Re: [2.6.19 patch] drivers/block/aoe/aoedev.c: fix NULL dereference

[Adrian Bunk <bunk@stusta.de>]

On Wed, Nov 01, 2006 at 11:36:28AM -0500, Ed L. Cashin wrote:
> On Wed, Nov 01, 2006 at 01:40:25AM +0100, Adrian Bunk wrote:
> > This patch fixes a NULL dereference introduced by
> > commit e407a7f6cd143b3ab4eb3d7e1cf882e96b710eb5:
> > 
> > This quite unusual error handling through a switch introduces NULL 
> > dereferences if exactly one of the two k{c,z}alloc's failed.
> 
> Hmm.  If exactly one of the two fails, then the value of the switch
> conditional is 1 (well, certainly not zero).  It will jump over the
> zero case, and there's a return in the default case, so I'm having
> trouble seeing the danger.
> 
> What exactly is Coverity saying?  That would be interesting to know.

The Coverity checker was wrong in this case, and I didn't spot it when 
checking since the code is really confusing.

>   Ed L Cashin <ecashin@coraid.com>

cu
Adrian

-- 

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       "Only a promise," Lao Er said.
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