This is a note to let you know that I've just added the patch titled
NFSv4: nfs_atomic_open() can race when looking up a non-regular file
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsv4-nfs_atomic_open-can-race-when-looking-up-a-non.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4c268333a5a4b48af0392b9f8cd70d08af1a942a
Author: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Date: Thu Jan 6 18:24:03 2022 -0500
NFSv4: nfs_atomic_open() can race when looking up a non-regular file
[ Upstream commit 1751fc1db36f6f411709e143d5393f92d12137a9 ]
If the file type changes back to being a regular file on the server
between the failed OPEN and our LOOKUP, then we need to re-run the OPEN.
Fixes: 0dd2b474d0b6 ("nfs: implement i_op->atomic_open()")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 0fb7189347af9..c3ae37036b9d1 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1612,12 +1612,17 @@ int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
if ((lookup_flags & LOOKUP_DIRECTORY) && inode &&
!S_ISDIR(inode->i_mode))
res = ERR_PTR(-ENOTDIR);
+ else if (inode && S_ISREG(inode->i_mode))
+ res = ERR_PTR(-EOPENSTALE);
} else if (!IS_ERR(res)) {
inode = d_inode(res);
if ((lookup_flags & LOOKUP_DIRECTORY) && inode &&
!S_ISDIR(inode->i_mode)) {
dput(res);
res = ERR_PTR(-ENOTDIR);
+ } else if (inode && S_ISREG(inode->i_mode)) {
+ dput(res);
+ res = ERR_PTR(-EOPENSTALE);
}
}
if (switched) {
