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 4.9-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-regular-file.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 1751fc1db36f6f411709e143d5393f92d12137a9 Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Date: Thu, 6 Jan 2022 18:24:03 -0500
Subject: NFSv4: nfs_atomic_open() can race when looking up a non-regular file
From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
commit 1751fc1db36f6f411709e143d5393f92d12137a9 upstream.
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: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/nfs/dir.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1607,12 +1607,17 @@ no_open:
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) {
Patches currently in stable-queue which might be from trond.myklebust@xxxxxxxxxxxxxxx are
queue-4.9/nfsv4-handle-case-where-the-lookup-of-a-directory-fails.patch
queue-4.9/nfsv4-nfs_atomic_open-can-race-when-looking-up-a-non-regular-file.patch
