From: Roman Borisov <ext-roman.borisov@nokia.com>
Subject: ext3: ext4: Using uninitialized value
Date: Wed, 13 Oct 2010 18:40:22 +0400
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Cc: Roman Borisov <ext-roman.borisov@nokia.com>
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Hello,

Could you clarify is there a bug in fs/ext4/namei.c,
ext4_dx_find_entry() and fs/ext4/namei.c, ext3_dx_find_entry()?

<code>
static struct buffer_head * ext3_dx_find_entry(struct inode *dir,
...
struct dx_hash_info hinfo;
...
if (namelen > 2 || name[0] != '.'|| (namelen == 2 && name[1] != '.')) {
if (!(frame = dx_probe(entry, dir, &hinfo, frames, err)))
return NULL;
} else {
frame = frames;
frame->bh = NULL; /* for dx_release() */
frame->at = (struct dx_entry *)frames; /* hack for zero entry*/
dx_set_block(frame->at, 0); /* dx_root block is 0 */
}
hash = hinfo.hash;
...
retval = ext3_htree_next_block(dir, hash, frame,
...
</code>

In the code above: hinfo.hash is not initialized in "else" case.
Should it be initialized as NULL?
Or maybe implementation doesn't assume to call ext3_htree_next_block()
in such case?

Thanks,
Roman