lkml.org 
[lkml]   [2014]   [Jun]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH 1/9] i2c: Add pointer dereference protection to i2c_match_id()
Date
On Fri,  6 Jun 2014 16:52:24 +0100, Lee Jones <lee.jones@linaro.org> wrote:
> Here we're providing dereference protection for i2c_match_id(), which
> saves us having to do it each time it's called. We're also stripping
> out the (now) needless checks in i2c_device_match(). This patch paves
> the way for other, similar code trimming.
>
> Acked-by: Grant Likely <grant.likely@linaro.org>
> Signed-off-by: Lee Jones <lee.jones@linaro.org>
> ---
> drivers/i2c/i2c-core.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> index 7c7f4b8..d3802dc 100644
> --- a/drivers/i2c/i2c-core.c
> +++ b/drivers/i2c/i2c-core.c
> @@ -82,6 +82,9 @@ void i2c_transfer_trace_unreg(void)
> static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
> const struct i2c_client *client)
> {
> + if (!(id && client))
> + return NULL;
> +
> while (id->name[0]) {
> if (strcmp(client->name, id->name) == 0)
> return id;
> @@ -95,8 +98,6 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
> struct i2c_client *client = i2c_verify_client(dev);
> struct i2c_driver *driver;
>
> - if (!client)
> - return 0;
>
> /* Attempt an OF style match */
> if (of_driver_match_device(dev, drv))
> @@ -107,9 +108,10 @@ static int i2c_device_match(struct device *dev, struct device_driver *drv)
> return 1;
>
> driver = to_i2c_driver(drv);
> - /* match on an id table if there is one */
> - if (driver->id_table)
> - return i2c_match_id(driver->id_table, client) != NULL;
> +
> + /* Finally an I2C match */
> + if (i2c_match_id(driver->id_table, client))
> + return 1;
>
> return 0;

Nit: the above 4 lines can now simply be:

return (i2c_match_id(driver->id_table, client) != NULL);

g.


\
 
 \ /
  Last update: 2014-06-07 10:01    [W:0.175 / U:0.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site