============================================
WARNING: possible recursive locking detected
6.14.0-syzkaller-13305-g61f96e684edd #0 Not tainted
--------------------------------------------
syz-executor/5852 is trying to acquire lock:
ffff88807f2c2f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88807f2c2f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x18a/0x210 net/hsr/hsr_device.c:234
but task is already holding lock:
ffff88801bf56f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff88801bf56f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x18a/0x210 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
13 locks held by syz-executor/5852:
#0: ffffffff8edf6170 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1733 [inline]
#0: ffffffff8edf6170 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x1d6/0x22c0 kernel/fork.c:1786
#1: ffff8880626e01e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:146 [inline]
#1: ffff8880626e01e0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap kernel/fork.c:620 [inline]
#1: ffff8880626e01e0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mm kernel/fork.c:1734 [inline]
#1: ffff8880626e01e0 (&mm->mmap_lock){++++}-{4:4}, at: copy_mm+0x2a8/0x22c0 kernel/fork.c:1786
#2: ffff8880128001e0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:136 [inline]
#2: ffff8880128001e0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap kernel/fork.c:627 [inline]
#2: ffff8880128001e0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mm kernel/fork.c:1734 [inline]
#2: ffff8880128001e0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: copy_mm+0x449/0x22c0 kernel/fork.c:1786
#3: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
#3: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xb8/0x23b0 arch/x86/kernel/unwind_orc.c:479
#4: ffffc90000007bc0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc2/0x650 kernel/time/timer.c:1786
#5: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#5: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#5: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: ndisc_send_skb+0x1ef/0x1560 net/ipv6/ndisc.c:484
#6: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#6: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#6: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: ip6_finish_output2+0x701/0x1750 net/ipv6/ip6_output.c:126
#7: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#7: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#7: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2f9/0x3f60 net/core/dev.c:4561
#8: ffff88801bf56f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#8: ffff88801bf56f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x18a/0x210 net/hsr/hsr_device.c:234
#9: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#9: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#9: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0xb8/0x2d20 net/hsr/hsr_forward.c:728
#10: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#10: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#10: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2f9/0x3f60 net/core/dev.c:4561
#11: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#11: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#11: ffffffff8ed3dfe0 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x220/0x1c00 net/bridge/br_device.c:52
#12: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
#12: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline]
#12: ffffffff8ed3e040 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x2f9/0x3f60 net/core/dev.c:4561
stack backtrace:
CPU: 0 UID: 0 PID: 5852 Comm: syz-executor Not tainted 6.14.0-syzkaller-13305-g61f96e684edd #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
print_deadlock_bug+0x2be/0x2d0 kernel/locking/lockdep.c:3042
check_deadlock kernel/locking/lockdep.c:3094 [inline]
validate_chain+0x928/0x24e0 kernel/locking/lockdep.c:3896
__lock_acquire+0xad5/0xd80 kernel/locking/lockdep.c:5235
lock_acquire+0x116/0x2f0 kernel/locking/lockdep.c:5866
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
hsr_dev_xmit+0x18a/0x210 net/hsr/hsr_device.c:234
__netdev_start_xmit include/linux/netdevice.h:5201 [inline]
netdev_start_xmit include/linux/netdevice.h:5210 [inline]
xmit_one net/core/dev.c:3783 [inline]
