isofs: avoid info leak on export
commit fe685aabf7c8c9f138e5ea900954d295bf229175 upstream.
For type 1 the parent_offset member in struct isofs_fid gets copied
uninitialized to userland. Fix this by initializing it to 0.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/isofs/export.c b/fs/isofs/export.c
index 516eb21..fd88add 100644
--- a/fs/isofs/export.c
+++ b/fs/isofs/export.c
@@ -135,6 +135,7 @@
len = 3;
fh32[0] = ei->i_iget5_block;
fh16[2] = (__u16)ei->i_iget5_offset; /* fh16 [sic] */
+ fh16[3] = 0; /* avoid leaking uninitialized data */
fh32[2] = inode->i_generation;
if (connectable && !S_ISDIR(inode->i_mode)) {
struct inode *parent;