[PATCH v2] param: add error check to __dev_add_param()

[Sascha Hauer]

On Thu, Jan 29, 2015 at 11:46:53AM +0900, Masahiro Yamada wrote:
> If the argument, name is given with NULL, it would be probably
> unexpected behavior.  It should fail rather than register the
> NULL-named parameter.
> 
> If strdup() fails with out-of-memory, it should also fail
> with -ENOMEM.
> 
> Signed-off-by: Masahiro Yamada <yamada.m at jp.panasonic.com>
> ---
> 
> Changes in v2:
>   - Fix the condition of returning -ENOMEM
> 
>  lib/parameter.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/parameter.c b/lib/parameter.c
> index 71262c4..02a89bb 100644
> --- a/lib/parameter.c
> +++ b/lib/parameter.c
> @@ -130,6 +130,13 @@ static int __dev_add_param(struct param_d *param, struct device_d *dev, const ch
>  	if (get_param_by_name(dev, name))
>  		return -EEXIST;
>  
> +	if (!name)
> +		return -EINVAL;

Name is used already two lines above so barebox will already be crashed
before this triggers.

Besides, I normally don't like these checks. dereferencing NULL pointers
means you get a backtrace showing you what went wrong. Returning an error
means adding code which in this case makes dev_add_param just fail
silently because the return value often is not checked.

Sascha

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