[BUG] Unchecked strdup return value in matroska.c

[Anayo-Anyafulu]

Summary

In parse_segment_track_entry() in src/lib_ccx/matroska.c, strdup("eng") on line 866 is called without checking for NULL. If allocation fails, lang will be NULL and could cause issues if dereferenced before reassignment.

Code

Line 866: char *lang = strdup("eng");

Suggested Fix

Add a NULL check and call fatal(EXIT_NOT_ENOUGH_MEMORY, ...) if strdup returns NULL.