KMSAN: uninit-value in memcmp

Status: fixed on 2018/05/08 18:30
Subsystems: net
[Documentation on labels]
Fix commit: 77d36398d99f net: fix uninit-value in __hw_addr_add_ex()
First crash: 3059d, last: 3030d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in memcmp (2) net 7 syz, C 131 2901d 2892d 10/29 fixed on 2018/09/23 19:44

Sample crash report:
==================================================================
BUG: KMSAN: uninit-value in memcmp+0x119/0x180 lib/string.c:861
CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.16.0+ #82
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:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 memcmp+0x119/0x180 lib/string.c:861
 __hw_addr_add_ex net/core/dev_addr_lists.c:60 [inline]
 __dev_mc_add+0x1c2/0x8e0 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:2078 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:3828 [inline]
 addrconf_dad_work+0x427/0x2150 net/ipv6/addrconf.c:3954
 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2113
 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2247
 kthread+0x539/0x720 kernel/kthread.c:239
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:406

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
==================================================================
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3 Comm: kworker/0:0 Tainted: G    B            4.16.0+ #82
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:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 panic+0x39d/0x940 kernel/panic.c:183
 kmsan_report+0x238/0x240 mm/kmsan/kmsan.c:1083
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 memcmp+0x119/0x180 lib/string.c:861
 __hw_addr_add_ex net/core/dev_addr_lists.c:60 [inline]
 __dev_mc_add+0x1c2/0x8e0 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:2078 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:3828 [inline]
 addrconf_dad_work+0x427/0x2150 net/ipv6/addrconf.c:3954
 process_one_work+0x12c6/0x1f60 kernel/workqueue.c:2113
 worker_thread+0x113c/0x24f0 kernel/workqueue.c:2247
 kthread+0x539/0x720 kernel/kthread.c:239
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:406
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (30):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/07 14:17 https://github.com/google/kmsan.git master e2ab7e8abba4 66f22a7f .config console log report syz C ci-upstream-kmsan-gce
2018/05/06 21:04 https://github.com/google/kmsan.git master d2d741e5d189 6c18ddb0 .config console log report ci-upstream-kmsan-gce
2018/05/06 03:29 https://github.com/google/kmsan.git master d2d741e5d189 78b251cb .config console log report ci-upstream-kmsan-gce
2018/05/03 01:32 https://github.com/google/kmsan.git master d2d741e5d189 d5b114b4 .config console log report ci-upstream-kmsan-gce
2018/05/01 17:34 https://github.com/google/kmsan.git master d2d741e5d189 d5b114b4 .config console log report ci-upstream-kmsan-gce
2018/04/30 22:17 https://github.com/google/kmsan.git master d2d741e5d189 d5b114b4 .config console log report ci-upstream-kmsan-gce
2018/04/28 06:08 https://github.com/google/kmsan.git master d2d741e5d189 d5a5d045 .config console log report ci-upstream-kmsan-gce
2018/04/28 00:14 https://github.com/google/kmsan.git master d2d741e5d189 7785e404 .config console log report ci-upstream-kmsan-gce
2018/04/27 21:43 https://github.com/google/kmsan.git master d2d741e5d189 7785e404 .config console log report ci-upstream-kmsan-gce
2018/04/27 21:05 https://github.com/google/kmsan.git master d2d741e5d189 7785e404 .config console log report ci-upstream-kmsan-gce
2018/04/25 19:40 https://github.com/google/kmsan.git master d2d741e5d189 73417389 .config console log report ci-upstream-kmsan-gce
2018/04/23 05:32 https://github.com/google/kmsan.git master d2d741e5d189 d23fcf6c .config console log report ci-upstream-kmsan-gce
2018/04/21 04:01 https://github.com/google/kmsan.git master 48c6a2b0ab1b ca03d688 .config console log report ci-upstream-kmsan-gce
2018/04/20 19:52 https://github.com/google/kmsan.git master 48c6a2b0ab1b cc402841 .config console log report ci-upstream-kmsan-gce
2018/04/20 19:10 https://github.com/google/kmsan.git master 48c6a2b0ab1b cc402841 .config console log report ci-upstream-kmsan-gce
2018/04/20 17:39 https://github.com/google/kmsan.git master 48c6a2b0ab1b cc402841 .config console log report ci-upstream-kmsan-gce
2018/04/18 13:05 https://github.com/google/kmsan.git master 48c6a2b0ab1b 52643b44 .config console log report ci-upstream-kmsan-gce
2018/04/18 04:25 https://github.com/google/kmsan.git master 48c6a2b0ab1b b80fd3b5 .config console log report ci-upstream-kmsan-gce
2018/04/17 17:26 https://github.com/google/kmsan.git master 48c6a2b0ab1b b80fd3b5 .config console log report ci-upstream-kmsan-gce
2018/04/16 18:04 https://github.com/google/kmsan.git master 48c6a2b0ab1b 802ac912 .config console log report ci-upstream-kmsan-gce
2018/04/13 21:20 https://github.com/google/kmsan.git master 35ff515e4bda 7a67784c .config console log report ci-upstream-kmsan-gce
2018/04/12 13:43 https://github.com/google/kmsan.git master 35ff515e4bda 9cd56d71 .config console log report ci-upstream-kmsan-gce
2018/04/11 07:23 https://github.com/google/kmsan.git master 35ff515e4bda 8b8de427 .config console log report ci-upstream-kmsan-gce
2018/04/10 18:52 https://github.com/google/kmsan.git master 35ff515e4bda 8b8de427 .config console log report ci-upstream-kmsan-gce
2018/04/07 13:03 https://github.com/google/kmsan.git master e2ab7e8abba4 66f22a7f .config console log report ci-upstream-kmsan-gce
2018/04/07 06:37 https://github.com/google/kmsan.git master e2ab7e8abba4 d613535f .config console log report ci-upstream-kmsan-gce
2018/04/07 06:36 https://github.com/google/kmsan.git master e2ab7e8abba4 d613535f .config console log report ci-upstream-kmsan-gce
2018/04/07 06:06 https://github.com/google/kmsan.git master e2ab7e8abba4 d613535f .config console log report ci-upstream-kmsan-gce
2018/04/07 05:15 https://github.com/google/kmsan.git master e2ab7e8abba4 d613535f .config console log report ci-upstream-kmsan-gce
2018/04/07 03:15 https://github.com/google/kmsan.git master e2ab7e8abba4 d613535f .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.