============================================
WARNING: possible recursive locking detected
syzkaller #0 Tainted: G L
--------------------------------------------
syz-executor/18215 is trying to acquire lock:
ffff88804a299070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
ffff88804a299070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
but task is already holding lock:
ffff888026fe1070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
ffff888026fe1070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x3cd/0xcf0 net/hsr/hsr_device.c:330
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 syz-executor/18215: 10, last CPU#0:
#0: ffffffff8f4f2ab8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline]
#0: ffffffff8f4f2ab8 (tomoyo_ss){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:305 [inline]
#0: ffffffff8f4f2ab8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1112 [inline]
#0: ffffffff8f4f2ab8 (tomoyo_ss){.+.+}-{0:0}, at: tomoyo_check_open_permission+0x1d3/0x470 security/tomoyo/file.c:772
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8ed5c8a0 (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: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: hsr_announce+0x89/0x370 net/hsr/hsr_device.c:446
#4: ffff888026fe1070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:353 [inline]
#4: ffff888026fe1070 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x3cd/0xcf0 net/hsr/hsr_device.c:330
#5: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#5: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#5: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0xb9/0x2b70 net/hsr/hsr_forward.c:772
#6: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#6: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:902 [inline]
#6: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x29b/0x3920 net/core/dev.c:4872
#7: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#7: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#7: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x189/0x19d0 net/bridge/br_device.c:52
#8: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#8: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:902 [inline]
#8: ffffffff8ed5c900 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x29b/0x3920 net/core/dev.c:4872
#9: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#9: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#9: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: hsr_dev_xmit+0x2d/0x360 net/hsr/hsr_device.c:229
stack backtrace:
CPU: 0 UID: 0 PID: 18215 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
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+0x27a/0x290 kernel/locking/lockdep.c:3085
check_deadlock kernel/locking/lockdep.c:3137 [inline]
validate_chain kernel/locking/lockdep.c:3939 [inline]
__lock_acquire+0x25db/0x2de0 kernel/locking/lockdep.c:5288
lock_acquire+0x115/0x350 kernel/locking/lockdep.c:5942
__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:5432 [inline]
netdev_start_xmit include/linux/netdevice.h:5441 [inline]
xmit_one net/core/dev.c:3953 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3969
__dev_queue_xmit+0x14d1/0x3920 net/core/dev.c:4958
dev_queue_xmit include/linux/netdevice.h:3464 [inline]
br_dev_queue_push_xmit+0x370/0x4b0 net/bridge/br_forward.c:53
NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:325
br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:325
__br_forward+0x397/0x540 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver net/bridge/br_forward.c:191 [inline]
br_flood+0x3e3/0x8d0 net/bridge/br_forward.c:245
br_dev_xmit+0x11eb/0x19d0 net/bridge/br_device.c:108
__netdev_start_xmit include/linux/netdevice.h:5432 [inline]
netdev_start_xmit include/linux/netdevice.h:5441 [inline]
xmit_one net/core/dev.c:3953 [inline]
dev_hard_start_xmit+0x2cd/0x830 net/core/dev.c:3969
__dev_queue_xmit+0x14d1/0x3920 net/core/dev.c:4958
dev_queue_xmit include/linux/netdevice.h:3464 [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_hsr_supervision_frame+0x733/0xcf0 net/hsr/hsr_device.c:364
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:758
irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
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:unwind_next_frame+0x99b/0x2550 arch/x86/kernel/unwind_orc.c:-1
Code: 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 fa 05 c0 00 48 8b 3b 48 85 ff 0f 84 db 0d 00 00 48 83 c7 50 e9 2d 01 00 00 <48> 8b 44 24 38 42 80 3c 20 00 74 0c 48 89 ef e8 d1 05 c0 00 49 8d
RSP: 0000:ffffc9000653f260 EFLAGS: 00000246
RAX: ffffc9000653f33d RBX: 0000000000000003 RCX: ffffffff909d253c
RDX: ffffffff9120ae98 RSI: ffffffff9120ae5e RDI: ffffffff8c6dad20
RBP: ffffc9000653f340 R08: 0000000000000013 R09: 0000000000000000
R10: ffffc9000653f358 R11: ffffffff81b2c450 R12: dffffc0000000000
R13: ffffffff9120ae94 R14: ffffc9000653f308 R15: 1ffff92000ca7e61
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
poison_kmalloc_redzone mm/kasan/common.c:409 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5414 [inline]
__kmalloc_noprof+0x36b/0x720 mm/slub.c:5439
_kmalloc_noprof include/linux/slab.h:995 [inline]
tomoyo_realpath_from_path+0xef/0x640 security/tomoyo/realpath.c:251
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_compat_sys_openat fs/open.c:1485 [inline]
__se_compat_sys_openat fs/open.c:1483 [inline]
__ia32_compat_sys_openat+0x131/0x160 fs/open.c:1483
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
do_int80_emulation+0x198/0x500 arch/x86/entry/syscall_32.c:166
asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:598
RIP: 0023:0xf71675ab
Code: 57 56 53 8b 44 24 14 f6 00 08 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 cd 80 <5b> 5e 5f 5d c3 5b 5e 5f 5d e9 f7 a1 ff ff 66 90 66 90 66 90 90 53
RSP: 002b:00000000f754cafc EFLAGS: 00000246 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000f754cc40
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
----------------
Code disassembly (best guess):
0: 89 d8 mov %ebx,%eax
2: 48 c1 e8 03 shr $0x3,%rax
6: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
b: 74 08 je 0x15
d: 48 89 df mov %rbx,%rdi
10: e8 fa 05 c0 00 call 0xc0060f
15: 48 8b 3b mov (%rbx),%rdi
18: 48 85 ff test %rdi,%rdi
1b: 0f 84 db 0d 00 00 je 0xdfc
21: 48 83 c7 50 add $0x50,%rdi
25: e9 2d 01 00 00 jmp 0x157
* 2a: 48 8b 44 24 38 mov 0x38(%rsp),%rax <-- trapping instruction
2f: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1)
34: 74 0c je 0x42
36: 48 89 ef mov %rbp,%rdi
39: e8 d1 05 c0 00 call 0xc0060f
3e: 49 rex.WB
3f: 8d .byte 0x8d