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=-3.9 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,HEXHASH_WORD,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 134C8C48BD6 for ; Thu, 27 Jun 2019 03:59:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D986B20665 for ; Thu, 27 Jun 2019 03:59:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727133AbfF0D7G (ORCPT ); Wed, 26 Jun 2019 23:59:06 -0400 Received: from mail-io1-f72.google.com ([209.85.166.72]:42629 "EHLO mail-io1-f72.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726563AbfF0D7G (ORCPT ); Wed, 26 Jun 2019 23:59:06 -0400 Received: by mail-io1-f72.google.com with SMTP id f22so1063780ioj.9 for ; Wed, 26 Jun 2019 20:59:05 -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:in-reply-to:message-id:subject :from:to; bh=8pgHqabBi5mSPkIjY3IFdmWwgOLpGvbNYudJhVT77dg=; b=sZHK3S99nMZ1Tob3JlGGtd3AETGUtBgoD0e5XzH/V1b1vI+EZz28SslNE1HoTXfM4M UDExF2Ym1ZoIvTVauKdV1a3Xv/k3qmrU0CeSetzufRvAHyQnJgxqWsU6RUxH0RaR7j73 GfBKHntbBRw8VQK9CvMdZRHY+2iMZh2FYeY74JjG3LVddts1vNbav0haTGnLx4Jdqn64 UFAYbW8ZnI3sB7sTqEh8PPon5xRlDA8TTqMOB40GeI/s+FH4k2gksgSzmciJpkgAOz/Y gh/Ky5FGg4ZoRx9EGCCR5ey+0kdycYOV6/Y2+tE2Qz+ZniIOnxf1Obqg7DzGkC1wgDcg o4sA== X-Gm-Message-State: APjAAAWYm3teRLHD9Kv/aeIa9NuRm+PU9E5U/SUXv3zVG50A9VLkECN7 gglqCEssGDo5Av+iRzhlaHt8oz1JOcbT688CG+0Nddv9J4LN X-Google-Smtp-Source: APXvYqziDY8uW1NwdQdNbOR/D9XSY1H6HsU13mWuIWA8tK+8q++u1XBbkGq9/dA6tDiBVAmLFu9WscqUoIGbB5bYG3094fYQWbqu MIME-Version: 1.0 X-Received: by 2002:a6b:6409:: with SMTP id t9mr2072174iog.270.1561607945273; Wed, 26 Jun 2019 20:59:05 -0700 (PDT) Date: Wed, 26 Jun 2019 20:59:05 -0700 In-Reply-To: <000000000000d028b30588fed102@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000db481c058c462e4c@google.com> Subject: Re: KASAN: use-after-free Write in xfrm_hash_rebuild From: syzbot To: davem@davemloft.net, herbert@gondor.apana.org.au, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, steffen.klassert@secunet.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org syzbot has found a reproducer for the following crash on: HEAD commit: 249155c2 Merge branch 'parisc-5.2-4' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10f017c3a00000 kernel config: https://syzkaller.appspot.com/x/.config?x=9a31528e58cc12e2 dashboard link: https://syzkaller.appspot.com/bug?extid=0165480d4ef07360eeda compiler: clang version 9.0.0 (/home/glider/llvm/clang 80fee25776c2fb61e74c1ecb1a523375c2500b69) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16cf37c3a00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+0165480d4ef07360eeda@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:221 [inline] BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:748 [inline] BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:455 [inline] BUG: KASAN: use-after-free in xfrm_hash_rebuild+0xa0d/0x1000 net/xfrm/xfrm_policy.c:1318 Write of size 8 at addr ffff888095e79c00 by task kworker/1:3/8066 CPU: 1 PID: 8066 Comm: kworker/1:3 Not tainted 5.2.0-rc6+ #7 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events xfrm_hash_rebuild Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113 print_address_description+0x6d/0x310 mm/kasan/report.c:188 __kasan_report+0x14b/0x1c0 mm/kasan/report.c:317 kasan_report+0x26/0x50 mm/kasan/common.c:614 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:137 __write_once_size include/linux/compiler.h:221 [inline] __hlist_del include/linux/list.h:748 [inline] hlist_del_rcu include/linux/rculist.h:455 [inline] xfrm_hash_rebuild+0xa0d/0x1000 net/xfrm/xfrm_policy.c:1318 process_one_work+0x814/0x1130 kernel/workqueue.c:2269 worker_thread+0xc01/0x1640 kernel/workqueue.c:2415 kthread+0x325/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 8064: save_stack mm/kasan/common.c:71 [inline] set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:489 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503 __do_kmalloc mm/slab.c:3660 [inline] __kmalloc+0x23c/0x310 mm/slab.c:3669 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:742 [inline] xfrm_hash_alloc+0x38/0xe0 net/xfrm/xfrm_hash.c:21 xfrm_policy_init net/xfrm/xfrm_policy.c:4036 [inline] xfrm_net_init+0x269/0xd60 net/xfrm/xfrm_policy.c:4120 ops_init+0x336/0x420 net/core/net_namespace.c:130 setup_net+0x212/0x690 net/core/net_namespace.c:316 copy_net_ns+0x224/0x380 net/core/net_namespace.c:439 create_new_namespaces+0x4ec/0x700 kernel/nsproxy.c:103 unshare_nsproxy_namespaces+0x12a/0x190 kernel/nsproxy.c:202 ksys_unshare+0x540/0xac0 kernel/fork.c:2692 __do_sys_unshare kernel/fork.c:2760 [inline] __se_sys_unshare kernel/fork.c:2758 [inline] __x64_sys_unshare+0x38/0x40 kernel/fork.c:2758 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 17: save_stack mm/kasan/common.c:71 [inline] set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x12a/0x1e0 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kfree+0xae/0x120 mm/slab.c:3755 xfrm_hash_free+0x38/0xd0 net/xfrm/xfrm_hash.c:35 xfrm_bydst_resize net/xfrm/xfrm_policy.c:602 [inline] xfrm_hash_resize+0x13f1/0x1840 net/xfrm/xfrm_policy.c:680 process_one_work+0x814/0x1130 kernel/workqueue.c:2269 worker_thread+0xc01/0x1640 kernel/workqueue.c:2415 kthread+0x325/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff888095e79c00 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of 64-byte region [ffff888095e79c00, ffff888095e79c40) The buggy address belongs to the page: page:ffffea0002579e40 refcount:1 mapcount:0 mapping:ffff8880aa400340 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea0002540888 ffffea0002907548 ffff8880aa400340 raw: 0000000000000000 ffff888095e79000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888095e79b00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ffff888095e79b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc > ffff888095e79c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888095e79c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888095e79d00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc ==================================================================