From 6edb171845edc7bcbed6940002e232ad617822ab Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Sat, 31 May 2025 18:24:58 +0300 Subject: [PATCH] Bluetooth: hci_core: fix list_for_each_entry_rcu usage [ Upstream commit 308a3a8ce8ea41b26c46169f3263e50f5997c28e ] Releasing + re-acquiring RCU lock inside list_for_each_entry_rcu() loop body is not correct. Fix by taking the update-side hdev->lock instead. Fixes: c7eaf80bfb0c ("Bluetooth: Fix hci_link_tx_to RCU lock usage") Signed-off-by: Pauli Virtanen Reviewed-by: Paul Menzel Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/hci_core.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 30519d47e8a6..febfd389ecf4 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3380,23 +3380,18 @@ static void hci_link_tx_to(struct hci_dev *hdev, __u8 type) bt_dev_err(hdev, "link tx timeout"); - rcu_read_lock(); + hci_dev_lock(hdev); /* Kill stalled connections */ - list_for_each_entry_rcu(c, &h->list, list) { + list_for_each_entry(c, &h->list, list) { if (c->type == type && c->sent) { bt_dev_err(hdev, "killing stalled connection %pMR", &c->dst); - /* hci_disconnect might sleep, so, we have to release - * the RCU read lock before calling it. - */ - rcu_read_unlock(); hci_disconnect(c, HCI_ERROR_REMOTE_USER_TERM); - rcu_read_lock(); } } - rcu_read_unlock(); + hci_dev_unlock(hdev); } static struct hci_chan *hci_chan_sent(struct hci_dev *hdev, __u8 type,