net: add sock_init_data_uid()

mainline inclusion
from mainline-v6.3-rc1
commit 584f3742
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6I7UC
CVE: CVE-2023-1076

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=584f3742890e966d2f0a1f3c418c9ead70b2d99e



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Add sock_init_data_uid() to explicitly initialize the socket uid.
To initialise the socket uid, sock_init_data() assumes a the struct
socket* sock is always embedded in a struct socket_alloc, used to
access the corresponding inode uid. This may not be true.
Examples are sockets created in tun_chr_open() and tap_open().

Fixes: 86741ec2 ("net: core: Add a UID field to struct sock.")
Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Conflicts:
	net/core/sock.c

Signed-off-by: Baisong Zhong <zhongbaisong@huawei.com>
Reviewed-by: Liu Jian <liujian56@huawei.com>
Reviewed-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com>