[RESEND PATCH v5 5/6] Bluetooth: switch to lock_sock in RFCOMM

Desmond Cheong Zhi Xi desmondcheongzx at gmail.com
Wed Aug 4 15:47:11 UTC 2021


Other than rfcomm_sk_state_change and rfcomm_connect_ind, functions in
RFCOMM use lock_sock to lock the socket.

Since bh_lock_sock and spin_lock_bh do not provide synchronization
with lock_sock, these calls should be changed to lock_sock.

This is now safe to do because packet processing is now done in a
workqueue instead of a tasklet, so bh_lock_sock/spin_lock_bh are no
longer necessary to synchronise between user contexts and SOFTIRQ
processing.

Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx at gmail.com>
---
 net/bluetooth/rfcomm/sock.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index ae6f80730561..2c95bb58f901 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -70,7 +70,7 @@ static void rfcomm_sk_state_change(struct rfcomm_dlc *d, int err)
 
 	BT_DBG("dlc %p state %ld err %d", d, d->state, err);
 
-	spin_lock_bh(&sk->sk_lock.slock);
+	lock_sock(sk);
 
 	if (err)
 		sk->sk_err = err;
@@ -91,7 +91,7 @@ static void rfcomm_sk_state_change(struct rfcomm_dlc *d, int err)
 		sk->sk_state_change(sk);
 	}
 
-	spin_unlock_bh(&sk->sk_lock.slock);
+	release_sock(sk);
 
 	if (parent && sock_flag(sk, SOCK_ZAPPED)) {
 		/* We have to drop DLC lock here, otherwise
@@ -974,7 +974,7 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc *
 	if (!parent)
 		return 0;
 
-	bh_lock_sock(parent);
+	lock_sock(parent);
 
 	/* Check for backlog size */
 	if (sk_acceptq_is_full(parent)) {
@@ -1001,7 +1001,7 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc *
 	result = 1;
 
 done:
-	bh_unlock_sock(parent);
+	release_sock(parent);
 
 	if (test_bit(BT_SK_DEFER_SETUP, &bt_sk(parent)->flags))
 		parent->sk_state_change(parent);
-- 
2.25.1



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