[v1] examples/vm_power: fix strcpy buffer overrun

  replace strcpy with rte_strlcpy to prevent buffer overrun
With fix, attempting to use a VERY lonng vm name results in a nicely
truncated 32 character name rather than a segfault:
Setting VM Name to [sdfdsfsfsdffdsdsasdsadasdakjshd]

Cc: stable@dpdk.org
Fixes: 59287933a0bb ("examples/vm_power: add options to guest app")
Signed-off-by: David Hunt <david.hunt@intel.com>
---
 examples/vm_power_manager/guest_cli/main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
  

On 12-Jul-19 3:04 PM, David Hunt wrote:
> replace strcpy with rte_strlcpy to prevent buffer overrun
> With fix, attempting to use a VERY lonng vm name results in a nicely
> truncated 32 character name rather than a segfault:
> Setting VM Name to [sdfdsfsfsdffdsdsasdsadasdakjshd]
> 
> Cc: stable@dpdk.org
> Fixes: 59287933a0bb ("examples/vm_power: add options to guest app")
> Signed-off-by: David Hunt <david.hunt@intel.com>
> ---

Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
  

On Fri, Jul 12, 2019 at 03:04:02PM +0100, David Hunt wrote:
> replace strcpy with rte_strlcpy to prevent buffer overrun
> With fix, attempting to use a VERY lonng vm name results in a nicely
> truncated 32 character name rather than a segfault:
> Setting VM Name to [sdfdsfsfsdffdsdsasdsadasdakjshd]
> 
> Cc: stable@dpdk.org
> Fixes: 59287933a0bb ("examples/vm_power: add options to guest app")
> Signed-off-by: David Hunt <david.hunt@intel.com>
> ---
>  examples/vm_power_manager/guest_cli/main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/examples/vm_power_manager/guest_cli/main.c b/examples/vm_power_manager/guest_cli/main.c
> index 36365b124..a18eb214a 100644
> --- a/examples/vm_power_manager/guest_cli/main.c
> +++ b/examples/vm_power_manager/guest_cli/main.c
> @@ -65,7 +65,7 @@ parse_args(int argc, char **argv)
>  		switch (opt) {
>  		/* portmask */
>  		case 'n':
> -			strcpy(policy->vm_name, optarg);
> +			rte_strlcpy(policy->vm_name, optarg, VM_MAX_NAME_SZ);
>  			printf("Setting VM Name to [%s]\n", policy->vm_name);
>  			break;
>  		case 'b':
> -- 

You can just use "strlcpy" without the "rte_" prefix. The rte_ version is
just a fallback used when a standard strlcpy - either natively or from
libbsd - is unavailable.
  

12/07/2019 16:47, Bruce Richardson:
> On Fri, Jul 12, 2019 at 03:04:02PM +0100, David Hunt wrote:
> > replace strcpy with rte_strlcpy to prevent buffer overrun
> > With fix, attempting to use a VERY lonng vm name results in a nicely
> > truncated 32 character name rather than a segfault:
> > Setting VM Name to [sdfdsfsfsdffdsdsasdsadasdakjshd]
> > 
> > Cc: stable@dpdk.org
> > Fixes: 59287933a0bb ("examples/vm_power: add options to guest app")
> > Signed-off-by: David Hunt <david.hunt@intel.com>

It should be in this order:

Fixes: 59287933a0bb ("examples/vm_power: add options to guest app")
Cc: stable@dpdk.org

Signed-off-by: David Hunt <david.hunt@intel.com>

When in doubt about formatting, please check the git history.
You will find that the recent title prefix in use was "examples/power".

> > --- a/examples/vm_power_manager/guest_cli/main.c
> > +++ b/examples/vm_power_manager/guest_cli/main.c
> > -			strcpy(policy->vm_name, optarg);
> > +			rte_strlcpy(policy->vm_name, optarg, VM_MAX_NAME_SZ);
> 
> You can just use "strlcpy" without the "rte_" prefix. The rte_ version is
> just a fallback used when a standard strlcpy - either natively or from
> libbsd - is unavailable.

Please replace the 2 other occurences of rte_strlcpy in this example
(can be in the same patch with a small comment in the commit log).