============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
udevd/4978 is trying to acquire lock:
ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
but task is already holding lock:
ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_prp_supervision_frame+0x1fb/0x8b0 net/hsr/hsr_device.c:401
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&hsr->seqnr_lock);
lock(&hsr->seqnr_lock);
*** DEADLOCK ***
May be due to missing lock nesting notation
locks held by udevd/4978: 13, last CPU#0:
#0: ffffffff8f2e27b8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline]
#0: ffffffff8f2e27b8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline]
#0: ffffffff8f2e27b8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1112 [inline]
#0: ffffffff8f2e27b8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_check_open_permission+0x1d3/0x470 security/tomoyo/file.c:772
#1: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#1: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#1: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
#1: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
#2: ffffc90000007cc0 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x5f0 kernel/time/timer.c:1745
#3: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#3: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: hsr_announce+0x89/0x370 net/hsr/hsr_device.c:446
#4: ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
#4: ffff8880693a5070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_prp_supervision_frame+0x1fb/0x8b0 net/hsr/hsr_device.c:401
#5: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#5: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0xb9/0x2b70 net/hsr/hsr_forward.c:772
#6: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#6: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:893 [inline]
#6: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x29b/0x3820 net/core/dev.c:4844
#7: ffff88807ab9f228 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: spin_trylock include/linux/spinlock.h:359 [inline]
#7: ffff88807ab9f228 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: qdisc_run_begin include/net/sch_generic.h:206 [inline]
#7: ffff88807ab9f228 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_xmit_skb net/core/dev.c:4249 [inline]
#7: ffff88807ab9f228 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#5){+...}-{3:3}, at: __dev_queue_xmit+0x1143/0x3820 net/core/dev.c:4884
#8: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#8: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#8: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: ip6_output+0x11e/0x540 net/ipv6/ip6_output.c:236
#9: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#9: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#9: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: ndisc_send_skb+0x203/0x1650 net/ipv6/ndisc.c:483
#10: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#10: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#10: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: ip6_output+0x11e/0x540 net/ipv6/ip6_output.c:236
#11: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#11: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:893 [inline]
#11: ffffffff8eb5a240 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x29b/0x3820 net/core/dev.c:4844
#12: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#12: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#12: ffffffff8eb5a1e0 (rcu_read_lock){....}-{1:3}, at: hsr_dev_xmit+0x2d/0x360 net/hsr/hsr_device.c:229
stack backtrace:
CPU: 0 UID: 0 PID: 4978 Comm: udevd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3057
check_deadlock kernel/locking/lockdep.c:3109 [inline]
validate_chain kernel/locking/lockdep.c:3911 [inline]
__lock_acquire+0x24df/0x2cf0 kernel/locking/lockdep.c:5253
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5886
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:182 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:205
spin_lock_bh include/linux/spinlock.h:353 [inline]
hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
__netdev_start_xmit include/linux/netdevice.h:5429 [inline]
netdev_start_xmit include/linux/netdevice.h:5438 [inline]
xmit_one net/core/dev.c:3937 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3953
