.c:4143 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3455: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x83/0x290 mm/slab.c:3756 putname+0xf2/0x130 fs/namei.c:261 do_symlinkat+0x18c/0x2d0 fs/namei.c:4161 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801d7cc0540 which belongs to the cache names_cache of size 4096 The buggy address is located 328 bytes inside of 4096-byte region [ffff8801d7cc0540, ffff8801d7cc1540) The buggy address belongs to the page: page:ffffea00075f3000 count:1 mapcount:0 mapping:ffff8801da972d80 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffffea00075fa788 ffffea00075f0b08 ffff8801da972d80 raw: 0000000000000000 ffff8801d7cc0540 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d7cc0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d7cc0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801d7cc0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d7cc0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d7cc0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This bug is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this bug report. See: https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with syzbot. syzbot can test patches for this bug, for details see: https://goo.gl/tpsmEJ#testing-patches