Re: [PATCH] pstore: Tidy up an error check

[Kees Cook]

On Wed, Dec 02, 2020 at 09:45:31AM +0300, Dan Carpenter wrote:
> The crypto_alloc_comp() function never returns NULL, it returns error
> pointers on error.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

I replied to an identical patch yesterday, actually:
https://lore.kernel.org/lkml/202012011215.B9BF24A6D@keescook/

Using IS_ERR_OR_NULL() is more robust, and this isn't fast path, so I'd
prefer to keep it that way.

-Kees

> ---
>  fs/pstore/platform.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
> index 36714df37d5d..b7a2a2a31dee 100644
> --- a/fs/pstore/platform.c
> +++ b/fs/pstore/platform.c
> @@ -315,7 +315,7 @@ static void allocate_buf_for_compression(void)
>  	}
>  
>  	ctx = crypto_alloc_comp(zbackend->name, 0, 0);
> -	if (IS_ERR_OR_NULL(ctx)) {
> +	if (IS_ERR(ctx)) {
>  		kfree(buf);
>  		pr_err("crypto_alloc_comp('%s') failed: %ld\n", zbackend->name,
>  		       PTR_ERR(ctx));
> -- 
> 2.29.2
> 

-- 
Kees Cook