__dev_queue_xmit+0x14c0/0x3820 net/core/dev.c:4926
NF_HOOK_COND include/linux/netfilter.h:314 [inline]
ip6_output+0x337/0x540 net/ipv6/ip6_output.c:248
dst_output include/net/dst.h:471 [inline]
NF_HOOK include/linux/netfilter.h:325 [inline]
ndisc_send_skb+0xcb2/0x1650 net/ipv6/ndisc.c:513
ndisc_send_ns net/ipv6/ndisc.c:672 [inline]
ndisc_solicit+0x374/0x670 net/ipv6/ndisc.c:763
neigh_probe net/core/neighbour.c:1093 [inline]
__neigh_event_send+0xf0c/0x1510 net/core/neighbour.c:1273
neigh_event_send_probe include/net/neighbour.h:480 [inline]
neigh_event_send include/net/neighbour.h:486 [inline]
neigh_resolve_output+0x1a1/0x720 net/core/neighbour.c:1600
NF_HOOK_COND include/linux/netfilter.h:314 [inline]
ip6_output+0x337/0x540 net/ipv6/ip6_output.c:248
ip6tunnel_xmit+0x200/0x620 include/net/ip6_tunnel.h:174
ip6_tnl_xmit+0x2034/0x27e0 net/ipv6/ip6_tunnel.c:1285
__gre6_xmit+0xa5c/0xd80 net/ipv6/ip6_gre.c:787
ip6gre_xmit_other net/ipv6/ip6_gre.c:873 [inline]
ip6gre_tunnel_xmit+0x9be/0xf50 net/ipv6/ip6_gre.c:900
__netdev_start_xmit include/linux/netdevice.h:5429 [inline]
netdev_start_xmit include/linux/netdevice.h:5438 [inline]
xmit_one net/core/dev.c:3937 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3953
sch_direct_xmit+0x257/0x4c0 net/sched/sch_generic.c:372
__dev_xmit_skb net/core/dev.c:4262 [inline]
__dev_queue_xmit+0x177f/0x3820 net/core/dev.c:4884
dev_queue_xmit include/linux/netdevice.h:3461 [inline]
hsr_xmit net/hsr/hsr_forward.c:440 [inline]
hsr_forward_do net/hsr/hsr_forward.c:603 [inline]
hsr_forward_skb+0x1701/0x2b70 net/hsr/hsr_forward.c:777
send_prp_supervision_frame+0x49a/0x8b0 net/hsr/hsr_device.c:432
hsr_announce+0x1db/0x370 net/hsr/hsr_device.c:448
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 kernel/softirq.c:767
irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x11/0xb0 kernel/rcu/tree.c:752
Code: 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 48 ff 05 cf 25 c4 11 6a 37 2d 0a 89 c3 83 f8 08 73 66 49 bf 00 00 00 00 00 fc ff df
RSP: 0018:ffffc90002dcf260 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffffff82484218 RCX: ffff88807e9f3e80
RDX: 00000000fbd97421 RSI: ffffffff8e4ddb69 RDI: ffffffff8c4cd780
RBP: 1ffff920005b9e6c R08: ffffffff8177710f R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8eb5a1e0 R12: dffffc0000000000
R13: ffffffff8177710f R14: ffffc90002dcf328 R15: 1ffff920005b9e65
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0xbe/0x2550 arch/x86/kernel/unwind_orc.c:495
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2677 [inline]
slab_free mm/slub.c:6377 [inline]
kfree+0x1c5/0x640 mm/slub.c:6692
tomoyo_realpath_from_path+0x605/0x640 security/tomoyo/realpath.c:286
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_check_open_permission+0x229/0x470 security/tomoyo/file.c:776
security_file_open+0xa9/0x240 security/security.c:2739
do_dentry_open+0x4a0/0x1380 fs/open.c:973
vfs_open+0x3b/0x340 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0x1443/0x1d60 fs/namei.c:5000
do_file_open+0x23e/0x4a0 fs/namei.c:5029
do_sys_openat2+0x115/0x200 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1434
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f10ab915c3a
Code: 41 89 f2 48 89 54 24 e0 41 83 e2 40 75 2a 89 f0 f7 d0 a9 00 00 41 00 74 1f 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 77 2e c3 0f 1f 44 00 00 48 8d 44 24 08 c7 44 24
RSP: 002b:00007ffe1810b5b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000055a791b58a30 RCX: 00007f10ab915c3a
RDX: 0000000000090800 RSI: 000055a791b2bfd0 RDI: 00000000ffffff9c
RBP: 000055a791b2bfd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 000055a791b397b0
R13: 00000000000000ff R14: 000055a76e105be0 R15: 00007ffe1810b840
----------------
Code disassembly (best guess):
0: 2e 0f 1f 84 00 00 00 cs nopl 0x0(%rax,%rax,1)
7: 00 00
9: 90 nop
a: 90 nop
b: 90 nop
c: 90 nop
d: 90 nop
e: 90 nop
f: 90 nop
10: 90 nop
11: 90 nop
12: 90 nop
13: 90 nop
14: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 90 nop
19: f3 0f 1e fa endbr64
1d: 41 57 push %r15
1f: 41 56 push %r14
21: 53 push %rbx
22: 65 48 ff 05 cf 25 c4 incq %gs:0x11c425cf(%rip) # 0x11c425f9
29: 11
* 2a: e8 6a 37 2d 0a call 0xa2d3799 <-- trapping instruction
2f: 89 c3 mov %eax,%ebx
31: 83 f8 08 cmp $0x8,%eax
34: 73 66 jae 0x9c
36: 49 bf 00 00 00 00 00 movabs $0xdffffc0000000000,%r15
3d: fc ff df