syzbot


KCSAN: data-race in hrtimer_reprogram / print_cpu (9)

Status: auto-obsoleted due to no activity on 2024/04/14 23:48
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+28abd6e8a9f5c33cb000@syzkaller.appspotmail.com
First crash: 102d, last: 47d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (6) kernel 19 279d 465d 0/26 auto-obsoleted due to no activity on 2023/08/26 13:01
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu kernel 1 1498d 1498d 0/26 auto-closed as invalid on 2020/05/29 16:43
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (2) kernel 1 1332d 1332d 0/26 auto-closed as invalid on 2020/10/08 05:09
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (5) kernel 11 558d 642d 0/26 auto-obsoleted due to no activity on 2022/11/20 13:25
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (3) kernel 1 901d 901d 0/26 auto-closed as invalid on 2021/12/12 15:07
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (10) kernel 1 23h33m 23h32m 0/26 moderation: reported on 2024/04/26 11:32
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (7) kernel 3 233d 244d 0/26 auto-obsoleted due to no activity on 2023/10/11 12:54
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (4) kernel 1 865d 865d 0/26 auto-closed as invalid on 2022/01/17 18:45
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (8) kernel 1 157d 137d 0/26 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 0xffff888237c1f0e0 of 8 bytes by task 5902 on cpu 0:
 __hrtimer_reprogram kernel/time/hrtimer.c:661 [inline]
 hrtimer_reprogram+0x1a8/0x220 kernel/time/hrtimer.c:868
 hrtimer_start_range_ns+0x508/0x570 kernel/time/hrtimer.c:1303
 hrtimer_start_expires include/linux/hrtimer.h:394 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1969 [inline]
 do_nanosleep+0x85/0x2f0 kernel/time/hrtimer.c:2045
 hrtimer_nanosleep+0xe7/0x1e0 kernel/time/hrtimer.c:2101
 common_nsleep+0x68/0x80 kernel/time/posix-timers.c:1350
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline]
 __se_sys_clock_nanosleep+0x202/0x230 kernel/time/posix-timers.c:1373
 __x64_sys_clock_nanosleep+0x55/0x60 kernel/time/posix-timers.c:1373
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888237c1f0e0 of 8 bytes by task 5960 on cpu 1:
 print_cpu+0x2fb/0x640 kernel/time/timer_list.c:133
 timer_list_show+0x115/0x180 kernel/time/timer_list.c:291
 seq_read_iter+0x612/0x8f0 fs/seq_file.c:272
 proc_reg_read_iter+0x114/0x180 fs/proc/inode.c:299
 call_read_iter include/linux/fs.h:2081 [inline]
 copy_splice_read+0x39f/0x5d0 fs/splice.c:365
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x268/0x660 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3b9/0x960 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000004e512ef872 -> 0x0000004e512cbe0b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5960 Comm: syz-executor.4 Not tainted 6.8.0-rc7-syzkaller-00260-gfa4b851b4ad6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
==================================================================

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/03/10 23:47 upstream fa4b851b4ad6 6ee49f2e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/03/01 08:58 upstream 87adedeba51a 352ab904 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/02/12 10:01 upstream 841c35169323 77b23aa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/01/24 21:31 upstream 443b349019f2 1e153dc8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/01/22 05:45 upstream 4fbbed787267 9bd8dcda .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/01/17 16:38 upstream 052d534373b7 c9a1c95b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in hrtimer_reprogram / print_cpu
2024/01/15 21:32 upstream 052d534373b7 2a7bcc7f .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.