[moderation] [virt?] KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 92e5605a199e Merge tag 'linux_kselftest-fixes-6.10-rc5' of..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=110f1bfe980000
kernel config: https://syzkaller.appspot.com/x/.config?x=704451bc2941bcb0
dashboard link: https://syzkaller.appspot.com/bug?extid=192d1245cb1d0cb43484
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [eper...@redhat.com jaso...@redhat.com linux-...@vger.kernel.org m...@redhat.com virtual...@lists.linux.dev xuan...@linux.alibaba.com]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f9372939a8c4/disk-92e5605a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a0db084d0cae/vmlinux-92e5605a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f39e8696548d/bzImage-92e5605a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+192d12...@syzkaller.appspotmail.com

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

read to 0xffff888102a2f478 of 2 bytes by interrupt on cpu 1:
virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:885 [inline]
virtqueue_disable_cb+0x63/0x180 drivers/virtio/virtio_ring.c:2446
skb_xmit_done+0x5f/0x140 drivers/net/virtio_net.c:673
vring_interrupt+0x157/0x180 drivers/virtio/virtio_ring.c:2595
__handle_irq_event_percpu+0x95/0x490 kernel/irq/handle.c:158
handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
handle_irq_event+0x64/0xf0 kernel/irq/handle.c:210
handle_edge_irq+0x16d/0x5b0 kernel/irq/chip.c:831
generic_handle_irq_desc include/linux/irqdesc.h:173 [inline]
handle_irq arch/x86/kernel/irq.c:247 [inline]
call_irq_handler arch/x86/kernel/irq.c:259 [inline]
__common_interrupt+0x58/0xe0 arch/x86/kernel/irq.c:285
common_interrupt+0x7c/0x90 arch/x86/kernel/irq.c:278
asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
__preempt_count_dec_and_test arch/x86/include/asm/preempt.h:94 [inline]
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x3d/0x60 kernel/locking/spinlock.c:194
__mod_timer+0x604/0x7f0 kernel/time/timer.c:1186
schedule_timeout+0xc5/0x2c0 kernel/time/timer.c:2580
rcu_gp_fqs_loop+0x29f/0xbd0 kernel/rcu/tree.c:2000
rcu_gp_kthread+0x28/0x250 kernel/rcu/tree.c:2202
kthread+0x1d1/0x210 kernel/kthread.c:389
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

write to 0xffff888102a2f478 of 2 bytes by task 3252 on cpu 0:
virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:886 [inline]
virtqueue_disable_cb+0x85/0x180 drivers/virtio/virtio_ring.c:2446
start_xmit+0x125/0xb70 drivers/net/virtio_net.c:2568
__netdev_start_xmit include/linux/netdevice.h:4882 [inline]
netdev_start_xmit include/linux/netdevice.h:4896 [inline]
xmit_one net/core/dev.c:3578 [inline]
dev_hard_start_xmit+0x119/0x3f0 net/core/dev.c:3594
sch_direct_xmit+0x1b0/0x580 net/sched/sch_generic.c:343
__dev_xmit_skb net/core/dev.c:3807 [inline]
__dev_queue_xmit+0xee7/0x1e50 net/core/dev.c:4359
dev_queue_xmit include/linux/netdevice.h:3095 [inline]
neigh_hh_output include/net/neighbour.h:526 [inline]
neigh_output include/net/neighbour.h:540 [inline]
ip_finish_output2+0x73b/0x8b0 net/ipv4/ip_output.c:235
ip_finish_output+0x11a/0x2a0 net/ipv4/ip_output.c:323
NF_HOOK_COND include/linux/netfilter.h:303 [inline]
ip_output+0xab/0x170 net/ipv4/ip_output.c:433
dst_output include/net/dst.h:450 [inline]
ip_local_out net/ipv4/ip_output.c:129 [inline]
__ip_queue_xmit+0xbca/0xbf0 net/ipv4/ip_output.c:535
ip_queue_xmit+0x38/0x50 net/ipv4/ip_output.c:549
__tcp_transmit_skb+0x15b0/0x1970 net/ipv4/tcp_output.c:1466
tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline]
tcp_write_xmit+0x1273/0x31c0 net/ipv4/tcp_output.c:2829
__tcp_push_pending_frames+0x6a/0x1a0 net/ipv4/tcp_output.c:3014
tcp_push+0x320/0x340 net/ipv4/tcp.c:744
tcp_sendmsg_locked+0x2127/0x2640 net/ipv4/tcp.c:1319
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1351
inet_sendmsg+0x77/0xd0 net/ipv4/af_inet.c:853
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x102/0x180 net/socket.c:745
sock_write_iter+0x164/0x1b0 net/socket.c:1160
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0x78f/0x900 fs/read_write.c:590
ksys_write+0xeb/0x1b0 fs/read_write.c:643
__do_sys_write fs/read_write.c:655 [inline]
__se_sys_write fs/read_write.c:652 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:652
x64_sys_call+0x27ef/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:2
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: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3252 Comm: syz-fuzzer Not tainted 6.10.0-rc4-syzkaller-00045-g92e5605a199e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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