[syzbot] [can?] KCSAN: data-race in can_send / can_send (5)

[syzbot <syzbot+78ce4489b812515d5e4d@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    0f52fd4f67c6 Merge tag 'bcachefs-2025-03-06' of git://evil..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12d12a54580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=523b0e2f15224775
dashboard link: https://syzkaller.appspot.com/bug?extid=78ce4489b812515d5e4d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/eb0d7b540c67/disk-0f52fd4f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/51c261332ad9/vmlinux-0f52fd4f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/38914a4790c8/bzImage-0f52fd4f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+78ce4489b812515d5e4d@syzkaller.appspotmail.com

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

read-write to 0xffff888117566290 of 8 bytes by interrupt on cpu 0:
 can_send+0x5a2/0x6d0 net/can/af_can.c:290
 bcm_can_tx+0x314/0x420 net/can/bcm.c:314
 bcm_tx_timeout_handler+0xea/0x280
 __run_hrtimer kernel/time/hrtimer.c:1801 [inline]
 __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1865
 hrtimer_run_softirq+0xe4/0x2c0 kernel/time/hrtimer.c:1882
 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-write to 0xffff888117566290 of 8 bytes by interrupt on cpu 1:
 can_send+0x5a2/0x6d0 net/can/af_can.c:290
 bcm_can_tx+0x314/0x420 net/can/bcm.c:314
 bcm_tx_timeout_handler+0xea/0x280
 __run_hrtimer kernel/time/hrtimer.c:1801 [inline]
 __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1865
 hrtimer_run_softirq+0xe4/0x2c0 kernel/time/hrtimer.c:1882
 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: 0x0000000000002b9d -> 0x0000000000002b9e

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Tainted: G        W          6.14.0-rc5-syzkaller-00109-g0f52fd4f67c6 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================


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