dev_hard_start_xmit+0x2d4/0x840 net/core/dev.c:3799
__dev_queue_xmit+0x1b80/0x3f60 net/core/dev.c:4636
dev_queue_xmit include/linux/netdevice.h:3350 [inline]
br_dev_queue_push_xmit+0x771/0x950 net/bridge/br_forward.c:53
NF_HOOK+0x3ac/0x460 include/linux/netfilter.h:314
br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66
NF_HOOK+0x3ac/0x460 include/linux/netfilter.h:314
__br_forward+0x46a/0x640 net/bridge/br_forward.c:115
deliver_clone net/bridge/br_forward.c:131 [inline]
maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190
br_flood+0x2e4/0x680 net/bridge/br_forward.c:237
br_dev_xmit+0x12ac/0x1c00 net/bridge/br_device.c:-1
__netdev_start_xmit include/linux/netdevice.h:5201 [inline]
netdev_start_xmit include/linux/netdevice.h:5210 [inline]
xmit_one net/core/dev.c:3783 [inline]
dev_hard_start_xmit+0x2d4/0x840 net/core/dev.c:3799
__dev_queue_xmit+0x1b80/0x3f60 net/core/dev.c:4636
dev_queue_xmit include/linux/netdevice.h:3350 [inline]
hsr_xmit net/hsr/hsr_forward.c:430 [inline]
hsr_forward_do net/hsr/hsr_forward.c:571 [inline]
hsr_forward_skb+0x184c/0x2d20 net/hsr/hsr_forward.c:733
hsr_dev_xmit+0x195/0x210 net/hsr/hsr_device.c:235
__netdev_start_xmit include/linux/netdevice.h:5201 [inline]
netdev_start_xmit include/linux/netdevice.h:5210 [inline]
xmit_one net/core/dev.c:3783 [inline]
dev_hard_start_xmit+0x2d4/0x840 net/core/dev.c:3799
__dev_queue_xmit+0x1b80/0x3f60 net/core/dev.c:4636
neigh_output include/net/neighbour.h:539 [inline]
ip6_finish_output2+0x1296/0x1750 net/ipv6/ip6_output.c:141
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x421/0x840 net/ipv6/ip6_output.c:226
NF_HOOK include/linux/netfilter.h:314 [inline]
ndisc_send_skb+0xb58/0x1560 net/ipv6/ndisc.c:513
addrconf_rs_timer+0x380/0x680 net/ipv6/addrconf.c:4037
call_timer_fn+0x189/0x650 kernel/time/timer.c:1789
expire_timers kernel/time/timer.c:1840 [inline]
__run_timers kernel/time/timer.c:2414 [inline]
__run_timer_base+0x66e/0x8e0 kernel/time/timer.c:2426
run_timer_base kernel/time/timer.c:2435 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2445
handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xfb/0x220 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x167/0x2f0 arch/x86/include/asm/irqflags.h:-1
Code: c7 44 24 10 00 00 00 00 9c 8f 44 24 10 f7 44 24 10 00 02 00 00 0f 85 fd 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 65 48 8b 45 00 <48> 3b 44 24 38 0f 85 72 01 00 00 48 83 c4 40 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000407f228 EFLAGS: 00000206
RAX: 148c23f7fbfa0800 RBX: ffffffff8ed3dfe0 RCX: 148c23f7fbfa0800
RDX: 0000000000000000 RSI: ffffffff8e4fce8a RDI: ffffffff8ca1b120
RBP: ffffffff9368a020 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000002 R14: 0000000000000246 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd5/0x23b0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11e/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x11a/0x1d0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4151 [inline]
slab_alloc_node mm/slub.c:4200 [inline]
kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4207
vm_area_dup+0x2b/0x5b0 kernel/fork.c:488
dup_mmap kernel/fork.c:672 [inline]
dup_mm kernel/fork.c:1734 [inline]
copy_mm+0xc70/0x22c0 kernel/fork.c:1786
copy_process+0x17de/0x3d10 kernel/fork.c:2429
kernel_clone+0x242/0x930 kernel/fork.c:2844
__do_sys_clone kernel/fork.c:2987 [inline]
__se_sys_clone kernel/fork.c:2971 [inline]
__x64_sys_clone+0x268/0x2e0 kernel/fork.c:2971
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6c229839d3
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffecbae7628 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6c229839d3
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 0000555563b217d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 000000000003bc42 R15: 00007ffecbae77c0
----------------
Code disassembly (best guess):
0: c7 44 24 10 00 00 00 movl $0x0,0x10(%rsp)
7: 00
8: 9c pushf
9: 8f 44 24 10 pop 0x10(%rsp)
d: f7 44 24 10 00 02 00 testl $0x200,0x10(%rsp)
14: 00
15: 0f 85 fd 00 00 00 jne 0x118
1b: 41 f7 c6 00 02 00 00 test $0x200,%r14d
22: 74 01 je 0x25
24: fb sti
25: 65 48 8b 45 00 mov %gs:0x0(%rbp),%rax
* 2a: 48 3b 44 24 38 cmp 0x38(%rsp),%rax <-- trapping instruction
2f: 0f 85 72 01 00 00 jne 0x1a7
35: 48 83 c4 40 add $0x40,%rsp
39: 5b pop %rbx
3a: 41 5c pop %r12
3c: 41 5d pop %r13
3e: 41 5e pop %r14