4.4-stable patches

added patches:
	mac80211-initialize-fast-xmit-info-later.patch

diff --git a/queue-4.4/mac80211-initialize-fast-xmit-info-later.patch b/queue-4.4/mac80211-initialize-fast-xmit-info-later.patch
new file mode 100644 (file)
index 0000000..0237527
--- /dev/null
+++ b/queue-4.4/mac80211-initialize-fast-xmit-info-later.patch
@@ -0,0 +1,46 @@
+From 35f432a03e41d3bf08c51ede917f94e2288fbe8c Mon Sep 17 00:00:00 2001
+From: Johannes Berg <johannes.berg@intel.com>
+Date: Mon, 2 Jan 2017 11:19:29 +0100
+Subject: mac80211: initialize fast-xmit 'info' later
+
+From: Johannes Berg <johannes.berg@intel.com>
+
+commit 35f432a03e41d3bf08c51ede917f94e2288fbe8c upstream.
+
+In ieee80211_xmit_fast(), 'info' is initialized to point to the skb
+that's passed in, but that skb may later be replaced by a clone (if
+it was shared), leading to an invalid pointer.
+
+This can lead to use-after-free and also later crashes since the
+real SKB's info->hw_queue doesn't get initialized properly.
+
+Fix this by assigning info only later, when it's needed, after the
+skb replacement (may have) happened.
+
+Reported-by: Ben Greear <greearb@candelatech.com>
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ net/mac80211/tx.c |    3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+--- a/net/mac80211/tx.c
++++ b/net/mac80211/tx.c
+@@ -2699,7 +2699,7 @@ static bool ieee80211_xmit_fast(struct i
+       int extra_head = fast_tx->hdr_len - (ETH_HLEN - 2);
+       int hw_headroom = sdata->local->hw.extra_tx_headroom;
+       struct ethhdr eth;
+-      struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
++      struct ieee80211_tx_info *info;
+       struct ieee80211_hdr *hdr = (void *)fast_tx->hdr;
+       struct ieee80211_tx_data tx;
+       ieee80211_tx_result r;
+@@ -2761,6 +2761,7 @@ static bool ieee80211_xmit_fast(struct i
+       memcpy(skb->data + fast_tx->da_offs, eth.h_dest, ETH_ALEN);
+       memcpy(skb->data + fast_tx->sa_offs, eth.h_source, ETH_ALEN);
+ 
++      info = IEEE80211_SKB_CB(skb);
+       memset(info, 0, sizeof(*info));
+       info->band = fast_tx->band;
+       info->control.vif = &sdata->vif;

diff --git a/queue-4.4/series b/queue-4.4/series
index 88a7a45df8ec97d446246256c76b2c5bddbe45f4..37211ad4a8d0af0c5888cb6048acbfdbaed412b1 100644 (file)
--- a/queue-4.4/series
+++ b/queue-4.4/series
@@ -2,3 +2,4 @@ alsa-hda-fix-up-gpio-for-asus-rog-ranger.patch
 alsa-hda-apply-asus-mode8-fixup-to-asus-x71sl.patch
 alsa-usb-audio-fix-irq-process-data-synchronization.patch
 arm-davinci-da850-don-t-add-emac-clock-to-lookup-table-twice.patch
+mac80211-initialize-fast-xmit-info-later.patch