=====================================================
BUG: KMSAN: uninit-value in pskb_may_pull_reason include/linux/skbuff.h:2667 [inline]
BUG: KMSAN: uninit-value in pskb_may_pull include/linux/skbuff.h:2681 [inline]
BUG: KMSAN: uninit-value in llc_fixup_skb net/llc/llc_input.c:134 [inline]
BUG: KMSAN: uninit-value in llc_rcv+0x1107/0x14a0 net/llc/llc_input.c:177
 pskb_may_pull_reason include/linux/skbuff.h:2667 [inline]
 pskb_may_pull include/linux/skbuff.h:2681 [inline]
 llc_fixup_skb net/llc/llc_input.c:134 [inline]
 llc_rcv+0x1107/0x14a0 net/llc/llc_input.c:177
 __netif_receive_skb_list_ptype net/core/dev.c:5571 [inline]
 __netif_receive_skb_list_core+0x1028/0x1190 net/core/dev.c:5614
 __netif_receive_skb_list net/core/dev.c:5666 [inline]
 netif_receive_skb_list_internal+0xf06/0x14e0 net/core/dev.c:5757
 gro_normal_list include/net/gro.h:439 [inline]
 napi_complete_done+0x428/0x9f0 net/core/dev.c:6097
 gro_cell_poll+0x2d4/0x320 net/core/gro_cells.c:65
 __napi_poll+0xe4/0x950 net/core/dev.c:6527
 napi_poll net/core/dev.c:6594 [inline]
 net_rx_action+0x884/0x16d0 net/core/dev.c:6727
 __do_softirq+0x1b7/0x78f kernel/softirq.c:553
 do_softirq+0x9a/0xf0 kernel/softirq.c:454
 __local_bh_enable_ip+0x99/0xa0 kernel/softirq.c:381
 local_bh_enable+0x28/0x30 include/linux/bottom_half.h:33
 tun_rx_batched+0x840/0x920
 tun_get_user+0x564c/0x6940 drivers/net/tun.c:2002
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:1985 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x8ef/0x15c0 fs/read_write.c:584
 ksys_write+0x20f/0x4c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4449
 alloc_pages+0xd01/0x1040
 skb_page_frag_refill+0x2bf/0x7c0 net/core/sock.c:2920
 tun_build_skb drivers/net/tun.c:1679 [inline]
 tun_get_user+0xdf5/0x6940 drivers/net/tun.c:1819
 tun_chr_write_iter+0x3af/0x5d0 drivers/net/tun.c:2048
 call_write_iter include/linux/fs.h:1985 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x8ef/0x15c0 fs/read_write.c:584
 ksys_write+0x20f/0x4c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 9292 Comm: syz-executor.0 Not tainted 6.6.0-rc1-syzkaller-00125-ge42bebf6db29 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
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