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BUG: KMSAN: uninit-value in ip_rcv_core+0xf4c/0x1480 net/ipv4/ip_input.c:476
CPU: 0 PID: 8511 Comm: syz-executor835 Not tainted 5.10.0-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+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:197
 ip_rcv_core+0xf4c/0x1480 net/ipv4/ip_input.c:476
 ip_rcv+0xc7/0x820 net/ipv4/ip_input.c:535
 __netif_receive_skb_one_core net/core/dev.c:5315 [inline]
 __netif_receive_skb+0x1ec/0x640 net/core/dev.c:5429
 process_backlog+0x517/0xbd0 net/core/dev.c:6319
 napi_poll+0x40a/0x1020 net/core/dev.c:6763
 net_rx_action+0x34c/0xd30 net/core/dev.c:6833
 __do_softirq+0x1a9/0x6fa 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:730 [inline]
 __dev_queue_xmit+0x3b3e/0x4590 net/core/dev.c:4167
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173
 packet_snd net/packet/af_packet.c:2992 [inline]
 packet_sendmsg+0x8778/0x9a60 net/packet/af_packet.c:3017
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6f1/0x840 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x444009
Code: e8 6c 05 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 9b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffddbb41cd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000444009
RDX: 0000000000000000 RSI: 0000000020000580 RDI: 0000000000000003
RBP: 00007ffddbb41ce0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000002569a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:289
 __msan_chain_origin+0x57/0xa0 mm/kmsan/kmsan_instr.c:147
 iptunnel_xmit+0xbd6/0xf20 net/ipv4/ip_tunnel_core.c:76
 udp_tunnel_xmit_skb+0x526/0x640 net/ipv4/udp_tunnel_core.c:190
 geneve_xmit_skb drivers/net/geneve.c:959 [inline]
 geneve_xmit+0x209e/0x3c20 drivers/net/geneve.c:1059
 __netdev_start_xmit include/linux/netdevice.h:4718 [inline]
 netdev_start_xmit include/linux/netdevice.h:4732 [inline]
 xmit_one+0x2b6/0x760 net/core/dev.c:3564
 dev_hard_start_xmit net/core/dev.c:3580 [inline]
 __dev_queue_xmit+0x3426/0x4590 net/core/dev.c:4140
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4173
 packet_snd net/packet/af_packet.c:2992 [inline]
 packet_sendmsg+0x8778/0x9a60 net/packet/af_packet.c:3017
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6f1/0x840 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:121 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:104
 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:76
 slab_alloc_node mm/slub.c:2906 [inline]
 __kmalloc_node_track_caller+0xa48/0x1610 mm/slub.c:4512
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x318/0xb00 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1094 [inline]
 alloc_skb_with_frags+0x1f3/0xc10 net/core/skbuff.c:5832
 sock_alloc_send_pskb+0xcc4/0xe80 net/core/sock.c:2329
 packet_alloc_skb net/packet/af_packet.c:2840 [inline]
 packet_snd net/packet/af_packet.c:2935 [inline]
 packet_sendmsg+0x6aab/0x9a60 net/packet/af_packet.c:3017
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 ____sys_sendmsg+0xcfc/0x12f0 net/socket.c:2353
 ___sys_sendmsg net/socket.c:2407 [inline]
 __sys_sendmsg+0x6f1/0x840 net/socket.c:2440
 __do_sys_sendmsg net/socket.c:2449 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2447
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2447
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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