============================================
WARNING: possible recursive locking detected
6.16.0-rc4-syzkaller-01191-gc65d34296b22 #0 Not tainted
--------------------------------------------
syz.1.1296/10470 is trying to acquire lock:
ffff88807ba78f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88807ba78f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234
but task is already holding lock:
ffff888073b02f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff888073b02f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234
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
12 locks held by syz.1.1296/10470:
#0: ffff8880324bc260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:356 [inline]
#0: ffff8880324bc260 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x28e/0xb50 mm/mmap.c:1292
#1: ffffc90000a08be0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbe/0x5f0 kernel/time/timer.c:1744
#2: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#2: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: ndisc_send_skb+0x20c/0x1440 net/ipv6/ndisc.c:486
#3: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: ip6_finish_output2+0x701/0x16a0 net/ipv6/ip6_output.c:126
#4: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#4: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#4: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4637
#5: ffff888073b02f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#5: ffff888073b02f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234
#6: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#6: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#6: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0x9e/0x2860 net/hsr/hsr_forward.c:728
#7: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#7: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4637
#8: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#8: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#8: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: bond_start_xmit+0xf8/0x1a10 drivers/net/bonding/bond_main.c:5675
#9: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#9: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#9: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4637
#10: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#10: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#10: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x185/0x1840 net/bridge/br_device.c:52
#11: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#11: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#11: ffffffff8e13ee80 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27b/0x3b50 net/core/dev.c:4637
stack backtrace:
CPU: 1 UID: 0 PID: 10470 Comm: syz.1.1296 Not tainted 6.16.0-rc4-syzkaller-01191-gc65d34296b22 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3044
check_deadlock kernel/locking/lockdep.c:3096 [inline]
validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3898
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
__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+0x19a/0x220 net/hsr/hsr_device.c:234
__netdev_start_xmit include/linux/netdevice.h:5217 [inline]
netdev_start_xmit include/linux/netdevice.h:5226 [inline]
xmit_one net/core/dev.c:3826 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3842
__dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4712
dev_queue_xmit include/linux/netdevice.h:3358 [inline]
br_dev_queue_push_xmit+0x6c5/0x890 net/bridge/br_forward.c:53
NF_HOOK+0x31d/0x3c0 include/linux/netfilter.h:317
br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66
NF_HOOK+0x31d/0x3c0 include/linux/netfilter.h:317
__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:190
br_flood+0x31a/0x6a0 net/bridge/br_forward.c:237
br_dev_xmit+0x11b3/0x1840 net/bridge/br_device.c:108
__netdev_start_xmit include/linux/netdevice.h:5217 [inline]
netdev_start_xmit include/linux/netdevice.h:5226 [inline]
xmit_one net/core/dev.c:3826 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3842
__dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4712
__bond_start_xmit include/linux/netdevice.h:-1 [inline]
bond_start_xmit+0xdc7/0x1a10 drivers/net/bonding/bond_main.c:5677
__netdev_start_xmit include/linux/netdevice.h:5217 [inline]
netdev_start_xmit include/linux/netdevice.h:5226 [inline]
xmit_one net/core/dev.c:3826 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3842
__dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4712
dev_queue_xmit include/linux/netdevice.h:3358 [inline]
hsr_xmit net/hsr/hsr_forward.c:430 [inline]
hsr_forward_do net/hsr/hsr_forward.c:571 [inline]
hsr_forward_skb+0x158b/0x2860 net/hsr/hsr_forward.c:733
hsr_dev_xmit+0x1a5/0x220 net/hsr/hsr_device.c:235
__netdev_start_xmit include/linux/netdevice.h:5217 [inline]
netdev_start_xmit include/linux/netdevice.h:5226 [inline]
xmit_one net/core/dev.c:3826 [inline]
dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3842
__dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4712
neigh_output include/net/neighbour.h:542 [inline]
ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226
NF_HOOK include/linux/netfilter.h:317 [inline]
ndisc_send_skb+0xb54/0x1440 net/ipv6/ndisc.c:516
addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4037
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x286/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:246 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x18/0x90 kernel/kcov.c:300
Code: 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 d0 a0 92 65 8b 0d 18 6d e0 10 <81> e1 00 01 ff 00 74 11 81 f9 00 01 00 00 75 5b 83 ba 3c 16 00 00
RSP: 0018:ffffc90004faf3b8 EFLAGS: 00000246
RAX: ffffffff81fbf782 RBX: 0000000000000000 RCX: 0000000080000000
RDX: ffff88807a163c00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004faf4b0 R08: ffffea0001a800f7 R09: 1ffffd400035001e
R10: dffffc0000000000 R11: fffff9400035001f R12: 0000000000000000
R13: ffffea0001a800c0 R14: 0000000000000017 R15: 0200000000000000
folios_put_refs+0x252/0x640 mm/swap.c:964
free_pages_and_swap_cache+0x277/0x520 mm/swap_state.c:264
__tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
exit_mmap+0x44c/0xb50 mm/mmap.c:1297
__mmput+0x118/0x420 kernel/fork.c:1121
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x22e0 kernel/exit.c:952
do_group_exit+0x21c/0x2d0 kernel/exit.c:1105
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7ee498e929
Code: Unable to access opcode bytes at 0x7f7ee498e8ff.
RSP: 002b:00007f7ee572d0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f7ee4bb5fa8 RCX: 00007f7ee498e929
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7ee4bb5fa8
RBP: 00007f7ee4bb5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7ee4bb5fac
R13: 0000000000000000 R14: 00007fffbc713a70 R15: 00007fffbc713b58
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
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: f3 0f 1e fa endbr64
16: 48 8b 04 24 mov (%rsp),%rax
1a: 65 48 8b 14 25 08 d0 mov %gs:0xffffffff92a0d008,%rdx
21: a0 92
23: 65 8b 0d 18 6d e0 10 mov %gs:0x10e06d18(%rip),%ecx # 0x10e06d42
* 2a: 81 e1 00 01 ff 00 and $0xff0100,%ecx <-- trapping instruction
30: 74 11 je 0x43
32: 81 f9 00 01 00 00 cmp $0x100,%ecx
38: 75 5b jne 0x95
3a: 83 .byte 0x83
3b: ba 3c 16 00 00 mov $0x163c,%edx