stable inclusion
from stable-v5.10.111
commit c688705a3978dd637389684bc5244927aeb8a67d
category: bugfix
bugzilla: 186205, https://gitee.com/openeuler/kernel/issues/I5BZTX
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c688705a3978dd637389684bc5244927aeb8a67d

--------------------------------

[ Upstream commit ab0fc21b ]

This reverts commit 44942b4e.

After secondly opening a file with O_ACCMODE|O_DIRECT flags,
nfs4_valid_open_stateid() will dereference NULL nfs4_state when lseek().

Reproducer:
  1. mount -t nfs -o vers=4.2 $server_ip:/ /mnt/
  2. fd = open("/mnt/file", O_ACCMODE|O_DIRECT|O_CREAT)
  3. close(fd)
  4. fd = open("/mnt/file", O_ACCMODE|O_DIRECT)
  5. lseek(fd)
Reported-by: NLyu Tao <tao.lyu@epfl.ch>
Signed-off-by: NChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChenXiaoSong <chenxiaosong2@huawei.com>
Reviewed-by: NZhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>