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KCSAN: data-race in complete_signal / futex_wait_queue_me (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 1818d, last: 1686d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in complete_signal / futex_wait_queue_me (3) kernel 373 1336d 1669d 0/28 auto-closed as invalid on 2021/07/07 04:16
upstream KCSAN: data-race in complete_signal / futex_wait_queue_me kernel 2 1905d 1909d 0/28 closed as invalid on 2019/11/19 14:54

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

write to 0xffff88812b2b5024 of 4 bytes by task 8932 on cpu 0:
 freezer_do_not_count include/linux/freezer.h:109 [inline]
 freezable_schedule include/linux/freezer.h:171 [inline]
 futex_wait_queue_me+0x17d/0x290 kernel/futex.c:2631
 futex_wait+0x17e/0x3a0 kernel/futex.c:2737
 do_futex+0xe2/0x15b0 kernel/futex.c:3808
 __do_sys_futex kernel/futex.c:3869 [inline]
 __se_sys_futex kernel/futex.c:3837 [inline]
 __x64_sys_futex+0x2dc/0x410 kernel/futex.c:3837
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812b2b5024 of 4 bytes by task 8930 on cpu 1:
 wants_signal kernel/signal.c:977 [inline]
 complete_signal+0x85/0x5c0 kernel/signal.c:1000
 __send_signal+0x675/0x8a0 kernel/signal.c:1180
 send_signal+0x211/0x2a0 kernel/signal.c:1241
 do_send_sig_info+0x59/0xc0 kernel/signal.c:1290
 do_send_specific+0xd8/0x100 kernel/signal.c:3780
 do_tkill+0xf8/0x130 kernel/signal.c:3806
 __do_sys_tgkill kernel/signal.c:3825 [inline]
 __se_sys_tgkill kernel/signal.c:3819 [inline]
 __x64_sys_tgkill+0x6d/0x90 kernel/signal.c:3819
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8930 Comm: syz-fuzzer Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/17 11:00 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b6c46f43 .config console log report ci2-upstream-kcsan-gce
2020/06/16 23:09 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b9f3810b .config console log report ci2-upstream-kcsan-gce
2020/06/16 10:56 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 4ea9d964 .config console log report ci2-upstream-kcsan-gce
2020/06/15 08:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8e3ab941 .config console log report ci2-upstream-kcsan-gce
2020/06/12 04:17 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 819b58b0 .config console log report ci2-upstream-kcsan-gce
2020/06/11 00:31 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3ab7a05a .config console log report ci2-upstream-kcsan-gce
2020/06/09 12:40 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 092934c1 .config console log report ci2-upstream-kcsan-gce
2020/06/08 22:41 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 0d60b78a .config console log report ci2-upstream-kcsan-gce
2020/06/08 10:48 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 7604bb03 .config console log report ci2-upstream-kcsan-gce
2020/06/04 13:22 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6720fdef .config console log report ci2-upstream-kcsan-gce
2020/06/04 01:10 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b0d1c0d5 .config console log report ci2-upstream-kcsan-gce
2020/06/03 00:40 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f3ba1b5b .config console log report ci2-upstream-kcsan-gce
2020/05/28 12:58 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c7192a2f .config console log report ci2-upstream-kcsan-gce
2020/05/13 12:50 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 9a6d42fb .config console log report ci2-upstream-kcsan-gce
2020/04/09 04:07 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config console log report ci2-upstream-kcsan-gce
2020/03/13 14:20 https://github.com/google/ktsan.git kcsan 941e0d917bbf fd69032d .config console log report ci2-upstream-kcsan-gce
2020/02/11 02:53 https://github.com/google/ktsan.git kcsan f60f0f543333 d9e55b05 .config console log report ci2-upstream-kcsan-gce
2020/02/06 09:46 https://github.com/google/ktsan.git kcsan 245a43005292 662cf49a .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.