main/dnsmasq: backport patches for CVE-2017-14491..14496

1 files changed, 41 insertions, 0 deletions

diff --git a/main/dnsmasq/CVE-2017-14495.patch b/main/dnsmasq/CVE-2017-14495.patch
new file mode 100644
index 00000000000..7aad2b3de8a
--- /dev/null
+++ b/main/dnsmasq/CVE-2017-14495.patch
@@ -0,0 +1,41 @@
+From 51eadb692a5123b9838e5a68ecace3ac579a3a45 Mon Sep 17 00:00:00 2001
+From: Simon Kelley <simon@thekelleys.org.uk>
+Date: Mon, 25 Sep 2017 20:16:50 +0100
+Subject: [PATCH] Security fix, CVE-2017-14495, OOM in DNS response
+ creation.
+
+Fix out-of-memory Dos vulnerability. An attacker which can
+send malicious DNS queries to dnsmasq can trigger memory
+allocations in the add_pseudoheader function
+The allocated memory is never freed which leads to a DoS
+through memory exhaustion. dnsmasq is vulnerable only
+if one of the following option is specified:
+--add-mac, --add-cpe-id or --add-subnet.
+---
+ src/edns0.c | 8 +++++++-
+ 1 file changed, 7 insertions(+), 1 deletion(-)
+
+diff --git a/src/edns0.c b/src/edns0.c
+index 95b74ee..89b2692 100644
+--- a/src/edns0.c
++++ b/src/edns0.c
+@@ -192,9 +192,15 @@ size_t add_pseudoheader(struct dns_header *header, size_t plen, unsigned char *l
+ 	  !(p = skip_section(p, 
+ 			     ntohs(header->ancount) + ntohs(header->nscount) + ntohs(header->arcount), 
+ 			     header, plen)))
++      {
++	free(buff);
+ 	return plen;
++      }
+       if (p + 11 > limit)
+-       return plen; /* Too big */
++      {
++        free(buff);
++        return plen; /* Too big */
++      }
+       *p++ = 0; /* empty name */
+       PUTSHORT(T_OPT, p);
+       PUTSHORT(udp_sz, p); /* max packet length, 512 if not given in EDNS0 header */
+-- 
+2.9.5
+