thinkpad-acpi: lock down size of hotkey keymap

Use a safer coding style for the hotkey keymap.  This does not fix any
problems, as the current code is correct.  But it might help avoid
mistakes in the future.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index b9430e8..b0b66fb 100644 (file)
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -1911,6 +1911,17 @@ enum {   /* hot key scan codes (derived from ACPI DSDT) */
        TP_ACPI_HOTKEYSCAN_VOLUMEDOWN,
        TP_ACPI_HOTKEYSCAN_MUTE,
        TP_ACPI_HOTKEYSCAN_THINKPAD,
+       TP_ACPI_HOTKEYSCAN_UNK1,
+       TP_ACPI_HOTKEYSCAN_UNK2,
+       TP_ACPI_HOTKEYSCAN_UNK3,
+       TP_ACPI_HOTKEYSCAN_UNK4,
+       TP_ACPI_HOTKEYSCAN_UNK5,
+       TP_ACPI_HOTKEYSCAN_UNK6,
+       TP_ACPI_HOTKEYSCAN_UNK7,
+       TP_ACPI_HOTKEYSCAN_UNK8,
+
+       /* Hotkey keymap size */
+       TPACPI_HOTKEY_MAP_LEN
 };
 
 enum { /* Keys/events available through NVRAM polling */
@@ -3113,7 +3124,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
         * If the above is too much to ask, don't change the keymap.
         * Ask the thinkpad-acpi maintainer to do it, instead.
         */
-       static u16 ibm_keycode_map[] __initdata = {
+       static u16 ibm_keycode_map[TPACPI_HOTKEY_MAP_LEN] __initdata = {
                /* Scan Codes 0x00 to 0x0B: ACPI HKEY FN+F1..F12 */
                KEY_FN_F1,      KEY_FN_F2,      KEY_COFFEE,     KEY_SLEEP,
                KEY_WLAN,       KEY_FN_F6, KEY_SWITCHVIDEOMODE, KEY_FN_F8,
@@ -3147,7 +3158,7 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
                KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
                KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
        };
-       static u16 lenovo_keycode_map[] __initdata = {
+       static u16 lenovo_keycode_map[TPACPI_HOTKEY_MAP_LEN] __initdata = {
                /* Scan Codes 0x00 to 0x0B: ACPI HKEY FN+F1..F12 */
                KEY_FN_F1,      KEY_COFFEE,     KEY_BATTERY,    KEY_SLEEP,
                KEY_WLAN,       KEY_FN_F6, KEY_SWITCHVIDEOMODE, KEY_FN_F8,
@@ -3191,7 +3202,6 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
                KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
        };
 
-#define TPACPI_HOTKEY_MAP_LEN          ARRAY_SIZE(ibm_keycode_map)
 #define TPACPI_HOTKEY_MAP_SIZE         sizeof(ibm_keycode_map)
 #define TPACPI_HOTKEY_MAP_TYPESIZE     sizeof(ibm_keycode_map[0])
 
@@ -3469,7 +3479,8 @@ static bool hotkey_notify_hotkey(const u32 hkey,
        *send_acpi_ev = true;
        *ignore_acpi_ev = false;
 
-       if (scancode > 0 && scancode < 0x21) {
+       /* HKEY event 0x1001 is scancode 0x00 */
+       if (scancode > 0 && scancode <= TPACPI_HOTKEY_MAP_LEN) {
                scancode--;
                if (!(hotkey_source_mask & (1 << scancode))) {
                        tpacpi_input_send_key_masked(scancode);