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

ameynarkhede03 at gmail.com ameynarkhede03 at gmail.com
Tue Feb 9 19:31:47 UTC 2021


From: Amey Narkhede <ameynarkhede03 at gmail.com>

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

Signed-off-by: Amey Narkhede <ameynarkhede03 at gmail.com>
---
 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


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