[moderation] [kernel?] KCSAN: data-race in clockevents_program_event / print_tickdevice (11)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 08733088b566 Merge tag 'rust-fixes-6.15-merge' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16b09998580000
kernel config: https://syzkaller.appspot.com/x/.config?x=bdb65086dcaf0454
dashboard link: https://syzkaller.appspot.com/bug?extid=ba24ce4936841ba0eea6
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/5d1a68089fbc/disk-08733088.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/341882c01f34/vmlinux-08733088.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b16db8197b4e/bzImage-08733088.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ba24ce...@syzkaller.appspotmail.com

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

write to 0xffff888237d17318 of 8 bytes by interrupt on cpu 1:
clockevents_program_event+0x36/0x1f0 kernel/time/clockevents.c:313
tick_program_event+0x7c/0xd0 kernel/time/tick-oneshot.c:44
hrtimer_interrupt+0x27c/0x4a0 kernel/time/hrtimer.c:1930
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
__sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
__tsan_read8+0x12/0x180 kernel/kcsan/core.c:1025
__netif_receive_skb_core+0x2063/0x2580 net/core/dev.c:5850
__netif_receive_skb_list_core+0x117/0x520 net/core/dev.c:5966
__netif_receive_skb_list net/core/dev.c:6033 [inline]
netif_receive_skb_list_internal+0x4e6/0x670 net/core/dev.c:6124
netif_receive_skb_list+0x31/0x230 net/core/dev.c:6176
xdp_recv_frames net/bpf/test_run.c:280 [inline]
xdp_test_run_batch net/bpf/test_run.c:361 [inline]
bpf_test_run_xdp_live+0xe17/0x1050 net/bpf/test_run.c:390
bpf_prog_test_run_xdp+0x526/0x8e0 net/bpf/test_run.c:1316
bpf_prog_test_run+0x20e/0x3a0 kernel/bpf/syscall.c:4427
__sys_bpf+0x440/0x800 kernel/bpf/syscall.c:5852
__do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
__x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5939
x64_sys_call+0x23da/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:322
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d17318 of 8 bytes by task 3483 on cpu 0:
print_tickdevice+0x144/0x340 kernel/time/timer_list.c:208
timer_list_show+0x79/0x180 kernel/time/timer_list.c:300
traverse+0x155/0x3c0 fs/seq_file.c:111
seq_read_iter+0x89f/0x970 fs/seq_file.c:195
proc_reg_read_iter+0x118/0x190 fs/proc/inode.c:299
new_sync_read fs/read_write.c:489 [inline]
vfs_read+0x5e6/0x710 fs/read_write.c:570
ksys_pread64 fs/read_write.c:761 [inline]
__do_sys_pread64 fs/read_write.c:769 [inline]
__se_sys_pread64 fs/read_write.c:766 [inline]
__x64_sys_pread64+0xfb/0x150 fs/read_write.c:766
x64_sys_call+0x26ad/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:18
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x7fffffffffffffff -> 0x000000096795b7e4

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3483 Comm: syz.4.12 Not tainted 6.14.0-syzkaller-11270-g08733088b566 #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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[syzbot]

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