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 0B890C28CF8 for ; Mon, 15 Oct 2018 06:30:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A655D2064E for ; Mon, 15 Oct 2018 06:30:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A655D2064E 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 S1726560AbeJOON4 (ORCPT ); Mon, 15 Oct 2018 10:13:56 -0400 Received: from mail-it1-f198.google.com ([209.85.166.198]:34646 "EHLO mail-it1-f198.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726164AbeJOON4 (ORCPT ); Mon, 15 Oct 2018 10:13:56 -0400 Received: by mail-it1-f198.google.com with SMTP id p20-v6so19264685itg.1 for ; Sun, 14 Oct 2018 23:30:03 -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=yhM0ItOqmIFZFMs0YDHpCLHn4QyzPK5rbyiMwrPTP2A=; b=cPXEli1T3eIaYmZ9VML6CMqJt/rOiTAYvBC9J5e8haudCdvaiMvtizlvdJwGF+DMvQ Y4sTh4/f7nnuYEqTUwPJs+24uoj83OXdfKR8KY2xUQ8j2HYJ64Oa0wui0QA14GOwVsJs ATHecDjaGT4DyQUQY2LnVCSV5WYv/MBIX9jn9Zo8jO3YWqicogZpNi53oXloJyij63EB JhqbOni4t/X0CN6Yf7ZSBtlfZIvfEKAMCHH4oXX1+ztAuni+p+ep/v6Pg65RpnWkMr/3 PQyFjeI5Xq5LjKWa8Z1GSdseNtwMp3CBACAGDInmEmiV5v8MTLwjla1Slpph7fT8gQZu c9bg== X-Gm-Message-State: ABuFfohh1c6+E3lqI4iOkChR6GgnJXTwxEGcmcbRwh1HDkatCwXQdfOv mkhSZFPyQHPUP4XvhgJsC+8rOgYFYYx0brTzlF4Cbo/nwrTH X-Google-Smtp-Source: ACcGV6369kQmZrdqm4VlJRFxnuWLmfzAJUI5vNrh88K13W61ssNt67m2vwy5YHfGJsJcAQqZxGLO9EB4qJAY2aWjurckosGj+gPH MIME-Version: 1.0 X-Received: by 2002:a5e:d710:: with SMTP id v16-v6mr12247741iom.26.1539585003462; Sun, 14 Oct 2018 23:30:03 -0700 (PDT) Date: Sun, 14 Oct 2018 23:30:03 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000003ba80905783e9189@google.com> Subject: KASAN: use-after-free Write in skb_release_data (2) From: syzbot To: davem@davemloft.net, kuznet@ms2.inr.ac.ru, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com, yoshfuji@linux-ipv6.org 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: e40a826a6cbc qed: Add support for virtual link. git tree: net-next console output: https://syzkaller.appspot.com/x/log.txt?x=168954a5400000 kernel config: https://syzkaller.appspot.com/x/.config?x=7e7e2279c0020d5f dashboard link: https://syzkaller.appspot.com/bug?extid=580be3953ed99133804f compiler: gcc (GCC) 8.0.1 20180413 (experimental) Unfortunately, I don't have any reproducer for this crash yet. IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+580be3953ed99133804f@syzkaller.appspotmail.com ================================================================== BUG: KASAN: use-after-free in atomic_sub_return include/asm-generic/atomic-instrumented.h:305 [inline] BUG: KASAN: use-after-free in skb_release_data+0x1a3/0x880 net/core/skbuff.c:559 Write of size 4 at addr ffff8801d8cb4120 by task syz-executor0/8395 CPU: 0 PID: 8395 Comm: syz-executor0 Not tainted 4.19.0-rc6+ #254 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+0x1c4/0x2b4 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 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278 atomic_sub_return include/asm-generic/atomic-instrumented.h:305 [inline] skb_release_data+0x1a3/0x880 net/core/skbuff.c:559 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] kfree_skb+0x1bb/0x580 net/core/skbuff.c:659 sit_tunnel_xmit+0x173/0x30d0 net/ipv6/sit.c:1044 __netdev_start_xmit include/linux/netdevice.h:4328 [inline] netdev_start_xmit include/linux/netdevice.h:4337 [inline] xmit_one net/core/dev.c:3219 [inline] dev_hard_start_xmit+0x295/0xc90 net/core/dev.c:3235 __dev_queue_xmit+0x2f0d/0x3950 net/core/dev.c:3805 dev_queue_xmit+0x17/0x20 net/core/dev.c:3838 packet_sendmsg_spkt+0xf44/0x16f0 net/packet/af_packet.c:1975 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457519 Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2a52d30c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457519 RDX: 0000000000000000 RSI: 00000000200003c0 RDI: 0000000000000003 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2a52d316d4 R13: 00000000004c34d5 R14: 00000000004d52c8 R15: 00000000ffffffff Allocated by task 8395: 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 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x47/0x70 mm/slab.c:3696 __kmalloc_reserve.isra.39+0x41/0xe0 net/core/skbuff.c:137 __alloc_skb+0x155/0x770 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:997 [inline] sock_wmalloc+0x16d/0x1f0 net/core/sock.c:1934 packet_sendmsg_spkt+0x48a/0x16f0 net/packet/af_packet.c:1922 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 8395: 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] kfree+0xcf/0x230 mm/slab.c:3813 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x6a4/0x880 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] consume_skb+0x1ae/0x570 net/core/skbuff.c:701 packet_rcv+0x172/0x1820 net/packet/af_packet.c:2139 dev_queue_xmit_nit+0x8ae/0xb30 net/core/dev.c:2020 xmit_one net/core/dev.c:3215 [inline] dev_hard_start_xmit+0x186/0xc90 net/core/dev.c:3235 __dev_queue_xmit+0x2f0d/0x3950 net/core/dev.c:3805 dev_queue_xmit+0x17/0x20 net/core/dev.c:3838 packet_sendmsg_spkt+0xf44/0x16f0 net/packet/af_packet.c:1975 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:631 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2116 __sys_sendmsg+0x11d/0x280 net/socket.c:2154 __do_sys_sendmsg net/socket.c:2163 [inline] __se_sys_sendmsg net/socket.c:2161 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2161 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 ffff8801d8cb4040 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 224 bytes inside of 512-byte region [ffff8801d8cb4040, ffff8801d8cb4240) The buggy address belongs to the page: page:ffffea0007632d00 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801d8cb42c0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea00070baf08 ffffea000736a788 ffff8801da800940 raw: ffff8801d8cb42c0 ffff8801d8cb4040 0000000100000005 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d8cb4000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801d8cb4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff8801d8cb4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d8cb4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d8cb4200: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ================================================================== --- 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.