[PATCH 4.9 135/177] Bluetooth: btqcomsmd: Fix skb double free corruption

From: Greg Kroah-Hartman
Date: Fri Mar 23 2018 - 06:10:31 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Loic Poulain <loic.poulain@xxxxxxxxxx>


[ Upstream commit 67b8fbead4685b36d290a0ef91c6ddffc4920ec9 ]

In case of hci send frame failure, skb is still owned
by the caller (hci_core) and then should not be freed.

This fixes crash on dragonboard-410c when sending SCO
packet. skb is freed by both btqcomsmd and hci_core.

Fixes: 1511cc750c3d ("Bluetooth: Introduce Qualcomm WCNSS SMD based HCI driver")
Signed-off-by: Loic Poulain <loic.poulain@xxxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/bluetooth/btqcomsmd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/bluetooth/btqcomsmd.c
+++ b/drivers/bluetooth/btqcomsmd.c
@@ -85,7 +85,8 @@ static int btqcomsmd_send(struct hci_dev
break;
}

- kfree_skb(skb);
+ if (!ret)
+ kfree_skb(skb);

return ret;
}