syzbot


KCSAN: data-race in perf_event_exit_event / perf_event_exit_event

Status: auto-closed as invalid on 2021/11/09 11:06
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 423d, last: 423d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in perf_event_exit_event / perf_event_exit_event (2) 1 311d 311d 0/24 auto-closed as invalid on 2022/03/02 02:45
upstream KCSAN: data-race in perf_event_exit_event / perf_event_exit_event (3) 1 125d 125d 0/24 auto-closed as invalid on 2022/09/03 15:29

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

write to 0xffff8881329d4b14 of 4 bytes by task 2585 on cpu 1:
 perf_event_wakeup kernel/events/core.c:6435 [inline]
 perf_event_exit_event+0x627/0x790 kernel/events/core.c:12650
 perf_event_exit_task_context kernel/events/core.c:12716 [inline]
 perf_event_exit_task+0x49a/0x630 kernel/events/core.c:12749
 do_exit+0x474/0x14a0 kernel/exit.c:834
 do_group_exit+0x19b/0x1a0 kernel/exit.c:922
 __do_sys_exit_group+0xb/0x10 kernel/exit.c:933
 __se_sys_exit_group+0x5/0x10 kernel/exit.c:931
 __x64_sys_exit_group+0x16/0x20 kernel/exit.c:931
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881329d4b14 of 4 bytes by task 2593 on cpu 0:
 perf_event_wakeup kernel/events/core.c:6433 [inline]
 perf_event_exit_event+0x5da/0x790 kernel/events/core.c:12650
 perf_event_exit_task_context kernel/events/core.c:12716 [inline]
 perf_event_exit_task+0x49a/0x630 kernel/events/core.c:12749
 do_exit+0x474/0x14a0 kernel/exit.c:834
 do_group_exit+0xce/0x1a0 kernel/exit.c:922
 get_signal+0xf93/0x15d0 kernel/signal.c:2868
 arch_do_signal_or_restart+0x8c/0x280 arch/x86/kernel/signal.c:865
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x109/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2593 Comm: syz-executor.3 Not tainted 5.15.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/10/05 11:02 upstream f6274b06e326 ce697b49 .config log report info KCSAN: data-race in perf_event_exit_event / perf_event_exit_event
* Struck through repros no longer work on HEAD.