Re: [syzbot] [PATCH wireless v2] wifi: mac80211: drop invalid source address OCB frames

[syzbot <syzbot+8b512026a7ec10dcbdd9@syzkaller.appspotmail.com>]

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***

Subject: [PATCH wireless v2] wifi: mac80211: drop invalid source address OCB frames
Author: johannes@sipsolutions.net

From: Johannes Berg <johannes.berg@intel.com>

In OCB, don't accept frames from invalid source addresses
(and in particular don't try to create stations for them),
drop the frames instead.

Reported-by: syzbot+8b512026a7ec10dcbdd9@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/6788d2d9.050a0220.20d369.0028.GAE@google.com/
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
#syz test
---
 net/mac80211/rx.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 09beb65d6108..e73431549ce7 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -4432,6 +4432,10 @@ static bool ieee80211_accept_frame(struct ieee80211_rx_data *rx)
 		if (!multicast &&
 		    !ether_addr_equal(sdata->dev->dev_addr, hdr->addr1))
 			return false;
+		/* reject invalid/our STA address */
+		if (!is_valid_ether_addr(hdr->addr2) ||
+		    ether_addr_equal(sdata->dev->dev_addr, hdr->addr2))
+			return false;
 		if (!rx->sta) {
 			int rate_idx;
 			if (status->encoding != RX_ENC_LEGACY)
-- 
2.49.0