From b0d1c5805a6b76c3b198728cdfd93e351d5eb196 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Thu, 28 Jan 2016 01:16:31 +0000 Subject: [PATCH] Fix memory leak in dhcpv6_add_server_cand in case odhcp6c_insert_state fails If we fail to store information from the new server, the associated NA and PD options will never be freed. An attacker could use this for denial-of-service. Signed-off-by: Ben Hutchings --- src/dhcpv6.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/dhcpv6.c b/src/dhcpv6.c index cfa3f29..c2a3e3d 100644 --- a/src/dhcpv6.c +++ b/src/dhcpv6.c @@ -1362,6 +1362,7 @@ static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig, } } +// Note this always takes ownership of cand->ia_na and cand->ia_pd static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand) { size_t cand_len, i; @@ -1384,7 +1385,10 @@ static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand *cand) break; } - odhcp6c_insert_state(STATE_SERVER_CAND, i * sizeof(*c), cand, sizeof(*cand)); + if (odhcp6c_insert_state(STATE_SERVER_CAND, i * sizeof(*c), cand, sizeof(*cand))) { + free(cand->ia_na); + free(cand->ia_pd); + } } static void dhcpv6_clear_all_server_cand(void) -- 2.39.2