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BUG: KMSAN: uninit-value in __gre_xmit net/ipv4/ip_gre.c:469 [inline]
BUG: KMSAN: uninit-value in ipgre_xmit+0xdc2/0xe20 net/ipv4/ip_gre.c:662
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xdc2/0xe20 net/ipv4/ip_gre.c:662
 __netdev_start_xmit include/linux/netdevice.h:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3573 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3589
 __dev_queue_xmit+0x34bb/0x52b0 net/core/dev.c:4369
 dev_queue_xmit include/linux/netdevice.h:3082 [inline]
 packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276
 packet_snd net/packet/af_packet.c:3087 [inline]
 packet_sendmsg+0x8b1d/0x9f30 net/packet/af_packet.c:3119
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x781/0xa30 net/socket.c:2194
 __do_sys_sendto net/socket.c:2206 [inline]
 __se_sys_sendto net/socket.c:2202 [inline]
 __ia32_sys_sendto+0x11f/0x1c0 net/socket.c:2202
 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+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:559
 pskb_expand_head+0x226/0x1a00 net/core/skbuff.c:2093
 __skb_cow include/linux/skbuff.h:3586 [inline]
 skb_cow_head include/linux/skbuff.h:3620 [inline]
 ipgre_xmit+0x74a/0xe20 net/ipv4/ip_gre.c:638
 __netdev_start_xmit include/linux/netdevice.h:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3573 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3589
 __dev_queue_xmit+0x34bb/0x52b0 net/core/dev.c:4369
 dev_queue_xmit include/linux/netdevice.h:3082 [inline]
 packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276
 packet_snd net/packet/af_packet.c:3087 [inline]
 packet_sendmsg+0x8b1d/0x9f30 net/packet/af_packet.c:3119
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 __sys_sendto+0x781/0xa30 net/socket.c:2194
 __do_sys_sendto net/socket.c:2206 [inline]
 __se_sys_sendto net/socket.c:2202 [inline]
 __ia32_sys_sendto+0x11f/0x1c0 net/socket.c:2202
 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+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 0 PID: 6205 Comm: syz-executor.5 Not tainted 6.6.0-rc7-syzkaller-00123-g3a568e3a961b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
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