[moderation] [can?] KCSAN: data-race in can_send / can_stat_update (8)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cabb4685d57e Merge tag 'v6.14-rc-smb3-client-fixes-part2' ..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12c3cb24580000
kernel config: https://syzkaller.appspot.com/x/.config?x=fdf6e93ff35d9650
dashboard link: https://syzkaller.appspot.com/bug?extid=057eb4175bedeb91fdda
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ker...@pengutronix.de linu...@vger.kernel.org linux-...@vger.kernel.org m...@pengutronix.de o.re...@pengutronix.de ro...@protonic.nl sock...@hartkopp.net]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4058ad69c9f4/disk-cabb4685.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8831f44933a4/vmlinux-cabb4685.xz
kernel image: https://storage.googleapis.com/syzbot-assets/af6d6dde89bd/bzImage-cabb4685.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+057eb4...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in can_send / can_stat_update

read-write to 0xffff888115dca990 of 8 bytes by interrupt on cpu 0:
can_send+0x5a2/0x6d0 net/can/af_can.c:290
j1939_send_one+0x1a9/0x1e0 net/can/j1939/main.c:353
j1939_tp_tx_dat net/can/j1939/transport.c:646 [inline]
j1939_session_tx_dat net/can/j1939/transport.c:838 [inline]
j1939_xtp_txnext_transmiter net/can/j1939/transport.c:900 [inline]
j1939_tp_txtimer+0xcab/0x1a70 net/can/j1939/transport.c:1160
__run_hrtimer kernel/time/hrtimer.c:1738 [inline]
__hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1802
hrtimer_run_softirq+0xe4/0x2c0 kernel/time/hrtimer.c:1819
handle_softirqs+0xbf/0x280 kernel/softirq.c:561
run_ksoftirqd+0x1c/0x30 kernel/softirq.c:950
smpboot_thread_fn+0x31c/0x4c0 kernel/smpboot.c:164
kthread+0x4ae/0x520 kernel/kthread.c:464
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888115dca990 of 8 bytes by interrupt on cpu 1:
can_stat_update+0x1f3/0x6b0 net/can/proc.c:134
call_timer_fn+0x3a/0x300 kernel/time/timer.c:1789
expire_timers kernel/time/timer.c:1840 [inline]
__run_timers kernel/time/timer.c:2414 [inline]
__run_timer_base+0x417/0x640 kernel/time/timer.c:2426
run_timer_base kernel/time/timer.c:2435 [inline]
run_timer_softirq+0x31/0x70 kernel/time/timer.c:2445
handle_softirqs+0xbf/0x280 kernel/softirq.c:561
run_ksoftirqd+0x1c/0x30 kernel/softirq.c:950
smpboot_thread_fn+0x31c/0x4c0 kernel/smpboot.c:164
kthread+0x4ae/0x520 kernel/kthread.c:464
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000000000165b9 -> 0x00000000000165ba

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.13.0-syzkaller-09998-gcabb4685d57e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
==================================================================


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[syzbot]

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