[moderation] [can?] KCSAN: data-race in can_receive / can_receive (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b7c90e3e717a Merge tag 'x86-urgent-2025-03-08' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15d87a54580000
kernel config: https://syzkaller.appspot.com/x/.config?x=523b0e2f15224775
dashboard link: https://syzkaller.appspot.com/bug?extid=20ff421ba10430178eae
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [linu...@vger.kernel.org linux-...@vger.kernel.org m...@pengutronix.de sock...@hartkopp.net]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1e0d66ec6161/disk-b7c90e3e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bbc181aa916b/vmlinux-b7c90e3e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/30761d6399d0/bzImage-b7c90e3e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+20ff42...@syzkaller.appspotmail.com

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

read-write to 0xffff888134e2b008 of 8 bytes by interrupt on cpu 1:
can_receive+0x4e/0x1f0 net/can/af_can.c:650
canfd_rcv+0xe7/0x180 net/can/af_can.c:703
__netif_receive_skb_one_core net/core/dev.c:5893 [inline]
__netif_receive_skb+0x123/0x280 net/core/dev.c:6006
process_backlog+0x22e/0x440 net/core/dev.c:6354
__napi_poll+0x63/0x3c0 net/core/dev.c:7188
napi_poll net/core/dev.c:7257 [inline]
net_rx_action+0x3a1/0x7f0 net/core/dev.c:7379
handle_softirqs+0xbf/0x280 kernel/softirq.c:561
do_softirq+0x5e/0x90 kernel/softirq.c:462
__local_bh_enable_ip+0x6e/0x70 kernel/softirq.c:389
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
tipc_nametbl_lookup_group+0x2b0/0x620 net/tipc/name_table.c:664
tipc_send_group_anycast net/tipc/socket.c:1027 [inline]
__tipc_sendmsg+0xc18/0x1c40 net/tipc/socket.c:1434
tipc_sendmsg+0x3e/0x60 net/tipc/socket.c:1399
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x140/0x180 net/socket.c:733
____sys_sendmsg+0x326/0x4b0 net/socket.c:2573
___sys_sendmsg net/socket.c:2627 [inline]
__sys_sendmsg+0x19d/0x230 net/socket.c:2659
__do_sys_sendmsg net/socket.c:2664 [inline]
__se_sys_sendmsg net/socket.c:2662 [inline]
__x64_sys_sendmsg+0x46/0x50 net/socket.c:2662
x64_sys_call+0x2734/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:47
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

read-write to 0xffff888134e2b008 of 8 bytes by interrupt on cpu 0:
can_receive+0x4e/0x1f0 net/can/af_can.c:650
canfd_rcv+0xe7/0x180 net/can/af_can.c:703
__netif_receive_skb_one_core net/core/dev.c:5893 [inline]
__netif_receive_skb+0x123/0x280 net/core/dev.c:6006
process_backlog+0x22e/0x440 net/core/dev.c:6354
__napi_poll+0x63/0x3c0 net/core/dev.c:7188
napi_poll net/core/dev.c:7257 [inline]
net_rx_action+0x3a1/0x7f0 net/core/dev.c:7379
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: 0x0000000000000985 -> 0x0000000000000986

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Tainted: G W 6.14.0-rc5-syzkaller-00234-gb7c90e3e717a #0
Tainted: [W]=WARN
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.