dcache: d_splice_alias should detect loops
I believe this can only happen in the case of a corrupted filesystem.
So -EIO looks like the appropriate error.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/dcache.c b/fs/dcache.c
index 85a2aad..ad13700 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2706,6 +2706,11 @@
dput(new);
return ERR_PTR(-EIO);
}
+ if (d_ancestor(new, dentry)) {
+ spin_unlock(&inode->i_lock);
+ dput(new);
+ return ERR_PTR(-EIO);
+ }
write_seqlock(&rename_lock);
__d_materialise_dentry(dentry, new);
write_sequnlock(&rename_lock);
