Re: [PATCH v1] tools/libs/guest: assist gcc13's realloc analyzer

[Jason Andryuk <jandryuk@xxxxxxxxx>]

On Wed, Apr 19, 2023 at 8:55 AM Juergen Gross <jgross@xxxxxxxx> wrote:
>
> On 19.04.23 12:06, Olaf Hering wrote:
> > gcc13 fails to track the allocated memory in backup_ptes:
> >
> > xg_offline_page.c: In function 'backup_ptes':
> > xg_offline_page.c:191:13: error: pointer 'orig' may be used after 'realloc' 
> > [-Werror=use-after-free]
> >    191 |             free(orig);
> >
> > Assist the analyzer by slightly rearranging the code:
> > In case realloc succeeds, the previous allocation is either extended
> > or released internally. In case realloc fails, the previous allocation
> > is left unchanged. Return an error in this case, the caller will
> > release the currently allocated memory in its error path.
> >
> > http://bugzilla.suse.com/show_bug.cgi?id=1210570
> >
> > Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
>
> Reviewed-by: Juergen Gross <jgross@xxxxxxxx>

Compile-tested-by: Jason Andryuk <jandryuk@xxxxxxxxx>

Needed to build on Fedora 38.

Thanks,
Jason