Re: [PATCH] twl-core: fix oops while calling twl_i2c_* for unbound driver

[Ilya Yanok <yanok@emcraft.com>]

Hi,

this is still unfixed. twl_i2c_{read,write} are exported and can be 
called before driver initialization so we have to check it before 
dereferencing twl_map.

Regards, Ilya.

02.08.2011 1:00, Ilya Yanok wrote:
> Check inuse variable before trying to access twl_map to prevent
> dereferencing of uninitialized variable.
>
> Signed-off-by: Ilya Yanok<yanok@emcraft.com>
> ---
>   drivers/mfd/twl-core.c |   16 ++++++++--------
>   1 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
> index 01ecfee..c7bc222 100644
> --- a/drivers/mfd/twl-core.c
> +++ b/drivers/mfd/twl-core.c
> @@ -362,13 +362,13 @@ int twl_i2c_write(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
>   		pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
>   		return -EPERM;
>   	}
> -	sid = twl_map[mod_no].sid;
> -	twl =&twl_modules[sid];
> -
>   	if (unlikely(!inuse)) {
> -		pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
> +		pr_err("%s: not initialized\n", DRIVER_NAME);
>   		return -EPERM;
>   	}
> +	sid = twl_map[mod_no].sid;
> +	twl =&twl_modules[sid];
> +
>   	mutex_lock(&twl->xfer_lock);
>   	/*
>   	 * [MSG1]: fill the register address data
> @@ -419,13 +419,13 @@ int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
>   		pr_err("%s: invalid module number %d\n", DRIVER_NAME, mod_no);
>   		return -EPERM;
>   	}
> -	sid = twl_map[mod_no].sid;
> -	twl =&twl_modules[sid];
> -
>   	if (unlikely(!inuse)) {
> -		pr_err("%s: client %d is not initialized\n", DRIVER_NAME, sid);
> +		pr_err("%s: not initialized\n", DRIVER_NAME);
>   		return -EPERM;
>   	}
> +	sid = twl_map[mod_no].sid;
> +	twl =&twl_modules[sid];
> +
>   	mutex_lock(&twl->xfer_lock);
>   	/* [MSG1] fill the register address data */
>   	msg =&twl->xfer_msg[0];