[syzbot] [bluetooth?] KASAN: slab-use-after-free Read in __lock_sock

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Subject: [bluetooth?] KASAN: slab-use-after-free Read in __lock_sock
Author: eadavis@qq.com

please test uaf in __lock_sock

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git 8de1e7afcc1c

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index c736186aba26..692727831dde 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -443,6 +443,7 @@ static void __sco_sock_close(struct sock *sk)
 			sco_conn_lock(sco_pi(sk)->conn);
 			hci_conn_drop(sco_pi(sk)->conn->hcon);
 			sco_pi(sk)->conn->hcon = NULL;
+			sco_pi(sk)->conn->sk = NULL;
 			sco_conn_unlock(sco_pi(sk)->conn);
 		} else
 			sco_chan_del(sk, ECONNRESET);