=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:121 [inline]
BUG: KMSAN: kernel-infoleak in copyout lib/iov_iter.c:156 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:623
 instrument_copy_to_user include/linux/instrumented.h:121 [inline]
 copyout lib/iov_iter.c:156 [inline]
 _copy_to_iter+0x69d/0x25c0 lib/iov_iter.c:623
 copy_to_iter include/linux/uio.h:153 [inline]
 simple_copy_to_iter+0xf3/0x140 net/core/datagram.c:519
 __skb_datagram_iter+0x2cb/0x1280 net/core/datagram.c:425
 skb_copy_datagram_iter+0xdc/0x210 net/core/datagram.c:533
 skb_copy_datagram_msg include/linux/skbuff.h:3620 [inline]
 netlink_recvmsg+0x660/0x1c60 net/netlink/af_netlink.c:1993
 ____sys_recvmsg+0x5b4/0xb40
 ___sys_recvmsg net/socket.c:2670 [inline]
 do_recvmmsg+0xee1/0x2120 net/socket.c:2764
 __sys_recvmmsg net/socket.c:2845 [inline]
 __do_sys_recvmmsg net/socket.c:2866 [inline]
 __se_sys_recvmmsg net/socket.c:2859 [inline]
 __x64_sys_recvmmsg+0x3c0/0x500 net/socket.c:2859
 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:3228 [inline]
 __kmalloc_node_track_caller+0xa3b/0x13c0 mm/slub.c:4963
 kmalloc_reserve net/core/skbuff.c:356 [inline]
 __alloc_skb+0x4db/0xe40 net/core/skbuff.c:427
 alloc_skb include/linux/skbuff.h:1116 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 ip6addrlbl_get+0xa08/0x1810 net/ipv6/addrlabel.c:608
 rtnetlink_rcv_msg+0x1275/0x18b0 net/core/rtnetlink.c:5563
 netlink_rcv_skb+0x447/0x800 net/netlink/af_netlink.c:2510
 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5590
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x107b/0x1350 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1717/0x18a0 net/netlink/af_netlink.c:1935
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 kernel_sendmsg+0x22c/0x2f0 net/socket.c:744
 sock_no_sendpage+0x218/0x2b0 net/core/sock.c:2998
 kernel_sendpage+0x4a0/0x5a0 net/socket.c:3504
 sock_sendpage+0x161/0x1a0 net/socket.c:1003
 pipe_to_sendpage+0x3f1/0x510 fs/splice.c:364
 splice_from_pipe_feed fs/splice.c:418 [inline]
 __splice_from_pipe+0x5df/0x1020 fs/splice.c:562
 splice_from_pipe fs/splice.c:597 [inline]
 generic_splice_sendpage+0x1d5/0x2c0 fs/splice.c:746
 do_splice_from fs/splice.c:767 [inline]
 do_splice+0x2481/0x2cd0 fs/splice.c:1079
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x946/0xb70 fs/splice.c:1332
 __x64_sys_splice+0x19d/0x200 fs/splice.c:1332
 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

Byte 17 of 26 is uninitialized
Memory access of size 26 starts at ffff8881532a0400
Data copied to user address 0000000020000000
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