[U-Boot] [PATCH 1/2] pwm: imx: Prevent NULL pointer dereference

Stefano Babic
2015-05-23T10:22:22Z

Hi Axel,

On 23/05/2015 09:16, Axel Lin wrote:
> pwm_id_to_reg() can return NULL, so add NULL testing to prevent NULL pointer
> dereference.
>
> Signed-off-by: Axel Lin <axel.lin@ingics.com>
> ---
> drivers/pwm/pwm-imx.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
> index 40bf027..47799fc 100644
> --- a/drivers/pwm/pwm-imx.c
> +++ b/drivers/pwm/pwm-imx.c
> @@ -18,6 +18,9 @@ int pwm_init(int pwm_id, int div, int invert)
> {
> struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> + if (!pwm)
> + return -1;
> +
> writel(0, &pwm->ir);
> return 0;
> }
> @@ -28,6 +31,9 @@ int pwm_config(int pwm_id, int duty_ns, int period_ns)
> unsigned long period_cycles, duty_cycles, prescale;
> u32 cr;
>
> + if (!pwm)
> + return -1;
> +
> pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
> &prescale);
>
> @@ -47,6 +53,9 @@ int pwm_enable(int pwm_id)
> {
> struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> + if (!pwm)
> + return -1;
> +
> setbits_le32(&pwm->cr, PWMCR_EN);
> return 0;
> }
> @@ -55,5 +64,8 @@ void pwm_disable(int pwm_id)
> {
> struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
>
> + if (!pwm)
> + return;
> +
> clrbits_le32(&pwm->cr, PWMCR_EN);
> }
>

Right !

Acked-by: Stefano Babic <sbabic@denx.de>