2 files changed, 13 insertions, 2 deletions

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index eb62558e9b09..0c2c93735e93 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -423,8 +423,8 @@ static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
 
                 rfcomm_dlc_lock(d);
                 d->state = BT_CLOSED;
-                rfcomm_dlc_unlock(d);
                 d->state_change(d, err);
+                rfcomm_dlc_unlock(d);
 
                 skb_queue_purge(&d->tx_queue);
                 rfcomm_dlc_unlink(d);
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index c3f749abb2d0..c9191871c1e0 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -566,11 +566,22 @@ static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
         if (dlc->state == BT_CLOSED) {
                 if (!dev->tty) {
                         if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
-                                if (rfcomm_dev_get(dev->id) == NULL)
+                                /* Drop DLC lock here to avoid deadlock
+                                 * 1. rfcomm_dev_get will take rfcomm_dev_lock
+                                 *    but in rfcomm_dev_add there's lock order:
+                                 *    rfcomm_dev_lock -> dlc lock
+                                 * 2. rfcomm_dev_put will deadlock if it's
+                                 *    the last reference
+                                 */
+                                rfcomm_dlc_unlock(dlc);
+                                if (rfcomm_dev_get(dev->id) == NULL) {
+                                        rfcomm_dlc_lock(dlc);
                                         return;
+                                }
 
                                 rfcomm_dev_del(dev);
                                 rfcomm_dev_put(dev);
+                                rfcomm_dlc_lock(dlc);
                         }
                 } else
                         tty_hangup(dev->tty);