From b3a0437dec8faa42aed427bdab02cb82d86ba1a3 Mon Sep 17 00:00:00 2001 From: Sean Bright Date: Tue, 8 Oct 2024 15:11:05 -0400 Subject: [PATCH] func_base64.c: Ensure we set aside enough room for base64 encoded data. Reported by SingularTricycle on IRC. Fixes #940 (cherry picked from commit 7c359a2dd347ff6efa674a0f602105de0aa48443) --- funcs/func_base64.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/funcs/func_base64.c b/funcs/func_base64.c index 136a36147a..c9d30b8c0c 100644 --- a/funcs/func_base64.c +++ b/funcs/func_base64.c @@ -85,7 +85,10 @@ static int base64_helper(struct ast_channel *chan, const char *cmd, char *data, ast_base64encode(buf, (unsigned char *) data, strlen(data), len); } else { if (len >= 0) { - ast_str_make_space(str, len ? len : ast_str_strlen(*str) + strlen(data) * 4 / 3 + 2); + /* This calculation accounts for padding and the trailing 0 byte. Borrowed + from utils.c */ + size_t bytes_needed_to_encode_data = ((strlen(data) * 4 / 3 + 3) & ~3) + 1; + ast_str_make_space(str, len ? len : ast_str_strlen(*str) + bytes_needed_to_encode_data); } ast_base64encode(ast_str_buffer(*str) + ast_str_strlen(*str), (unsigned char *) data, strlen(data), ast_str_size(*str) - ast_str_strlen(*str)); ast_str_update(*str); -- 2.47.2