Re: [PATCH] ext3: Fix not initialized hash info in ext3_dx_find_entry()

[FNST-Wang Chen <wangchen@cn.fujitsu.com>]

Agree, thanks.

Theodore Tso said the following on 2007-8-30 23:29:
> On Thu, Aug 30, 2007 at 10:42:33PM +0800, Wang Chen wrote:
>   
>> +               if (dentry){
>> +                       ext3fs_dirhash(dentry->d_name.name, 
>> dentry->d_name.len,
>> +                                      &hinfo);
>> +               } else {
>> +                       return NULL;
>> +               }
>>     
>
> It's really not necessary to call ext3fs_dirhash(), since we don't
> need the hash value for the '.' and '..' case.  So here's a better
> patch....
>
>      	      	    	    	- Ted
>
> >From c2ff518e6f529f1d8b627f0e8be5d6f8af32747f Mon Sep 17 00:00:00 2001
> From: Theodore Ts'o <tytso@mit.edu>
> Date: Thu, 30 Aug 2007 11:26:24 -0400
> Subject: [PATCH] ext3: Fix use of uninitialized variable in ext3_dx_find_entry()
>
> In the case where we are looking up '.' and '..', those files are
> always in the first directory block, so we don't need worry about the
> hash value.  This avoids a lint warning message, as a minor cleanup.
>
> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
> ---
>  fs/ext3/namei.c |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/ext3/namei.c b/fs/ext3/namei.c
> index 1586807..c278fc7 100644
> --- a/fs/ext3/namei.c
> +++ b/fs/ext3/namei.c
> @@ -932,7 +932,7 @@ static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
>  {
>  	struct super_block * sb;
>  	struct dx_hash_info	hinfo;
> -	u32 hash;
> +	u32 hash = 0;
>  	struct dx_frame frames[2], *frame;
>  	struct ext3_dir_entry_2 *de, *top;
>  	struct buffer_head *bh;
> @@ -947,13 +947,13 @@ static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
>  	if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
>  		if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
>  			return NULL;
> +		hash = hinfo.hash;
>  	} 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;
>  	do {
>  		block = dx_get_block(frame->at);
>  		if (!(bh = ext3_bread (NULL,dir, block, 0, err)))
>   


-- 
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