[dpdk-dev] [PATCH] net/vdev_netvsc: fix automatic probing

[dpdk-dev] [PATCH] net/vdev_netvsc: fix automatic probing

[Matan Azrad]

The vdev_netvsc driver allows an automatic probe in Hyper-V VM systems
unless it was already specified by the EAL command line.

The detection of a specified NetVSC device is wrongly done by comparing
the vdev_netvsc driver name to all the vdev devices names, including
the suffix device index. Thus, if the user specifies the vdev_netvsc
device by adding an index to the device name, the comparison fails.
Consequently, the vdev_netvsc driver may automatically probe NetVSC
devices, despite the NetVSC device that was specified by the EAL command
line.

Compare the vdev_netvsc driver name to the devices names without the
index.

Fixes: 56252de779a6 ("net/vdev_netvsc: add automatic probing")
Cc: stable@dpdk.org

Signed-off-by: Matan Azrad <matan@mellanox.com>
---
 drivers/net/vdev_netvsc/vdev_netvsc.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c b/drivers/net/vdev_netvsc/vdev_netvsc.c
index de2bd14..48717f2 100644
--- a/drivers/net/vdev_netvsc/vdev_netvsc.c
+++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
@@ -39,6 +39,7 @@
 
 #define VDEV_NETVSC_DRIVER net_vdev_netvsc
 #define VDEV_NETVSC_DRIVER_NAME RTE_STR(VDEV_NETVSC_DRIVER)
+#define VDEV_NETVSC_DRIVER_NAME_LEN 15
 #define VDEV_NETVSC_ARG_IFACE "iface"
 #define VDEV_NETVSC_ARG_MAC "mac"
 #define VDEV_NETVSC_ARG_FORCE "force"
@@ -798,7 +799,8 @@ static LIST_HEAD(, vdev_netvsc_ctx) vdev_netvsc_ctx_list =
 vdev_netvsc_cmp_rte_device(const struct rte_device *dev1,
 			   __rte_unused const void *_dev2)
 {
-	return strcmp(dev1->devargs->name, VDEV_NETVSC_DRIVER_NAME);
+	return strncmp(dev1->devargs->name, VDEV_NETVSC_DRIVER_NAME,
+		       VDEV_NETVSC_DRIVER_NAME_LEN);
 }
 
 /**
@@ -814,7 +816,8 @@ static LIST_HEAD(, vdev_netvsc_ctx) vdev_netvsc_ctx_list =
 	struct rte_bus *vbus = rte_bus_find_by_name("vdev");
 
 	RTE_EAL_DEVARGS_FOREACH("vdev", devargs)
-		if (!strcmp(devargs->name, VDEV_NETVSC_DRIVER_NAME))
+		if (!strncmp(devargs->name, VDEV_NETVSC_DRIVER_NAME,
+			     VDEV_NETVSC_DRIVER_NAME_LEN))
 			return;
 	dev = (struct rte_vdev_device *)vbus->find_device(NULL,
 		vdev_netvsc_cmp_rte_device, VDEV_NETVSC_DRIVER_NAME);
-- 
1.9.5

Re: [dpdk-dev] [PATCH] net/vdev_netvsc: fix automatic probing

[Stephen Hemminger]

On Mon, 21 May 2018 16:23:30 +0000
Matan Azrad <matan@mellanox.com> wrote:

> The vdev_netvsc driver allows an automatic probe in Hyper-V VM systems
> unless it was already specified by the EAL command line.
> 
> The detection of a specified NetVSC device is wrongly done by comparing
> the vdev_netvsc driver name to all the vdev devices names, including
> the suffix device index. Thus, if the user specifies the vdev_netvsc
> device by adding an index to the device name, the comparison fails.
> Consequently, the vdev_netvsc driver may automatically probe NetVSC
> devices, despite the NetVSC device that was specified by the EAL command
> line.
> 
> Compare the vdev_netvsc driver name to the devices names without the
> index.
> 
> Fixes: 56252de779a6 ("net/vdev_netvsc: add automatic probing")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Matan Azrad <matan@mellanox.com>
> ---
>  drivers/net/vdev_netvsc/vdev_netvsc.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c b/drivers/net/vdev_netvsc/vdev_netvsc.c
> index de2bd14..48717f2 100644
> --- a/drivers/net/vdev_netvsc/vdev_netvsc.c
> +++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
> @@ -39,6 +39,7 @@
>  
>  #define VDEV_NETVSC_DRIVER net_vdev_netvsc
>  #define VDEV_NETVSC_DRIVER_NAME RTE_STR(VDEV_NETVSC_DRIVER)
> +#define VDEV_NETVSC_DRIVER_NAME_LEN 15

Looks correct, why did you not just use IFNAMSIZ which is commonly used
across much of the network code?

Re: [dpdk-dev] [PATCH] net/vdev_netvsc: fix automatic probing

[Matan Azrad]

From: Stephen Hemminger
> On Mon, 21 May 2018 16:23:30 +0000
> Matan Azrad <matan@mellanox.com> wrote:
> 
> > The vdev_netvsc driver allows an automatic probe in Hyper-V VM systems
> > unless it was already specified by the EAL command line.
> >
> > The detection of a specified NetVSC device is wrongly done by
> > comparing the vdev_netvsc driver name to all the vdev devices names,
> > including the suffix device index. Thus, if the user specifies the
> > vdev_netvsc device by adding an index to the device name, the comparison
> fails.
> > Consequently, the vdev_netvsc driver may automatically probe NetVSC
> > devices, despite the NetVSC device that was specified by the EAL
> > command line.
> >
> > Compare the vdev_netvsc driver name to the devices names without the
> > index.
> >
> > Fixes: 56252de779a6 ("net/vdev_netvsc: add automatic probing")
> > Cc: stable@dpdk.org
> >
> > Signed-off-by: Matan Azrad <matan@mellanox.com>
> > ---
> >  drivers/net/vdev_netvsc/vdev_netvsc.c | 7 +++++--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c
> > b/drivers/net/vdev_netvsc/vdev_netvsc.c
> > index de2bd14..48717f2 100644
> > --- a/drivers/net/vdev_netvsc/vdev_netvsc.c
> > +++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
> > @@ -39,6 +39,7 @@
> >
> >  #define VDEV_NETVSC_DRIVER net_vdev_netvsc  #define
> > VDEV_NETVSC_DRIVER_NAME RTE_STR(VDEV_NETVSC_DRIVER)
> > +#define VDEV_NETVSC_DRIVER_NAME_LEN 15
> 
> Looks correct, why did you not just use IFNAMSIZ which is commonly used
> across much of the network code?

Actually this is the driver name size (without \0) no an interface name.

Re: [dpdk-dev] [PATCH] net/vdev_netvsc: fix automatic probing

[Ferruh Yigit]

On 5/21/2018 5:23 PM, Matan Azrad wrote:
> The vdev_netvsc driver allows an automatic probe in Hyper-V VM systems
> unless it was already specified by the EAL command line.
> 
> The detection of a specified NetVSC device is wrongly done by comparing
> the vdev_netvsc driver name to all the vdev devices names, including
> the suffix device index. Thus, if the user specifies the vdev_netvsc
> device by adding an index to the device name, the comparison fails.
> Consequently, the vdev_netvsc driver may automatically probe NetVSC
> devices, despite the NetVSC device that was specified by the EAL command
> line.
> 
> Compare the vdev_netvsc driver name to the devices names without the
> index.
> 
> Fixes: 56252de779a6 ("net/vdev_netvsc: add automatic probing")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Matan Azrad <matan@mellanox.com>

Applied to dpdk-next-net/master, thanks.