============================================ WARNING: possible recursive locking detected 5.16.0-rc4-syzkaller #0 Not tainted -------------------------------------------- syz-executor.0/17133 is trying to acquire lock: ffff888049109330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] ffff888049109330 (&br->multicast_lock){+.-.}-{2:2}, at: br_ip6_multicast_query net/bridge/br_multicast.c:3341 [inline] ffff888049109330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_ipv6_rcv net/bridge/br_multicast.c:3737 [inline] ffff888049109330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_rcv+0x16dc/0x6230 net/bridge/br_multicast.c:3792 but task is already holding lock: ffff8880751c9330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] ffff8880751c9330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x61/0x360 net/bridge/br_multicast.c:1742 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&br->multicast_lock); lock(&br->multicast_lock); *** DEADLOCK *** May be due to missing lock nesting notation 10 locks held by syz-executor.0/17133: #0: ffff88807d461628 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] #0: ffff88807d461628 (&mm->mmap_lock#2){++++}-{3:3}, at: __mm_populate+0x264/0x3e0 mm/gup.c:1581 #1: ffffc90000dc0d70 ((&pmctx->ip6_own_query.timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:35 [inline] #1: ffffc90000dc0d70 ((&pmctx->ip6_own_query.timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 kernel/time/timer.c:1411 #2: ffff8880751c9330 (&br->multicast_lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] #2: ffff8880751c9330 (&br->multicast_lock){+.-.}-{2:2}, at: br_multicast_port_query_expired+0x61/0x360 net/bridge/br_multicast.c:1742 #3: ffffffff8bb83cc0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3650 net/core/dev.c:4153 #4: ffffffff8bb83d20 (rcu_read_lock){....}-{1:2}, at: is_netpoll_tx_blocked include/net/bonding.h:109 [inline] #4: ffffffff8bb83d20 (rcu_read_lock){....}-{1:2}, at: bond_start_xmit+0x88/0x1220 drivers/net/bonding/bond_main.c:5091 #5: ffffffff8bb83cc0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3650 net/core/dev.c:4153 #6: ffffffff8bb83d20 (rcu_read_lock){....}-{1:2}, at: is_netpoll_tx_blocked include/net/bonding.h:109 [inline] #6: ffffffff8bb83d20 (rcu_read_lock){....}-{1:2}, at: bond_start_xmit+0x88/0x1220 drivers/net/bonding/bond_main.c:5091 #7: ffffffff8bb83cc0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3650 net/core/dev.c:4153 #8: ffffffff8bb83cc0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x1e3/0x3650 net/core/dev.c:4153 #9: ffffffff8bb83d20 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0x0/0x16c0 net/bridge/br_device.c:309 stack backtrace: CPU: 1 PID: 17133 Comm: syz-executor.0 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] br_ip6_multicast_query net/bridge/br_multicast.c:3341 [inline] br_multicast_ipv6_rcv net/bridge/br_multicast.c:3737 [inline] br_multicast_rcv+0x16dc/0x6230 net/bridge/br_multicast.c:3792 br_dev_xmit+0x6f6/0x16c0 net/bridge/br_device.c:89 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229 vlan_dev_hard_start_xmit+0x1b3/0x670 net/8021q/vlan_dev.c:124 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229 bond_dev_queue_xmit+0xc3/0x170 drivers/net/bonding/bond_main.c:304 bond_do_alb_xmit+0x5c1/0x8a0 drivers/net/bonding/bond_alb.c:1325 __bond_start_xmit drivers/net/bonding/bond_main.c:5072 [inline] bond_start_xmit+0xaad/0x1220 drivers/net/bonding/bond_main.c:5096 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229 bond_dev_queue_xmit+0xc3/0x170 drivers/net/bonding/bond_main.c:304 bond_3ad_xor_xmit