From 46b9670a418419d9e04bbe9a0d6c5a85f3c63265 Mon Sep 17 00:00:00 2001 From: Doran Moppert Date: Tue, 26 Sep 2017 14:48:20 +0930 Subject: [PATCH] google patch hand-applied --- src/edns0.c | 10 +++++----- src/rfc1035.c | 3 +++ 2 files changed, 8 insertions(+), 5 deletions(-) diff --git a/src/edns0.c b/src/edns0.c index c498eb1..0eb3873 100644 --- a/src/edns0.c +++ b/src/edns0.c @@ -212,11 +212,11 @@ size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *l /* Copy back any options */ if (buff) { - if (p + rdlen > limit) - { - free(buff); - return plen; /* Too big */ - } + if (p + rdlen > limit) + { + free(buff); + return plen; /* Too big */ + } memcpy(p, buff, rdlen); free(buff); p += rdlen; diff --git a/src/rfc1035.c b/src/rfc1035.c index 60ef272..93701f6 100644 --- a/src/rfc1035.c +++ b/src/rfc1035.c @@ -1411,6 +1411,9 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen, size_t len; int rd_bit = (header->hb3 & HB3_RD); + // Make sure we do not underflow here too. + if (qlen > (limit - ((char *)header))) return 0; + /* never answer queries with RD unset, to avoid cache snooping. */ if (ntohs(header->ancount) != 0 || ntohs(header->nscount) != 0 || -- 2.37.3