Commit 34b1e0e9 authored Dec 15, 2018 by Sara Sharon Committed by Johannes Berg Dec 19, 2018

mac80211: free skb fraglist before freeing the skb



mac80211 uses the frag list to build AMSDU. When freeing
the skb, it may not be really freed, since someone is still
holding a reference to it.
In that case, when TCP skb is being retransmitted, the
pointer to the frag list is being reused, while the data
in there is no longer valid.
Since we will never get frag list from the network stack,
as mac80211 doesn't advertise the capability, we can safely
free and nullify it before releasing the SKB.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

parent d350a0f4

net/mac80211/status.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -556,6 +556,11 @@ static void ieee80211_report_used_skb(struct ieee80211_local *local,
		}

		ieee80211_led_tx(local);

		if (skb_has_frag_list(skb)) {
		kfree_skb_list(skb_shinfo(skb)->frag_list);
		skb_shinfo(skb)->frag_list = NULL;
		}
		}

		/*

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