fs: Teach path_connected to handle nfs filesystems with multiple roots.

[platform/kernel/linux-rpi.git] / fs / namei.c

diff --git a/fs/namei.c b/fs/namei.c
index cbe24e3..f839b07 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -578,9 +578,10 @@ static int __nd_alloc_stack(struct nameidata *nd)
 static bool path_connected(const struct path *path)
 {
        struct vfsmount *mnt = path->mnt;
+       struct super_block *sb = mnt->mnt_sb;
 
-       /* Only bind mounts can have disconnected paths */
-       if (mnt->mnt_root == mnt->mnt_sb->s_root)
+       /* Bind mounts and multi-root filesystems can have disconnected paths */
+       if (!(sb->s_iflags & SB_I_MULTIROOT) && (mnt->mnt_root == sb->s_root))
                return true;
 
        return is_subdir(path->dentry, mnt->mnt_root);