Staging: bcm: Fix information leak in ioctl: IOCTL_BCM_REGISTER_READ_PRIVATE, IOCTL_BCM_EEPROM_REGISTER_READ

This patch fixes an information leak in ioctl
IOCTL_BCM_REGISTER_READ_PRIVATE and
IOCTL_BCM_EEPROM_REGISTER_READ when determining
the number of bytes to copy to user space.  Function,
usb_control_msg, returns the correct number of
bytes from the hardware.  Instead of using
this value, we were using a value derived from
user space. In this case, this value could be more
than the hardware allocated.  Therefore, this
patch copies the proper number of bytes from
the hardware, and uses this value as the maximum
number of bytes for user space.

Signed-off-by: Kevin McKinney <klmckinney1@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 18 insertions, 15 deletions

diff --git a/drivers/staging/bcm/InterfaceIdleMode.c b/drivers/staging/bcm/InterfaceIdleMode.c
index 96fa4ead7930..faeb03e62c06 100644
--- a/drivers/staging/bcm/InterfaceIdleMode.c
+++ b/drivers/staging/bcm/InterfaceIdleMode.c
@@ -46,6 +46,7 @@ int InterfaceIdleModeRespond(PMINI_ADAPTER Adapter, unsigned int* puiBuffer)
 {
 	int	status = STATUS_SUCCESS;
 	unsigned int	uiRegRead = 0;
+	int bytes;
 
 	BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, IDLE_MODE, DBG_LVL_ALL,"SubType of Message :0x%X", ntohl(*puiBuffer));
 
@@ -77,16 +78,16 @@ int InterfaceIdleModeRespond(PMINI_ADAPTER Adapter, unsigned int* puiBuffer)
 			else if(Adapter->ulPowerSaveMode != DEVICE_POWERSAVE_MODE_AS_PROTOCOL_IDLE_MODE)
 			{
 				//clear on read Register
-				status = rdmalt(Adapter, DEVICE_INT_OUT_EP_REG0, &uiRegRead, sizeof(uiRegRead));
-				if(status)
-				{
+				bytes = rdmalt(Adapter, DEVICE_INT_OUT_EP_REG0, &uiRegRead, sizeof(uiRegRead));
+				if (bytes < 0) {
+					status = bytes;
 					BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "rdm failed while clearing H/W Abort Reg0");
 					return status;
 				}
 				//clear on read Register
-				status = rdmalt (Adapter, DEVICE_INT_OUT_EP_REG1, &uiRegRead, sizeof(uiRegRead));
-				if(status)
-				{
+				bytes = rdmalt(Adapter, DEVICE_INT_OUT_EP_REG1, &uiRegRead, sizeof(uiRegRead));
+				if (bytes < 0) {
+					status = bytes;
 					BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "rdm failed while clearing H/W Abort	Reg1");
 					return status;
 				}
@@ -117,9 +118,9 @@ int InterfaceIdleModeRespond(PMINI_ADAPTER Adapter, unsigned int* puiBuffer)
 					Adapter->chip_id== BCS220_3)
 			{
 
-				status = rdmalt(Adapter, HPM_CONFIG_MSW, &uiRegRead, sizeof(uiRegRead));
-				if(status)
-				{
+				bytes = rdmalt(Adapter, HPM_CONFIG_MSW, &uiRegRead, sizeof(uiRegRead));
+				if (bytes < 0) {
+					status = bytes;
 					BCM_DEBUG_PRINT(Adapter,DBG_TYPE_OTHERS, IDLE_MODE, DBG_LVL_ALL, "rdm failed while Reading HPM_CONFIG_LDO145 Reg 0\n");
 					return status;
 				}
@@ -266,6 +267,8 @@ void InterfaceHandleShutdownModeWakeup(PMINI_ADAPTER Adapter)
 {
 	unsigned int uiRegVal = 0;
 	INT Status = 0;
+	int bytes;
+
 	if(Adapter->ulPowerSaveMode == DEVICE_POWERSAVE_MODE_AS_MANUAL_CLOCK_GATING)
 	{
 		// clear idlemode interrupt.
@@ -282,16 +285,16 @@ void InterfaceHandleShutdownModeWakeup(PMINI_ADAPTER Adapter)
 	{
 
         //clear Interrupt EP registers.
-		Status = rdmalt(Adapter,DEVICE_INT_OUT_EP_REG0, &uiRegVal, sizeof(uiRegVal));
-		if(Status)
-		{
+		bytes = rdmalt(Adapter,DEVICE_INT_OUT_EP_REG0, &uiRegVal, sizeof(uiRegVal));
+		if (bytes < 0) {
+			Status = bytes;
 			BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0,"RDM of DEVICE_INT_OUT_EP_REG0 failed with Err :%d", Status);
 			return;
 		}
 
-        Status = rdmalt(Adapter,DEVICE_INT_OUT_EP_REG1, &uiRegVal, sizeof(uiRegVal));
-		if(Status)
-		{
+		bytes = rdmalt(Adapter,DEVICE_INT_OUT_EP_REG1, &uiRegVal, sizeof(uiRegVal));
+		if (bytes < 0) {
+			Status = bytes;
 			BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0,"RDM of DEVICE_INT_OUT_EP_REG1 failed with Err :%d", Status);
 			return;
 		}