linux-ext4 - Re: New compiler warning in 2.6.34-rc1: 'start_ext.ee

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100315154142.GB4484@thunk.org>
Date:	Mon, 15 Mar 2010 11:41:42 -0400
From:	tytso@....edu
To:	Stefan Richter <stefanr@...6.in-berlin.de>
Cc:	Akira Fujita <a-fujita@...jp.nec.com>, linux-ext4@...r.kernel.org
Subject: Re: New compiler warning in 2.6.34-rc1: 'start_ext.ee_block' may
 be used uninitialized

On Mon, Mar 15, 2010 at 03:42:39PM +0100, Stefan Richter wrote:
> Hi,
> 
> I saw the following scroll by during kernel compilation:
> 
> fs/ext4/move_extent.c: In function 'mext_leaf_block':
> 
> fs/ext4/move_extent.c:478: warning: 'start_ext.ee_block' may be used
> uninitialized in this function
> 
> Is it real?  It seems that the initial start_ext.ee_len = 0 guards
> against accidental use of an uninitialized start_ext.ee_block, but maybe
> I missed something.

>From my review of the code the fact that ee_len is set to zero should
make this be safe, but my preference would be to clear
start_ext.ee_block as well to prevent the warning from coming up
(since false positives clutter up warnings and might cause us to miss
a warning which isn't so benign).

Akira-san, do you agree that it is currently is safe?

	      	  	     	   - Ted
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html