syzbot


KMSAN: uninit-value in __dev_mc_add

Status: fixed on 2021/11/10 00:50
Reported-by: syzbot+001516d86dbe88862cec@syzkaller.appspotmail.com
Fix commit: cca8ea3b05c9 net: tun: set tun->dev->addr_len during TUNSETLINK processing
First crash: 1462d, last: 1265d
Patch testing requests:
Created Duration User Patch Repo Result
2021/04/05 00:22 17m phil@philpotter.co.uk patch https://github.com/google/kmsan.git master OK
2021/04/01 21:25 24m phil@philpotter.co.uk patch https://github.com/google/kmsan.git master OK
2021/04/01 20:37 26m phil@philpotter.co.uk patch https://github.com/google/kmsan.git master report log
2021/04/01 17:03 25m phil@philpotter.co.uk patch https://github.com/google/kmsan.git master report log
2020/09/12 20:51 10m anant.thazhemadam@gmail.com patch https://github.com/google/kmsan.git master report log
2020/09/12 20:28 10m anant.thazhemadam@gmail.com patch https://github.com/google/kmsan.git master report log
2020/09/12 13:40 11m anant.thazhemadam@gmail.com https://github.com/google/kmsan.git master report log

Sample crash report:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
IPVS: ftp: loaded support on port[0] = 21
==================================================================
BUG: KMSAN: uninit-value in memcmp+0x117/0x180 lib/string.c:863
CPU: 1 PID: 18 Comm: kworker/1:0 Not tainted 4.19.0-rc4+ #64
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x306/0x460 lib/dump_stack.c:113
 kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917
 __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500
 memcmp+0x117/0x180 lib/string.c:863
 __hw_addr_add_ex net/core/dev_addr_lists.c:61 [inline]
 __dev_mc_add+0x1f9/0x8b0 net/core/dev_addr_lists.c:670
 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687
 igmp6_group_added+0x2d7/0xab0 net/ipv6/mcast.c:676
 __ipv6_dev_mc_inc+0xeff/0x10f0 net/ipv6/mcast.c:934
 ipv6_dev_mc_inc+0x70/0x80 net/ipv6/mcast.c:941
 addrconf_join_solict net/ipv6/addrconf.c:2098 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:3879 [inline]
 addrconf_dad_work+0x3e7/0x2690 net/ipv6/addrconf.c:4006
 process_one_work+0x19c4/0x24f0 kernel/workqueue.c:2153
 worker_thread+0x206d/0x2b30 kernel/workqueue.c:2296
 kthread+0x59c/0x5d0 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:416

Local variable description: ----buf@igmp6_group_added
Variable was created at:
 igmp6_group_added+0x57/0xab0 net/ipv6/mcast.c:664
 __ipv6_dev_mc_inc+0xeff/0x10f0 net/ipv6/mcast.c:934
==================================================================

