net/softnic: fix memory leak in parsing arguments

  From: Dapeng Yu <dapengx.yu@intel.com>

In function pmd_parse_args(), firmware path is duplicated from device
arguments as character string, but is never freed, which cause memory
leak.

This patch changes the type of firmware member of struct pmd_params to
character array, to make memory resource release unnecessary, and
changes the type of name member to character array, to keep the
consistency of character string handling in struct pmd_params.

Fixes: 7e68bc20f8c8 ("net/softnic: restructure")
Cc: stable@dpdk.org

Signed-off-by: Dapeng Yu <dapengx.yu@intel.com>
---
 drivers/net/softnic/rte_eth_softnic.c           | 9 ++++++---
 drivers/net/softnic/rte_eth_softnic_internals.h | 4 ++--
 2 files changed, 8 insertions(+), 5 deletions(-)
  

@Jasvinder, @Cristian, could you the patch, please.

On 7/8/21 11:44 AM, dapengx.yu@intel.com wrote:
> From: Dapeng Yu <dapengx.yu@intel.com>
> 
> In function pmd_parse_args(), firmware path is duplicated from device
> arguments as character string, but is never freed, which cause memory
> leak.
> 
> This patch changes the type of firmware member of struct pmd_params to
> character array, to make memory resource release unnecessary, and
> changes the type of name member to character array, to keep the
> consistency of character string handling in struct pmd_params.
> 
> Fixes: 7e68bc20f8c8 ("net/softnic: restructure")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Dapeng Yu <dapengx.yu@intel.com>
> ---
>  drivers/net/softnic/rte_eth_softnic.c           | 9 ++++++---
>  drivers/net/softnic/rte_eth_softnic_internals.h | 4 ++--
>  2 files changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/softnic/rte_eth_softnic.c b/drivers/net/softnic/rte_eth_softnic.c
> index f64023256d..4d2f93e9c6 100644
> --- a/drivers/net/softnic/rte_eth_softnic.c
> +++ b/drivers/net/softnic/rte_eth_softnic.c
> @@ -440,6 +440,7 @@ pmd_parse_args(struct pmd_params *p, const char *params)
>  {
>  	struct rte_kvargs *kvlist;
>  	int ret = 0;
> +	char *firmware = NULL;
>  
>  	kvlist = rte_kvargs_parse(params, pmd_valid_args);
>  	if (kvlist == NULL)
> @@ -447,7 +448,7 @@ pmd_parse_args(struct pmd_params *p, const char *params)
>  
>  	/* Set default values */
>  	memset(p, 0, sizeof(*p));
> -	p->firmware = SOFTNIC_FIRMWARE;
> +	snprintf(p->firmware, sizeof(p->firmware), "%s", SOFTNIC_FIRMWARE);

Looking at strlcpy(), rte_strlcpy() and rte_strscpy() I think
that rte_strscpy() is the best option here since it is easier
to check return value to protect against buffer overflow and
shortened result.

>  	p->cpu_id = SOFTNIC_CPU_ID;
>  	p->sc = SOFTNIC_SC;
>  	p->tm.n_queues = SOFTNIC_TM_N_QUEUES;
> @@ -468,10 +469,12 @@ pmd_parse_args(struct pmd_params *p, const char *params)
>  	/* Firmware script (optional) */
>  	if (rte_kvargs_count(kvlist, PMD_PARAM_FIRMWARE) == 1) {
>  		ret = rte_kvargs_process(kvlist, PMD_PARAM_FIRMWARE,
> -			&get_string, &p->firmware);
> +			&get_string, &firmware);
>  		if (ret < 0)
>  			goto out_free;
>  	}
> +	snprintf(p->firmware, sizeof(p->firmware), "%s", firmware);

Same here.

> +	free(firmware);
>  
>  	/* Connection listening port (optional) */
>  	if (rte_kvargs_count(kvlist, PMD_PARAM_CONN_PORT) == 1) {
> @@ -621,7 +624,7 @@ pmd_probe(struct rte_vdev_device *vdev)
>  	if (status)
>  		return status;
>  
> -	p.name = name;
> +	snprintf(p.name, sizeof(p.name), "%s", name);

Same here.

>  
>  	/* Allocate and initialize soft ethdev private data */
>  	dev_private = pmd_init(&p);
> diff --git a/drivers/net/softnic/rte_eth_softnic_internals.h b/drivers/net/softnic/rte_eth_softnic_internals.h
> index 1b3186ef0b..a13d67b7c1 100644
> --- a/drivers/net/softnic/rte_eth_softnic_internals.h
> +++ b/drivers/net/softnic/rte_eth_softnic_internals.h
> @@ -34,8 +34,8 @@
>   */
>  
>  struct pmd_params {
> -	const char *name;
> -	const char *firmware;
> +	char name[RTE_DEV_NAME_MAX_LEN];
> +	char firmware[PATH_MAX];
>  	uint16_t conn_port;
>  	uint32_t cpu_id;
>  	int sc; /**< Service cores. */
>