Commit 81c044fc authored Jan 13, 2020 by Felix Fietkau Committed by Johannes Berg Jan 15, 2020

cfg80211: fix page refcount issue in A-MSDU decap



The fragments attached to a skb can be part of a compound page. In that case,
page_ref_inc will increment the refcount for the wrong page. Fix this by
using get_page instead, which calls page_ref_inc on the compound head and
also checks for overflow.

Fixes: 2b67f944 ("cfg80211: reuse existing page fragments in A-MSDU rx")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200113182107.20461-1-nbd@nbd.name


Signed-off-by: Johannes Berg <johannes.berg@intel.com>

parent 24953de0

net/wireless/util.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -564,7 +564,7 @@ __frame_add_frag(struct sk_buff skb, struct page page,
		struct skb_shared_info *sh = skb_shinfo(skb);
		int page_offset;

		page_ref_inc(page);
		get_page(page);
		page_offset = ptr - page_address(page);
		skb_add_rx_frag(skb, sh->nr_frags, page, page_offset, len, size);
		}

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