syzbot


KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb (5)

Status: moderation: reported on 2024/09/20 02:07
Subsystems: virt
[Documentation on labels]
Reported-by: syzbot+17f8dd7cdf8903cbd75f@syzkaller.appspotmail.com
First crash: 22h43m, last: 6h32m
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb virt 47 330d 511d 0/28 auto-obsoleted due to no activity on 2023/11/30 12:57
upstream KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb (4) virt 3 57d 93d 0/28 auto-obsoleted due to no activity on 2024/08/29 17:45
upstream KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb (2) virt 3 237d 264d 0/28 auto-obsoleted due to no activity on 2024/03/02 22:45
upstream KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb (3) virt 37 122d 178d 0/28 auto-obsoleted due to no activity on 2024/06/18 13:46

Sample crash report:
==================================================================
BUG: KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb

read to 0xffff888101f5e978 of 2 bytes by task 3252 on cpu 0:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:885 [inline]
 virtqueue_disable_cb+0x63/0x180 drivers/virtio/virtio_ring.c:2446
 start_xmit+0x14b/0x1260 drivers/net/virtio_net.c:3061
 __netdev_start_xmit include/linux/netdevice.h:4916 [inline]
 netdev_start_xmit include/linux/netdevice.h:4925 [inline]
 xmit_one net/core/dev.c:3588 [inline]
 dev_hard_start_xmit+0x119/0x3f0 net/core/dev.c:3604
 sch_direct_xmit+0x1a9/0x580 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:3817 [inline]
 __dev_queue_xmit+0xf46/0x1fe0 net/core/dev.c:4390
 dev_queue_xmit include/linux/netdevice.h:3094 [inline]
 neigh_hh_output include/net/neighbour.h:526 [inline]
 neigh_output include/net/neighbour.h:540 [inline]
 ip_finish_output2+0x73d/0x8b0 net/ipv4/ip_output.c:236
 ip_finish_output+0x11a/0x2a0 net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip_output+0xab/0x170 net/ipv4/ip_output.c:434
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:130 [inline]
 __ip_queue_xmit+0xbcc/0xbf0 net/ipv4/ip_output.c:536
 ip_queue_xmit+0x38/0x50 net/ipv4/ip_output.c:550
 __tcp_transmit_skb+0x15b0/0x1970 net/ipv4/tcp_output.c:1466
 tcp_transmit_skb net/ipv4/tcp_output.c:1484 [inline]
 tcp_write_xmit+0x1410/0x3220 net/ipv4/tcp_output.c:2830
 __tcp_push_pending_frames+0x6a/0x1a0 net/ipv4/tcp_output.c:3015
 tcp_push+0x320/0x340 net/ipv4/tcp.c:750
 tcp_sendmsg_locked+0x21ff/0x2700 net/ipv4/tcp.c:1325
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1357
 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+0x15e/0x1a0 net/socket.c:1166
 new_sync_write fs/read_write.c:590 [inline]
 vfs_write+0x76a/0x910 fs/read_write.c:683
 ksys_write+0xeb/0x1b0 fs/read_write.c:736
 __do_sys_write fs/read_write.c:748 [inline]
 __se_sys_write fs/read_write.c:745 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:745
 x64_sys_call+0x27dd/0x2d60 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

write to 0xffff888101f5e978 of 2 bytes by interrupt on cpu 1:
 virtqueue_disable_cb_split drivers/virtio/virtio_ring.c:886 [inline]
 virtqueue_disable_cb+0x85/0x180 drivers/virtio/virtio_ring.c:2446
 skb_xmit_done+0x5f/0x140 drivers/net/virtio_net.c:715
 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
 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705
 wq_worker_running+0x49/0x130 kernel/workqueue.c:1399
 schedule_timeout+0xca/0x2c0 kernel/time/timer.c:2615
 schedule_timeout_uninterruptible kernel/time/timer.c:2649 [inline]
 msleep+0x4b/0x70 kernel/time/timer.c:2770
 hub_port_debounce+0x18b/0x210 drivers/usb/core/hub.c:4679
 hub_port_debounce_be_stable drivers/usb/core/hub.h:183 [inline]
 hub_port_connect drivers/usb/core/hub.c:5373 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
 port_event drivers/usb/core/hub.c:5821 [inline]
 hub_event+0x14ce/0x2910 drivers/usb/core/hub.c:5903
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
 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

value changed: 0x0000 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 11989 Comm: kworker/1:10 Tainted: G        W          6.11.0-syzkaller-07341-gbaeb9a7d8b60 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: usb_hub_wq hub_event
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/20 18:17 upstream baeb9a7d8b60 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb
2024/09/20 02:06 upstream 2004cef11ea0 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in virtqueue_disable_cb / virtqueue_disable_cb
* Struck through repros no longer work on HEAD.