[PATCH v2] staging: gdm724x: Fix DMA from stack

From: Amey Narkhede
Date: Wed Feb 10 2021 - 03:03:06 EST


Stack allocated buffers cannot be used for DMA
on all architectures so allocate hci_packet buffer
using kzalloc().

Signed-off-by: Amey Narkhede <ameynarkhede03@xxxxxxxxx>
---
Changes in v2:
- Fixed build warning
- Fixed memory leak using kfree

drivers/staging/gdm724x/gdm_usb.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/gdm724x/gdm_usb.c b/drivers/staging/gdm724x/gdm_usb.c
index dc4da66c3..c4a9b90c5 100644
--- a/drivers/staging/gdm724x/gdm_usb.c
+++ b/drivers/staging/gdm724x/gdm_usb.c
@@ -56,11 +56,15 @@ static int gdm_usb_recv(void *priv_dev,

static int request_mac_address(struct lte_udev *udev)
{
- u8 buf[16] = {0,};
- struct hci_packet *hci = (struct hci_packet *)buf;
+ u8 *buf;
+ struct hci_packet *hci;
struct usb_device *usbdev = udev->usbdev;
int actual;
int ret = -1;
+ buf = kzalloc(16, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+ hci = (struct hci_packet *)buf;

hci->cmd_evt = gdm_cpu_to_dev16(udev->gdm_ed, LTE_GET_INFORMATION);
hci->len = gdm_cpu_to_dev16(udev->gdm_ed, 1);
@@ -70,6 +74,7 @@ static int request_mac_address(struct lte_udev *udev)
&actual, 1000);

udev->request_mac_addr = 1;
+ kfree(buf);

return ret;
}
--
2.30.0