Re: [dpdk-stable] [EXT] [dpdk-dev] [PATCH v2] eal: fix dereference after null check

[Harman Kalra <hkalra@marvell.com>]

On Thu, Oct 15, 2020 at 04:42:30PM +0800, wangyunjian wrote:
> External Email
> 
> ----------------------------------------------------------------------
> From: Yunjian Wang <wangyunjian@huawei.com>
> 
> This patch fixes (dereference after null check) coverity issue.
> For this reason, we should add null check at the beginning of the
> function and return error directly if the 'intr_handle' is null.
> 
> Coverity issue: 357695, 357751
> Fixes: 05c4105738d8 ("trace: add interrupt tracepoints")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>

Thanks for fixing this.

Reviewed-by: Harman Kalra <hkalra@marvell.com>

> ---
> v2:
>   fix code styles suggested by Ferruh Yigit
> ---
>  lib/librte_eal/freebsd/eal_interrupts.c | 16 ++++++++++------
>  lib/librte_eal/linux/eal_interrupts.c   | 16 ++++++++++------
>  2 files changed, 20 insertions(+), 12 deletions(-)
> 
> diff --git a/lib/librte_eal/freebsd/eal_interrupts.c b/lib/librte_eal/freebsd/eal_interrupts.c
> index 6d53d33c8..211fd4f8d 100644
> --- a/lib/librte_eal/freebsd/eal_interrupts.c
> +++ b/lib/librte_eal/freebsd/eal_interrupts.c
> @@ -350,13 +350,15 @@ rte_intr_enable(const struct rte_intr_handle *intr_handle)
>  {
>  	int rc = 0;
>  
> -	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
> +	if (intr_handle == NULL)
> +		return -1;
> +
> +	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
>  		rc = 0;
>  		goto out;
>  	}
>  
> -	if (!intr_handle || intr_handle->fd < 0 ||
> -				intr_handle->uio_cfg_fd < 0) {
> +	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
>  		rc = -1;
>  		goto out;
>  	}
> @@ -389,13 +391,15 @@ rte_intr_disable(const struct rte_intr_handle *intr_handle)
>  {
>  	int rc = 0;
>  
> -	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
> +	if (intr_handle == NULL)
> +		return -1;
> +
> +	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
>  		rc = 0;
>  		goto out;
>  	}
>  
> -	if (!intr_handle || intr_handle->fd < 0 ||
> -				intr_handle->uio_cfg_fd < 0) {
> +	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
>  		rc = -1;
>  		goto out;
>  	}
> diff --git a/lib/librte_eal/linux/eal_interrupts.c b/lib/librte_eal/linux/eal_interrupts.c
> index 13db5c4e8..f1bd0356c 100644
> --- a/lib/librte_eal/linux/eal_interrupts.c
> +++ b/lib/librte_eal/linux/eal_interrupts.c
> @@ -667,13 +667,15 @@ rte_intr_enable(const struct rte_intr_handle *intr_handle)
>  {
>  	int rc = 0;
>  
> -	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
> +	if (intr_handle == NULL)
> +		return -1;
> +
> +	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
>  		rc = 0;
>  		goto out;
>  	}
>  
> -	if (!intr_handle || intr_handle->fd < 0 ||
> -			intr_handle->uio_cfg_fd < 0) {
> +	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
>  		rc = -1;
>  		goto out;
>  	}
> @@ -794,13 +796,15 @@ rte_intr_disable(const struct rte_intr_handle *intr_handle)
>  {
>  	int rc = 0;
>  
> -	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
> +	if (intr_handle == NULL)
> +		return -1;
> +
> +	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
>  		rc = 0;
>  		goto out;
>  	}
>  
> -	if (!intr_handle || intr_handle->fd < 0 ||
> -					intr_handle->uio_cfg_fd < 0) {
> +	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
>  		rc = -1;
>  		goto out;
>  	}
> -- 
> 2.23.0
>