syzbot

=====================================================
BUG: KMSAN: uninit-value in packet_rcv+0x86d/0x2160 net/packet/af_packet.c:2086
CPU: 1 PID: 5236 Comm: systemd-udevd Not tainted 5.7.0-rc4-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+0x1c9/0x220 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
 packet_rcv+0x86d/0x2160 net/packet/af_packet.c:2086
 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 br_dev_queue_push_xmit+0x7f5/0x8b0 net/bridge/br_forward.c:52
 NF_HOOK include/linux/netfilter.h:307 [inline]
 br_forward_finish net/bridge/br_forward.c:65 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 __br_forward+0xa33/0xe30 net/bridge/br_forward.c:109
 deliver_clone net/bridge/br_forward.c:125 [inline]
 maybe_deliver net/bridge/br_forward.c:181 [inline]
 br_flood+0xb0b/0xf90 net/bridge/br_forward.c:223
 br_dev_xmit+0x1693/0x1730 net/bridge/br_device.c:93
 __netdev_start_xmit include/linux/netdevice.h:4533 [inline]
 netdev_start_xmit include/linux/netdevice.h:4547 [inline]
 xmit_one net/core/dev.c:3477 [inline]
 dev_hard_start_xmit+0x531/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x2056/0x2640 net/ipv6/ip6_output.c:117
 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143
 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176
 dst_output include/net/dst.h:435 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ndisc_send_skb+0x1047/0x15a0 net/ipv6/ndisc.c:506
 ndisc_send_rs+0xbd8/0xc30 net/ipv6/ndisc.c:700
 addrconf_rs_timer+0x62f/0xcf0 net/ipv6/addrconf.c:3889
 call_timer_fn+0x218/0x510 kernel/time/timer.c:1405
 expire_timers kernel/time/timer.c:1450 [inline]
 __run_timers+0xcff/0x1210 kernel/time/timer.c:1774
 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1787
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:375 [inline]
 irq_exit+0x230/0x280 kernel/softirq.c:416
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:546
 smp_apic_timer_interrupt+0x48/0x70 arch/x86/kernel/apic/apic.c:1143
 apic_timer_interrupt+0x2e/0x40 arch/x86/entry/entry_64.S:834
 </IRQ>
RIP: 0010:__msan_chain_origin+0x70/0x90 mm/kmsan/kmsan_instr.c:168
Code: 7d 35 44 89 f7 e8 d0 f4 ff ff be ff ff ff ff 65 0f c1 35 23 db 75 6f ff ce 75 1e 89 c3 e8 f8 05 31 ff 4c 89 7d e0 ff 75 e0 9d <89> d8 48 83 c4 10 5b 41 5e 41 5f 5d c3 0f 0b 48 c7 c7 31 3a e9 9d
RSP: 0018:ffffb52400d839c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000015da00c0 RBX: 0000000015da00c0 RCX: 0000000005d000c0
RDX: 0000000000000a20 RSI: 0000000000000000 RDI: 0000000005da00c0
RBP: ffffb52400d839f0 R08: 0000000000000003 R09: ffffb52400d8377c
R10: 0000000000000003 R11: ffffffff9d40083d R12: ffffb52400d4b040
R13: 0000000000000000 R14: 0000000005d000c0 R15: 0000000000000246
 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:599 [inline]
 seccomp_run_filters kernel/seccomp.c:272 [inline]
 __seccomp_filter+0x59e/0x26f0 kernel/seccomp.c:817
 __secure_computing+0x1fa/0x380 kernel/seccomp.c:950
 syscall_trace_enter+0x6eb/0xf60 arch/x86/entry/common.c:119
 do_syscall_64+0x57/0x160 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fd2cb92e2e2
Code: 48 8b 05 b9 db 2b 00 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 83 ff 01 77 33 48 63 fe b8 05 00 00 00 48 89 d6 0f 05 <48> 3d 00 f0 ff ff 77 06 f3 c3 0f 1f 40 00 48 8b 15 81 db 2b 00 f7
RSP: 002b:00007fff7ff2e268 EFLAGS: 00000246 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 000000000000000f RCX: 00007fd2cb92e2e2
RDX: 00007fff7ff2e270 RSI: 00007fff7ff2e270 RDI: 000000000000000f
RBP: 00007fd2ccabb710 R08: 000055f1b926c060 R09: 0000000000001010
R10: 00007fd2cbbecb58 R11: 0000000000000246 R12: 0000000000000000
R13: 000055f1b926ebc0 R14: 00000000000000ff R15: 000055f1b926ebc0

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:545 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:599 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:721 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2160 net/packet/af_packet.c:2085
 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 br_dev_queue_push_xmit+0x7f5/0x8b0 net/bridge/br_forward.c:52
 NF_HOOK include/linux/netfilter.h:307 [inline]
 br_forward_finish net/bridge/br_forward.c:65 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 __br_forward+0xa33/0xe30 net/bridge/br_forward.c:109
 deliver_clone net/bridge/br_forward.c:125 [inline]
 maybe_deliver net/bridge/br_forward.c:181 [inline]
 br_flood+0xb0b/0xf90 net/bridge/br_forward.c:223
 br_dev_xmit+0x1693/0x1730 net/bridge/br_device.c:93
 __netdev_start_xmit include/linux/netdevice.h:4533 [inline]
 netdev_start_xmit include/linux/netdevice.h:4547 [inline]
 xmit_one net/core/dev.c:3477 [inline]
 dev_hard_start_xmit+0x531/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x2056/0x2640 net/ipv6/ip6_output.c:117
 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143
 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176
 dst_output include/net/dst.h:435 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ndisc_send_skb+0x1047/0x15a0 net/ipv6/ndisc.c:506
 ndisc_send_rs+0xbd8/0xc30 net/ipv6/ndisc.c:700
 addrconf_rs_timer+0x62f/0xcf0 net/ipv6/addrconf.c:3889
 call_timer_fn+0x218/0x510 kernel/time/timer.c:1405
 expire_timers kernel/time/timer.c:1450 [inline]
 __run_timers+0xcff/0x1210 kernel/time/timer.c:1774
 run_timer_softirq+0x2d/0x50 kernel/time/timer.c:1787
 __do_softirq+0x311/0x83d kernel/softirq.c:293

Local variable ----regs@__bpf_prog_run32 created at:
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
=====================================================