diff mbox series

[08/13] media: ar0521: don't overflow when checking PLL values

Message ID 39b23d468eea2714a24a94cb6c20aef5aff492e6.1729074076.git.mchehab+huawei@kernel.org (mailing list archive)
State New
Headers show
Series Media: fix several issues on drivers | expand

Commit Message

Mauro Carvalho Chehab Oct. 16, 2024, 10:22 a.m. UTC
The PLL checks are comparing 64 bit integers with 32 bit
ones. Depending on the values of the variables, this may
underflow.

Fix it ensuring that both sides of the expression are u64.

Fixes: 852b50aeed15 ("media: On Semi AR0521 sensor driver")
Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
 drivers/media/i2c/ar0521.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Sakari Ailus Oct. 16, 2024, 12:57 p.m. UTC | #1
Hi Mauro,

On Wed, Oct 16, 2024 at 12:22:24PM +0200, Mauro Carvalho Chehab wrote:
> The PLL checks are comparing 64 bit integers with 32 bit
> ones. Depending on the values of the variables, this may
> underflow.
> 
> Fix it ensuring that both sides of the expression are u64.
> 
> Fixes: 852b50aeed15 ("media: On Semi AR0521 sensor driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> ---
>  drivers/media/i2c/ar0521.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/i2c/ar0521.c b/drivers/media/i2c/ar0521.c
> index fc27238dd4d3..24873149096c 100644
> --- a/drivers/media/i2c/ar0521.c
> +++ b/drivers/media/i2c/ar0521.c
> @@ -255,10 +255,10 @@ static u32 calc_pll(struct ar0521_dev *sensor, u32 freq, u16 *pre_ptr, u16 *mult
>  			continue; /* Minimum value */
>  		if (new_mult > 254)
>  			break; /* Maximum, larger pre won't work either */
> -		if (sensor->extclk_freq * (u64)new_mult < AR0521_PLL_MIN *
> +		if (sensor->extclk_freq * (u64)new_mult < (u64)AR0521_PLL_MIN *
>  		    new_pre)
>  			continue;
> -		if (sensor->extclk_freq * (u64)new_mult > AR0521_PLL_MAX *
> +		if (sensor->extclk_freq * (u64)new_mult > (u64)AR0521_PLL_MAX *
>  		    new_pre)
>  			break; /* Larger pre won't work either */
>  		new_pll = div64_round_up(sensor->extclk_freq * (u64)new_mult,

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
diff mbox series

Patch

diff --git a/drivers/media/i2c/ar0521.c b/drivers/media/i2c/ar0521.c
index fc27238dd4d3..24873149096c 100644
--- a/drivers/media/i2c/ar0521.c
+++ b/drivers/media/i2c/ar0521.c
@@ -255,10 +255,10 @@  static u32 calc_pll(struct ar0521_dev *sensor, u32 freq, u16 *pre_ptr, u16 *mult
 			continue; /* Minimum value */
 		if (new_mult > 254)
 			break; /* Maximum, larger pre won't work either */
-		if (sensor->extclk_freq * (u64)new_mult < AR0521_PLL_MIN *
+		if (sensor->extclk_freq * (u64)new_mult < (u64)AR0521_PLL_MIN *
 		    new_pre)
 			continue;
-		if (sensor->extclk_freq * (u64)new_mult > AR0521_PLL_MAX *
+		if (sensor->extclk_freq * (u64)new_mult > (u64)AR0521_PLL_MAX *
 		    new_pre)
 			break; /* Larger pre won't work either */
 		new_pll = div64_round_up(sensor->extclk_freq * (u64)new_mult,