KCSAN: data-race in do_cpu_nanosleep.isra.0 / do_signal

KCSAN: data-race in do_cpu_nanosleep.isra.0 / do_signal_stop

Status: closed as invalid on 2019/11/19 15:04
Subsystems: kernel
[Documentation on labels]
First crash: 1624d, last: 1624d

▶ ▼ Similar bugs (1)

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in do_cpu_nanosleep.isra.0 / do_signal_stop (2) kernel				1	1577d	1577d	0/26	auto-closed as invalid on 2020/03/07 20:04

Sample crash report:

==================================================================
BUG: KCSAN: data-race in do_cpu_nanosleep.isra.0 / do_signal_stop

read to 0xffff888100bef0d0 of 8 bytes by task 2184 on cpu 0:
 do_signal_stop+0x3e3/0x500 kernel/signal.c:2348
 get_signal+0x61b/0x1320 kernel/signal.c:2694
 do_signal+0x3b/0xbf0 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:159
 prepare_exit_to_usermode+0x180/0x1a0 arch/x86/entry/common.c:194
 swapgs_restore_regs_and_return_to_usermode+0x0/0x40

write to 0xffff888100bef0d0 of 8 bytes by task 2188 on cpu 1:
 do_cpu_nanosleep.isra.0+0x195/0x380 kernel/time/posix-cpu-timers.c:1265
 posix_cpu_nsleep+0xa8/0x140 kernel/time/posix-cpu-timers.c:1331
 process_cpu_nsleep+0x2c/0x40 kernel/time/posix-cpu-timers.c:1375
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1230 [inline]
 __se_sys_clock_nanosleep kernel/time/posix-timers.c:1208 [inline]
 __x64_sys_clock_nanosleep+0x1e4/0x280 kernel/time/posix-timers.c:1208
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2188 Comm: syz-executor.5 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2019/11/11 23:59	https://github.com/google/ktsan.git kcsan	94c006602e13	377d77fa	.config	console log	report					ci2-upstream-kcsan-gce

* ~~Struck through~~ repros no longer work on HEAD.