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@xxxxxxx> Signed-off-by: ChenXiaoSong <chenxiaosong2@xxxxxxxxxx> --- fs/nfs/inode.c | 1 - fs/nfs/nfs4file.c | 2 +- 2 files changed, 1 insertion(+), 2 deletions(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 3351c2de3e08..bb91b228f1e5 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -1180,7 +1180,6 @@ int nfs_open(struct inode *inode, struct file *filp) nfs_fscache_open_file(inode, filp); return 0; } -EXPORT_SYMBOL_GPL(nfs_open); /* * This function is called whenever some part of NFS notices that diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c index e79ae4cbc395..c178db86a6e8 100644 --- a/fs/nfs/nfs4file.c +++ b/fs/nfs/nfs4file.c @@ -51,7 +51,7 @@ nfs4_file_open(struct inode *inode, struct file *filp) 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); -- 2.31.1