Re: [dpdk-dev] [PATCH v2] lib/cryptodev: fix driver name comparison

[Akhil Goyal <akhil.goyal@nxp.com>]

On 3/11/2019 11:25 AM, Anoob Joseph wrote:
> The string compare to the length of driver name might give false
> positives when there are drivers with similar names (one being the
> subset of another).
>
> Following is such a naming which could result in false positive.
> 1. crypto_driver
> 2. crypto_driver1
>
> When strncmp with len = strlen("crypto_driver") is done, it could give
> a false positive when compared against "crypto_driver1". For such cases,
> 'strlen + 1' is done, so that the NULL termination also would be
> considered for the comparison.
>
> Fixes: d11b0f30df88 ("cryptodev: introduce API and framework for crypto devices")
>
> Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
> Signed-off-by: Anoob Joseph <anoobj@marvell.com>
> ---
> v2:
> * Using strlen + 1, instead of RTE_CRYPTODEV_NAME_MAX_LEN for the comparison.
> * Strcmp would not cause this issue. Touching only the places which
>    would result in the issue.
>
>   lib/librte_cryptodev/rte_cryptodev.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lib/librte_cryptodev/rte_cryptodev.c b/lib/librte_cryptodev/rte_cryptodev.c
> index 7009735..871d7dd 100644
> --- a/lib/librte_cryptodev/rte_cryptodev.c
> +++ b/lib/librte_cryptodev/rte_cryptodev.c
> @@ -586,7 +586,7 @@ rte_cryptodev_devices_get(const char *driver_name, uint8_t *devices,
>   
>   			cmp = strncmp(devs[i].device->driver->name,
>   					driver_name,
> -					strlen(driver_name));
> +					strlen(driver_name) + 1);
>   
>   			if (cmp == 0)
>   				devices[count++] = devs[i].data->dev_id;
> @@ -1691,7 +1691,7 @@ rte_cryptodev_driver_id_get(const char *name)
>   
>   	TAILQ_FOREACH(driver, &cryptodev_driver_list, next) {
>   		driver_name = driver->driver->name;
> -		if (strncmp(driver_name, name, strlen(driver_name)) == 0)
> +		if (strncmp(driver_name, name, strlen(driver_name) + 1) == 0)
>   			return driver->id;
>   	}
>   	return -1;
Acked-by: Akhil Goyal <akhil.goyal@nxp.com>