From: ChenXiaoSong <chenxiaosong2@huawei.com>
Date: Tue, 29 Mar 2022 19:32:07 +0800
Subject: [PATCH] Revert "NFSv4: Handle the special Linux file open access
mode"
Git-commit: ab0fc21bc7105b54bafd85bd8b82742f9e68898a
Patch-mainline: v5.18
References: git-fixes
This reverts commit 44942b4e457beda00981f616402a1a791e8c616e.
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: Lyu Tao <tao.lyu@epfl.ch>
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Acked-by: NeilBrown <neilb@suse.com>
---
fs/nfs/inode.c | 1 -
fs/nfs/nfs4file.c | 2 +-
2 files changed, 1 insertion(+), 2 deletions(-)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1002,7 +1002,6 @@ int nfs_open(struct inode *inode, struct
nfs_fscache_open_file(inode, filp);
return 0;
}
-EXPORT_SYMBOL_GPL(nfs_open);
/*
* This function is called whenever some part of NFS notices that
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -49,7 +49,7 @@ nfs4_file_open(struct inode *inode, stru
return err;
if ((openflags & O_ACCMODE) == 3)
- return nfs_open(inode, filp);
+ openflags--;
/* We can't create new files here */
openflags &= ~(O_CREAT|O_EXCL);