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KCSAN: data-race in do_timer_create / do_timer_create (2)

Status: auto-closed as invalid on 2021/07/28 07:48
Subsystems: kernel
[Documentation on labels]
First crash: 1377d, last: 1377d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in do_timer_create / do_timer_create kernel 1 1420d 1420d 0/28 auto-closed as invalid on 2021/06/14 21:07
upstream KCSAN: data-race in do_timer_create / do_timer_create (3) kernel 2 1247d 1252d 0/28 auto-closed as invalid on 2021/12/05 03:50
upstream KCSAN: data-race in do_timer_create / do_timer_create (8) kernel 9 679d 710d 23/28 fixed on 2023/09/28 17:51
upstream KCSAN: data-race in do_timer_create / do_timer_create (6) kernel 1 917d 917d 0/28 auto-obsoleted due to no activity on 2022/10/31 13:32
upstream KCSAN: data-race in do_timer_create / do_timer_create (7) kernel 1 874d 874d 0/28 auto-obsoleted due to no activity on 2022/12/12 21:42
upstream KCSAN: data-race in do_timer_create / do_timer_create (5) kernel 10 971d 1076d 0/28 auto-closed as invalid on 2022/09/07 15:06
upstream KCSAN: data-race in do_timer_create / do_timer_create (4) kernel 18 1115d 1202d 0/28 auto-closed as invalid on 2022/04/16 01:14

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

write to 0xffff8881559c023c of 4 bytes by task 21229 on cpu 1:
 posix_timer_add kernel/time/posix-timers.c:154 [inline]
 do_timer_create+0x349/0xad0 kernel/time/posix-timers.c:516
 __do_sys_timer_create kernel/time/posix-timers.c:586 [inline]
 __se_sys_timer_create kernel/time/posix-timers.c:577 [inline]
 __x64_sys_timer_create+0xa3/0xd0 kernel/time/posix-timers.c:577
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881559c023c of 4 bytes by task 21227 on cpu 0:
 posix_timer_add kernel/time/posix-timers.c:143 [inline]
 do_timer_create+0x1b5/0xad0 kernel/time/posix-timers.c:516
 __do_sys_timer_create kernel/time/posix-timers.c:586 [inline]
 __se_sys_timer_create kernel/time/posix-timers.c:577 [inline]
 __x64_sys_timer_create+0xa3/0xd0 kernel/time/posix-timers.c:577
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000005 -> 0x00000006

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 21227 Comm: syz-executor.5 Not tainted 5.13.0-rc7-syzkaller #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
2021/06/23 07:41 upstream 0c18f29aae7c aba2b2fb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in do_timer_create / do_timer_create
* Struck through repros no longer work on HEAD.