[libvirt] [PATCH] vbox_tmpl.c: avoid leak on OOM error path

[Matthias Bolte]

2010/2/15 Jim Meyering <jim at meyering.net>:
> We have to free def here, rather than after "cleanup:",
> because "cleanup:" is on the successful-return path.
>
> >From 2c7800c3560f03fd77e4a458cb0e557165faed3f Mon Sep 17 00:00:00 2001
> From: Jim Meyering <meyering at redhat.com>
> Date: Mon, 15 Feb 2010 17:54:15 +0100
> Subject: [PATCH] vbox_tmpl.c: avoid leak on OOM error path
>
> * src/vbox/vbox_tmpl.c (vboxDomainDumpXML): Free def upon virAsprintf
> failure.
> ---
>  src/vbox/vbox_tmpl.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/src/vbox/vbox_tmpl.c b/src/vbox/vbox_tmpl.c
> index 68dffd2..1fb8d56 100644
> --- a/src/vbox/vbox_tmpl.c
> +++ b/src/vbox/vbox_tmpl.c
> @@ -6059,14 +6059,15 @@ static char *vboxNetworkDumpXML(virNetworkPtr network, int flags ATTRIBUTE_UNUSE
>     if (VIR_ALLOC(def) < 0) {
>         virReportOOMError();
>         goto cleanup;
>     }
>
>     if (virAsprintf(&networkNameUtf8, "HostInterfaceNetworking-%s", network->name) < 0) {
>         virReportOOMError();
> +        VIR_FREE(def);
>         goto cleanup;
>     }
>
>     PRUnichar *networkInterfaceNameUtf16    = NULL;
>     IHostNetworkInterface *networkInterface = NULL;
>
>     VBOX_UTF8_TO_UTF16(network->name, &networkInterfaceNameUtf16);
> --
> 1.7.0.181.g41533
>

If you look closely at what the function does with the
virNetworkDefPtr def, you see that it fills it with information and
calls virNetworkDefFormat in the end. So def is never returned from
the function and leaks in the successful-return path. I suggest this
patch instead:

diff --git a/src/vbox/vbox_tmpl.c b/src/vbox/vbox_tmpl.c
index 68dffd2..d1a701e 100644
--- a/src/vbox/vbox_tmpl.c
+++ b/src/vbox/vbox_tmpl.c
@@ -6183,6 +6183,7 @@ static char *vboxNetworkDumpXML(virNetworkPtr
network, int flags ATTRIBUTE_UNUSE
     ret = virNetworkDefFormat(def);

 cleanup:
+    virNetworkDefFree(def);
     VIR_FREE(networkNameUtf8);
     return ret;
 }


Matthias