=====================================================
BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline]
BUG: KMSAN: uninit-value in iptable_mangle_hook+0x75a/0x8c0 net/ipv4/netfilter/iptable_mangle.c:81
CPU: 0 PID: 26361 Comm: syz-executor.1 Not tainted 5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x24c/0x2e0 lib/dump_stack.c:120
 kmsan_report+0xfb/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x5c/0xa0 mm/kmsan/kmsan_instr.c:197
 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:61 [inline]
 iptable_mangle_hook+0x75a/0x8c0 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:589
 nf_hook include/linux/netfilter.h:256 [inline]
 __ip_local_out+0x78c/0x840 net/ipv4/ip_output.c:115
 ip_local_out+0xa1/0x1e0 net/ipv4/ip_output.c:124
 iptunnel_xmit+0x931/0xf20 net/ipv4/ip_tunnel_core.c:82
 udp_tunnel_xmit_skb+0x526/0x640 net/ipv4/udp_tunnel_core.c:174
 geneve_xmit_skb drivers/net/geneve.c:959 [inline]
 geneve_xmit+0x2139/0x3c40 drivers/net/geneve.c:1059
 __netdev_start_xmit include/linux/netdevice.h:4825 [inline]
 netdev_start_xmit include/linux/netdevice.h:4839 [inline]
 xmit_one+0x2b6/0x760 net/core/dev.c:3605
 dev_hard_start_xmit net/core/dev.c:3621 [inline]
 __dev_queue_xmit+0x3432/0x4600 net/core/dev.c:4194
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4227
 packet_snd net/packet/af_packet.c:3006 [inline]
 packet_sendmsg+0x86ee/0x99d0 net/packet/af_packet.c:3031