Re: [PATCH] kvm: fix memory leak on failure to read stats descriptors

[Richard Henderson <richard.henderson@linaro.org>]

On 9/5/22 11:06, Paolo Bonzini wrote:
> Reported by Coverity as CID 1490142.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   accel/kvm/kvm-all.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 7c8ce18bdd..208b0c74e3 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -3962,6 +3962,7 @@ static StatsDescriptors *find_stats_descriptors(StatsTarget target, int stats_fd
>                      size_desc * kvm_stats_header->num_desc, ret);
>           g_free(descriptors);
>           g_free(kvm_stats_desc);
> +        g_free(kvm_stats_header);
>           return NULL;
>       }

kvm_stats_header should also be freed just above, in the other read failure if block.

Alternately, can StatsDescriptors be reorg'ed as

   typedef struct StatsDescriptors {

       const char *ident; /* cache key, currently the StatsTarget */

       struct kvm_stats_desc *kvm_stats_desc;

-     struct kvm_stats_header *kvm_stats_header;
+     struct kvm_stats_header kvm_stats_header;
       QTAILQ_ENTRY(StatsDescriptors) next;

   } StatsDescriptors;


since it appears that kvm_stats_header has the same lifetime as the descriptor, and is not 
variable sized, like kvm_stats_desc.


r~