KCSAN: data-race in exit_signals / find_alive_thread (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 2460d, last: 2274d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in exit_signals / find_alive_thread kernel 6 7 2469d 2487d 0/29 closed as invalid on 2019/11/19 15:04

Sample crash report:
==================================================================
BUG: KCSAN: data-race in exit_signals / find_alive_thread

write to 0xffff8880b01100a4 of 4 bytes by task 13987 on cpu 1:
 exit_signals+0x135/0x4c0 kernel/signal.c:2827
 do_exit+0x17b/0x11e0 kernel/exit.c:744
 do_group_exit+0xae/0x1a0 kernel/exit.c:893
 __do_sys_exit_group kernel/exit.c:904 [inline]
 __se_sys_exit_group kernel/exit.c:902 [inline]
 __x64_sys_exit_group+0x2b/0x30 kernel/exit.c:902
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880b01100a4 of 4 bytes by task 13988 on cpu 0:
 find_alive_thread+0xd5/0x120 kernel/exit.c:489
 find_new_reaper kernel/exit.c:538 [inline]
 forget_original_parent+0xef/0x980 kernel/exit.c:613
 exit_notify kernel/exit.c:646 [inline]
 do_exit+0x75c/0x11e0 kernel/exit.c:816
 do_group_exit+0xae/0x1a0 kernel/exit.c:893
 get_signal+0x2a7/0x1290 kernel/signal.c:2739
 do_signal+0x2b/0x840 arch/x86/kernel/signal.c:784
 exit_to_usermode_loop+0x24a/0x2c0 arch/x86/entry/common.c:161
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x38b/0x3b0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13988 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/24 18:59 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 ce7ca010 .config console log report ci2-upstream-kcsan-gce
2020/05/19 15:39 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6d882fd2 .config console log report ci2-upstream-kcsan-gce
2020/05/18 04:47 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 37bccd4e .config console log report ci2-upstream-kcsan-gce
2020/04/09 01:54 https://github.com/google/ktsan.git kcsan 40959e34d670 a8c6a3f8 .config console log report ci2-upstream-kcsan-gce
2020/02/10 18:29 https://github.com/google/ktsan.git kcsan f60f0f543333 18847f55 .config console log report ci2-upstream-kcsan-gce
2020/02/07 01:32 https://github.com/google/ktsan.git kcsan 245a43005292 06150bf1 .config console log report ci2-upstream-kcsan-gce
2020/02/01 13:38 https://github.com/google/ktsan.git kcsan 245a43005292 326d4c78 .config console log report ci2-upstream-kcsan-gce
2020/01/30 20:53 https://github.com/google/ktsan.git kcsan 245a43005292 5ed23f9a .config console log report ci2-upstream-kcsan-gce
2020/01/24 00:20 https://github.com/google/ktsan.git kcsan 245a43005292 11ebf937 .config console log report ci2-upstream-kcsan-gce
2020/01/22 07:59 https://github.com/google/ktsan.git kcsan 245a43005292 8eda0b95 .config console log report ci2-upstream-kcsan-gce
2020/01/17 15:22 https://github.com/google/ktsan.git kcsan 245a43005292 3de7aabb .config console log report ci2-upstream-kcsan-gce
2020/01/11 23:04 https://github.com/google/ktsan.git kcsan 245a43005292 4c04afaa .config console log report ci2-upstream-kcsan-gce
2020/01/08 14:35 https://github.com/google/ktsan.git kcsan 245a43005292 ddc3e859 .config console log report ci2-upstream-kcsan-gce
2020/01/06 22:36 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config console log report ci2-upstream-kcsan-gce
2020/01/06 22:29 https://github.com/google/ktsan.git kcsan 245a43005292 53430d97 .config console log report ci2-upstream-kcsan-gce
2019/12/28 11:39 https://github.com/google/ktsan.git kcsan 245a43005292 af6b8ef8 .config console log report ci2-upstream-kcsan-gce
2019/12/26 05:45 https://github.com/google/ktsan.git kcsan 245a43005292 be5c2c81 .config console log report ci2-upstream-kcsan-gce
2019/12/20 13:23 https://github.com/google/ktsan.git kcsan 245a43005292 34011c05 .config console log report ci2-upstream-kcsan-gce
2019/12/19 14:30 https://github.com/google/ktsan.git kcsan 245a43005292 36650b4b .config console log report ci2-upstream-kcsan-gce
2019/12/18 04:31 https://github.com/google/ktsan.git kcsan 245a43005292 64ca0a37 .config console log report ci2-upstream-kcsan-gce
2019/12/11 00:52 https://github.com/google/ktsan.git kcsan ef798c30ba4e 101194eb .config console log report ci2-upstream-kcsan-gce
2019/12/05 11:59 https://github.com/google/ktsan.git kcsan ef798c30ba4e 9fd5a512 .config console log report ci2-upstream-kcsan-gce
2019/12/05 06:50 https://github.com/google/ktsan.git kcsan ef798c30ba4e b2088328 .config console log report ci2-upstream-kcsan-gce
2019/11/20 08:53 https://github.com/google/ktsan.git kcsan 5863cc791e4c 432c7650 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.