From: Martin Willi Date: Fri, 13 May 2016 10:41:48 +0000 (+0200) Subject: mac80211_hwsim: Add missing check for HWSIM_ATTR_SIGNAL X-Git-Tag: firefly_0821_release~176^2~4^2~37^2~144 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=43e319d7c0ff644ab767c19e7669c9bf5d41a5b2;p=firefly-linux-kernel-4.4.55.git mac80211_hwsim: Add missing check for HWSIM_ATTR_SIGNAL commit 62397da50bb20a6b812c949ef465d7e69fe54bb6 upstream. A wmediumd that does not send this attribute causes a NULL pointer dereference, as the attribute is accessed even if it does not exist. The attribute was required but never checked ever since userspace frame forwarding has been introduced. The issue gets more problematic once we allow wmediumd registration from user namespaces. Fixes: 7882513bacb1 ("mac80211_hwsim driver support userspace frame tx/rx") Signed-off-by: Martin Willi Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c index c00a7daaa4bc..0cd95120bc78 100644 --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -2723,6 +2723,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2, if (!info->attrs[HWSIM_ATTR_ADDR_TRANSMITTER] || !info->attrs[HWSIM_ATTR_FLAGS] || !info->attrs[HWSIM_ATTR_COOKIE] || + !info->attrs[HWSIM_ATTR_SIGNAL] || !info->attrs[HWSIM_ATTR_TX_INFO]) goto out;