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=1.8 required=3.0 tests=FROM_LOCAL_HEX, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SORTED_RECIPS,SPF_PASS, URIBL_BLOCKED autolearn=no 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 AB6B7C43142 for ; Tue, 31 Jul 2018 12:31:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56A3F20841 for ; Tue, 31 Jul 2018 12:31:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56A3F20841 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 S1732205AbeGaOLK (ORCPT ); Tue, 31 Jul 2018 10:11:10 -0400 Received: from mail-it0-f69.google.com ([209.85.214.69]:54013 "EHLO mail-it0-f69.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732076AbeGaOLK (ORCPT ); Tue, 31 Jul 2018 10:11:10 -0400 Received: by mail-it0-f69.google.com with SMTP id e5-v6so2482347itf.3 for ; Tue, 31 Jul 2018 05:31:03 -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=RgA0n7+hhf++li63OGnXrtYOWG/s4CQk9qBlHjwK68w=; b=V8RfZtniR4Thea7KWBRdUSzVn82CkftNYUVo6TW9f4r+wHTkCL5V3LLy/hGcnTXhmq K6BZ2b1fhcagfDNDAa5LQiDKUjEkZFtR253Ma50EZcBCbcB0tnK52wXzLM7hvosZHQ2+ 5C1K7jkxZ/iSU88A8EbPMnoz5Y9yRTGiQFXBi3hVagudolF8Y3mDdeutsxNyehJE0TpN m460h8mdmlDcyHZYDz/HBMXQ+80FbuxP4zzwV8QREtm61YqCjubdyEju8+xJBDuN2qFu 3RrDibtCn+Odupko0Tb8B6Nj3tV3TWYkdlRaT3O9g9dt2w2aL9NLZp7rg3ZieluO/sH6 CrXw== X-Gm-Message-State: AOUpUlHLkc1be+dECiGZU1I0t7ga1UTy22+c/EGI0/V1hLQjz2Xq+GVh NajAMttjjhgSz6mvuDFDVSTmfvkVRg7853D2we2pHDf7HAqX X-Google-Smtp-Source: AAOMgpc+RZ023/2uduKP3nA1QuhWIxBsjfeN280C8AbU2HWSrE7d3HSS6cb0zMIBYybplQcEI6P/a9SVEC3ZClFBLJpuhz2vpSly MIME-Version: 1.0 X-Received: by 2002:a6b:a303:: with SMTP id m3-v6mr8369402ioe.96.1533040263157; Tue, 31 Jul 2018 05:31:03 -0700 (PDT) Date: Tue, 31 Jul 2018 05:31:03 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <0000000000004fe2be05724ac084@google.com> Subject: KASAN: use-after-free Read in rtnetlink_put_metrics From: syzbot To: christian.brauner@ubuntu.com, davem@davemloft.net, dsahern@gmail.com, fw@strlen.de, jbenc@redhat.com, ktkhai@virtuozzo.com, linux-kernel@vger.kernel.org, lucien.xin@gmail.com, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com 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: 61f4b23769f0 netlink: Don't shift with UB on nlk->ngroups git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=14a9de58400000 kernel config: https://syzkaller.appspot.com/x/.config?x=ffb4428fdc82f93b dashboard link: https://syzkaller.appspot.com/bug?extid=41f9c04b50ef70c66947 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+41f9c04b50ef70c66947@syzkaller.appspotmail.com TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. ================================================================== BUG: KASAN: use-after-free in rtnetlink_put_metrics+0x621/0x690 net/core/rtnetlink.c:754 Read of size 4 at addr ffff8801b3cd8b00 by task udevd/2613 CPU: 0 PID: 2613 Comm: udevd Not tainted 4.18.0-rc6+ #34 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+0x1c9/0x2b4 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432 rtnetlink_put_metrics+0x621/0x690 net/core/rtnetlink.c:754 rt6_fill_node+0x7d9/0x1540 net/ipv6/route.c:4753 inet6_rt_notify+0x161/0x2c0 net/ipv6/route.c:4985 fib6_del_route net/ipv6/ip6_fib.c:1788 [inline] fib6_del+0xf4d/0x1310 net/ipv6/ip6_fib.c:1815 fib6_clean_node+0x3ee/0x5e0 net/ipv6/ip6_fib.c:1976 fib6_walk_continue+0x4b1/0x8e0 net/ipv6/ip6_fib.c:1899 fib6_walk+0x95/0xf0 net/ipv6/ip6_fib.c:1947 fib6_clean_tree+0x1ea/0x360 net/ipv6/ip6_fib.c:2024 __fib6_clean_all+0x21c/0x420 net/ipv6/ip6_fib.c:2040 fib6_clean_all net/ipv6/ip6_fib.c:2051 [inline] fib6_run_gc+0x182/0x3d0 net/ipv6/ip6_fib.c:2107 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2124 call_timer_fn+0x242/0x970 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7a6/0xc70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e8/0xb17 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x1d4/0x210 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:527 [inline] smp_apic_timer_interrupt+0x186/0x730 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:783 [inline] RIP: 0010:qlink_free mm/kasan/quarantine.c:150 [inline] RIP: 0010:qlist_free_all+0xf8/0x160 mm/kasan/quarantine.c:166 Code: c7 40 10 00 00 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 57 b8 a4 ff 48 83 3d 67 b4 37 06 00 74 56 48 89 df 57 9d <0f> 1f 44 00 00 eb af ba 00 00 00 80 48 01 c2 72 43 48 b9 00 00 00 RSP: 0018:ffff8801b54a7b08 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: 0000000000000286 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8801b5498a38 RDI: 