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BUG: KMSAN: uninit-value in ip6_parse_tlv+0xa37/0xf80 net/ipv6/exthdrs.c:156
CPU: 0 PID: 10673 Comm: syz-executor.3 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
 ip6_parse_tlv+0xa37/0xf80 net/ipv6/exthdrs.c:156
 ipv6_destopt_rcv+0x630/0xe80 net/ipv6/exthdrs.c:308
 ip6_protocol_deliver_rcu+0x14a2/0x2660 net/ipv6/ip6_input.c:433
 ip6_input_finish net/ipv6/ip6_input.c:474 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip6_input+0x2dd/0x370 net/ipv6/ip6_input.c:483
 dst_input include/net/dst.h:449 [inline]
 ip6_rcv_finish+0x5fc/0x7f0 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ipv6_rcv+0x3bb/0x460 net/ipv6/ip6_input.c:307
 __netif_receive_skb_one_core net/core/dev.c:5281 [inline]
 __netif_receive_skb+0x265/0x670 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
 do_softirq kernel/softirq.c:338 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 ip6_finish_output2+0x24b4/0x2a70 net/ipv6/ip6_output.c:118
 __ip6_finish_output+0x9c0/0xa90 net/ipv6/ip6_output.c:143
 ip6_finish_output+0x14b/0x4b0 net/ipv6/ip6_output.c:153
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x68d/0x7f0 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:1865 [inline]
 ip6_push_pending_frames+0x252/0x5b0 net/ipv6/ip6_output.c:1885
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x42fe/0x4740 net/ipv6/raw.c:956
 inet_sendmsg+0x15b/0x1d0 net/ipv4/af_inet.c:814
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmmsg+0x808/0xf70 net/socket.c:2489
 __compat_sys_sendmmsg net/compat.c:480 [inline]
 __do_compat_sys_sendmmsg net/compat.c:487 [inline]
 __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:484
 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:484
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f88549
Code: Bad RIP value.
RSP: 002b:00000000f55400cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020007e40
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: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:2839 [inline]
 __kmalloc_node_track_caller+0xeab/0x12e0 mm/slub.c:4478
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1083 [inline]
 alloc_skb_with_frags+0x1f2/0xc10 net/core/skbuff.c:5770
 sock_alloc_send_pskb+0xc83/0xe50 net/core/sock.c:2356
 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2373
 __ip6_append_data+0x4fbf/0x71b0 net/ipv6/ip6_output.c:1581
 ip6_append_data+0x44b/0x6e0 net/ipv6/ip6_output.c:1757
 rawv6_sendmsg+0x2cfe/0x4740 net/ipv6/raw.c:949
 inet_sendmsg+0x15b/0x1d0 net/ipv4/af_inet.c:814
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmmsg+0x808/0xf70 net/socket.c:2489
 __compat_sys_sendmmsg net/compat.c:480 [inline]
 __do_compat_sys_sendmmsg net/compat.c:487 [inline]
 __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:484
 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:484
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2af/0x480 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
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