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BUG: KMSAN: uninit-value in update_stack_state+0x1ee/0xb40 arch/x86/kernel/unwind_frame.c:202
CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 update_stack_state+0x1ee/0xb40 arch/x86/kernel/unwind_frame.c:202
 unwind_next_frame+0x8c6/0xed0 arch/x86/kernel/unwind_frame.c:305
 arch_stack_walk+0x338/0x3d0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x117/0x1a0 kernel/stacktrace.c:123
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 kmsan_memcpy_memmove_metadata+0x272/0x2e0 mm/kmsan/kmsan.c:247
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:267
 __msan_memcpy+0x43/0x50 mm/kmsan/kmsan_instr.c:116
 skb_ext_maybe_cow net/core/skbuff.c:6118 [inline]
 skb_ext_add+0x477/0xbc0 net/core/skbuff.c:6180
 nf_bridge_unshare net/bridge/br_netfilter_hooks.c:160 [inline]
 br_nf_forward_ip+0x19a/0x2480 net/bridge/br_netfilter_hooks.c:589
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x17b/0x460 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:262 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 __br_forward+0x96e/0xec0 net/bridge/br_forward.c:109
 deliver_clone net/bridge/br_forward.c:125 [inline]
 br_flood+0xf26/0x1130 net/bridge/br_forward.c:232
 br_handle_frame_finish+0x1e35/0x2020 net/bridge/br_input.c:166
 br_nf_hook_thresh+0x576/0x700 net/bridge/br_netfilter_hooks.c:1021
 br_nf_pre_routing_finish_ipv6+0xf91/0x1110 net/bridge/br_netfilter_ipv6.c:187
 NF_HOOK include/linux/netfilter.h:307 [inline]
 br_nf_pre_routing_ipv6+0x7e2/0x8a0 net/bridge/br_netfilter_ipv6.c:236
 br_nf_pre_routing+0xfe7/0x25a0 net/bridge/br_netfilter_hooks.c:505
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:228 [inline]
 br_handle_frame+0xc83/0x25a0 net/bridge/br_input.c:356
 __netif_receive_skb_core+0x3710/0x6520 net/core/dev.c:5175
 __netif_receive_skb_one_core net/core/dev.c:5279 [inline]
 __netif_receive_skb+0x164/0x670 net/core/dev.c:5395
 process_backlog+0x50d/0xba0 net/core/dev.c:6239
 napi_poll+0x43b/0xfd0 net/core/dev.c:6684
 net_rx_action+0x35c/0xd40 net/core/dev.c:6752
 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:293
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:390 [inline]
 __irq_exit_rcu+0x226/0x270 kernel/softirq.c:420
 irq_exit_rcu+0xe/0x10 kernel/softirq.c:432
 sysvec_call_function_single+0x107/0x130 arch/x86/kernel/smp.c:243
 asm_sysvec_call_function_single+0x12/0x20 arch/x86/include/asm/idtentry.h:601
RIP: 0010:__nr_to_section include/linux/mmzone.h:1210 [inline]
RIP: 0010:pfn_valid include/linux/mmzone.h:1323 [inline]
RIP: 0010:kmsan_virt_addr_valid mm/kmsan/kmsan_shadow.c:91 [inline]
RIP: 0010:virt_to_page_or_null+0x46/0xf0 mm/kmsan/kmsan_shadow.c:129
Code: 00 48 01 fa 48 39 c2 77 55 8a 0d 72 45 77 10 48 89 d6 48 d3 ee 48 85 f6 75 44 48 89 d1 48 c1 e9 2e 75 3b 48 8b 0d 1a 4b c8 10 <48> 85 c9 74 2f 48 89 d6 48 c1 ee 22 4c 8b 0c f1 4d 85 c9 74 1f 48
RSP: 0018:ffff88812dfafd58 EFLAGS: 00000246
RAX: ffff8881adfb0024 RBX: ffff88812dfb0024 RCX: ffff88821fff0000
RDX: 000000012dfb0024 RSI: 0000000000000000 RDI: ffff88812dfb0024
RBP: ffff88812dfafd58 R08: ffffea000000000f R09: ffff88812fffa000
R10: 0000000000000004 R11: 0000000000000000 R12: ffff88812dfb0000
R13: 0000000000200000 R14: 0000000000000000 R15: 0000000000000001
 kmsan_get_metadata+0x116/0x180 mm/kmsan/kmsan_shadow.c:194
 kmsan_get_shadow_origin_ptr+0x6c/0xb0 mm/kmsan/kmsan_shadow.c:149
 __msan_metadata_ptr_for_load_4+0x10/0x20 mm/kmsan/kmsan_instr.c:54
 to_kthread kernel/kthread.c:83 [inline]
 kthread_should_stop+0x3a/0x130 kernel/kthread.c:111
 smpboot_thread_fn+0x76e/0xa90 kernel/smpboot.c:115
 kthread+0x551/0x590 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293

Local variable ----heads@__run_timers created at:
 __run_timers+0x61/0xd30 kernel/time/timer.c:1742
 __run_timers+0x61/0xd30 kernel/time/timer.c:1742
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