[PATCH v2 1/1] Fix use after free in vfio_migration_probe

[PATCH v2 1/1] Fix use after free in vfio_migration_probe

[Kirti Wankhede]

Fixes Coverity issue:
CID 1436126:  Memory - illegal accesses  (USE_AFTER_FREE)

Fixes: a9e271ec9b36 ("vfio: Add migration region initialization and finalize
function")

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: David Edmondson <dme@dme.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 hw/vfio/migration.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 3ce285ea395d..55261562d4f3 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -897,8 +897,8 @@ int vfio_migration_probe(VFIODevice *vbasedev, Error **errp)
         goto add_blocker;
     }
 
-    g_free(info);
     trace_vfio_migration_probe(vbasedev->name, info->index);
+    g_free(info);
     return 0;
 
 add_blocker:
-- 
2.7.0

Re: [PATCH v2 1/1] Fix use after free in vfio_migration_probe

[Peter Maydell]

On Fri, 6 Nov 2020 at 18:35, Kirti Wankhede <kwankhede@nvidia.com> wrote:
>
> Fixes Coverity issue:
> CID 1436126:  Memory - illegal accesses  (USE_AFTER_FREE)
>
> Fixes: a9e271ec9b36 ("vfio: Add migration region initialization and finalize
> function")
>
> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> Reviewed-by: David Edmondson <dme@dme.org>
> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---

Hi Alex -- this is a fix for a Coverity issue, are you planning
a pullreq with it in? It would be nice to have it in rc2 next week.

thanks
-- PMM

Re: [PATCH v2 1/1] Fix use after free in vfio_migration_probe

[Alex Williamson]

On Thu, 12 Nov 2020 15:57:46 +0000
Peter Maydell <peter.maydell@linaro.org> wrote:

> On Fri, 6 Nov 2020 at 18:35, Kirti Wankhede <kwankhede@nvidia.com> wrote:
> >
> > Fixes Coverity issue:
> > CID 1436126:  Memory - illegal accesses  (USE_AFTER_FREE)
> >
> > Fixes: a9e271ec9b36 ("vfio: Add migration region initialization and finalize
> > function")
> >
> > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
> > Reviewed-by: David Edmondson <dme@dme.org>
> > Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> > Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> > ---  
> 
> Hi Alex -- this is a fix for a Coverity issue, are you planning
> a pullreq with it in? It would be nice to have it in rc2 next week.

Hi Peter,

Yes, I was planning to send a pull request.  It's a trivial and obvious
fix, so if by chance you'd like to grab it separately, you're also more
than welcome.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>

Thanks,
Alex