Re: [PATCH v4] cachefiles: fix error return code in cachefiles_ondemand_copen()

[JeffleXu <jefflexu@linux.alibaba.com>]

On 8/26/22 10:35 AM, Sun Ke wrote:
> The cache_size field of copen is specified by the user daemon.
> If cache_size < 0, then the OPEN request is expected to fail,
> while copen itself shall succeed. However, returning 0 is indeed
> unexpected when cache_size is an invalid error code.
> 
> Fix this by returning error when cache_size is an invalid error code.
> 
> Fixes: c8383054506c ("cachefiles: notify the user daemon when looking up cookie")
> Signed-off-by: Sun Ke <sunke32@huawei.com>
> Suggested-by: Jeffle Xu <jefflexu@linux.alibaba.com>
> Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>

Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>

Thanks Sun. Also thanks Dan for the suggestion.


Jingbo Xu

> ---
> v4: update the code suggested by Dan
> v3: update the commit log suggested by Jingbo.
>  fs/cachefiles/ondemand.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/cachefiles/ondemand.c b/fs/cachefiles/ondemand.c
> index 1fee702d5529..7e1586bd5cf3 100644
> --- a/fs/cachefiles/ondemand.c
> +++ b/fs/cachefiles/ondemand.c
> @@ -158,9 +158,13 @@ int cachefiles_ondemand_copen(struct cachefiles_cache *cache, char *args)
>  
>  	/* fail OPEN request if daemon reports an error */
>  	if (size < 0) {
> -		if (!IS_ERR_VALUE(size))
> -			size = -EINVAL;
> -		req->error = size;
> +		if (!IS_ERR_VALUE(size)) {
> +			req->error = -EINVAL;
> +			ret = -EINVAL;
> +		} else {
> +			req->error = size;
> +			ret = 0;
> +		}
>  		goto out;
>  	}
>  

-- 
Thanks,
Jingbo