syzbot


KCSAN: data-race in hrtimer_reprogram / print_cpu (12)

Status: auto-obsoleted due to no activity on 2025/03/19 14:48
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+47ebcf8d96df0c45cad5@syzkaller.appspotmail.com
First crash: 191d, last: 112d
Similar bugs (12)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (11) kernel 6 318d 337d 0/28 auto-obsoleted due to no activity on 2024/08/04 04:55
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (9) kernel 7 430d 485d 0/28 auto-obsoleted due to no activity on 2024/04/14 23:48
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (13) kernel 1 48d 48d 0/28 moderation: reported on 2025/03/28 00:02
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (6) kernel 19 662d 847d 0/28 auto-obsoleted due to no activity on 2023/08/26 13:01
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu kernel 1 1881d 1881d 0/28 auto-closed as invalid on 2020/05/29 16:43
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (2) kernel 1 1714d 1714d 0/28 auto-closed as invalid on 2020/10/08 05:09
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (5) kernel 11 941d 1024d 0/28 auto-obsoleted due to no activity on 2022/11/20 13:25
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (3) kernel 1 1284d 1284d 0/28 auto-closed as invalid on 2021/12/12 15:07
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (10) kernel 2 382d 383d 0/28 auto-obsoleted due to no activity on 2024/06/01 18:17
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (7) kernel 3 616d 626d 0/28 auto-obsoleted due to no activity on 2023/10/11 12:54
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (4) kernel 1 1248d 1248d 0/28 auto-closed as invalid on 2022/01/17 18:45
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (8) kernel 1 540d 520d 0/28 auto-obsoleted due to no activity on 2023/12/26 20:48

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

write to 0xffff888237d1fd20 of 8 bytes by task 5641 on cpu 1:
 __hrtimer_reprogram kernel/time/hrtimer.c:648 [inline]
 hrtimer_reprogram+0x1a2/0x220 kernel/time/hrtimer.c:855
 hrtimer_start_range_ns+0x507/0x580 kernel/time/hrtimer.c:1293
 hrtimer_start_expires include/linux/hrtimer.h:274 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2000 [inline]
 do_nanosleep+0x86/0x300 kernel/time/hrtimer.c:2075
 hrtimer_nanosleep+0xc4/0x1c0 kernel/time/hrtimer.c:2125
 common_nsleep+0x68/0x90 kernel/time/posix-timers.c:1356
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1402 [inline]
 __se_sys_clock_nanosleep+0x20a/0x240 kernel/time/posix-timers.c:1379
 __x64_sys_clock_nanosleep+0x55/0x70 kernel/time/posix-timers.c:1379
 x64_sys_call+0x25b8/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:231
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d1fd20 of 8 bytes by task 5661 on cpu 0:
 print_cpu+0x2fb/0x670 kernel/time/timer_list.c:133
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:295
 seq_read_iter+0x655/0x930 fs/seq_file.c:272
 proc_reg_read_iter+0x118/0x190 fs/proc/inode.c:299
 copy_splice_read+0x3a0/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x269/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000011ed8ec200 -> 0x00000011ed64de6b

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5661 Comm: syz.3.697 Not tainted 6.13.0-syzkaller-02526-gc4b9570cfb63 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/22 14:47 upstream c4b9570cfb63 da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2025/01/21 22:47 upstream b9d8a295ed6b da72ac06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2025/01/20 16:00 upstream ffd294d346d1 6e87cfa2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/12/11 08:27 upstream f92f4749861b cfc402b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/11/04 15:44 upstream 59b723cd2adb f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
* Struck through repros no longer work on HEAD.