From 33e3f1029c9ec6c63e430ff51063a6301d4b2262 Mon Sep 17 00:00:00 2001 From: Simon Kelley Date: Mon, 25 Sep 2017 20:05:11 +0100 Subject: [PATCH] Security fix, CVE-2017-14494, Infoleak handling DHCPv6 forwarded requests. Fix information leak in DHCPv6. A crafted DHCPv6 packet can cause dnsmasq to forward memory from outside the packet buffer to a DHCPv6 server when acting as a relay. CVE: CVE-2017-14494 Upstream-Status: Backport Signed-off-by: Sona Sarmadi --- CHANGELOG | 8 ++++++++ src/rfc3315.c | 3 +++ 2 files changed, 11 insertions(+) diff --git a/CHANGELOG b/CHANGELOG index c48378f..d1cc074 100644 --- a/CHANGELOG +++ b/CHANGELOG @@ -51,6 +51,14 @@ version 2.78 Credit to Felix Wilhelm, Fermin J. Serna, Gabriel Campana and Kevin Hamacher of the Google Security Team for finding this. + + Fix information leak in DHCPv6. A crafted DHCPv6 packet can + cause dnsmasq to forward memory from outside the packet + buffer to a DHCPv6 server when acting as a relay. + CVE-2017-14494 applies. + Credit to Felix Wilhelm, Fermin J. Serna, Gabriel Campana + and Kevin Hamacher of the Google Security Team for + finding this. version 2.77 diff --git a/src/rfc3315.c b/src/rfc3315.c index 920907c..4ca43e0 100644 --- a/src/rfc3315.c +++ b/src/rfc3315.c @@ -216,6 +216,9 @@ static int dhcp6_maybe_relay(struct state *state, void *inbuff, size_t sz, for (opt = opts; opt; opt = opt6_next(opt, end)) { + if (opt6_ptr(opt, 0) + opt6_len(opt) >= end) { + return 0; + } int o = new_opt6(opt6_type(opt)); if (opt6_type(opt) == OPTION6_RELAY_MSG) { -- 1.7.10.4