============================================
WARNING: possible recursive locking detected
syzkaller #0 Tainted: G L
--------------------------------------------
udevd/6595 is trying to acquire lock:
ffff88807a4ccf70 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline]
ffff88807a4ccf70 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
but task is already holding lock:
ffff888076a52f70 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline]
ffff888076a52f70 (&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
11 locks held by udevd/6595:
#0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: path_init+0x124/0x1330 fs/namei.c:2680
#1: ffffc90000007ce0 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xd4/0x640 kernel/time/timer.c:1745
#2: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#2: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#2: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: hsr_announce+0x89/0x370 net/hsr/hsr_device.c:419
#3: ffff888076a52f70 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:347 [inline]
#3: ffff888076a52f70 (&hsr->seqnr_lock){+.-.}-{3:3}, at: send_hsr_supervision_frame+0x380/0xcb0 net/hsr/hsr_device.c:330
#4: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#4: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#4: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0xb3/0x2860 net/hsr/hsr_forward.c:738
#5: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#5: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:903 [inline]
#5: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x277/0x3890 net/core/dev.c:4761
#6: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#6: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#6: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: bond_start_xmit+0xc9/0x1960 drivers/net/bonding/bond_main.c:5589
#7: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:903 [inline]
#7: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x277/0x3890 net/core/dev.c:4761
#8: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#8: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#8: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x193/0x1980 net/bridge/br_device.c:52
#9: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#9: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:903 [inline]
#9: ffffffff8e75e4c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x277/0x3890 net/core/dev.c:4761
#10: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#10: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#10: ffffffff8e75e460 (rcu_read_lock){....}-{1:3}, at: hsr_dev_xmit+0x2d/0x360 net/hsr/hsr_device.c:229
stack backtrace:
CPU: 0 UID: 0 PID: 6595 Comm: udevd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_deadlock_bug+0x279/0x290 kernel/locking/lockdep.c:3041
check_deadlock kernel/locking/lockdep.c:3093 [inline]
validate_chain kernel/locking/lockdep.c:3895 [inline]
__lock_acquire+0x253f/0x2cf0 kernel/locking/lockdep.c:5237
lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:150 [inline]
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:347 [inline]
hsr_dev_xmit+0x237/0x360 net/hsr/hsr_device.c:235
__netdev_start_xmit include/linux/netdevice.h:5324 [inline]
netdev_start_xmit include/linux/netdevice.h:5333 [inline]
xmit_one net/core/dev.c:3871 [inline]
dev_hard_start_xmit+0x2d8/0x870 net/core/dev.c:3887
__dev_queue_xmit+0x16d1/0x3890 net/core/dev.c:4837
dev_queue_xmit include/linux/netdevice.h:3384 [inline]
br_dev_queue_push_xmit+0x370/0x4a0 net/bridge/br_forward.c:53
NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318
br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
NF_HOOK+0x360/0x3f0 include/linux/netfilter.h:318
__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+0x6ee/0xb80 net/bridge/br_forward.c:238
br_dev_xmit+0x12bd/0x1980 net/bridge/br_device.c:108
__netdev_start_xmit include/linux/netdevice.h:5324 [inline]
netdev_start_xmit include/linux/netdevice.h:5333 [inline]
xmit_one net/core/dev.c:3871 [inline]
dev_hard_start_xmit+0x2d8/0x870 net/core/dev.c:3887
__dev_queue_xmit+0x16d1/0x3890 net/core/dev.c:4837
__bond_start_xmit drivers/net/bonding/bond_main.c:-1 [inline]
bond_start_xmit+0xd6e/0x1960 drivers/net/bonding/bond_main.c:5591
__netdev_start_xmit include/linux/netdevice.h:5324 [inline]
netdev_start_xmit include/linux/netdevice.h:5333 [inline]
xmit_one net/core/dev.c:3871 [inline]
dev_hard_start_xmit+0x2d8/0x870 net/core/dev.c:3887
__dev_queue_xmit+0x16d1/0x3890 net/core/dev.c:4837
dev_queue_xmit include/linux/netdevice.h:3384 [inline]
hsr_xmit net/hsr/hsr_forward.c:440 [inline]
hsr_forward_do net/hsr/hsr_forward.c:581 [inline]
hsr_forward_skb+0x157b/0x2860 net/hsr/hsr_forward.c:743
send_hsr_supervision_frame+0x731/0xcb0 net/hsr/hsr_device.c:364
hsr_announce+0x1db/0x370 net/hsr/hsr_device.c:421
call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:98 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline]
RIP: 0010:kasan_check_range+0x97/0x2c0 mm/kasan/generic.c:200
Code: 00 fc ff df 4d 8d 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 <0f> 85 9e 01 00 00 49 ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd
RSP: 0018:ffffc9000c0df840 EFLAGS: 00000246
RAX: ffffffff82472201 RBX: ffffffffffffffff RCX: ffffffff8247235d
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc9000c0dfaa0
RBP: 0000000000000100 R08: ffffc9000c0dfaaf R09: 1ffff9200181bf55
R10: dffffc0000000000 R11: fffff5200181bf55 R12: 0000000000000002
R13: 1ffff9200181bf5b R14: fffff5200181bf56 R15: 1ffff9200181bf54
__asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
nd_jump_root+0x1cd/0x430 fs/namei.c:1143
path_init+0x433/0x1330 fs/namei.c:2711
path_lookupat+0x2a/0x8c0 fs/namei.c:2794
filename_lookup+0x256/0x5d0 fs/namei.c:2833
vfs_statx+0xfc/0x200 fs/stat.c:353
vfs_fstatat+0x11b/0x170 fs/stat.c:373
__do_sys_newfstatat fs/stat.c:538 [inline]
__se_sys_newfstatat fs/stat.c:532 [inline]
__x64_sys_newfstatat+0x151/0x200 fs/stat.c:532
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3438a46b0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007ffd88249548 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffd882499e0 RCX: 00007f3438a46b0a
RDX: 00007ffd88249550 RSI: 00007ffd882499e0 RDI: 00000000ffffff9c
RBP: 0000562f96da1910 R08: 0000000000000000 R09: 0000000000000020
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd882495e0
R13: 00007ffd88249e15 R14: 0000562f825a1ca4 R15: 0000562f825a1bcc
----------------
Code disassembly (best guess):
0: 00 fc add %bh,%ah
2: ff lcall (bad)
3: df 4d 8d fisttps -0x73(%rbp)
6: 34 19 xor $0x19,%al
8: 4d 89 f4 mov %r14,%r12
b: 4d 29 dc sub %r11,%r12
e: 49 83 fc 10 cmp $0x10,%r12
12: 7f 29 jg 0x3d
14: 4d 85 e4 test %r12,%r12
17: 0f 84 3d 01 00 00 je 0x15a
1d: 4c 89 cb mov %r9,%rbx
20: 48 f7 d3 not %rbx
23: 4c 01 fb add %r15,%rbx
26: 41 80 3b 00 cmpb $0x0,(%r11)
* 2a: 0f 85 9e 01 00 00 jne 0x1ce <-- trapping instruction
30: 49 ff c3 inc %r11
33: 48 ff c3 inc %rbx
36: 75 ee jne 0x26
38: e9 1d 01 00 00 jmp 0x15a
3d: 44 89 dd mov %r11d,%ebp