NFS: Be strict about dentry revalidation when doing exclusive create

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 14 insertions, 15 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 393c4813691..c2207e3f263 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -669,6 +669,19 @@ static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigne
 }
 
 /*
+ * Use intent information to check whether or not we're going to do
+ * an O_EXCL create using this path component.
+ */
+static int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
+{
+        if (NFS_PROTO(dir)->version == 2)
+                return 0;
+        if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_CREATE) == 0)
+                return 0;
+        return (nd->intent.open.flags & O_EXCL) != 0;
+}
+
+/*
  * Inode and filehandle revalidation for lookups.
  *
  * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
@@ -754,7 +767,7 @@ static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
         }
 
         /* Force a full look up iff the parent directory has changed */
-        if (nfs_check_verifier(dir, dentry)) {
+        if (!nfs_is_exclusive_create(dir, nd) && nfs_check_verifier(dir, dentry)) {
                 if (nfs_lookup_verify_inode(inode, nd))
                         goto out_zap_parent;
                 goto out_valid;
@@ -848,20 +861,6 @@ struct dentry_operations nfs_dentry_operations = {
         .d_iput         = nfs_dentry_iput,
 };
 
-/*
- * Use intent information to check whether or not we're going to do
- * an O_EXCL create using this path component.
- */
-static inline
-int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
-{
-        if (NFS_PROTO(dir)->version == 2)
-                return 0;
-        if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_CREATE) == 0)
-                return 0;
-        return (nd->intent.open.flags & O_EXCL) != 0;
-}
-
 static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
 {
         struct dentry *res;