============================================
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz-executor/5837 is trying to acquire lock:
ffff88805ad62f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88805ad62f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
but task is already holding lock:
ffff888057b4af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff888057b4af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x380/0xcb0 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
9 locks held by syz-executor/5837:
#0: ffff88802f330308 (&xt[i].mutex){+.+.}-{4:4}, at: xt_find_table_lock+0x54/0x3e0 net/netfilter/x_tables.c:1243
#1: ffffc90000007be0 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbe/0x5f0 kernel/time/timer.c:1745
#2: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#2: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: hsr_announce+0x83/0x360 net/hsr/hsr_device.c:419
#3: ffff888057b4af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#3: ffff888057b4af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x380/0xcb0 net/hsr/hsr_device.c:330
#4: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#4: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#4: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0x9e/0x2860 net/hsr/hsr_forward.c:736
#5: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#5: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:918 [inline]
#5: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2ab/0x3180 net/core/dev.c:4742
#6: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#6: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#6: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x185/0x1840 net/bridge/br_device.c:52
#7: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:918 [inline]
#7: ffffffff8df3d740 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2ab/0x3180 net/core/dev.c:4742
#8: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#8: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#8: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: hsr_dev_xmit+0x2d/0x360 net/hsr/hsr_device.c:229
stack backtrace:
CPU: 0 UID: 0 PID: 5837 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3041
check_deadlock kernel/locking/lockdep.c:3093 [inline]
validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3895
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
__netdev_start_xmit include/linux/netdevice.h:5259 [inline]
netdev_start_xmit include/linux/netdevice.h:5268 [inline]
xmit_one net/core/dev.c:3853 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3869
__dev_queue_xmit+0x14c5/0x3180 net/core/dev.c:4817
dev_queue_xmit include/linux/netdevice.h:3368 [inline]
br_dev_queue_push_xmit+0x6c5/0x890 net/bridge/br_forward.c:53
NF_HOOK+0x320/0x3c0 include/linux/netfilter.h:318
br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
NF_HOOK+0x320/0x3c0 include/linux/netfilter.h:318
__br_forward+0x41e/0x600 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver+0xb5/0x160 net/bridge/br_forward.c:191
br_flood+0x31a/0x6a0 net/bridge/br_forward.c:238
br_dev_xmit+0x11b3/0x1840 net/bridge/br_device.c:108
__netdev_start_xmit include/linux/netdevice.h:5259 [inline]
netdev_start_xmit include/linux/netdevice.h:5268 [inline]
xmit_one net/core/dev.c:3853 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3869
__dev_queue_xmit+0x14c5/0x3180 net/core/dev.c:4817
dev_queue_xmit include/linux/netdevice.h:3368 [inline]
hsr_xmit net/hsr/hsr_forward.c:438 [inline]
hsr_forward_do net/hsr/hsr_forward.c:579 [inline]
hsr_forward_skb+0x158b/0x2860 net/hsr/hsr_forward.c:741
send_hsr_supervision_frame+0x731/0xcb0 net/hsr/hsr_device.c:364
hsr_announce+0x1d5/0x360 net/hsr/hsr_device.c:421
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404
handle_softirqs+0x286/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:list_empty include/linux/list.h:381 [inline]
RIP: 0010:node_pool_del_va mm/vmalloc.c:1935 [inline]
RIP: 0010:node_alloc mm/vmalloc.c:1986 [inline]
RIP: 0010:alloc_vmap_area+0xe5f/0x14c0 mm/vmalloc.c:2041
Code: 0f 85 97 01 00 00 4c 89 f7 c1 eb 0c 0f b6 c3 48 8d 04 40 49 8d 04 c6 48 89 44 24 10 48 85 c0 0f 84 78 01 00 00 48 8b 5c 24 10 <48> c1 eb 03 48 b8 00 00 00 00 00 fc ff df 80 3c 03 00 74 10 49 89
RSP: 0018:ffffc9000436f3e0 EFLAGS: 00000286
RAX: ffff88801a040018 RBX: ffff88801a040018 RCX: ffff8880323c5ac0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88801a040000
RBP: ffffc9000436f518 R08: 00000000ffffffff R09: 0000000000000dc0
R10: 000000000000000e R11: ffffffff81ac2e10 R12: ffffc90000000000
R13: ffffe8ffffffffff R14: ffff88801a040000 R15: 0000000000000000
__get_vm_area_node+0x1f8/0x300 mm/vmalloc.c:3193
__vmalloc_node_range_noprof+0x30c/0x12d0 mm/vmalloc.c:3857
__vmalloc_node_noprof mm/vmalloc.c:3960 [inline]
vzalloc_noprof+0xb2/0xf0 mm/vmalloc.c:4034
alloc_counters+0xd3/0x6d0 net/ipv4/netfilter/ip_tables.c:799
copy_entries_to_user net/ipv4/netfilter/ip_tables.c:821 [inline]
get_entries net/ipv4/netfilter/ip_tables.c:1022 [inline]
do_ipt_get_ctl+0xaac/0x1180 net/ipv4/netfilter/ip_tables.c:1668
nf_getsockopt+0x26e/0x290 net/netfilter/nf_sockopt.c:116
ip_getsockopt+0x1c4/0x220 net/ipv4/ip_sockglue.c:1777
do_sock_getsockopt+0x372/0x450 net/socket.c:2421
__sys_getsockopt net/socket.c:2450 [inline]
__do_sys_getsockopt net/socket.c:2457 [inline]
__se_sys_getsockopt net/socket.c:2454 [inline]
__x64_sys_getsockopt+0x1a5/0x250 net/socket.c:2454
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc245b9148a
Code: ff c3 66 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b8 0f 1f 44 00 00 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 a8 ff ff ff f7
RSP: 002b:00007ffd5f9fe648 EFLAGS: 00000216 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007ffd5f9fe6d0 RCX: 00007fc245b9148a
RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffd5f9fe66c R09: 00007ffd5f9fea87
R10: 00007ffd5f9fe6d0 R11: 0000000000000216 R12: 00007fc245db7e60
R13: 00007ffd5f9fe66c R14: 0000000000000000 R15: 00007fc245dba020
----------------
Code disassembly (best guess):
0: 0f 85 97 01 00 00 jne 0x19d
6: 4c 89 f7 mov %r14,%rdi
9: c1 eb 0c shr $0xc,%ebx
c: 0f b6 c3 movzbl %bl,%eax
f: 48 8d 04 40 lea (%rax,%rax,2),%rax
13: 49 8d 04 c6 lea (%r14,%rax,8),%rax
17: 48 89 44 24 10 mov %rax,0x10(%rsp)
1c: 48 85 c0 test %rax,%rax
1f: 0f 84 78 01 00 00 je 0x19d
25: 48 8b 5c 24 10 mov 0x10(%rsp),%rbx
* 2a: 48 c1 eb 03 shr $0x3,%rbx <-- trapping instruction
2e: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
35: fc ff df
38: 80 3c 03 00 cmpb $0x0,(%rbx,%rax,1)
3c: 74 10 je 0x4e
3e: 49 rex.WB
3f: 89 .byte 0x89