misc: ti_fpc202: Fix off by one in probe()

[PATCH next] misc: ti_fpc202: Fix off by one in probe()

Posted by Dan Carpenter 7 months, 4 weeks ago

The "port_id" is used as an array index into the struct fpc202_priv
priv->addr_caches[] array in fpc202_write_dev_addr().  It's a 2 by 2
array so if "port_id" is FPC202_NUM_PORTS (2) then it's one element
out of bounds.  Change the > to >= to fix this bug.

Fixes: 1e5c9b1efa1c ("misc: add FPC202 dual port controller driver")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/misc/ti_fpc202.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/ti_fpc202.c b/drivers/misc/ti_fpc202.c
index b9c9ee4bfc4e..4e1871870769 100644
--- a/drivers/misc/ti_fpc202.c
+++ b/drivers/misc/ti_fpc202.c
@@ -370,7 +370,7 @@ static int fpc202_probe(struct i2c_client *client)
 			goto unregister_chans;
 		}
 
-		if (port_id > FPC202_NUM_PORTS) {
+		if (port_id >= FPC202_NUM_PORTS) {
 			dev_err(dev, "port ID %d is out of range!\n", port_id);
 			ret = -EINVAL;
 			goto unregister_chans;
-- 
2.47.2

Re: [PATCH next] misc: ti_fpc202: Fix off by one in probe()

Posted by Andi Shyti 7 months, 3 weeks ago

Hi Dan,

On Wed, Apr 23, 2025 at 11:22:30AM +0300, Dan Carpenter wrote:
> The "port_id" is used as an array index into the struct fpc202_priv
> priv->addr_caches[] array in fpc202_write_dev_addr().  It's a 2 by 2
> array so if "port_id" is FPC202_NUM_PORTS (2) then it's one element
> out of bounds.  Change the > to >= to fix this bug.
> 
> Fixes: 1e5c9b1efa1c ("misc: add FPC202 dual port controller driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>

Reviewed-by: Andi Shyti <andi.shyti@kernel.org>

Thanks,
Andi

Re: [PATCH next] misc: ti_fpc202: Fix off by one in probe()

Posted by Romain Gantois 7 months, 4 weeks ago

On Wednesday, 23 April 2025 10:22:30 CEST Dan Carpenter wrote:
> The "port_id" is used as an array index into the struct fpc202_priv
> priv->addr_caches[] array in fpc202_write_dev_addr().  It's a 2 by 2
> array so if "port_id" is FPC202_NUM_PORTS (2) then it's one element
> out of bounds.  Change the > to >= to fix this bug.
> 
> Fixes: 1e5c9b1efa1c ("misc: add FPC202 dual port controller driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
>  drivers/misc/ti_fpc202.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/misc/ti_fpc202.c b/drivers/misc/ti_fpc202.c
> index b9c9ee4bfc4e..4e1871870769 100644
> --- a/drivers/misc/ti_fpc202.c
> +++ b/drivers/misc/ti_fpc202.c
> @@ -370,7 +370,7 @@ static int fpc202_probe(struct i2c_client *client)
>  			goto unregister_chans;
>  		}
> 
> -		if (port_id > FPC202_NUM_PORTS) {
> +		if (port_id >= FPC202_NUM_PORTS) {
>  			dev_err(dev, "port ID %d is out of range!\n", port_id);
>  			ret = -EINVAL;
>  			goto unregister_chans;

Reviewed-by: Romain Gantois <romain.gantois@bootlin.com>

Re: [PATCH next] misc: ti_fpc202: Fix off by one in probe()

Posted by Arnd Bergmann 7 months, 4 weeks ago

On Wed, Apr 23, 2025, at 10:22, Dan Carpenter wrote:
> The "port_id" is used as an array index into the struct fpc202_priv
> priv->addr_caches[] array in fpc202_write_dev_addr().  It's a 2 by 2
> array so if "port_id" is FPC202_NUM_PORTS (2) then it's one element
> out of bounds.  Change the > to >= to fix this bug.
>
> Fixes: 1e5c9b1efa1c ("misc: add FPC202 dual port controller driver")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---

Acked-by: Arnd Bergmann <arnd@arndb.de>