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BUG: KMSAN: uninit-value in ip6_parse_tlv+0x8b8/0xcb0 net/ipv6/exthdrs.c:169
CPU: 0 PID: 8832 Comm: syz-fuzzer 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
 ip6_parse_tlv+0x8b8/0xcb0 net/ipv6/exthdrs.c:169
 ipv6_parse_hopopts+0x493/0x7c0 net/ipv6/exthdrs.c:1043
 ip6_rcv_core+0x1b08/0x1ff0 net/ipv6/ip6_input.c:278
 ipv6_rcv+0xe3/0x710 net/ipv6/ip6_input.c:304
 __netif_receive_skb_one_core net/core/dev.c:5188 [inline]
 __netif_receive_skb net/core/dev.c:5302 [inline]
 process_backlog+0xa41/0x1410 net/core/dev.c:6134
 napi_poll net/core/dev.c:6572 [inline]
 net_rx_action+0x786/0x1aa0 net/core/dev.c:6640
 __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: 0033:0x45e7a6
Code: 48 01 c9 48 8d 05 3a f6 6b 00 66 0f 38 00 0c c8 eb d0 66 0f 38 dc c0 66 0f d6 02 c3 f3 0f 6f 08 eb c0 66 0f ef 0d 4a bc 2b 01 <66> 0f 38 dc c9 f3 0f 6f 10 f3 0f 6f 5c 08 f0 66 0f ef d0 66 0f ef
RSP: 002b:000000c00066ab78 EFLAGS: 00000283 ORIG_RAX: ffffffffffffff13
RAX: 0000000000973bb1 RBX: 000000000045e6d0 RCX: 0000000000000011
RDX: 000000c00066ab90 RSI: 000000c00066ac00 RDI: 0000000000000001
RBP: 000000c00066abe0 R08: 000000000096251e R09: 000000000096251e
R10: 000000c00000cd80 R11: 000000000087bda0 R12: 00000000000000f1
R13: 0000000000000000 R14: 0000000000adc0ee R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2802 [inline]
 __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4436
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1083 [inline]
 __ip6_append_data+0x490c/0x63e0 net/ipv6/ip6_output.c:1588
 ip6_append_data+0x3cb/0x660 net/ipv6/ip6_output.c:1757
 rawv6_sendmsg+0x32bb/0x5c30 net/ipv6/raw.c:949
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0x1056/0x1350 net/socket.c:2362
 ___sys_sendmsg net/socket.c:2416 [inline]
 __sys_sendmsg+0x623/0x750 net/socket.c:2449
 __do_sys_sendmsg net/socket.c:2458 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2456
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2456
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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