Tvheadend

FIX:

--- src/descrambler/descrambler.c.orig 2018-12-06 20:09:19.754402210 0100
++ src/descrambler/descrambler.c 2018-12-09 21:35:53.211691464 0100
@ -1282,7 +1282,8 @
}
if (des->last_data == NULL || len != des->last_data_len ||
memcmp(des->last_data, ptr, len)) {
- free(des->last_data);
if (des->last_data)
+ free(des->last_data);
des->last_data = malloc(len);
if (des->last_data) {
memcpy(des->last_data, ptr, len);

Good point!

I do not think it affects any platforms for which tvheadend is built.
[[https://stackoverflow.com/questions/1938735/does-freeptr-where-ptr-is-null-corrupt-memory]]

Why not:

diff --git a/src/descrambler/descrambler.c b/src/descrambler/descrambler.c
index 63b70b205..9b06bf6c1 100644
--- a/src/descrambler/descrambler.c
+++ b/src/descrambler/descrambler.c
@@ -1282,8 +1282,7 @@ descrambler_table_callback
     }
     if (des->last_data == NULL || len != des->last_data_len ||
         memcmp(des->last_data, ptr, len)) {
-      free(des->last_data);
-      des->last_data = malloc(len);
+      des->last_data = realloc(des->last_data, len);
       if (des->last_data) {
         memcpy(des->last_data, ptr, len);
         des->last_data_len = len;