Crashes (213):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kmsan-gce 2018/10/08 13:05 https://github.com/google/kmsan.git master 43c85fe5a0ee 8b311eaf .config log report syz C
ci-upstream-kmsan-gce 2019/04/10 21:36 https://github.com/google/kmsan.git master 199a02db1f61 e955ac50 .config log report
ci-upstream-kmsan-gce 2019/04/07 15:52 https://github.com/google/kmsan.git master 46200eb9666d c34fde03 .config log report
ci-upstream-kmsan-gce 2019/04/05 01:44 https://github.com/google/kmsan.git master 46200eb9666d e5d1b3ac .config log report
ci-upstream-kmsan-gce 2019/04/02 22:31 https://github.com/google/kmsan.git master 088c01ea0855 dfd3394d .config log report
ci-upstream-kmsan-gce 2019/03/27 11:16 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/27 09:18 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/27 06:58 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/26 13:50 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/26 02:53 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/26 01:11 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/26 00:57 https://github.com/google/kmsan.git master 3c26d882e695 55684ce1 .config log report
ci-upstream-kmsan-gce 2019/03/25 17:41 https://github.com/google/kmsan.git master c10a026b8dee 2c86e0a5 .config log report
ci-upstream-kmsan-gce 2019/03/24 22:17 https://github.com/google/kmsan.git master c10a026b8dee acbc5b7d .config log report
ci-upstream-kmsan-gce 2019/03/24 02:33 https://github.com/google/kmsan.git master c10a026b8dee a2cef203 .config log report
ci-upstream-kmsan-gce 2019/03/24 00:25 https://github.com/google/kmsan.git master c10a026b8dee a2cef203 .config log report
ci-upstream-kmsan-gce 2019/03/23 04:10 https://github.com/google/kmsan.git master c10a026b8dee 3361bde5 .config log report
ci-upstream-kmsan-gce 2019/03/21 19:57 https://github.com/google/kmsan.git master c10a026b8dee dce6e62f .config log report
ci-upstream-kmsan-gce 2019/03/19 19:06 https://github.com/google/kmsan.git master 43cfd3b1484f e4549234 .config log report
ci-upstream-kmsan-gce 2019/03/18 16:56 https://github.com/google/kmsan.git master 43cfd3b1484f 4656beca .config log report
ci-upstream-kmsan-gce 2019/03/17 15:46 https://github.com/google/kmsan.git master 43cfd3b1484f ba18afea .config log report
ci-upstream-kmsan-gce 2019/03/17 06:41 https://github.com/google/kmsan.git master 43cfd3b1484f bab43553 .config log report
ci-upstream-kmsan-gce 2019/03/15 16:37 https://github.com/google/kmsan.git master 63fd07faa48c bab43553 .config log report
ci-upstream-kmsan-gce 2019/03/15 01:23 https://github.com/google/kmsan.git master 9536b452bf7b d72db19b .config log report
ci-upstream-kmsan-gce 2019/03/14 21:36 https://github.com/google/kmsan.git master 9536b452bf7b d72db19b .config log report
ci-upstream-kmsan-gce 2019/03/14 09:49 https://github.com/google/kmsan.git master c530a275757b d09a902e .config log report
ci-upstream-kmsan-gce 2019/03/12 23:25 https://github.com/google/kmsan.git master a695dc5e929e a71bfb62 .config log report
ci-upstream-kmsan-gce 2019/03/11 23:01 https://github.com/google/kmsan.git master a695dc5e929e 12365b99 .config log report
ci-upstream-kmsan-gce 2019/03/11 10:41 https://github.com/google/kmsan.git master a695dc5e929e 12365b99 .config log report
ci-upstream-kmsan-gce 2019/03/10 10:53 https://github.com/google/kmsan.git master a695dc5e929e 12365b99 .config log report
ci-upstream-kmsan-gce 2019/03/08 09:58 https://github.com/google/kmsan.git master a695dc5e929e 12365b99 .config log report
ci-upstream-kmsan-gce 2019/03/07 22:07 https://github.com/google/kmsan.git master a695dc5e929e 4b69c3cb .config log report
ci-upstream-kmsan-gce 2019/03/07 14:09 https://github.com/google/kmsan.git master a695dc5e929e 8c085c5e .config log report
ci-upstream-kmsan-gce 2019/03/04 22:39 https://github.com/google/kmsan.git master fa1981bee40f 7c693b52 .config log report
ci-upstream-kmsan-gce 2019/03/01 19:07 https://github.com/google/kmsan.git master fa1981bee40f 68d9e495 .config log report
ci-upstream-kmsan-gce 2019/03/01 14:47 https://github.com/google/kmsan.git master fa1981bee40f 8a4b3a6b .config log report
ci-upstream-kmsan-gce 2019/03/01 10:02 https://github.com/google/kmsan.git master fa1981bee40f 8a4b3a6b .config log report
ci-upstream-kmsan-gce 2019/02/28 14:47 https://github.com/google/kmsan.git master fa1981bee40f 09aeeba4 .config log report
ci-upstream-kmsan-gce 2019/02/27 07:02 https://github.com/google/kmsan.git master fa1981bee40f f2468c12 .config log report
ci-upstream-kmsan-gce 2019/02/22 08:04 https://github.com/google/kmsan.git master fa1981bee40f 7ff74a98 .config log report
ci-upstream-kmsan-gce 2019/02/21 11:53 https://github.com/google/kmsan.git master fa1981bee40f 3133098b .config log report
ci-upstream-kmsan-gce 2019/02/21 11:52 https://github.com/google/kmsan.git master fa1981bee40f 3133098b .config log report
ci-upstream-kmsan-gce 2019/02/21 06:54 https://github.com/google/kmsan.git master fa1981bee40f c95f0707 .config log report
ci-upstream-kmsan-gce 2019/02/19 11:15 https://github.com/google/kmsan.git master fa1981bee40f 59f36113 .config log report
ci-upstream-kmsan-gce 2019/02/16 20:47 https://github.com/google/kmsan.git master fa1981bee40f f42dee6d .config log report
ci-upstream-kmsan-gce 2019/02/16 14:01 https://github.com/google/kmsan.git master fa1981bee40f f42dee6d .config log report
ci-upstream-kmsan-gce 2019/02/15 23:48 https://github.com/google/kmsan.git master fa1981bee40f f42dee6d .config log report
ci-upstream-kmsan-gce 2019/02/15 20:34 https://github.com/google/kmsan.git master fa1981bee40f f6f233c0 .config log report
ci-upstream-kmsan-gce 2019/02/14 21:14 https://github.com/google/kmsan.git master fa1981bee40f 76dd003f .config log report
ci-upstream-kmsan-gce 2019/02/14 07:25 https://github.com/google/kmsan.git master fa1981bee40f 6a46f448 .config log report
ci-upstream-kmsan-gce 2019/02/13 17:58 https://github.com/google/kmsan.git master fa1981bee40f 0a49c954 .config log report
ci-upstream-kmsan-gce 2018/09/25 18:49 https://github.com/google/kmsan.git master eb2e67596de2 b7e11289 .config log report
* Struck through repros no longer work on HEAD.