[SRU OEM-B][PATCH 2/3] UBUNTU: SAUCE: Bluetooth:btrsi: add null check in hci send and recv functions

[Shrirang Bagul]

From: Ganapathi Raju <ganapathi.kondraju at redpinesignals.com>

BugLink: http://bugs.launchpad.net/bugs/1772626

During power save S3 and S4 stress tests driver sometimes crashes
because of accessing the hdev pointer in rsi_hci_recv_pkt() and
rsi_hci_send_pkt() which is NULL. Fixed by adding NULL check
before accessing hdev in these functions.

Signed-off-by: Ganapathi Raju <ganapathi.kondraju at redpinesignals.com>
Signed-off-by: Shrirang Bagul <shrirang.bagul at canonical.com>
---
 drivers/bluetooth/btrsi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/bluetooth/btrsi.c b/drivers/bluetooth/btrsi.c
index 5034325e417c..5dfb2f462f42 100644
--- a/drivers/bluetooth/btrsi.c
+++ b/drivers/bluetooth/btrsi.c
@@ -51,6 +51,9 @@ static int rsi_hci_send_pkt(struct hci_dev *hdev, struct sk_buff *skb)
 	struct rsi_hci_adapter *h_adapter = hci_get_drvdata(hdev);
 	struct sk_buff *new_skb = NULL;
 
+	if (!h_adapter->hdev)
+		return -ENODEV;
+
 	switch (hci_skb_pkt_type(skb)) {
 	case HCI_COMMAND_PKT:
 		hdev->stat.cmd_tx++;
@@ -84,6 +87,9 @@ static int rsi_hci_recv_pkt(void *priv, const u8 *pkt)
 	struct sk_buff *skb;
 	int pkt_len = get_unaligned_le16(pkt) & 0x0fff;
 
+	if (!h_adapter->hdev)
+		return -ENODEV;
+
 	skb = dev_alloc_skb(pkt_len);
 	if (!skb)
 		return -ENOMEM;
-- 
2.17.0