From: Lin Ma <redacted>
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 <marcel@holtmann.org>
Cc: Johan Hedberg <redacted>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: <redacted>
Cc: <redacted>
Cc: <redacted>
Signed-off-by: Lin Ma <redacted>
Signed-off-by: Hao Xiong <redacted>
Cc: stable <redacted>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/bluetooth/hci_core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1608,8 +1608,13 @@ setup_failed:
} 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);