staging: vt6656: Use const for read only data

Use const for the arrays that are used as "read only". Also, modify the
prototype of vnt_control_out_blocks() function to use a pointer to a
const type.

The vnt_vt3184_al2230 array can't be converted to const as it's modified
later.

Then in the vnt_vt3184_init() function use two types of pointers (to
const type and to no const type) to avoid the compiler warning:

assignment discards 'const' qualifiers from pointer target type

This way decrease the .data section and increase the .rodata section
limiting the surface attack.

Before this change:
-------------------

drivers/staging/vt6656/baseband.o  :
section              size   addr
.text                1278      0
.data                 576      0
.bss                    0      0
.rodata               319      0
.comment               45      0
.note.GNU-stack         0      0
.note.gnu.property     32      0
Total                2250

After this change:
------------------

drivers/staging/vt6656/baseband.o  :
section              size   addr
.text                1278      0
.data                 256      0
.bss                    0      0
.rodata               640      0
.comment               45      0
.note.GNU-stack         0      0
.note.gnu.property     32      0
Total                2251

Signed-off-by: Oscar Carter <oscar.carter@gmx.com>
Link: https://lore.kernel.org/r/20200504171414.11307-1-oscar.carter@gmx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Oscar Carter 2020-05-04 19:14:14 +02:00 committed by Greg Kroah-Hartman
parent 0729bb9b2a
commit 2e11cc1ab7
3 changed files with 11 additions and 7 deletions

View File

@ -31,7 +31,7 @@
#include "rf.h"
#include "usbpipe.h"
static u8 vnt_vt3184_agc[] = {
static const u8 vnt_vt3184_agc[] = {
0x00, 0x00, 0x02, 0x02, 0x04, 0x04, 0x06, 0x06,
0x08, 0x08, 0x0a, 0x0a, 0x0c, 0x0c, 0x0e, 0x0e, /* 0x0f */
0x10, 0x10, 0x12, 0x12, 0x14, 0x14, 0x16, 0x16,
@ -78,7 +78,7 @@ static u8 vnt_vt3184_al2230[] = {
};
/* {{RobertYu:20060515, new BB setting for VT3226D0 */
static u8 vnt_vt3184_vt3226d0[] = {
static const u8 vnt_vt3184_vt3226d0[] = {
0x31, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x00,
0x70, 0x45, 0x2a, 0x76, 0x00, 0x00, 0x80, 0x00, /* 0x0f */
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@ -243,7 +243,8 @@ int vnt_vt3184_init(struct vnt_private *priv)
{
int ret;
u16 length;
u8 *addr;
u8 *addr = NULL;
const u8 *c_addr;
u8 data;
ret = vnt_control_in(priv, MESSAGE_TYPE_READ, 0, MESSAGE_REQUEST_EEPROM,
@ -275,7 +276,7 @@ int vnt_vt3184_init(struct vnt_private *priv)
(priv->rf_type == RF_VT3342A0)) {
priv->bb_rx_conf = vnt_vt3184_vt3226d0[10];
length = sizeof(vnt_vt3184_vt3226d0);
addr = vnt_vt3184_vt3226d0;
c_addr = vnt_vt3184_vt3226d0;
priv->bb_vga[0] = 0x20;
priv->bb_vga[1] = 0x10;
@ -291,8 +292,11 @@ int vnt_vt3184_init(struct vnt_private *priv)
goto end;
}
if (addr)
c_addr = addr;
ret = vnt_control_out_blocks(priv, VNT_REG_BLOCK_SIZE,
MESSAGE_REQUEST_BBREG, length, addr);
MESSAGE_REQUEST_BBREG, length, c_addr);
if (ret)
goto end;

View File

@ -77,7 +77,7 @@ int vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 data)
}
int vnt_control_out_blocks(struct vnt_private *priv,
u16 block, u8 reg, u16 length, u8 *data)
u16 block, u8 reg, u16 length, const u8 *data)
{
int ret = 0, i;

View File

@ -52,7 +52,7 @@ int vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 ref_off, u8 data);
int vnt_control_in_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 *data);
int vnt_control_out_blocks(struct vnt_private *priv,
u16 block, u8 reg, u16 len, u8 *data);
u16 block, u8 reg, u16 len, const u8 *data);
int vnt_start_interrupt_urb(struct vnt_private *priv);
int vnt_submit_rx_urb(struct vnt_private *priv, struct vnt_rcb *rcb);