syzbot

bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P6797/2:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=19601, q=484 ncpus=2)
task:syz.2.246       state:R  running task     stack:22568 pid:6797  ppid:5776   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7010
 irqentry_exit+0x67/0x70 kernel/entry/common.c:438
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:l3mdev_update_flow+0x4/0x5f0 net/l3mdev/l3mdev.c:272
Code: 03 38 ca 0f 8c 00 ff ff ff 4c 89 f7 89 c5 e8 d3 4b 7e f7 89 e8 e9 ef fe ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa <55> 41 57 41 56 41 55 41 54 53 50 48 89 f3 49 89 ff e8 b6 d6 25 f7
RSP: 0018:ffffc90003426bb8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc90003426da0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffc90003426f20 RDI: ffff88807a84bb80
RBP: ffffc90003426cb8 R08: ffffc90003426c0f R09: 0000000000000000
R10: ffffc90003426c00 R11: fffff52000684d82 R12: ffff88807a84bb80
R13: 1ffff92000684d7c R14: ffffc90003426f20 R15: dffffc0000000000
 __fib_lookup+0xd4/0x210 net/ipv4/fib_rules.c:91
 ip_route_output_key_hash_rcu+0x276/0x2350 net/ipv4/route.c:2787
 ip_route_output_key_hash+0x1f3/0x330 net/ipv4/route.c:2677
 __ip_route_output_key include/net/route.h:134 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2905
 ip_route_output_key include/net/route.h:144 [inline]
 sctp_v4_get_dst+0xc01/0x11d0 net/sctp/protocol.c:508
 sctp_transport_route+0x112/0x2b0 net/sctp/transport.c:457
 sctp_packet_config+0x44c/0xcf0 net/sctp/output.c:103
 sctp_outq_select_transport+0x480/0x590 net/sctp/outqueue.c:869
 sctp_outq_flush_ctrl net/sctp/outqueue.c:903 [inline]
 sctp_outq_flush+0x326/0x3260 net/sctp/outqueue.c:1212
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:-1 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline]
 sctp_do_sm+0x53c4/0x5af0 net/sctp/sm_sideeffect.c:1169
 sctp_primitive_ASSOCIATE+0x95/0xc0 net/sctp/primitive.c:73
 sctp_sendmsg_to_asoc+0x1009/0x17f0 net/sctp/socket.c:1839
 sctp_sendmsg+0x1afa/0x27b0 net/sctp/socket.c:2038
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x61b/0x980 net/socket.c:2595
 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2649
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2687 [inline]
 __se_sys_sendmsg+0x1d0/0x2c0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe0b679de59
RSP: 002b:00007fe0b768a028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fe0b6a25fa0 RCX: 00007fe0b679de59
RDX: 0000000004000040 RSI: 00002000000010c0 RDI: 0000000000000004
RBP: 00007fe0b6833e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe0b6a26038 R14: 00007fe0b6a25fa0 R15: 00007ffda6b30578
 </TASK>
rcu: rcu_preempt kthread starved for 366 jiffies! g19601 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27688 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x15ae/0x4660 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6796 Comm: syz.1.245 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x5c/0x60 kernel/kcov.c:234
Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <c3> 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 15 80 d2 7c 7e 65 8b
RSP: 0018:ffffc90000006ac0 EFLAGS: 00000246
RAX: ffffffff813b5989 RBX: ffffc90000007250 RCX: ffff88802ea5da00
RDX: 0000000000000100 RSI: 0000000000000002 RDI: ffffc90000007250
RBP: ffffc90000006bf8 R08: ffff88802ea5da00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffc90000007140
R13: ffffc90000006ba8 R14: ffffc90000006bb8 R15: dffffc0000000000
FS:  00007f06849e86c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f06849a5ff8 CR3: 000000005a221000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __read_once_word_nocheck+0x9/0x10 include/asm-generic/rwonce.h:66
 deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline]
 unwind_next_frame+0x15d9/0x2990 arch/x86/kernel/unwind_orc.c:585
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 slab_alloc mm/slub.c:3503 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3510 [inline]
