vfs: fix mkdirat to retry once on an ESTALE error

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index b70c191..1beebc1 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3243,8 +3243,10 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
        struct dentry *dentry;
        struct path path;
        int error;
+       unsigned int lookup_flags = LOOKUP_DIRECTORY;
 
-       dentry = user_path_create(dfd, pathname, &path, LOOKUP_DIRECTORY);
+retry:
+       dentry = user_path_create(dfd, pathname, &path, lookup_flags);
        if (IS_ERR(dentry))
                return PTR_ERR(dentry);
 
@@ -3254,6 +3256,10 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
        if (!error)
                error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
        done_path_create(&path, dentry);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
        return error;
 }