NFSv4.2 fix problems with __nfs42_ssc_open

stable inclusion
from stable-v5.10.140
commit 5e49ea099850feadcbf33c74b4f514a3e8049b91
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I63FTT

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5e49ea099850feadcbf33c74b4f514a3e8049b91



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[ Upstream commit fcfc8be1 ]

A destination server while doing a COPY shouldn't accept using the
passed in filehandle if its not a regular filehandle.

If alloc_file_pseudo() has failed, we need to decrement a reference
on the newly created inode, otherwise it leaks.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Fixes: ec4b0925 ("NFS: inter ssc open")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>