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KCSAN: data-race in __lock_timer / __se_sys_timer_delete (3)

Status: auto-obsoleted due to no activity on 2023/06/15 18:17
Subsystems: kernel
[Documentation on labels]
First crash: 360d, last: 360d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __lock_timer / __se_sys_timer_delete (2) kernel 1 494d 494d 0/26 auto-obsoleted due to no activity on 2023/02/08 10:48
upstream KCSAN: data-race in __lock_timer / __se_sys_timer_delete kernel 1 900d 900d 0/26 auto-closed as invalid on 2021/12/23 00:32

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

write to 0xffff88811e6d6e60 of 8 bytes by task 32459 on cpu 1:
 __do_sys_timer_delete kernel/time/posix-timers.c:1032 [inline]
 __se_sys_timer_delete+0x1c3/0x2d0 kernel/time/posix-timers.c:1008
 __x64_sys_timer_delete+0x1f/0x30 kernel/time/posix-timers.c:1008
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88811e6d6e60 of 8 bytes by task 32458 on cpu 0:
 __posix_timers_find kernel/time/posix-timers.c:126 [inline]
 posix_timer_by_id kernel/time/posix-timers.c:137 [inline]
 __lock_timer+0x92/0x160 kernel/time/posix-timers.c:626
 do_timer_settime+0x103/0x240 kernel/time/posix-timers.c:918
 __do_sys_timer_settime kernel/time/posix-timers.c:956 [inline]
 __se_sys_timer_settime kernel/time/posix-timers.c:942 [inline]
 __x64_sys_timer_settime+0xe8/0x150 kernel/time/posix-timers.c:942
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff888103670040 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 32458 Comm: syz-executor.2 Not tainted 6.4.0-rc1-syzkaller-00025-gd295b66a7b66 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/05/11 18:16 upstream d295b66a7b66 0fbd49f4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __lock_timer / __se_sys_timer_delete
* Struck through repros no longer work on HEAD.