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BUG: KMSAN: uninit-value in nf_flow_skb_encap_protocol net/netfilter/nf_flow_table_ip.c:290 [inline]
BUG: KMSAN: uninit-value in nf_flow_offload_lookup net/netfilter/nf_flow_table_ip.c:352 [inline]
BUG: KMSAN: uninit-value in nf_flow_offload_ip_hook+0x79a/0x3e40 net/netfilter/nf_flow_table_ip.c:424
 nf_flow_skb_encap_protocol net/netfilter/nf_flow_table_ip.c:290 [inline]
 nf_flow_offload_lookup net/netfilter/nf_flow_table_ip.c:352 [inline]
 nf_flow_offload_ip_hook+0x79a/0x3e40 net/netfilter/nf_flow_table_ip.c:424
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xf2/0x3f0 net/netfilter/core.c:626
 nf_hook_ingress include/linux/netfilter_netdev.h:34 [inline]
 nf_ingress net/core/dev.c:5318 [inline]
 __netif_receive_skb_core+0x430b/0x6190 net/core/dev.c:5406
 __netif_receive_skb_one_core net/core/dev.c:5536 [inline]
 __netif_receive_skb+0xca/0xa00 net/core/dev.c:5652
 netif_receive_skb_internal net/core/dev.c:5738 [inline]
 netif_receive_skb+0x58/0x660 net/core/dev.c:5798
 tun_rx_batched+0x3ee/0x980 drivers/net/tun.c:1549
 tun_get_user+0x5566/0x69e0 drivers/net/tun.c:2002
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:2108 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xb63/0x1520 fs/read_write.c:590
 ksys_write+0x20f/0x4c0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:652
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xba/0x120 arch/x86/entry/common.c:321
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x7f/0x89

Uninit was created at:
 __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
 alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
 alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
 skb_page_frag_refill+0x2bf/0x7c0 net/core/sock.c:2921
 tun_build_skb drivers/net/tun.c:1679 [inline]
 tun_get_user+0x1258/0x69e0 drivers/net/tun.c:1819
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:2108 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xb63/0x1520 fs/read_write.c:590
 ksys_write+0x20f/0x4c0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:652
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xba/0x120 arch/x86/entry/common.c:321
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x7f/0x89

CPU: 1 PID: 6528 Comm: syz-executor.0 Not tainted 6.9.0-rc2-syzkaller-00042-g3e92c1e6cd87 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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