rtc: s5m: Remove VLA usage

In preparation to enabling -Wvla, remove VLAs and replace them
with fixed-length arrays instead.

>From a security viewpoint, the use of Variable Length Arrays can be
a vector for stack overflow attacks. Also, in general, as the code
evolves it is easy to lose track of how big a VLA can get. Thus, we
can end up having segfaults that are hard to debug.

Also, fixed as part of the directive to remove all VLAs from
the kernel: https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Gustavo A. R. Silva 2018-03-10 00:27:35 -06:00 committed by Alexandre Belloni
parent 4a681243cc
commit 756d5282bf

View File

@ -47,6 +47,8 @@ enum {
RTC_MONTH,
RTC_YEAR1,
RTC_YEAR2,
/* Make sure this is always the last enum name. */
RTC_MAX_NUM_TIME_REGS
};
/*
@ -378,7 +380,7 @@ static void s5m8763_tm_to_data(struct rtc_time *tm, u8 *data)
static int s5m_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
struct s5m_rtc_info *info = dev_get_drvdata(dev);
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
int ret;
if (info->regs->read_time_udr_mask) {
@ -424,7 +426,7 @@ static int s5m_rtc_read_time(struct device *dev, struct rtc_time *tm)
static int s5m_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
struct s5m_rtc_info *info = dev_get_drvdata(dev);
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
int ret = 0;
switch (info->device_type) {
@ -461,7 +463,7 @@ static int s5m_rtc_set_time(struct device *dev, struct rtc_time *tm)
static int s5m_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct s5m_rtc_info *info = dev_get_drvdata(dev);
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
unsigned int val;
int ret, i;
@ -511,7 +513,7 @@ static int s5m_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
static int s5m_rtc_stop_alarm(struct s5m_rtc_info *info)
{
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
int ret, i;
struct rtc_time tm;
@ -556,7 +558,7 @@ static int s5m_rtc_stop_alarm(struct s5m_rtc_info *info)
static int s5m_rtc_start_alarm(struct s5m_rtc_info *info)
{
int ret;
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
u8 alarm0_conf;
struct rtc_time tm;
@ -609,7 +611,7 @@ static int s5m_rtc_start_alarm(struct s5m_rtc_info *info)
static int s5m_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct s5m_rtc_info *info = dev_get_drvdata(dev);
u8 data[info->regs->regs_count];
u8 data[RTC_MAX_NUM_TIME_REGS];
int ret;
switch (info->device_type) {