Forwarded: [PATCH] wifi: mac80211: fix WARN_ON_ONCE in ieee80211_tdls_oper

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Subject: [PATCH] wifi: mac80211: fix WARN_ON_ONCE in ieee80211_tdls_oper
Author: kartikey406@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master


NL80211_TDLS_ENABLE_LINK can be called without completing the TDLS
setup handshake, or after the TDLS_PEER_SETUP_TIMEOUT (15 seconds)
has expired and tdls_peer_del_work has zeroed out the peer address.
In both cases the WARN_ON_ONCE triggers because tdls_peer is either
zero or mismatched with the requested peer.

Replace the WARN_ON_ONCE with a proper check that returns -ENOLINK
to enforce that ENABLE_LINK can only proceed after a successful TDLS
handshake.

Reported-by: syzbot+56b6a844a4ea74487b7b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=56b6a844a4ea74487b7b
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
---
 net/mac80211/tdls.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c
index dbbfe2d6842f..d7d8b2fcc3ee 100644
--- a/net/mac80211/tdls.c
+++ b/net/mac80211/tdls.c
@@ -1457,8 +1457,9 @@ int ieee80211_tdls_oper(struct wiphy *wiphy, struct net_device *dev,
 
 		set_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH);
 
-		WARN_ON_ONCE(is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
-			     !ether_addr_equal(sdata->u.mgd.tdls_peer, peer));
+		if (is_zero_ether_addr(sdata->u.mgd.tdls_peer) ||
+		    !ether_addr_equal(sdata->u.mgd.tdls_peer, peer))
+			return -ENOLINK;
 		break;
 	case NL80211_TDLS_DISABLE_LINK:
 		/*
-- 
2.43.0