Free zone name when destroying malloc zone

[fjricci]

Summary

The darwin interceptor for malloc_destroy_zone manually frees the
zone struct, but does not free the name component. Make sure to
free the name if it has been set.

[alekseyshl]

lib/sanitizer_common/sanitizer_malloc_mac.inc

62

Nit: prefer no brackets for one liners

[fjricci]

lib/sanitizer_common/sanitizer_malloc_mac.inc

62

Even for macros?

[alekseyshl]

lib/sanitizer_common/sanitizer_malloc_mac.inc

62

Ha, you're right, COMMON_MALLOC_FREE is . I was assuming multiline macro supposed to do this "do {} while (0)" trick. Anyway, ignore this nit.

[fjricci]

lib/sanitizer_common/sanitizer_malloc_mac.inc

62

Yeah, it may be worth looking into fixing up our macros to use do/while in the future.

lib/sanitizer_common/sanitizer_malloc_mac.inc

INTERCEPTOR(void, malloc_destroy_zone, malloc_zone_t *zone) {
   COMMON_MALLOC_ENTER();
   // We don't need to do anything here.  We're not registering new zones, so we
   // don't to unregister.  Just un-mprotect and free() the zone.
   if (GetMacosVersion() >= MACOS_VERSION_LION) {
     uptr page_size = GetPageSizeCached();
     uptr allocated_size = RoundUpTo(sizeof(sanitizer_zone), page_size);
     mprotect(zone, allocated_size, PROT_READ | PROT_WRITE);
   }
+  if (zone->zone_name) {
+    COMMON_MALLOC_FREE((void *)zone->zone_name);
+  }
   COMMON_MALLOC_FREE(zone);
 }
 
 extern unsigned malloc_num_zones;
 extern malloc_zone_t **malloc_zones;
 
 // We need to make sure that sanitizer_zone is registered as malloc_zones[0]. If
 // libmalloc tries to set up a different zone as malloc_zones[0], it will call