[PATCH 1/3] rsi: use macro for allocating USB buffer

[PATCH 1/3] rsi: use macro for allocating USB buffer

[Amitkumar Karwar]

From: Amitkumar Karwar <amit.karwar@redpinesignals.com>

4 bytes is fixed size for reading or writing USB register. We
will use a macro instead of hardcoding this.

Fixes: b97e9b94ad75c ("rsi: Add new host interface operations")
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
---
 drivers/net/wireless/rsi/rsi_91x_usb.c | 4 ++--
 drivers/net/wireless/rsi/rsi_usb.h     | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
index 3febf24..99a520a 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb.c
@@ -162,7 +162,7 @@ static int rsi_usb_reg_read(struct usb_device *usbdev,
 	u8 *buf;
 	int status = -ENOMEM;
 
-	buf  = kmalloc(0x04, GFP_KERNEL);
+	buf  = kmalloc(RSI_USB_CTRL_BUF_SIZE, GFP_KERNEL);
 	if (!buf)
 		return status;
 
@@ -204,7 +204,7 @@ static int rsi_usb_reg_write(struct usb_device *usbdev,
 	u8 *usb_reg_buf;
 	int status = -ENOMEM;
 
-	usb_reg_buf  = kmalloc(0x04, GFP_KERNEL);
+	usb_reg_buf  = kmalloc(RSI_USB_CTRL_BUF_SIZE, GFP_KERNEL);
 	if (!usb_reg_buf)
 		return status;
 
diff --git a/drivers/net/wireless/rsi/rsi_usb.h b/drivers/net/wireless/rsi/rsi_usb.h
index 3babf81..891daea 100644
--- a/drivers/net/wireless/rsi/rsi_usb.h
+++ b/drivers/net/wireless/rsi/rsi_usb.h
@@ -37,6 +37,7 @@
 #define BT_EP                        2
 
 #define RSI_USB_BUF_SIZE	     4096
+#define RSI_USB_CTRL_BUF_SIZE	     0x04
 
 struct rsi_91x_usbdev {
 	struct rsi_thread rx_thread;
-- 
2.7.4

[PATCH 2/3] rsi: check length before USB read/write register

[Amitkumar Karwar]

From: Amitkumar Karwar <amit.karwar@redpinesignals.com>

These checks are required. Otherwise we may end up getting
memory corruption if invalid length is passed.

Fixes: b97e9b94ad75c ("rsi: Add new host interface operations")
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
---
 drivers/net/wireless/rsi/rsi_91x_usb.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
index 99a520a..3d33ce9 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb.c
@@ -166,6 +166,9 @@ static int rsi_usb_reg_read(struct usb_device *usbdev,
 	if (!buf)
 		return status;
 
+	if (len > RSI_USB_CTRL_BUF_SIZE)
+		return -EINVAL;
+
 	status = usb_control_msg(usbdev,
 				 usb_rcvctrlpipe(usbdev, 0),
 				 USB_VENDOR_REGISTER_READ,
@@ -208,6 +211,9 @@ static int rsi_usb_reg_write(struct usb_device *usbdev,
 	if (!usb_reg_buf)
 		return status;
 
+	if (len > RSI_USB_CTRL_BUF_SIZE)
+		return -EINVAL;
+
 	usb_reg_buf[0] = (value & 0x00ff);
 	usb_reg_buf[1] = (value & 0xff00) >> 8;
 	usb_reg_buf[2] = 0x0;
-- 
2.7.4

[PATCH 3/3] rsi: fix static checker warning

[Amitkumar Karwar]

From: Amitkumar Karwar <amit.karwar@redpinesignals.com>

u32 pointer is changed to u16 and filled the value. Problem is
solved by using local temporary variable. Below static checker
warning was reported.

drivers/net/wireless/rsi/rsi_91x_usb.c:400 rsi_usb_master_reg_read()
        warn: passing casted pointer 'value' to 'rsi_usb_reg_read()'
32 vs 16.

Fixes: b97e9b94ad75c ("rsi: Add new host interface operations")
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
---
 drivers/net/wireless/rsi/rsi_91x_usb.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/rsi/rsi_91x_usb.c b/drivers/net/wireless/rsi/rsi_91x_usb.c
index 3d33ce9..9097f7e 100644
--- a/drivers/net/wireless/rsi/rsi_91x_usb.c
+++ b/drivers/net/wireless/rsi/rsi_91x_usb.c
@@ -404,8 +404,15 @@ static int rsi_usb_master_reg_read(struct rsi_hw *adapter, u32 reg,
 {
 	struct usb_device *usbdev =
 		((struct rsi_91x_usbdev *)adapter->rsi_dev)->usbdev;
+	u16 temp;
+	int ret;
 
-	return rsi_usb_reg_read(usbdev, reg, (u16 *)value, len);
+	ret = rsi_usb_reg_read(usbdev, reg, &temp, len);
+	if (ret < 0)
+		return ret;
+	*value = temp;
+
+	return 0;
 }
 
 static int rsi_usb_master_reg_write(struct rsi_hw *adapter,
-- 
2.7.4

Re: [1/3] rsi: use macro for allocating USB buffer

[Kalle Valo]

Amitkumar Karwar <amitkarwar@gmail.com> wrote:

> From: Amitkumar Karwar <amit.karwar@redpinesignals.com>
> 
> 4 bytes is fixed size for reading or writing USB register. We
> will use a macro instead of hardcoding this.
> 
> Fixes: b97e9b94ad75c ("rsi: Add new host interface operations")
> Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>

3 patches applied to wireless-drivers-next.git, thanks.

523b724a769b rsi: use macro for allocating USB buffer
59f73e2ae185 rsi: check length before USB read/write register
e6249e15fea2 rsi: fix static checker warning

-- 
https://patchwork.kernel.org/patch/9834829/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches