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BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline]
BUG: KMSAN: uninit-value in iptable_mangle_hook+0x75b/0x870 net/ipv4/netfilter/iptable_mangle.c:81
CPU: 0 PID: 12584 Comm: syz-executor.0 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __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
 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline]
 iptable_mangle_hook+0x75b/0x870 net/ipv4/netfilter/iptable_mangle.c:81
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x17b/0x460 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:262 [inline]
 __ip_local_out+0x71a/0x840 net/ipv4/ip_output.c:114
 ip_local_out+0xa1/0x1e0 net/ipv4/ip_output.c:123
 iptunnel_xmit+0x9b6/0xf00 net/ipv4/ip_tunnel_core.c:81
 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel.c:190
 geneve_xmit_skb drivers/net/geneve.c:929 [inline]
 geneve_xmit+0x180e/0x3200 drivers/net/geneve.c:1005
 __netdev_start_xmit include/linux/netdevice.h:4611 [inline]
 netdev_start_xmit include/linux/netdevice.h:4625 [inline]
 xmit_one+0x3cf/0x750 net/core/dev.c:3556
 dev_hard_start_xmit net/core/dev.c:3572 [inline]
 __dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x9f8/0xca0 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5b9
Code: Bad RIP value.
RSP: 002b:00007fde733c4c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000002d140 RCX: 000000000045d5b9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 000000000118cf98 R08: 00000000200001c0 R09: 0000000000000080
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 000000000169fb6f R14: 00007fde733c59c0 R15: 000000000118cf4c

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
 iptunnel_xmit+0xbb8/0xf00 net/ipv4/ip_tunnel_core.c:75
 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel.c:190
 geneve_xmit_skb drivers/net/geneve.c:929 [inline]
 geneve_xmit+0x180e/0x3200 drivers/net/geneve.c:1005
 __netdev_start_xmit include/linux/netdevice.h:4611 [inline]
 netdev_start_xmit include/linux/netdevice.h:4625 [inline]
 xmit_one+0x3cf/0x750 net/core/dev.c:3556
 dev_hard_start_xmit net/core/dev.c:3572 [inline]
 __dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x9f8/0xca0 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

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
 packet_alloc_skb net/packet/af_packet.c:2827 [inline]
 packet_snd net/packet/af_packet.c:2922 [inline]
 packet_sendmsg+0x6abb/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x9f8/0xca0 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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