From: Daniel Stenberg <daniel@haxx.se>
Date: Sat, 16 Sep 2023 20:37:28 +0000 (+0200)
Subject: rand: fix 'alnum': array is too small to include a terminating null character
X-Git-Tag: curl-8_4_0~187
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=706eff9f1f144e6c9a1ed9c9646007760921cf67;p=thirdparty%2Fcurl.git

rand: fix 'alnum': array is too small to include a terminating null character

It was that small on purpose, but this change now adds the null byte to
avoid the error.

Follow-up to 3aa3cc9b052353b1

Reported-by: Dan Fandrich
Ref: #11838
Closes #11870
---

diff --git a/lib/rand.c b/lib/rand.c
index 8cac9383ac..d7935b397e 100644
--- a/lib/rand.c
+++ b/lib/rand.c
@@ -275,14 +275,14 @@ CURLcode Curl_rand_hex(struct Curl_easy *data, unsigned char *rnd,
  * alphanumerical chars PLUS a null-terminating byte.
  */
 
-static const char alnum[26 + 26 + 10] =
+static const char alnum[] =
   "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
 
 CURLcode Curl_rand_alnum(struct Curl_easy *data, unsigned char *rnd,
                          size_t num)
 {
   CURLcode result = CURLE_OK;
-  const int alnumspace = sizeof(alnum);
+  const int alnumspace = sizeof(alnum) - 1;
   unsigned int r;
   DEBUGASSERT(num > 1);