tree d2f67c0b1b7a3fd7b601fd85ca7f21f607fdb55b
parent aa9660196b250b850c9d06046c9f3b1eb965a708
author Carlos Maiolino <cmaiolino@redhat.com> 1349233163 -0300
committer Jan Kara <jack@suse.cz> 1349817702 +0200

ext3: ext3_bread usage audit

This is the ext3 version of the same patch applied to Ext4, where such goal is
to audit the usage of ext3_bread() due a possible misinterpretion of its return
value.

Focused on directory blocks, a NULL value returned from ext3_bread() means a
hole, which cannot exist into a directory inode. It can pass undetected after a
fix in an uninitialized error variable.

The (now) initialized variable into ext3_getblk() may lead to a zero'ed return
value of ext3_bread() to its callers, which can make the caller do not detect
the hole in the directory inode.

This patch creates a new wrapper function ext3_dir_bread() which checks for
holes properly, reports error, and returns EIO in that case.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>