[moderation] [kernel?] KCSAN: data-race in clockevents_program_min_delta / print_tickdevice (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: defaf1a2113a Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143bd483980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d16924117a4f7e9
dashboard link: https://syzkaller.appspot.com/bug?extid=216b245d7c9f92402d7f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [anna-...@linutronix.de fred...@kernel.org linux-...@vger.kernel.org tg...@linutronix.de]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f1dfb9104e6c/disk-defaf1a2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/836a50ed484b/vmlinux-defaf1a2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/060b15e1bfc7/bzImage-defaf1a2.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+216b24...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in clockevents_program_min_delta / print_tickdevice

read-write to 0xffff888237c1c240 of 8 bytes by task 10879 on cpu 0:
clockevents_program_min_delta+0xb6/0x260 kernel/time/clockevents.c:246
clockevents_program_event+0x180/0x1f0
tick_program_event+0x7c/0xd0 kernel/time/tick-oneshot.c:44
__hrtimer_reprogram kernel/time/hrtimer.c:679 [inline]
hrtimer_reprogram+0x1cf/0x220 kernel/time/hrtimer.c:864
hrtimer_start_range_ns+0x512/0x580 kernel/time/hrtimer.c:1303
hrtimer_start_expires include/linux/hrtimer.h:289 [inline]
hrtimer_restart include/linux/hrtimer.h:297 [inline]
common_hrtimer_rearm+0xa6/0xc0 kernel/time/posix-timers.c:249
posixtimer_rearm+0xc7/0x1a0 kernel/time/posix-timers.c:267
dequeue_signal+0x282/0x430 kernel/signal.c:696
get_signal+0x37d/0x1080 kernel/signal.c:2796
arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x59/0x130 kernel/entry/common.c:218
do_syscall_64+0xd6/0x1c0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c1c240 of 8 bytes by task 10899 on cpu 1:
print_tickdevice+0x2ae/0x340 kernel/time/timer_list.c:234
timer_list_show+0x79/0x180 kernel/time/timer_list.c:300
seq_read_iter+0x65b/0x940 fs/seq_file.c:272
proc_reg_read_iter+0x11e/0x190 fs/proc/inode.c:299
copy_splice_read+0x3a4/0x5d0 fs/splice.c:365
do_splice_read fs/splice.c:985 [inline]
splice_direct_to_actor+0x26c/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+0x3ab/0x950 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
x64_sys_call+0xed5/0x2d60 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: 0x0000000000335279 -> 0x000000000033527c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10899 Comm: syz.1.1736 Tainted: G W 6.11.0-rc1-syzkaller-00293-gdefaf1a2113a #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.