From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Antonio Quartulli Date: Wed, 18 May 2016 13:04:50 +0800 Message-Id: <1463547892-11290-7-git-send-email-a@unstable.cc> In-Reply-To: <1463547892-11290-1-git-send-email-a@unstable.cc> References: <1463547892-11290-1-git-send-email-a@unstable.cc> Subject: [B.A.T.M.A.N.] [PATCH 6/8] batman-adv: Fix integer overflow in batadv_iv_ogm_calc_tq List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: davem@davemloft.net Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, Antonio Quartulli , Marek Lindner , Sven Eckelmann From: Sven Eckelmann The undefined behavior sanatizer detected an signed integer overflow in a setup with near perfect link quality UBSAN: Undefined behaviour in net/batman-adv/bat_iv_ogm.c:1246:25 signed integer overflow: 8713350 * 255 cannot be represented in type 'int' The problems happens because the calculation of mixed unsigned and signed integers resulted in an integer multiplication. batadv_ogm_packet::tq (u8 255) * tq_own (u8 255) * tq_asym_penalty (int 134; max 255) * tq_iface_penalty (int 255; max 255) The tq_iface_penalty, tq_asym_penalty and inv_asym_penalty can just be changed to unsigned int because they are not expected to become negative. Fixes: c039876892e3 ("batman-adv: add WiFi penalty") Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/bat_iv_ogm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 1b5bbafc0fa3..ce2f203048d3 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -1180,9 +1180,10 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, u8 total_count; u8 orig_eq_count, neigh_rq_count, neigh_rq_inv, tq_own; unsigned int neigh_rq_inv_cube, neigh_rq_max_cube; - int tq_asym_penalty, inv_asym_penalty, if_num; + int if_num; + unsigned int tq_asym_penalty, inv_asym_penalty; unsigned int combined_tq; - int tq_iface_penalty; + unsigned int tq_iface_penalty; bool ret = false; /* find corresponding one hop neighbor */ -- 2.8.2