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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: 1 PID: 23941 Comm: syz-executor.2 Not tainted 5.9.0-rc4-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:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:201
 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:136 [inline]
 nf_hook_slow+0x17b/0x460 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:256 [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:82
 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel_core.c:190
 geneve_xmit_skb drivers/net/geneve.c:956 [inline]
 geneve_xmit+0x373e/0x3c00 drivers/net/geneve.c:1055
 __netdev_start_xmit include/linux/netdevice.h:4634 [inline]
 netdev_start_xmit include/linux/netdevice.h:4648 [inline]
 xmit_one+0x3cf/0x750 net/core/dev.c:3561
 dev_hard_start_xmit net/core/dev.c:3577 [inline]
 __dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4136
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4169
 packet_snd net/packet/af_packet.c:2989 [inline]
 packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3014
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 __sys_sendto+0x9dc/0xc80 net/socket.c:1992
 __do_sys_sendto net/socket.c:2004 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2000
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2000
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45dd99
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3612044c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000002d600 RCX: 000000000045dd99
RDX: 000000000000000e RSI: 0000000020000080 RDI: 0000000000000003
RBP: 000000000118bf78 R08: 0000000020000000 R09: 0000000000000080
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c
R13: 000000000169fb6f R14: 00007f36120459c0 R15: 000000000118bf2c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:311
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:151
 iptunnel_xmit+0xbb8/0xf00 net/ipv4/ip_tunnel_core.c:76
 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel_core.c:190
 geneve_xmit_skb drivers/net/geneve.c:956 [inline]
 geneve_xmit+0x373e/0x3c00 drivers/net/geneve.c:1055
 __netdev_start_xmit include/linux/netdevice.h:4634 [inline]
 netdev_start_xmit include/linux/netdevice.h:4648 [inline]
 xmit_one+0x3cf/0x750 net/core/dev.c:3561
 dev_hard_start_xmit net/core/dev.c:3577 [inline]
 __dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4136
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4169
 packet_snd net/packet/af_packet.c:2989 [inline]
 packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3014
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 __sys_sendto+0x9dc/0xc80 net/socket.c:1992
 __do_sys_sendto net/socket.c:2004 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2000
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2000
 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:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 __kmalloc_node_track_caller+0x9aa/0x12f0 mm/slub.c:4511
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1094 [inline]
 alloc_skb_with_frags+0x1f2/0xc10 net/core/skbuff.c:5771
 sock_alloc_send_pskb+0xc83/0xe50 net/core/sock.c:2348
 packet_alloc_skb net/packet/af_packet.c:2837 [inline]
 packet_snd net/packet/af_packet.c:2932 [inline]
 packet_sendmsg+0x6abb/0x9a80 net/packet/af_packet.c:3014
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 __sys_sendto+0x9dc/0xc80 net/socket.c:1992
 __do_sys_sendto net/socket.c:2004 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2000
 __x64_sys_sendto+0x6e/0x90 net/socket.c:2000
 do_syscall_64+0x9f/0x140 arch/x86/entry/common.c:48
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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