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BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xd62/0xe70 net/ipv4/ip_gre.c:661
 __netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 netdev_start_xmit include/linux/netdevice.h:4833 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 __dev_queue_xmit+0x1dec/0x31f0 net/core/dev.c:4256
 dev_queue_xmit+0x2b/0x30 include/linux/netdevice.h:3008
 packet_snd net/packet/af_packet.c:3073 [inline]
 packet_sendmsg+0x605b/0x78e0 net/packet/af_packet.c:3104
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg+0x258/0x440 net/socket.c:2565
 __compat_sys_sendmsg net/compat.c:343 [inline]
 __do_compat_sys_sendmsg net/compat.c:350 [inline]
 __se_compat_sys_sendmsg net/compat.c:347 [inline]
 __ia32_compat_sys_sendmsg+0x99/0xe0 net/compat.c:347
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:362 [inline]
 pskb_expand_head+0x24a/0x1a80 net/core/skbuff.c:1729
 __skb_cow include/linux/skbuff.h:3529 [inline]
 skb_cow_head include/linux/skbuff.h:3563 [inline]
 ipgre_xmit+0x750/0xe70 net/ipv4/ip_gre.c:637
 __netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 netdev_start_xmit include/linux/netdevice.h:4833 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 __dev_queue_xmit+0x1dec/0x31f0 net/core/dev.c:4256
 dev_queue_xmit+0x2b/0x30 include/linux/netdevice.h:3008
 packet_snd net/packet/af_packet.c:3073 [inline]
 packet_sendmsg+0x605b/0x78e0 net/packet/af_packet.c:3104
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg+0x258/0x440 net/socket.c:2565
 __compat_sys_sendmsg net/compat.c:343 [inline]
 __do_compat_sys_sendmsg net/compat.c:350 [inline]
 __se_compat_sys_sendmsg net/compat.c:347 [inline]
 __ia32_compat_sys_sendmsg+0x99/0xe0 net/compat.c:347
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 1 PID: 7651 Comm: syz-executor.2 Not tainted 6.0.0-rc5-syzkaller-48539-g523d2ce66d07 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
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