[libvirt] [PATCH 1/5] virDomainNumaGetNodeDistance: Fix input arguments validation

[John Ferlan]

On 11/14/2017 09:47 AM, Michal Privoznik wrote:
> There's no point in checking if numa->mem_nodes[node].ndistances
> is set if we check for numa->mem_nodes[node].distances. However,
> it makes sense to check if the sibling node caller passed falls
> within boundaries.
> 
> Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
> ---
>  src/conf/numa_conf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/conf/numa_conf.c b/src/conf/numa_conf.c
> index 7bba4120b..5f0b3f9ed 100644
> --- a/src/conf/numa_conf.c
> +++ b/src/conf/numa_conf.c
> @@ -1154,7 +1154,7 @@ virDomainNumaGetNodeDistance(virDomainNumaPtr numa,
>       */
>      if (!distances ||
>          !distances[cellid].value ||
> -        !numa->mem_nodes[node].ndistances)
> +        node >= numa->nmem_nodes)

If @distances can only be set if "node < numa->nmem_nodes", then how
could "node >= numa->nmem_nodes" ever be true and @distances be non
NULL?  IOW: I see no need for the check... This former condition also
trips across my "favorite" condition check of "if !intValue"
substituting for "if intValue == 0" <sigh>.

BTW: I do think there is a memory leak @distances entries are not
VIR_FREE'd in virDomainNumaFree. I was looking for instances where
ndistances maybe have been forgotten to be set to 0 even though
distances was cleared.  I can send a patch or you can for that if you
want - IDC...  There's a couple of other cleanups I'd like to see w/r/t
using (!*ndistances) and how the @*distance are set to ldist/rdist
outside of the if condition that allocated, but those are type A type
things ;-)

John

>          return (node == cellid) ? LOCAL_DISTANCE : REMOTE_DISTANCE;
>  
>      return distances[cellid].value;
>