jcs
/subtext
/amendments
/252
util: panic on xfree(NULL) and xfree(&NULL)
jcs made amendment 252 about 1 year ago
--- util.c Tue Sep 13 21:31:54 2022
+++ util.c Fri Sep 16 17:56:10 2022
@@ -203,10 +203,19 @@ void
xfree(void *ptrptr)
{
unsigned long *addr = (unsigned long *)ptrptr;
- void *ptr = (void *)*addr;
+ void *ptr;
#ifdef MALLOC_DEBUG
unsigned long n;
+#endif
+ if (ptrptr == NULL)
+ panic("xfree(NULL)");
+
+ ptr = (void *)*addr;
+ if (ptr == NULL)
+ panic("xfree(&NULL) likely a double-free");
+
+#ifdef MALLOC_DEBUG
for (n = 0; n <= malloc_map_size; n++) {
if (n == malloc_map_size)
panic("xfree(0x%lx): can't find in alloc map, likely "