 kmem_cache_alloc+0x17e/0x2c0 mm/slub.c:3519
 skb_ext_maybe_cow net/core/skbuff.c:6684 [inline]
 skb_ext_add+0x1b3/0x8e0 net/core/skbuff.c:6758
 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:165 [inline]
 br_nf_forward_ip+0xc6/0x10d0 net/bridge/br_netfilter_hooks.c:709
 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
 nf_hook_slow+0xbd/0x200 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:259 [inline]
 NF_HOOK+0x23e/0x3e0 include/linux/netfilter.h:302
 __br_forward+0x433/0x610 net/bridge/br_forward.c:115
 br_handle_frame_finish+0xf2d/0x15c0 net/bridge/br_input.c:215
 br_nf_hook_thresh+0x3cd/0x4a0 net/bridge/br_netfilter_hooks.c:1184
 br_nf_pre_routing_finish_ipv6+0x9e5/0xd20 net/bridge/br_netfilter_ipv6.c:-1
 NF_HOOK include/linux/netfilter.h:304 [inline]
 br_nf_pre_routing_ipv6+0x34d/0x6a0 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:144 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:277 [inline]
 br_handle_frame+0x1240/0x14d0 net/bridge/br_input.c:424
 __netif_receive_skb_core+0xf94/0x3ab0 net/core/dev.c:5540
 __netif_receive_skb_one_core net/core/dev.c:5644 [inline]
 __netif_receive_skb+0x74/0x290 net/core/dev.c:5760
 process_backlog+0x380/0x710 net/core/dev.c:6088
 __napi_poll+0xbb/0x460 net/core/dev.c:6650
 napi_poll net/core/dev.c:6717 [inline]
 net_rx_action+0x65f/0xcc0 net/core/dev.c:6853
 handle_softirqs+0x27d/0x820 kernel/softirq.c:578
 __do_softirq kernel/softirq.c:612 [inline]
 invoke_softirq kernel/softirq.c:452 [inline]
 __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 4b e4 ce f6 65 8b 05 1c 33 76 75 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90003227200 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 33549039ea756b00
RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: 0000000000000001
RBP: ffffc90003227298 R08: ffffffff911bc52f R09: 1ffffffff22378a5
R10: dffffc0000000000 R11: fffffbfff22378a6 R12: dffffc0000000000
R13: ffff88807ba38000 R14: ffffffff97553c88 R15: 1ffff92000644e40
 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline]
 debug_check_no_obj_freed+0x47b/0x520 lib/debugobjects.c:1020
 free_pages_prepare mm/page_alloc.c:1188 [inline]
 free_unref_page_prepare+0x1ed/0x8f0 mm/page_alloc.c:2366
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2459
 discard_slab mm/slub.c:2127 [inline]
 __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667
 put_cpu_partial+0x17c/0x250 mm/slub.c:2743
 __slab_free+0x319/0x400 mm/slub.c:3700
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:188 [inline]
 slab_post_alloc_hook+0x6a/0x4d0 mm/slab.h:767
 slab_alloc_node mm/slub.c:3495 [inline]
 __kmem_cache_alloc_node+0x194/0x250 mm/slub.c:3534
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 sctp_transport_new+0x7e/0x630 net/sctp/transport.c:97
 sctp_assoc_add_peer+0x24e/0x1350 net/sctp/associola.c:617
 sctp_connect_new_asoc+0x323/0x6a0 net/sctp/socket.c:1099
 sctp_sendmsg_new_asoc net/sctp/socket.c:1691 [inline]
 sctp_sendmsg+0x1519/0x27b0 net/sctp/socket.c:2011
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x61b/0x980 net/socket.c:2595
 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2649
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2687 [inline]
 __se_sys_sendmsg+0x1d0/0x2c0 net/socket.c:2685
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0683b9de59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f06849e8028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0683e25fa0 RCX: 00007f0683b9de59
RDX: 0000000000000010 RSI: 0000200000000780 RDI: 000000000000000a
RBP: 00007f0683c33e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0683e26038 R14: 00007f0683e25fa0 R15: 00007ffc7ba3cbf8
 </TASK>
net_ratelimit: 15136 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:6a:1a:dd:da:51:d5, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
net_ratelimit: 21381 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:6a:1a:dd:da:51:d5, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)