svn commit: r350635 - head/contrib/bsnmp/lib

[Ed Maste]

Author: emaste
Date: Tue Aug  6 16:09:06 2019
New Revision: 350635
URL: https://svnweb.freebsd.org/changeset/base/350635

Log:
  bsnmp: add asn1 message length validation
  
  admbugs:	780
  Submitted by:	Guido Vranken, bz
  Reported by:	Guido Vranken
  Security:	CVE-2019-5610

Modified:
  head/contrib/bsnmp/lib/asn1.c

Modified: head/contrib/bsnmp/lib/asn1.c
==============================================================================
--- head/contrib/bsnmp/lib/asn1.c	Tue Aug  6 14:39:02 2019	(r350634)
+++ head/contrib/bsnmp/lib/asn1.c	Tue Aug  6 16:09:06 2019	(r350635)
@@ -100,6 +100,11 @@ asn_get_header(struct asn_buf *b, u_char *type, asn_le
 		*len = *b->asn_cptr++;
 		b->asn_len--;
 	}
+	if (*len > b->asn_len) {
+		asn_error(b, "len %u exceeding asn_len %u", *len, b->asn_len);
+		return (ASN_ERR_EOBUF);
+	}
+	
 	return (ASN_ERR_OK);
 }