And check the buffer size precisely.
@@ -225,6 +225,7 @@ ipv4_to_ptr(uint32_t ipv4, char ptr[], size_t nm_len)
static const char IPV4_PTR_SUFFIX[] = "\07in-addr\04arpa";
int i;
char* c = ptr;
+ log_assert(nm_len == MAX_PTR_QNAME_IPV4);
for (i = 0; i < 4; ++i) {
*c = uitoa((unsigned int)(ipv4 % 256), c + 1);
