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BUG: KMSAN: uninit-value in hsr_register_frame_in+0x374/0x380 net/hsr/hsr_framereg.c:439
 hsr_register_frame_in+0x374/0x380 net/hsr/hsr_framereg.c:439
 hsr_forward_skb+0xf0e/0x3470 net/hsr/hsr_forward.c:619
 hsr_handle_frame+0x9d6/0xac0 net/hsr/hsr_slave.c:69
 __netif_receive_skb_core+0x2171/0x5de0 net/core/dev.c:5359
 __netif_receive_skb_one_core net/core/dev.c:5463 [inline]
 __netif_receive_skb+0xf2/0x630 net/core/dev.c:5579
 netif_receive_skb_internal+0x1b3/0x3c0 net/core/dev.c:5665
 netif_receive_skb+0x49/0x360 net/core/dev.c:5724
 tun_rx_batched+0xadd/0xd50
 tun_get_user+0x56e3/0x5b20 drivers/net/tun.c:1912
 tun_chr_write_iter+0x407/0x580 drivers/net/tun.c:1942
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x1318/0x2030 fs/read_write.c:590
 ksys_write+0x28b/0x510 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0xdb/0x120 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was stored to memory at:
 hsr_fill_frame_info+0x74e/0x770 net/hsr/hsr_forward.c:536
 fill_frame_info net/hsr/hsr_forward.c:602 [inline]
 hsr_forward_skb+0x793/0x3470 net/hsr/hsr_forward.c:616
 hsr_handle_frame+0x9d6/0xac0 net/hsr/hsr_slave.c:69
 __netif_receive_skb_core+0x2171/0x5de0 net/core/dev.c:5359
 __netif_receive_skb_one_core net/core/dev.c:5463 [inline]
 __netif_receive_skb+0xf2/0x630 net/core/dev.c:5579
 netif_receive_skb_internal+0x1b3/0x3c0 net/core/dev.c:5665
 netif_receive_skb+0x49/0x360 net/core/dev.c:5724
 tun_rx_batched+0xadd/0xd50
 tun_get_user+0x56e3/0x5b20 drivers/net/tun.c:1912
 tun_chr_write_iter+0x407/0x580 drivers/net/tun.c:1942
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x1318/0x2030 fs/read_write.c:590
 ksys_write+0x28b/0x510 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0xdb/0x120 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Uninit was created at:
 __alloc_pages+0xbbf/0x1090 mm/page_alloc.c:5409
 alloc_pages+0x8a5/0xb80
 skb_page_frag_refill+0x34f/0x7a0 net/core/sock.c:2705
 tun_build_skb+0x248/0x1d60 drivers/net/tun.c:1589
 tun_get_user+0x10a9/0x5b20 drivers/net/tun.c:1728
 tun_chr_write_iter+0x407/0x580 drivers/net/tun.c:1942
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x1318/0x2030 fs/read_write.c:590
 ksys_write+0x28b/0x510 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0xdb/0x120 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 0 PID: 13403 Comm: syz-executor.0 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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