0000000000000286 RBP: ffff8801b54a7b40 R08: ffff8801b5498a38 R09: 0000000000000006 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8801dad85dc0 R14: ffff8801b37ace00 R15: ffffffff87f1b0a0 quarantine_reduce+0x163/0x1a0 mm/kasan/quarantine.c:259 kasan_kmalloc+0x99/0xe0 mm/kasan/kasan.c:538 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 slab_post_alloc_hook mm/slab.h:444 [inline] slab_alloc mm/slab.c:3392 [inline] kmem_cache_alloc+0x11b/0x760 mm/slab.c:3552 getname_flags+0xd0/0x5a0 fs/namei.c:140 user_path_at_empty+0x2d/0x50 fs/namei.c:2584 do_readlinkat+0x14b/0x400 fs/stat.c:394 __do_sys_readlink fs/stat.c:427 [inline] __se_sys_readlink fs/stat.c:424 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:424 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7efd8271b577 Code: f0 ff ff 77 02 f3 c3 48 8b 15 bd 38 2b 00 f7 d8 64 89 02 83 c8 ff c3 90 90 90 90 90 90 90 90 90 90 90 90 b8 59 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 38 2b 00 31 d2 48 29 c2 64 RSP: 002b:00007ffe27d23688 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00000000021de250 RCX: 00007efd8271b577 RDX: 0000000000000400 RSI: 00007ffe27d23690 RDI: 00007ffe27d23b70 RBP: 00007ffe27d243b0 R08: 00007ffe27d243b0 R09: 00007efd8276fdc0 R10: 7665642f7379732f R11: 0000000000000246 R12: 00007ffe27d23b70 R13: 0000000000000400 R14: 00000000021de250 R15: 00000000021e3e10 Allocated by task 8953: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x780 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] fib6_metric_set+0x163/0x2c0 net/ipv6/ip6_fib.c:645 fib6_add_rt2node+0xe36/0x27f0 net/ipv6/ip6_fib.c:1000 fib6_add+0xaae/0x14d0 net/ipv6/ip6_fib.c:1308 __ip6_ins_rt+0x54/0x80 net/ipv6/route.c:1163 ip6_route_add+0x6d/0xc0 net/ipv6/route.c:3171 addrconf_prefix_route.isra.48+0x51d/0x720 net/ipv6/addrconf.c:2347 inet6_addr_modify net/ipv6/addrconf.c:4627 [inline] inet6_rtm_newaddr+0x112e/0x1b50 net/ipv6/addrconf.c:4743 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4665 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2453 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4683 netlink_unicast_kernel net/netlink/af_netlink.c:1315 [inline] netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1341 netlink_sendmsg+0xa18/0xfd0 net/netlink/af_netlink.c:1906 sock_sendmsg_nosec net/socket.c:642 [inline] sock_sendmsg+0xd5/0x120 net/socket.c:652 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2126 __sys_sendmsg+0x11d/0x290 net/socket.c:2164 __do_sys_sendmsg net/socket.c:2173 [inline] __se_sys_sendmsg net/socket.c:2171 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2171 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 2613: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xd9/0x260 mm/slab.c:3813 fib6_metrics_release+0x77/0x90 net/ipv6/ip6_fib.c:179 fib6_drop_pcpu_from net/ipv6/ip6_fib.c:899 [inline] fib6_purge_rt+0x5ec/0x7f0 net/ipv6/ip6_fib.c:934 fib6_del_route net/ipv6/ip6_fib.c:1784 [inline] fib6_del+0xc11/0x1310 net/ipv6/ip6_fib.c:1815 fib6_clean_node+0x3ee/0x5e0 net/ipv6/ip6_fib.c:1976 fib6_walk_continue+0x4b1/0x8e0 net/ipv6/ip6_fib.c:1899 fib6_walk+0x95/0xf0 net/ipv6/ip6_fib.c:1947 fib6_clean_tree+0x1ea/0x360 net/ipv6/ip6_fib.c:2024 __fib6_clean_all+0x21c/0x420 net/ipv6/ip6_fib.c:2040 fib6_clean_all net/ipv6/ip6_fib.c:2051 [inline] fib6_run_gc+0x182/0x3d0 net/ipv6/ip6_fib.c:2107 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2124 call_timer_fn+0x242/0x970 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7a6/0xc70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e8/0xb17 kernel/softirq.c:292 The buggy address belongs to the object at ffff8801b3cd8b00 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of 96-byte region [ffff8801b3cd8b00, ffff8801b3cd8b60) The buggy address belongs to the page: page:ffffea0006cf3600 count:1 mapcount:0 mapping:ffff8801dac004c0 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0006a6f3c8 ffffea0007018608 ffff8801dac004c0 raw: 0000000000000000 ffff8801b3cd8000 0000000100000020 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801b3cd8a00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8801b3cd8a80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc > ffff8801b3cd8b00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ^ ffff8801b3cd8b80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8801b3cd8c00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ================================================================== --- This bug is generated by a bot. 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