From: Simon Arlott <sa.me.uk>
Date: Thu, 24 Sep 2020 22:03:14 +0000 (+0100)
Subject: gen_pkcs3: Terminate string before calling BH_hex2bn()
X-Git-Tag: exim-4.95-RC0~51^2~51
X-Git-Url: https://git.exim.org/exim.git/commitdiff_plain/17218ac718eb00d616c131ad40f1875e43254d5c?ds=sidebyside

gen_pkcs3: Terminate string before calling BH_hex2bn()

Signed-off-by: Phil Pennock <pdp@exim.org>
(cherry picked from commit 1cf66e5872d517b620c308af634e4e26e3547f06)
(cherry picked from commit 48d8c54ecf9493c709d4305850877b6062f285a7)
---

diff --git a/src/util/gen_pkcs3.c b/src/util/gen_pkcs3.c
index 6a467e07a..5c4e42993 100644
--- a/src/util/gen_pkcs3.c
+++ b/src/util/gen_pkcs3.c
@@ -54,7 +54,6 @@ void __attribute__((__noreturn__))
 die_openssl_err(const char *msg)
 {
   char err_string[250];
-  unsigned long e;
 
   ERR_error_string_n(ERR_get_error(), err_string, sizeof(err_string));
   die("%s: %s", msg, err_string);
@@ -71,9 +70,9 @@ bn_from_text(const char *text)
   int rc;
 
   len = strlen(text);
-  spaceless = malloc(len);
+  spaceless = malloc(len + 1);
   if (!spaceless)
-    die("malloc(%zu) failed: %s", len, strerror(errno));
+    die("malloc(%zu) failed: %s", len + 1, strerror(errno));
 
   for (p = spaceless, q = text, end = text + len;
        q < end;
@@ -81,13 +80,15 @@ bn_from_text(const char *text)
     if (!isspace(*q))
       *p++ = *q;
   }
+  len = p - spaceless;
+  *p++ = '\0';
 
   b = NULL;
   rc = BN_hex2bn(&b, spaceless);
 
-  if (rc != p - spaceless)
+  if (rc != (int)len)
     die("BN_hex2bn did not convert entire input; took %d of %zu bytes",
-        rc, p - spaceless);
+        rc, len);
 
   return b;
 }