Re: [libvirt] [libvirt-php][PATCH 2/3] Fix some leaks related to get_string_from_xpath

On 19.04.2016 16:09, Christophe Fergeau wrote: > On Tue, Apr 19, 2016 at 03:46:41PM +0200, Michal Privoznik wrote: >> This function not only did not free return value of >> xmlNodeListGetString() it strdup()-ed its return value. Therefore >> plenty of memory has been lost definitely upon return from this >> function. >> >> Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; >> --- >> src/libvirt-php.c | 110 ++++++++++++++++++++++++++++++------------------------ >> 1 file changed, 62 insertions(+), 48 deletions(-) >> >> diff --git a/src/libvirt-php.c b/src/libvirt-php.c >> index 308e764..fb0679b 100644 >> --- a/src/libvirt-php.c >> +++ b/src/libvirt-php.c >> @@ -3232,19 +3232,17 @@ char *get_string_from_xpath(char *xml, char *xpath, zval **val, int *retVal) >> if (val != NULL) { >> ret = 0; >> for (i = 0; i < nodeset->nodeNr; i++) { >> - if (xmlNodeListGetString(doc, nodeset->nodeTab[i]->xmlChildrenNode, 1) != NULL) { >> - value = (char *)xmlNodeListGetString(doc, nodeset->nodeTab[i]->xmlChildrenNode, 1); >> - >> + if ((value = xmlNodeListGetString(doc, nodeset->nodeTab[i]->xmlChildrenNode, 1))) { >> snprintf(key, sizeof(key), "%d", i); >> VIRT_ADD_ASSOC_STRING(*val, key, value); >> + free(value); >> + value = NULL; > > 'value' is an xmlChar so must be freed with xmlFree. I'd change the > return value of get_string_from_xpath() to make it clear that xmlFree needs to > be used to free it as well. > Yeah, I could not agree more. But problem is that would be a great patch. Moreover, xmlFree() == free() unless some debug is turned on in libxml2 during its compilation. And since Vasiliy will make this function go away, I'd rather push this as is.