[dpdk-dev] [PATCH] net/tap: fix coverity warning on strncpy

[Bruce Richardson]

On Fri, Feb 17, 2017 at 08:44:26AM -0600, Keith Wiles wrote:
> Calling strncpy with a maximum size argument of 16 bytes on destination
> array "ifr.ifr_ifrn.ifrn_name" of size 16 bytes might leave the
> destination string unterminated.
> 
> Signed-off-by: Keith Wiles <keith.wiles at intel.com>
> ---
>  drivers/net/tap/rte_eth_tap.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index efc4426..f9938d7 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -297,7 +297,7 @@ tap_link_set_flags(struct pmd_internals *pmd, short flags, int add)
>  		return -1;
>  	}
>  	memset(&ifr, 0, sizeof(ifr));
> -	strncpy(ifr.ifr_name, pmd->name, IFNAMSIZ);
> +	strncpy(ifr.ifr_name, pmd->name, IFNAMSIZ-1);
This is why I always prefer to use snprintf for copying strings, you
can't avoid null terminating.

	snprintf(ifr.ifr_name, IFNAMSIZ, "%s", pmd->name);

	/Bruce