From 13bbdd370f67aef3351ad7bbc2fb624e3c23f905 Mon Sep 17 00:00:00 2001 From: Sven Eckelmann Date: Sun, 29 Nov 2015 01:48:57 +0100 Subject: [PATCH] batman-adv: Fix invalid read while copying bat_iv.bcast_own batadv_iv_ogm_orig_del_if removes a part of the bcast_own which previously belonged to the now removed interface. This is done by copying all data which comes before the removed interface and then appending all the data which comes after the removed interface. The address calculation for the position of the data which comes after the removed interface assumed that the bat_iv.bcast_own is a pointer to a single byte datatype. But it is a pointer to unsigned long and thus the calculated position was wrong off factor sizeof(unsigned long). Fixes: 83a8342678a0 ("more basic routing code added (forwarding packets / bitarray added)") Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/bat_iv_ogm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 912d9c36fb1c..aa94b4ec766a 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -185,7 +185,8 @@ unlock: static int batadv_iv_ogm_orig_del_if(struct batadv_orig_node *orig_node, int max_if_num, int del_if_num) { - int chunk_size, ret = -ENOMEM, if_offset; + int ret = -ENOMEM; + size_t chunk_size, if_offset; void *data_ptr = NULL; spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock); @@ -203,8 +204,9 @@ static int batadv_iv_ogm_orig_del_if(struct batadv_orig_node *orig_node, memcpy(data_ptr, orig_node->bat_iv.bcast_own, del_if_num * chunk_size); /* copy second part */ + if_offset = (del_if_num + 1) * chunk_size; memcpy((char *)data_ptr + del_if_num * chunk_size, - orig_node->bat_iv.bcast_own + ((del_if_num + 1) * chunk_size), + (uint8_t *)orig_node->bat_iv.bcast_own + if_offset, (max_if_num - del_if_num) * chunk_size); free_bcast_own: -- 2.20.1