Plug leaks in ASN1_TIME_set_string_internal()

This API can be called with s == NULL, in which case the tm_to_*()
functions helpfully allocate a new s and then leak. This is a rather
ugly fix to make portable ASAN regress happy again, the better fix
will be to rewrite the tm_to_*() functions and adjust their callers.
That is more intrusive and will be done in a later pass.

ok bcook jsing

1 files changed, 17 insertions, 6 deletions

diff --git a/src/lib/libcrypto/asn1/a_time_tm.c b/src/lib/libcrypto/asn1/a_time_tm.c
index c8eabec08f..16b9df2584 100644
--- a/src/lib/libcrypto/asn1/a_time_tm.c
+++ b/src/lib/libcrypto/asn1/a_time_tm.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: a_time_tm.c,v 1.34 2024/04/08 19:57:40 beck Exp $ */
+/* $OpenBSD: a_time_tm.c,v 1.35 2024/04/09 13:56:00 tb Exp $ */
 /*
  * Copyright (c) 2015 Bob Beck <beck@openbsd.org>
  *
@@ -344,21 +344,32 @@ ASN1_time_parse(const char *bytes, size_t len, struct tm *tm, int mode)
 static int
 ASN1_TIME_set_string_internal(ASN1_TIME *s, const char *str, int mode)
 {
+        ASN1_TIME *atime = s;
         struct tm tm;
         int type;
+        int ret = 0;
 
         if ((type = ASN1_time_parse(str, strlen(str), &tm, mode)) == -1)
                 return (0);
-        switch(mode) {
+        switch (mode) {
         case V_ASN1_UTCTIME:
-                return (type == mode && tm_to_utctime(&tm, s) != NULL);
+                ret = (type == mode && (atime = tm_to_utctime(&tm, s)) != NULL);
+                break;
         case V_ASN1_GENERALIZEDTIME:
-                return (type == mode && tm_to_gentime(&tm, s) != NULL);
+                ret = (type == mode && (atime = tm_to_gentime(&tm, s)) != NULL);
+                break;
         case RFC5280:
-                return (tm_to_rfc5280_time(&tm, s) != NULL);
+                ret = ((atime = tm_to_rfc5280_time(&tm, s)) != NULL);
+                break;
         default:
-                return (0);
+                ret = 0;
+                break;
         }
+
+        if (atime != s)
+                ASN1_TIME_free(atime);
+
+        return ret;
 }
 
 static ASN1_TIME *