drivers/net/bonding/bond_main.c:4834 [inline] __bond_start_xmit drivers/net/bonding/bond_main.c:5068 [inline] bond_start_xmit+0xb01/0x1220 drivers/net/bonding/bond_main.c:5096 __netdev_start_xmit include/linux/netdevice.h:4994 [inline] netdev_start_xmit include/linux/netdevice.h:5008 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606 __dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229 br_dev_queue_push_xmit+0x25a/0x740 net/bridge/br_forward.c:53 NF_HOOK include/linux/netfilter.h:307 [inline] __br_multicast_send_query+0x118d/0x3aa0 net/bridge/br_multicast.c:1646 br_multicast_send_query+0x266/0x4b0 net/bridge/br_multicast.c:1725 br_multicast_port_query_expired+0x2c3/0x360 net/bridge/br_multicast.c:1750 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 0f 1f 44 00 00 55 48 8b 74 24 08 48 89 fd 48 83 c7 18 e8 6e a1 15 f8 48 89 ef e8 b6 17 16 f8 e8 31 d2 36 f8 fb bf 01 00 00 00 06 e0 08 f8 65 8b 05 df 52 bb 76 85 c0 74 02 5d c3 e8 fb 27 b9 RSP: 0018:ffffc9000311f668 EFLAGS: 00000206 RAX: 000000000000c699 RBX: 0000000000000001 RCX: 1ffffffff1ff0d96 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff8880756528a8 R08: 0000000000000001 R09: ffffffff8ff73a37 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000001 R14: ffffea000142fa80 R15: ffffc9000311f708 spin_unlock_irq include/linux/spinlock.h:399 [inline] shmem_add_to_page_cache+0xeff/0x15d0 mm/shmem.c:746 shmem_getpage_gfp+0x838/0x22d0 mm/shmem.c:1936 shmem_fault+0x1b4/0x750 mm/shmem.c:2114 __do_fault+0x10d/0x4d0 mm/memory.c:3849 do_read_fault mm/memory.c:4164 [inline] do_fault mm/memory.c:4293 [inline] handle_pte_fault mm/memory.c:4551 [inline] __handle_mm_fault+0x28e8/0x5120 mm/memory.c:4686 handle_mm_fault+0x1c8/0x790 mm/memory.c:4784 faultin_page mm/gup.c:939 [inline] __get_user_pages+0x522/0xfb0 mm/gup.c:1160 populate_vma_page_range+0x24d/0x330 mm/gup.c:1492 __mm_populate+0x1ea/0x3e0 mm/gup.c:1601 mm_populate include/linux/mm.h:2734 [inline] vm_mmap_pgoff+0x20e/0x290 mm/util.c:524 ksys_mmap_pgoff+0x79/0x5a0 mm/mmap.c:1623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fb0cb8cce99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb0ca221168 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007fb0cb9e0030 RCX: 00007fb0cb8cce99 RDX: 0000000000000003 RSI: 0000000000b36000 RDI: 0000000020000000 RBP: 00007fb0cb926ff1 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffda6e381bf R14: 00007fb0ca221300 R15: 0000000000022000 vcan0: j1939_xtp_rx_abort_one: 0xffff88805687b800: 0x00000: (2) System resources were needed for another task so this connection managed session was terminated. vcan0: j1939_xtp_rx_abort_one: 0xffff8880457c0c00: 0x00000: (2) System resources were needed for another task so this connection managed session was terminated. vcan0: j1939_xtp_rx_abort_one: 0xffff88805dac2400: 0x00000: (2) System resources were needed for another task so this connection managed session was terminated. ---------------- Code disassembly (best guess): 0: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 5: 55 push %rbp 6: 48 8b 74 24 08 mov 0x8(%rsp),%rsi b: 48 89 fd mov %rdi,%rbp e: 48 83 c7 18 add $0x18,%rdi 12: e8 6e a1 15 f8 callq 0xf815a185 17: 48 89 ef mov %rbp,%rdi 1a: e8 b6 17 16 f8 callq 0xf81617d5 1f: e8 31 d2 36 f8 callq 0xf836d255 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 06 e0 08 f8 callq 0xf808e035 <-- trapping instruction 2f: 65 8b 05 df 52 bb 76 mov %gs:0x76bb52df(%rip),%eax # 0x76bb5315 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5d pop %rbp 3b: c3 retq 3c: e8 .byte 0xe8 3d: fb sti 3e: 27 (bad) 3f: b9 .byte 0xb9