patch 9.0.2143: [security]: buffer-overflow in ex_substitute Commit: https://github.com/vim/vim/commit/abfa13ebe92d81aaf66669c428d767847b577453 Author: Christian Brabandt <cb@256bit.org> Date: Thu Nov 30 11:32:18 2023 +0100 patch 9.0.2143: [security]: buffer-overflow in ex_substitute Problem: [security]: buffer-overflow in ex_substitute Solution: clear memory after allocating When allocating the new_start pointer in ex_substitute() the memory pointer points to some garbage that the following for loop in ex_cmds.c:4743 confuses and causes it to accessing the new_start pointer beyond it's size, leading to a buffer-overlow. So fix this by using alloc_clear() instead of alloc(), which will clear the memory by NUL and therefore cause the loop to terminate correctly. Reported by @henices, thanks! closes: #13596 Signed-off-by: Christian Brabandt <cb@256bit.org>