[PATCH 4.4 22/38] cfg80211: remove WARN_ON() in cfg80211_sme_connect - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org,
	syzbot+5f9392825de654244975@syzkaller.appspotmail.com,
	Du Cheng <ducheng2@gmail.com>,
	Johannes Berg <johannes.berg@intel.com>
Subject: [PATCH 4.4 22/38] cfg80211: remove WARN_ON() in cfg80211_sme_connect
Date: Thu, 15 Apr 2021 16:47:16 +0200	[thread overview]
Message-ID: <20210415144414.058015430@linuxfoundation.org> (raw)
In-Reply-To: <20210415144413.352638802@linuxfoundation.org>

From: Du Cheng <ducheng2@gmail.com>

commit 1b5ab825d9acc0f27d2f25c6252f3526832a9626 upstream.

A WARN_ON(wdev->conn) would trigger in cfg80211_sme_connect(), if multiple
send_msg(NL80211_CMD_CONNECT) system calls are made from the userland, which
should be anticipated and handled by the wireless driver. Remove this WARN_ON()
to prevent kernel panic if kernel is configured to "panic_on_warn".

Bug reported by syzbot.

Reported-by: syzbot+5f9392825de654244975@syzkaller.appspotmail.com
Signed-off-by: Du Cheng <ducheng2@gmail.com>
Link: https://lore.kernel.org/r/20210407162756.6101-1-ducheng2@gmail.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/wireless/sme.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -507,7 +507,7 @@ static int cfg80211_sme_connect(struct w
 	if (wdev->current_bss)
 		return -EALREADY;
 
-	if (WARN_ON(wdev->conn))
+	if (wdev->conn)
 		return -EINPROGRESS;
 
 	wdev->conn = kzalloc(sizeof(*wdev->conn), GFP_KERNEL);


