Re: [PATCH] x86/sgx: fix a NULL pointer

[Huang, Kai]

On Wed, 2023-07-19 at 08:53 -0500, Haitao Huang wrote:
> Hi Dave and Kai
> On Tue, 18 Jul 2023 19:21:54 -0500, Dave Hansen <dave.hansen@xxxxxxxxx>  
> wrote:
> 
> > On 7/18/23 17:14, Huang, Kai wrote:
> > > Also perhaps the patch title is too vague.  Adding more information  
> > > doesn't hurt
> > > I think, e.g., mentioning it is a fix for NULL pointer dereference in  
> > > the EAUG
> > > flow.
> > 
> > Yeah, let's say something like:
> > 
> > 	x86/sgx: Resolve SECS reclaim vs. page fault race
> > 
> The patch is not to resolve SECS vs #PF race though the race is a  
> necessary condition to cause the NULL pointer. The same condition does not  
> cause NULL pointer in the ELDU path of #PF, only in EAUG path of #PF.
> 
> And the issue really is the NULL pointer not checked and fix was to reuse  
> the same code to reload SECS in ELDU code path for EAUG code path
> 
> 
> How about this:
> 
> x86/sgx:  Reload reclaimed SECS for EAUG on #PF
> 
> or
> 
> x86/sgx: Fix a NULL pointer to SECS used for EAUG on #PF
> 

Perhaps you can add "EAUG" part to what Dave suggested?

	x86/sgx: Resolves SECS reclaim vs. page fault race on EAUG

(assuming Dave is fine with this :-))