[libvirt] [PATCH] storage: Avoid leak in virStorageUtilGlusterExtractPoolSources()

[John Ferlan]

On 04/05/2017 12:28 PM, Andrea Bolognani wrote:
> The contents of volname would be leaked if the function were
> to be passed an invalid pooltype by the caller.
> 
> Make sure the memory is released instead.
> ---
> Initializing volname to NULL is strictly speaking not
> necessary, but I like it better that way :)
> 
>  src/storage/storage_util.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 

This could be "as easy as" just adding a VIR_FREE(volname) in the "}
else {" case prior to virReportError and goto cleanup;


If you went with this option, then VIR_STEAL_PTR(src->dir, volname); and
VIR_STEAL_PTR(src->name, volname); instead of inlining.

And as some would say the comment is "obvious".

IDC which way it happens...

John

> diff --git a/src/storage/storage_util.c b/src/storage/storage_util.c
> index 7cc125a..e0f948b 100644
> --- a/src/storage/storage_util.c
> +++ b/src/storage/storage_util.c
> @@ -2846,7 +2846,7 @@ virStorageUtilGlusterExtractPoolSources(const char *host,
>      xmlXPathContextPtr ctxt = NULL;
>      xmlNodePtr *nodes = NULL;
>      virStoragePoolSource *src = NULL;
> -    char *volname;
> +    char *volname = NULL;
>      size_t i;
>      int nnodes;
>      int ret = -1;
> @@ -2871,12 +2871,17 @@ virStorageUtilGlusterExtractPoolSources(const char *host,
>  
>          if (pooltype == VIR_STORAGE_POOL_NETFS) {
>              src->format = VIR_STORAGE_POOL_NETFS_GLUSTERFS;
> +
> +            /* Ownership of volname is passed to src */
>              src->dir = volname;
> +            volname = NULL;
>          } else if (pooltype == VIR_STORAGE_POOL_GLUSTER) {
> -            src->name = volname;
> -
>              if (VIR_STRDUP(src->dir, "/") < 0)
>                  goto cleanup;
> +
> +            /* Ownership of volname is passed to src */
> +            src->name = volname;
> +            volname = NULL;
>          } else {
>              virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
>                             _("unsupported gluster lookup"));
> @@ -2894,6 +2899,7 @@ virStorageUtilGlusterExtractPoolSources(const char *host,
>      ret = nnodes;
>  
>   cleanup:
> +    VIR_FREE(volname);
>      VIR_FREE(nodes);
>      xmlXPathFreeContext(ctxt);
>      xmlFreeDoc(doc);
>