From: Lin Ma
stable inclusion
from linux-4.19.194
commit 64700748e8a7af4883538c72ada57999d9a78e92
category: bugfix
issue: #I421EH
CVE: CVE-2021-3564
--------------------------------
commit 6a137caec23aeb9e036cdfd8a46dd8a366460e5d upstream.
In the cleanup routine for failed initialization of HCI device,
the flush_work(&hdev->rx_work) need to be finished before the
flush_work(&hdev->cmd_work). Otherwise, the hci_rx_work() can
possibly invoke new cmd_work and cause a bug, like double free,
in late processings.
This was assigned CVE-2021-3564.
This patch reorder the flush_work() to fix this bug.
Cc: Marcel Holtmann
Cc: Johan Hedberg
Cc: Luiz Augusto von Dentz
Cc: "David S. Miller"
Cc: Jakub Kicinski
Cc: linux-bluetooth@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Lin Ma
Signed-off-by: Hao Xiong
Cc: stable
Signed-off-by: Marcel Holtmann
Signed-off-by: Greg Kroah-Hartman
Signed-off-by: Yang Yingliang
Signed-off-by: Yu Changchun
---
net/bluetooth/hci_core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index e03faca84..fb47fe995 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1496,8 +1496,13 @@ static int hci_dev_do_open(struct hci_dev *hdev)
} else {
/* Init failed, cleanup */
flush_work(&hdev->tx_work);
- flush_work(&hdev->cmd_work);
+
+ /* Since hci_rx_work() is possible to awake new cmd_work
+ * it should be flushed first to avoid unexpected call of
+ * hci_cmd_work()
+ */
flush_work(&hdev->rx_work);
+ flush_work(&hdev->cmd_work);
skb_queue_purge(&hdev->cmd_q);
skb_queue_purge(&hdev->rx_q);
--
2.25.1
