============================================ WARNING: possible recursive locking detected 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Not tainted -------------------------------------------- udevd/4523 is trying to acquire lock: ffff888063626da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888063626da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: hsr_dev_xmit+0x13e/0x1d0 net/hsr/hsr_device.c:229 but task is already holding lock: ffff88807eb60da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88807eb60da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x276/0xad0 net/hsr/hsr_device.c:310 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 8 locks held by udevd/4523: #0: ffff888078392ee0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:803 [inline] #0: ffff888078392ee0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: open_last_lookups fs/namei.c:3565 [inline] #0: ffff888078392ee0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: path_openat+0x7c4/0x3240 fs/namei.c:3796 #1: ffffc90000007c00 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1789 #2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #2: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hsr_announce+0xa3/0x370 net/hsr/hsr_device.c:387 #3: ffff88807eb60da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #3: ffff88807eb60da0 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x276/0xad0 net/hsr/hsr_device.c:310 #4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #4: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hsr_forward_skb+0xae/0x2400 net/hsr/hsr_forward.c:614 #5: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #5: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline] #5: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260 #6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #6: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0x1b9/0x1a10 net/bridge/br_device.c:44 #7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline] #7: ffffffff8e132080 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4260 stack backtrace: CPU: 0 PID: 4523 Comm: udevd Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_deadlock kernel/locking/lockdep.c:3062 [inline] validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __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+0x13e/0x1d0 net/hsr/hsr_device.c:229 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547 __dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] br_dev_queue_push_xmit+0x701/0x8d0 net/bridge/br_forward.c:53 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 br_forward_finish+0xe5/0x140 net/bridge/br_forward.c:66 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 __br_forward+0x489/0x660 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+0x2e4/0x660 net/bridge/br_forward.c:236 br_dev_xmit+0x118c/0x1a10 __netdev_start_xmit include/linux/netdevice.h:4903 [inline] netdev_start_xmit include/linux/netdevice.h:4917 [inline] xmit_one net/core/dev.c:3531 [inline] dev_hard_start_xmit+0x26a/0x790 net/core/dev.c:3547 __dev_queue_xmit+0x19f4/0x3b10 net/core/dev.c:4335 dev_queue_xmit include/linux/netdevice.h:3091 [inline] hsr_xmit net/hsr/hsr_forward.c:380 [inline] hsr_forward_do net/hsr/hsr_forward.c:471 [inline] hsr_forward_skb+0x183f/0x2400 net/hsr/hsr_forward.c:619 send_hsr_supervision_frame+0x548/0xad0 net/hsr/hsr_device.c:333 hsr_announce+0x1a9/0x370 net/hsr/hsr_device.c:389 call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2408 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419 run_timer_base kernel/time/timer.c:2428 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:find_stack lib/stackdepot.c:593 [inline] RIP: 0010:stack_depot_save_flags+0x15f/0x860 lib/stackdepot.c:659 Code: de c1 c3 18 41 29 de 48 8b 05 2d 73 9f 0f 8b 0d 1f 73 9f 0f 44 21 f1 48 c1 e1 04 48 8d 14 08 65 ff 05 ad ba 24 7b 4c 8b 3c 08 <49> 39 d7 8b 6c 24 0c 0f 84 95 00 00 00 45 89 cd eb 0c 4d 8b 3f 49 RSP: 0018:ffffc90003187400 EFLAGS: 00000282 RAX: ffff88823ac00000 RBX: 0000000033eb4c62 RCX: 00000000002f38a0 RDX: ffff88823aef38a0 RSI: 0000000000000001 RDI: 00000000922f4ab0 RBP: 000000000c22e98f R08: ffffc90003187460 R09: 000000000000000b R10: dffffc0000000000 R11: fffffbfff1f0e59e R12: 0000000000000000 R13: ffff888015aeb8c0 R14: 00000000e9e2f38a R15: ffff88802e6db740 kasan_save_stack mm/kasan/common.c:48 [inline] kasan_save_track+0x51/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_lru+0x178/0x350 mm/slub.c:3864 __d_alloc+0x31/0x700 fs/dcache.c:1624 d_alloc fs/dcache.c:1704 [inline] d_alloc_parallel+0xdf/0x1600 fs/dcache.c:2462 lookup_open fs/namei.c:3422 [inline] open_last_lookups fs/namei.c:3566 [inline] path_openat+0x924/0x3240 fs/namei.c:3796 do_filp_open+0x235/0x490 fs/namei.c:3826 do_sys_openat2+0x13e/0x1d0 fs/open.c:1406 do_sys_open fs/open.c:1421 [inline] __do_sys_openat fs/open.c:1437 [inline] __se_sys_openat fs/open.c:1432 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1432 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f051c9169a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc48088b10 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f051c9169a4 RDX: 0000000000080000 RSI: 00007ffc48088c48 RDI: 00000000ffffff9c RBP: 00007ffc48088c48 R08: 0000000000000008 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000 R13: 000056012a9ccb42 R14: 0000000000000001 R15: 0000000000000000 ---------------- Code disassembly (best guess): 0: de c1 faddp %st,%st(1) 2: c3 ret 3: 18 41 29 sbb %al,0x29(%rcx) 6: de 48 8b fimuls -0x75(%rax) 9: 05 2d 73 9f 0f add $0xf9f732d,%eax e: 8b 0d 1f 73 9f 0f mov 0xf9f731f(%rip),%ecx # 0xf9f7333 14: 44 21 f1 and %r14d,%ecx 17: 48 c1 e1 04 shl $0x4,%rcx 1b: 48 8d 14 08 lea (%rax,%rcx,1),%rdx 1f: 65 ff 05 ad ba 24 7b incl %gs:0x7b24baad(%rip) # 0x7b24bad3 26: 4c 8b 3c 08 mov (%rax,%rcx,1),%r15 * 2a: 49 39 d7 cmp %rdx,%r15 <-- trapping instruction 2d: 8b 6c 24 0c mov 0xc(%rsp),%ebp 31: 0f 84 95 00 00 00 je 0xcc 37: 45 89 cd mov %r9d,%r13d 3a: eb 0c jmp 0x48 3c: 4d 8b 3f mov (%r15),%r15 3f: 49 rex.WB