syzbot


KCSAN: data-race in __send_signal / futex_wait_queue_me

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 1725d, last: 1685d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __send_signal / futex_wait_queue_me (2) kernel 384 1336d 1669d 0/28 auto-closed as invalid on 2021/07/07 21:48

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __send_signal / futex_wait_queue_me

write to 0xffff888121afb024 of 4 bytes by task 8672 on cpu 1:
 freezer_do_not_count include/linux/freezer.h:109 [inline]
 freezable_schedule include/linux/freezer.h:171 [inline]
 futex_wait_queue_me+0x186/0x250 kernel/futex.c:2634
 futex_wait+0x153/0x3a0 kernel/futex.c:2740
 do_futex+0x144a/0x21b0 kernel/futex.c:3811
 __do_sys_futex kernel/futex.c:3872 [inline]
 __se_sys_futex+0x26d/0x330 kernel/futex.c:3840
 __x64_sys_futex+0x74/0x80 kernel/futex.c:3840
 do_syscall_64+0x71/0x120 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888121afb024 of 4 bytes by task 8659 on cpu 0:
 __send_signal+0x26d/0x7d0 kernel/signal.c:1098
 send_signal+0x398/0x3e0 kernel/signal.c:1241
 do_send_sig_info+0x9b/0xe0 kernel/signal.c:1290
 do_send_specific+0xc7/0x100 kernel/signal.c:3780
 do_tkill kernel/signal.c:3806 [inline]
 __do_sys_tgkill kernel/signal.c:3825 [inline]
 __se_sys_tgkill kernel/signal.c:3819 [inline]
 __x64_sys_tgkill+0x108/0x140 kernel/signal.c:3819
 do_syscall_64+0x71/0x120 arch/x86/entry/common.c:359
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8659 Comm: syz-fuzzer Not tainted 5.8.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/18 14:10 upstream 1b5044021070 3ea11d3f .config console log report ci2-upstream-kcsan-gce
2020/06/16 23:02 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b9f3810b .config console log report ci2-upstream-kcsan-gce
2020/06/16 11:00 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 4ea9d964 .config console log report ci2-upstream-kcsan-gce
2020/06/15 20:17 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 baca2611 .config console log report ci2-upstream-kcsan-gce
2020/06/14 11:13 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2a22c77a .config console log report ci2-upstream-kcsan-gce
2020/06/13 23:14 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a61674a5 .config console log report ci2-upstream-kcsan-gce
2020/06/13 11:18 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 dbce178a .config console log report ci2-upstream-kcsan-gce
2020/06/13 04:45 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f4724dd3 .config console log report ci2-upstream-kcsan-gce
2020/06/12 16:31 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3036d6fd .config console log report ci2-upstream-kcsan-gce
2020/06/11 16:27 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 1beaee21 .config console log report ci2-upstream-kcsan-gce
2020/06/10 00:27 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 860c4de9 .config console log report ci2-upstream-kcsan-gce
2020/06/08 10:56 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 7604bb03 .config console log report ci2-upstream-kcsan-gce
2020/06/07 21:01 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 7751efd0 .config console log report ci2-upstream-kcsan-gce
2020/06/06 13:41 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e6b89e4e .config console log report ci2-upstream-kcsan-gce
2020/06/06 01:29 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c3e9afb3 .config console log report ci2-upstream-kcsan-gce
2020/06/04 13:05 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6720fdef .config console log report ci2-upstream-kcsan-gce
2020/06/02 12:36 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 52fd7b7d .config console log report ci2-upstream-kcsan-gce
2020/05/28 12:35 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c7192a2f .config console log report ci2-upstream-kcsan-gce
2020/05/11 10:01 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f8f57555 .config console log report ci2-upstream-kcsan-gce
2020/05/09 02:14 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e97b06d3 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.