Re: [patch iproute2 1/2] tc: action: fix crash caused by incorrect *argv check

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 23 Jul 2019 13:25:37 +0200
Jiri Pirko <jiri@resnulli.us> wrote:

> From: Jiri Pirko <jiri@mellanox.com>
> 
> One cannot depend on *argv being null in case of no arg is left on the
> command line. For example in batch mode, this is not always true. Check
> argc instead to prevent crash.
> 
> Reported-by: Alex Kushnarov <alexanderk@mellanox.com>
> Fixes: fd8b3d2c1b9b ("actions: Add support for user cookies")
> Signed-off-by: Jiri Pirko <jiri@mellanox.com>
> ---
>  tc/m_action.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tc/m_action.c b/tc/m_action.c
> index ab6bc0ad28ff..0f9c3a27795d 100644
> --- a/tc/m_action.c
> +++ b/tc/m_action.c
> @@ -222,7 +222,7 @@ done0:
>  				goto bad_val;
>  			}
>  
> -			if (*argv && strcmp(*argv, "cookie") == 0) {
> +			if (argc && strcmp(*argv, "cookie") == 0) {
>  				size_t slen;
>  
>  				NEXT_ARG();

Ok, but we should also fix batch mode to null last argv