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BUG: KMSAN: uninit-value in ip6_parse_tlv+0x703/0xfa0 net/ipv6/exthdrs.c:163
CPU: 0 PID: 12049 Comm: syz-executor.0 Not tainted 5.9.0-rc8-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:122
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:201
 ip6_parse_tlv+0x703/0xfa0 net/ipv6/exthdrs.c:163
 ipv6_parse_hopopts+0x540/0x860 net/ipv6/exthdrs.c:1043
 ip6_rcv_core+0x1e9a/0x2390 net/ipv6/ip6_input.c:278
 ipv6_rcv+0xdf/0x430 net/ipv6/ip6_input.c:304
 __netif_receive_skb_one_core net/core/dev.c:5286 [inline]
 __netif_receive_skb+0x1ec/0x640 net/core/dev.c:5400
 process_backlog+0x523/0xc10 net/core/dev.c:6242
 napi_poll+0x4aa/0x1090 net/core/dev.c:6688
 net_rx_action+0x35c/0xd40 net/core/dev.c:6758
 __do_softirq+0x1b9/0x7ed kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x6e/0x90 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:343 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:195
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 ip6_finish_output2+0x2457/0x2a40 net/ipv6/ip6_output.c:118
 __ip6_finish_output+0x9b8/0xa90 net/ipv6/ip6_output.c:143
 ip6_finish_output+0x143/0x4a0 net/ipv6/ip6_output.c:153
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip6_output+0x4a4/0x7e0 net/ipv6/ip6_output.c:176
 dst_output include/net/dst.h:443 [inline]
 ip6_local_out+0x17b/0x1e0 net/ipv6/output_core.c:179
 ip6_send_skb net/ipv6/ip6_output.c:1867 [inline]
 ip6_push_pending_frames+0x242/0x570 net/ipv6/ip6_output.c:1887
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x4183/0x4750 net/ipv6/raw.c:956
 inet_sendmsg+0x15b/0x1d0 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmmsg+0x835/0x1010 net/socket.c:2490
 __compat_sys_sendmmsg net/compat.c:361 [inline]
 __do_compat_sys_sendmmsg net/compat.c:368 [inline]
 __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:365
 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:365
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fda549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55d40cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200009c0
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:129 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:112
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2903 [inline]
 __kmalloc_node_track_caller+0x7de/0x1320 mm/slub.c:4507
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x309/0xae0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1094 [inline]
 __ip6_append_data+0x5247/0x72a0 net/ipv6/ip6_output.c:1590
 ip6_append_data+0x44b/0x6e0 net/ipv6/ip6_output.c:1759
 rawv6_sendmsg+0x31a9/0x4750 net/ipv6/raw.c:949
 inet_sendmsg+0x15b/0x1d0 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmmsg+0x835/0x1010 net/socket.c:2490
 __compat_sys_sendmmsg net/compat.c:361 [inline]
 __do_compat_sys_sendmmsg net/compat.c:368 [inline]
 __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:365
 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:365
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
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