Hello, syzbot found the following issue on: HEAD commit: feffde684ac2 Merge tag 'for-6.13-rc1-tag' of git://git.ker.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1420a330580000 kernel config: https://syzkaller.appspot.com/x/.config?x=50c7a61469ce77e7 dashboard link: https://syzkaller.appspot.com/bug?extid=1ec0f904ba50d06110b1 compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13c060f8580000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/3bb09093023b/disk-feffde68.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/9e37e48dc48a/vmlinux-feffde68.xz kernel image: https://storage.googleapis.com/syzbot-assets/36b46b3a6421/bzImage-feffde68.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+1ec0f904ba50d06110b1@xxxxxxxxxxxxxxxxxxxxxxxxx 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): P5930/1:b..l rcu: (detected by 0, t=10503 jiffies, g=6361, q=569 ncpus=2) task:syz-executor state:R running task stack:20208 pid:5930 tgid:5930 ppid:5919 flags:0x00000002 Call Trace: <TASK> context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:390 [inline] RIP: 0010:__rcu_read_lock+0x27/0xb0 kernel/rcu/tree_plugin.h:413 Code: 90 90 90 f3 0f 1e fa 55 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 4c 8b 3c 25 00 d6 03 00 49 81 c7 44 04 00 00 4c 89 fb <48> c1 eb 03 42 0f b6 04 33 84 c0 75 35 41 8b 2f ff c5 42 0f b6 04 RSP: 0018:ffffc900035f77e0 EFLAGS: 00000286 RAX: ffffffff81ae868a RBX: ffff888026cd5e44 RCX: ffff888026cd5a00 RDX: 0000000000000000 RSI: ffffffff8c5f63c0 RDI: 00007fc1f8581247 RBP: 0000000000000001 R08: ffffffff810a464d R09: ffffc900035f7990 R10: ffffc900035f78f0 R11: ffffffff818b36f0 R12: ffff888026cd5a00 R13: ffffffff818b36f0 R14: dffffc0000000000 R15: ffff888026cd5e44 rcu_read_lock include/linux/rcupdate.h:847 [inline] is_bpf_text_address+0x1f/0x2a0 kernel/bpf/core.c:768 kernel_text_address+0xa7/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_page+0xdef/0x1130 mm/page_alloc.c:2657 __slab_free+0x31b/0x3d0 mm/slub.c:4509 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4160 getname_flags+0xb7/0x540 fs/namei.c:139 user_path_at+0x24/0x60 fs/namei.c:3069 ksys_umount fs/namespace.c:2033 [inline] __do_sys_umount fs/namespace.c:2041 [inline] __se_sys_umount fs/namespace.c:2039 [inline] __x64_sys_umount+0xf1/0x170 fs/namespace.c:2039 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc1f8581247 RSP: 002b:00007fc1f886ecc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc1f8581247 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fc1f886ed80 RBP: 00007fc1f886ed80 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fc1f886fe00 R13: 00007fc1f85f3824 R14: 000000000000f97b R15: 00007fc1f886fe40 </TASK> rcu: rcu_preempt kthread starved for 10527 jiffies! g6361 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 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:26264 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: <TASK> context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:unwind_get_return_address+0x56/0x90 arch/x86/kernel/unwind_orc.c:369 Code: 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 7b b2 be 00 48 8b 3b e8 c3 73 1e 00 85 c0 74 14 43 80 3c 37 00 <74> 08 48 89 df e8 60 b2 be 00 48 8b 03 eb 02 31 c0 5b 41 5e 41 5f RSP: 0018:ffffc900001e6d20 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc900001e6d88 RCX: ffffffff91790000 RDX: ffffffff91940701 RSI: ffffc900001e0000 RDI: ffffffff81fe1859 RBP: ffffc900001e6dd0 R08: ffffc900001e7120 R09: 0000000000000000 R10: ffffc900001e6d90 R11: fffff5200003cdb4 R12: ffff88801d2e8000 R13: ffffffff818b36f0 R14: dffffc0000000000 R15: 1ffff9200003cdb1 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc1f886ecdc CR3: 000000007d414000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <NMI> </NMI> <TASK> arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 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:4104 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4160 __skb_ext_alloc net/core/skbuff.c:6924 [inline] skb_ext_add+0x14d/0x910 net/core/skbuff.c:7027 nf_bridge_alloc include/net/netfilter/br_netfilter.h:12 [inline] br_nf_pre_routing_ipv6+0x131/0x770 net/bridge/br_netfilter_ipv6.c:172 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x14eb/0x4690 net/core/dev.c:5566 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6877 napi_poll net/core/dev.c:6946 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7068 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 run_ksoftirqd+0xca/0x130 kernel/softirq.c:943 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> net_ratelimit: 52114 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: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: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: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) net_ratelimit: 58692 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: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: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: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) --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup