From 099016b7e8d70a6d5dd814e788bba08d33d48426 Mon Sep 17 00:00:00 2001 From: Tobias Stoeckmann Date: Mon, 4 May 2020 19:41:16 +0200 Subject: [PATCH] Protect array_list_del_idx against size_t overflow. If the assignment of stop overflows due to idx and count being larger than SIZE_T_MAX in sum, out of boundary access could happen. It takes invalid usage of this function for this to happen, but I decided to add this check so array_list_del_idx is as safe against bad usage as the other arraylist functions. --- arraylist.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arraylist.c b/arraylist.c index 12ad8af..e5524ac 100644 --- a/arraylist.c +++ b/arraylist.c @@ -136,6 +136,9 @@ int array_list_del_idx(struct array_list *arr, size_t idx, size_t count) { size_t i, stop; + /* Avoid overflow in calculation with large indices. */ + if (idx > SIZE_T_MAX - count) + return -1; stop = idx + count; if (idx >= arr->length || stop > arr->length) return -1; -- 2.40.0