File libtasn1-CVE-2016-4008-2.patch of Package libtasn1.11138
From a6e0a0b58f5cdaf4e9beca5bce69c09808cbb625 Mon Sep 17 00:00:00 2001
From: Nikos Mavrogiannopoulos <nmav@redhat.com>
Date: Wed, 6 Apr 2016 13:02:19 +0200
Subject: [PATCH 1/1] _asn1_extract_der_octet: properly account the bytes read
through indefinite encodings
This prevents infinite recursions in the function loop.
Reported by Pascal Cuoq.
---
lib/decoding.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
Index: libtasn1-3.7/lib/decoding.c
===================================================================
--- libtasn1-3.7.orig/lib/decoding.c
+++ libtasn1-3.7/lib/decoding.c
@@ -665,7 +665,7 @@ _asn1_delete_not_used (asn1_node node)
static int
_asn1_extract_der_octet (asn1_node node, const unsigned char *der,
- int der_len)
+ int der_len, int *bytes)
{
int len2, len3;
int counter, counter_end;
@@ -708,15 +708,19 @@ _asn1_extract_der_octet (asn1_node node,
DECR_LEN(der_len, len3);
result =
_asn1_extract_der_octet (node, der + counter + len3,
- der_len);
+ der_len, &len2);
if (result != ASN1_SUCCESS)
return result;
- len2 = 0;
+
+ DECR_LEN(der_len, len2);
}
counter += len2 + len3 + 1;
}
+ if (bytes)
+ *bytes = counter;
+
return ASN1_SUCCESS;
cleanup:
@@ -785,7 +789,7 @@ _asn1_get_octet_string (asn1_node node,
asn1_length_der (tot_len, temp, &len2);
_asn1_set_value (node, temp, len2);
- ret = _asn1_extract_der_octet (node, der, der_len);
+ ret = _asn1_extract_der_octet (node, der, der_len, NULL);
if (ret != ASN1_SUCCESS)
return ret;