ticket: 6448

subject: CVE-2009-0846 (1.6.x) asn1_decode_generaltime can free uninitialized pointer
tags: pullup
target_version: 1.6.4
version_fixed: 1.6.4

pull up rxxxx from trunk

The asn1_decode_generaltime() function can free an uninitialized
pointer if asn1buf_remove_charstring() fails.

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-6@22181 dc483132-0cff-0310-8789-dd5450dbe970

src/lib/krb5/asn.1/asn1_decode.c

@@ -231,6 +231,7 @@ asn1_error_code asn1_decode_generaltime(asn1buf *buf, time_t *val)
 
   if(length != 15) return ASN1_BAD_LENGTH;
   retval = asn1buf_remove_charstring(buf,15,&s);
+  if (retval) return retval;
   /* Time encoding: YYYYMMDDhhmmssZ */
   if(s[14] != 'Z') {
       free(s);

src/tests/asn.1/krb5_decode_test.c

@@ -485,6 +485,22 @@ int main(argc, argv)
     ktest_destroy_keyblock(&(ref.subkey));
     ref.seq_number = 0;
     decode_run("ap_rep_enc_part","(optionals NULL)","7B 1C 30 1A A0 11 18 0F 31 39 39 34 30 36 31 30 30 36 30 33 31 37 5A A1 05 02 03 01 E2 40",decode_krb5_ap_rep_enc_part,ktest_equal_ap_rep_enc_part,krb5_free_ap_rep_enc_part);
+
+    retval = krb5_data_hex_parse(&code, "7B 06 30 04 A0 11 18 0F 31 39 39 34 30 36 31 30 30 36 30 33 31 37 5A A1 05 02 03 01 E2 40");
+    if (retval) {
+	com_err("krb5_decode_test", retval, "while parsing");
+	exit(1);
+    }
+    retval = decode_krb5_ap_rep_enc_part(&code, &var);
+    if (retval != ASN1_OVERRUN) {
+	printf("ERROR: ");
+    } else {
+	printf("OK: ");
+    }
+    printf("ap_rep_enc_part(optionals NULL + expect ASN1_OVERRUN for inconsistent length of timestamp)\n");
+    krb5_free_data_contents(test_context, &code);
+    if (!retval) krb5_free_ap_rep_enc_part(test_context, var);
+
     ktest_empty_ap_rep_enc_part(&ref);
   }