This patch adds integrity checking to two htree paths that are missing it.

 Currently, if a corrupted directory entry with rec_len=0 is encountered,
 we still trust that the data is valid. This can cause an infinite loop
 in htree_dirblock_to_tree() since the iteration loop will never make any
 progress.

 I initially had written a ext3_check_htree_entry(), but saw that
 ext3_dir_entry_2 is used for both htree and regular directory entries. Since
 ext3_check_dir_entry() is used for checking ext3_dir_entry_2, I used that.
 Can someone confirm that this is correct? There are other places where
 de->rec_len == 0 is used by itself and I'd be fine doing that too, but I
 figure more integrity checking isn't a bad thing.

 This fixes the problem described at:
 http://projects.info-pull.com/mokb/MOKB-10-11-2006.html

Signed-off-by: Jeff Mahoney <[EMAIL PROTECTED]>

diff -ruNpX ../dontdiff linux-2.6.18.orig/fs/ext3/namei.c 
linux-2.6.18.orig.devel/fs/ext3/namei.c
--- linux-2.6.18.orig/fs/ext3/namei.c   2006-11-09 00:06:37.000000000 -0500
+++ linux-2.6.18.orig.devel/fs/ext3/namei.c     2006-11-12 20:15:19.000000000 
-0500
@@ -551,6 +551,11 @@ static int htree_dirblock_to_tree(struct
                                           dir->i_sb->s_blocksize -
                                           EXT3_DIR_REC_LEN(0));
        for (; de < top; de = ext3_next_entry(de)) {
+               if (!ext3_check_dir_entry(__FUNCTION__, dir, de, bh,
+                                           (char *)de - bh->b_data)) {
+                       brelse(bh);
+                       return ERR_BAD_DX_DIR;
+               }
                ext3fs_dirhash(de->name, de->name_len, hinfo);
                if ((hinfo->hash < start_hash) ||
                    ((hinfo->hash == start_hash) &&
@@ -617,6 +622,11 @@ int ext3_htree_fill_tree(struct file *di
        if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
                de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
                de = ext3_next_entry(de);
+               if (!ext3_check_dir_entry(__FUNCTION__, dir, de, frames[0].bh,
+                                         (char *)de - frames[0].bh->b_data)) {
+                       err = ERR_BAD_DX_DIR;
+                       goto errout;
+               }
                if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0)
                        goto errout;
                count++;

-- 
Jeff Mahoney
-
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