udf: Properly detect stale inodes

NFS can easily ask for inodes that are already deleted. Currently UDF
happily returns such inodes which is a bug. Return -ESTALE if
udf_read_inode() is asked to read deleted inode.

Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 788fc58..3a44d91 100644 (file)
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1435,8 +1435,10 @@ reread:
        read_unlock(&sbi->s_cred_lock);
 
        link_count = le16_to_cpu(fe->fileLinkCount);
-       if (!link_count)
-               link_count = 1;
+       if (!link_count) {
+               ret = -ESTALE;
+               goto out;
+       }
        set_nlink(inode, link_count);
 
        inode->i_size = le64_to_cpu(fe->informationLength);