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BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x501/0x3dc0 net/ipv4/ip_tunnel.c:658
 ip_tunnel_xmit+0x501/0x3dc0 net/ipv4/ip_tunnel.c:658
 __gre_xmit net/ipv4/ip_gre.c:471 [inline]
 ipgre_xmit+0x127e/0x1310 net/ipv4/ip_gre.c:659
 __netdev_start_xmit include/linux/netdevice.h:4778 [inline]
 netdev_start_xmit include/linux/netdevice.h:4792 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3532
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3548
 __dev_queue_xmit+0x22ee/0x3500 net/core/dev.c:4176
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4209
 packet_snd net/packet/af_packet.c:3063 [inline]
 packet_sendmsg+0x6671/0x7d60 net/packet/af_packet.c:3094
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 __sys_sendto+0x9ef/0xc70 net/socket.c:2040
 __do_sys_sendto net/socket.c:2052 [inline]
 __se_sys_sendto net/socket.c:2048 [inline]
 __ia32_sys_sendto+0x1a4/0x220 net/socket.c:2048
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:754 [inline]
 slab_alloc_node mm/slub.c:3231 [inline]
 __kmalloc_node_track_caller+0xde3/0x14f0 mm/slub.c:4962
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 pskb_expand_head+0x26d/0x1fd0 net/core/skbuff.c:1700
 __skb_cow include/linux/skbuff.h:3476 [inline]
 skb_cow_head include/linux/skbuff.h:3510 [inline]
 ipgre_xmit+0xb01/0x1310 net/ipv4/ip_gre.c:636
 __netdev_start_xmit include/linux/netdevice.h:4778 [inline]
 netdev_start_xmit include/linux/netdevice.h:4792 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3532
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3548
 __dev_queue_xmit+0x22ee/0x3500 net/core/dev.c:4176
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4209
 packet_snd net/packet/af_packet.c:3063 [inline]
 packet_sendmsg+0x6671/0x7d60 net/packet/af_packet.c:3094
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 __sys_sendto+0x9ef/0xc70 net/socket.c:2040
 __do_sys_sendto net/socket.c:2052 [inline]
 __se_sys_sendto net/socket.c:2048 [inline]
 __ia32_sys_sendto+0x1a4/0x220 net/socket.c:2048
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 1 PID: 11860 Comm: syz-executor.4 Not tainted 5.18.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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