ext4: validate directory entry data before use
authorDuane Griffin <duaneg@dghda.com>
Fri, 11 Jul 2008 23:27:31 +0000 (19:27 -0400)
committerTheodore Ts'o <tytso@mit.edu>
Fri, 11 Jul 2008 23:27:31 +0000 (19:27 -0400)
commitf3b35f063e9a795495fe2f7a2fe55fab11f8ab12
tree6007687f02066794f3d218f710df717f1b72076c
parent71dc8fbcf5f6363342bd636a646eeac7cfef25c3
ext4: validate directory entry data before use

ext4_dx_find_entry uses ext4_next_entry without verifying that the entry is
valid. If its rec_len == 0 this causes an infinite loop. Refactor the loop
to check the validity of entries before checking whether they match and
moving onto the next one.

There are other uses of ext4_next_entry in this file which also look
problematic. They should be reviewed and fixed if/when we have a test-case
that triggers them.

This patch fixes the first case (image hdb.25.softlockup.gz) reported in
http://bugzilla.kernel.org/show_bug.cgi?id=10882.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fs/ext4/namei.c