From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Tue, 26 May 2015 06:27:22 +0200 Subject: [U-Boot] [PATCH 1/2] pwm: imx: Prevent NULL pointer dereference In-Reply-To: <1432365408.17001.0.camel@ingics.com> References: <1432365408.17001.0.camel@ingics.com> Message-ID: <5563F62A.9010808@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Axel, Am 23.05.2015 09:16, schrieb Axel Lin: > pwm_id_to_reg() can return NULL, so add NULL testing to prevent NULL pointer > dereference. > > Signed-off-by: Axel Lin > --- > drivers/pwm/pwm-imx.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) Acked-by: Heiko Schocher bye, Heiko > > 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); > } > -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany