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BUG: KMSAN: uninit-value in fib_get_nhs+0x13a5/0x1f50 net/ipv4/fib_semantics.c:708
 fib_get_nhs+0x13a5/0x1f50 net/ipv4/fib_semantics.c:708
 fib_create_info+0x2444/0x48d0 net/ipv4/fib_semantics.c:1453
 fib_table_insert+0x3f3/0x3a40 net/ipv4/fib_trie.c:1224
 inet_rtm_newroute+0x297/0x480 net/ipv4/fib_frontend.c:886
 rtnetlink_rcv_msg+0x148d/0x18d0 net/core/rtnetlink.c:5571
 netlink_rcv_skb+0x40c/0x7e0 net/netlink/af_netlink.c:2496
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5589
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x1075/0x1340 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x14cf/0x1710 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 ____sys_sendmsg+0xe11/0x12c0 net/socket.c:2409
 ___sys_sendmsg net/socket.c:2463 [inline]
 __sys_sendmsg+0x704/0x840 net/socket.c:2492
 __do_sys_sendmsg net/socket.c:2501 [inline]
 __se_sys_sendmsg net/socket.c:2499 [inline]
 __x64_sys_sendmsg+0xe2/0x120 net/socket.c:2499
 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:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1126 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline]
 netlink_sendmsg+0xde3/0x1710 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 ____sys_sendmsg+0xe11/0x12c0 net/socket.c:2409
 ___sys_sendmsg net/socket.c:2463 [inline]
 __sys_sendmsg+0x704/0x840 net/socket.c:2492
 __do_sys_sendmsg net/socket.c:2501 [inline]
 __se_sys_sendmsg net/socket.c:2499 [inline]
 __x64_sys_sendmsg+0xe2/0x120 net/socket.c:2499
 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: 1 PID: 18022 Comm: syz-executor.3 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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