syzbot


KMSAN: uninit-value in memcmp (2)

Status: fixed on 2018/09/23 19:44
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+d3402c47f680ff24b29c@syzkaller.appspotmail.com
Fix commit: 77d36398d99f net: fix uninit-value in __hw_addr_add_ex()
First crash: 2177d, last: 2051d
Discussions (3)
Title Replies (including bot) Last reply
[PATCH] net: arp, ipv6: handle special case of tap device 7 (7) 2018/10/04 09:53
Re: KMSAN: uninit-value in memcmp (2) 6 (6) 2018/09/27 11:20
KMSAN: uninit-value in memcmp (2) 0 (1) 2018/09/21 21:14
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in memcmp net C 30 2180d 2209d 5/26 fixed on 2018/05/08 18:30

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+0x119/0x180 lib/string.c:861
CPU: 0 PID: 38 Comm: kworker/0:1 Not tainted 4.17.0-rc3+ #88
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+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 memcmp+0x119/0x180 lib/string.c:861
 __hw_addr_add_ex net/core/dev_addr_lists.c:61 [inline]
 __dev_mc_add+0x1fc/0x900 net/core/dev_addr_lists.c:670
 dev_mc_add+0x6d/0x80 net/core/dev_addr_lists.c:687
 igmp6_group_added+0x2db/0xa00 net/ipv6/mcast.c:662
 ipv6_dev_mc_inc+0xe9e/0x1130 net/ipv6/mcast.c:914
 addrconf_join_solict net/ipv6/addrconf.c:2103 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:3853 [inline]
 addrconf_dad_work+0x462/0x2a20 net/ipv6/addrconf.c:3979
 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2145
 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2279
 kthread+0x539/0x720 kernel/kthread.c:239
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:412

Local variable description: ----buf@igmp6_group_added
Variable was created at:
 igmp6_group_added+0x4a/0xa00 net/ipv6/mcast.c:650
 ipv6_dev_mc_inc+0xe9e/0x1130 net/ipv6/mcast.c:914
==================================================================

Crashes (131):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/05/09 18:55 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report syz C ci-upstream-kmsan-gce
2018/09/12 21:00 https://github.com/google/kmsan.git master c795108d2d1c 71907daf .config console log report ci-upstream-kmsan-gce
2018/09/11 20:50 https://github.com/google/kmsan.git master 401f0ab26c43 4ae17b1f .config console log report ci-upstream-kmsan-gce
2018/09/07 03:30 https://github.com/google/kmsan.git master 43e4752ae5dc e30d3b52 .config console log report ci-upstream-kmsan-gce
2018/09/06 15:04 https://github.com/google/kmsan.git master 43e4752ae5dc 0bb7a7eb .config console log report ci-upstream-kmsan-gce
2018/09/06 12:51 https://github.com/google/kmsan.git master 43e4752ae5dc 0bb7a7eb .config console log report ci-upstream-kmsan-gce
2018/09/06 04:30 https://github.com/google/kmsan.git master 43e4752ae5dc 873745f2 .config console log report ci-upstream-kmsan-gce
2018/09/04 15:17 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/04 15:12 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/03 16:23 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/03 12:15 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/03 00:01 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/02 12:02 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/02 07:20 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/01 05:38 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/09/01 03:07 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/08/31 20:44 https://github.com/google/kmsan.git master 28f0ca98eadf a4718693 .config console log report ci-upstream-kmsan-gce
2018/08/31 06:14 https://github.com/google/kmsan.git master ab98bd30a4ba a4718693 .config console log report ci-upstream-kmsan-gce
2018/08/30 10:12 https://github.com/google/kmsan.git master 2dca2cbde67a 6c7e9d3d .config console log report ci-upstream-kmsan-gce
2018/08/30 04:41 https://github.com/google/kmsan.git master 2dca2cbde67a 6c7e9d3d .config console log report ci-upstream-kmsan-gce
2018/08/29 11:31 https://github.com/google/kmsan.git master 2dca2cbde67a 53ff8784 .config console log report ci-upstream-kmsan-gce
2018/08/28 23:38 https://github.com/google/kmsan.git master 2dca2cbde67a b771b17e .config console log report ci-upstream-kmsan-gce
2018/08/28 20:59 https://github.com/google/kmsan.git master 2dca2cbde67a b771b17e .config console log report ci-upstream-kmsan-gce
2018/08/28 18:39 https://github.com/google/kmsan.git master 2dca2cbde67a b771b17e .config console log report ci-upstream-kmsan-gce
2018/08/28 12:47 https://github.com/google/kmsan.git master 72cde92031e1 7ef1de9e .config console log report ci-upstream-kmsan-gce
2018/08/27 04:08 https://github.com/google/kmsan.git master 0cc51dc9a291 758cd203 .config console log report ci-upstream-kmsan-gce
2018/08/26 08:14 https://github.com/google/kmsan.git master 0cc51dc9a291 758cd203 .config console log report ci-upstream-kmsan-gce
2018/08/26 07:09 https://github.com/google/kmsan.git master 0cc51dc9a291 758cd203 .config console log report ci-upstream-kmsan-gce
2018/08/25 07:05 https://github.com/google/kmsan.git master 0cc51dc9a291 9be5aa1d .config console log report ci-upstream-kmsan-gce
2018/08/24 05:40 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/08/23 18:52 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/08/23 02:48 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/08/22 20:05 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/08/21 19:43 https://github.com/google/kmsan.git master 0cc51dc9a291 95b5c82b .config console log report ci-upstream-kmsan-gce
2018/08/20 01:58 https://github.com/google/kmsan.git master 0cc51dc9a291 2dc4378f .config console log report ci-upstream-kmsan-gce
2018/08/19 23:03 https://github.com/google/kmsan.git master 0cc51dc9a291 2dc4378f .config console log report ci-upstream-kmsan-gce
2018/08/19 12:29 https://github.com/google/kmsan.git master 0cc51dc9a291 2dc4378f .config console log report ci-upstream-kmsan-gce
2018/08/18 21:03 https://github.com/google/kmsan.git master 0cc51dc9a291 de20bcbb .config console log report ci-upstream-kmsan-gce
2018/08/18 08:02 https://github.com/google/kmsan.git master 0cc51dc9a291 db1858f6 .config console log report ci-upstream-kmsan-gce
2018/08/17 22:18 https://github.com/google/kmsan.git master 0cc51dc9a291 738da825 .config console log report ci-upstream-kmsan-gce
2018/08/17 09:47 https://github.com/google/kmsan.git master 0cc51dc9a291 9ccc1d45 .config console log report ci-upstream-kmsan-gce
2018/05/09 17:03 https://github.com/google/kmsan.git master 74ee2200b89f 12c7428a .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.