syzbot


KCSAN: data-race in hrtimer_reprogram / print_cpu (4)

Status: auto-closed as invalid on 2022/01/17 18:45
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 357d, last: 357d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu 1 990d 990d 0/24 auto-closed as invalid on 2020/05/29 16:43
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (2) 1 824d 824d 0/24 auto-closed as invalid on 2020/10/08 05:09
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (5) 11 51d 134d 0/24 auto-obsoleted due to no activity on 2022/11/20 13:25
upstream KCSAN: data-race in hrtimer_reprogram / print_cpu (3) 1 393d 393d 0/24 auto-closed as invalid on 2021/12/12 15:07

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

write to 0xffff888237c1d9a0 of 8 bytes by task 21424 on cpu 0:
 __hrtimer_reprogram kernel/time/hrtimer.c:659 [inline]
 hrtimer_reprogram+0x1e2/0x250 kernel/time/hrtimer.c:866
 hrtimer_start_range_ns+0xf8/0x140 kernel/time/hrtimer.c:1299
 hrtimer_start_expires include/linux/hrtimer.h:432 [inline]
 hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1965 [inline]
 do_nanosleep+0x97/0x3a0 kernel/time/hrtimer.c:2041
 hrtimer_nanosleep+0x10b/0x200 kernel/time/hrtimer.c:2097
 common_nsleep+0x69/0x80 kernel/time/posix-timers.c:1227
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline]
 __se_sys_clock_nanosleep+0x1f1/0x220 kernel/time/posix-timers.c:1245
 __x64_sys_clock_nanosleep+0x51/0x60 kernel/time/posix-timers.c:1245
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237c1d9a0 of 8 bytes by task 21426 on cpu 1:
 print_cpu+0x32e/0x690 kernel/time/timer_list.c:133
 timer_list_show+0x114/0x180 kernel/time/timer_list.c:291
 seq_read_iter+0x2e1/0x930 fs/seq_file.c:230
 proc_reg_read_iter+0xfc/0x170 fs/proc/inode.c:300
 call_read_iter include/linux/fs.h:2156 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000015225377fb6 -> 0x0000015224eab15b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 21426 Comm: syz-executor.5 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/12/13 18:39 upstream 2585cf9dfaad 0304899b .config log report info KCSAN: data-race in hrtimer_reprogram / print_cpu
* Struck through repros no longer work on HEAD.