diff options
| author |   Gustavo A. R. Silva <garsilva@embeddedor.com> | 2018-03-07 20:27:56 -0600 |
|---|---|---|
| committer |   Alexandre Belloni <alexandre.belloni@bootlin.com> | 2018-03-17 14:20:56 +0100 |
| commit | fed9b18611f75110d5b26d650819665d528038da (patch) | |
| tree | bca711325de4c186d2e3d42320211fc758b828e8 /drivers/rtc/rtc-bq32k.c | |
| parent | rtc: Add useful timestamp definitions (diff) | |
| download | linux-dev-fed9b18611f75110d5b26d650819665d528038da.tar.xz linux-dev-fed9b18611f75110d5b26d650819665d528038da.zip | |
rtc: remove VLA usage
In preparation to enabling -Wvla, remove VLA and replace it
with a fixed-length array 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 <garsilva@embeddedor.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc/rtc-bq32k.c')
| -rw-r--r-- | drivers/rtc/rtc-bq32k.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/rtc/rtc-bq32k.c b/drivers/rtc/rtc-bq32k.c index e8698e9870fe..ef52741000a8 100644 --- a/drivers/rtc/rtc-bq32k.c +++ b/drivers/rtc/rtc-bq32k.c @@ -36,6 +36,10 @@ #define BQ32K_CFG2 0x09 /* Trickle charger control */ #define BQ32K_TCFE BIT(6) /* Trickle charge FET bypass */ +#define MAX_LEN 10 /* Maximum number of consecutive + * register for this particular RTC. + */ + struct bq32k_regs { uint8_t seconds; uint8_t minutes; @@ -74,7 +78,7 @@ static int bq32k_read(struct device *dev, void *data, uint8_t off, uint8_t len) static int bq32k_write(struct device *dev, void *data, uint8_t off, uint8_t len) { struct i2c_client *client = to_i2c_client(dev); - uint8_t buffer[len + 1]; + uint8_t buffer[MAX_LEN + 1]; buffer[0] = off; memcpy(&buffer[1], data, len); |