[PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Harold Huang]

When kni driver calls eth_kni_start to start device, some fields such as
min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
value. This is unexpected and in some time we could not change the kni
device mtu with ip link command.

Fixes: ff1e35fb5f8 ("kni: calculate MTU from mbuf size")
Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
---
 drivers/net/kni/rte_eth_kni.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
index c428caf441..23b15edfac 100644
--- a/drivers/net/kni/rte_eth_kni.c
+++ b/drivers/net/kni/rte_eth_kni.c
@@ -128,6 +128,7 @@ eth_kni_start(struct rte_eth_dev *dev)
 	const char *name = dev->device->name + 4; /* remove net_ */
 
 	mb_pool = internals->rx_queues[0].mb_pool;
+	memset(&conf, 0, sizeof(conf));
 	strlcpy(conf.name, name, RTE_KNI_NAMESIZE);
 	conf.force_bind = 0;
 	conf.group_id = port_id;
-- 
2.27.0

Re: [PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Ferruh Yigit]

On 3/2/2022 12:33 PM, Harold Huang wrote:
> When kni driver calls eth_kni_start to start device, some fields such as
> min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
> kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
> value. This is unexpected and in some time we could not change the kni
> device mtu with ip link command.
> 

Agree on the problem and the solution, thanks for the fix.

> Fixes: ff1e35fb5f8 ("kni: calculate MTU from mbuf size")
> Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
> ---
>   drivers/net/kni/rte_eth_kni.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
> index c428caf441..23b15edfac 100644
> --- a/drivers/net/kni/rte_eth_kni.c
> +++ b/drivers/net/kni/rte_eth_kni.c
> @@ -128,6 +128,7 @@ eth_kni_start(struct rte_eth_dev *dev)
>   	const char *name = dev->device->name + 4; /* remove net_ */
>   
>   	mb_pool = internals->rx_queues[0].mb_pool;
> +	memset(&conf, 0, sizeof(conf));

Can you prefer initialize to zero, instead of 'memset', I think it
is more clear that way:

  -       struct rte_kni_conf conf;
  +       struct rte_kni_conf conf = { 0 };

>   	strlcpy(conf.name, name, RTE_KNI_NAMESIZE);
>   	conf.force_bind = 0;
>   	conf.group_id = port_id;

Re: [PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Harold Huang]

On Thu, Mar 3, 2022 at 2:16 AM Ferruh Yigit <ferruh.yigit@intel.com> wrote:
>
> On 3/2/2022 12:33 PM, Harold Huang wrote:
> > When kni driver calls eth_kni_start to start device, some fields such as
> > min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
> > kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
> > value. This is unexpected and in some time we could not change the kni
> > device mtu with ip link command.
> >
>
> Agree on the problem and the solution, thanks for the fix.
>
> > Fixes: ff1e35fb5f8 ("kni: calculate MTU from mbuf size")
> > Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
> > ---
> >   drivers/net/kni/rte_eth_kni.c | 1 +
> >   1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
> > index c428caf441..23b15edfac 100644
> > --- a/drivers/net/kni/rte_eth_kni.c
> > +++ b/drivers/net/kni/rte_eth_kni.c
> > @@ -128,6 +128,7 @@ eth_kni_start(struct rte_eth_dev *dev)
> >       const char *name = dev->device->name + 4; /* remove net_ */
> >
> >       mb_pool = internals->rx_queues[0].mb_pool;
> > +     memset(&conf, 0, sizeof(conf));
>
> Can you prefer initialize to zero, instead of 'memset', I think it
> is more clear that way:

Thanks. Sounds good,  fix it.

>
>   -       struct rte_kni_conf conf;
>   +       struct rte_kni_conf conf = { 0 };
>
> >       strlcpy(conf.name, name, RTE_KNI_NAMESIZE);
> >       conf.force_bind = 0;
> >       conf.group_id = port_id;
>

[PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Harold Huang]

When kni driver calls eth_kni_start to start device, some fields such as
min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
value. This is unexpected and sometimes we could not change the kni
device mtu with ip link command.

Fixes: ff1e35fb5f83 ("kni: calculate MTU from mbuf size")
Cc: stable@dpdk.org
Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
---
 drivers/net/kni/rte_eth_kni.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
index c428caf441..ba58d9dbae 100644
--- a/drivers/net/kni/rte_eth_kni.c
+++ b/drivers/net/kni/rte_eth_kni.c
@@ -124,7 +124,7 @@ eth_kni_start(struct rte_eth_dev *dev)
 	struct pmd_internals *internals = dev->data->dev_private;
 	uint16_t port_id = dev->data->port_id;
 	struct rte_mempool *mb_pool;
-	struct rte_kni_conf conf;
+	struct rte_kni_conf conf = { 0 };
 	const char *name = dev->device->name + 4; /* remove net_ */
 
 	mb_pool = internals->rx_queues[0].mb_pool;
-- 
2.27.0

Re: [PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Ferruh Yigit]

On 3/3/2022 2:18 AM, Harold Huang wrote:
> When kni driver calls eth_kni_start to start device, some fields such as
> min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
> kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
> value. This is unexpected and sometimes we could not change the kni
> device mtu with ip link command.
> 
> Fixes: ff1e35fb5f83 ("kni: calculate MTU from mbuf size")
> Cc: stable@dpdk.org
> Signed-off-by: Harold Huang <baymaxhuang@gmail.com>

Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

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

Re: [PATCH] net/kni: initialize rte_kni_conf to 0 before using it

[Ferruh Yigit]

On 3/3/2022 2:18 AM, Harold Huang wrote:
> When kni driver calls eth_kni_start to start device, some fields such as
> min_mtu and max_mtu of rte_kni_conf are not initialized. It will cause
> kni_ioctl_create create a kni netdevice with a random min_mtu and max_mtu
> value. This is unexpected and sometimes we could not change the kni
> device mtu with ip link command.
> 
> Fixes: ff1e35fb5f83 ("kni: calculate MTU from mbuf size")
> Cc: stable@dpdk.org
> Signed-off-by: Harold Huang <baymaxhuang@gmail.com>
> ---
>   drivers/net/kni/rte_eth_kni.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/kni/rte_eth_kni.c b/drivers/net/kni/rte_eth_kni.c
> index c428caf441..ba58d9dbae 100644
> --- a/drivers/net/kni/rte_eth_kni.c
> +++ b/drivers/net/kni/rte_eth_kni.c
> @@ -124,7 +124,7 @@ eth_kni_start(struct rte_eth_dev *dev)
>   	struct pmd_internals *internals = dev->data->dev_private;
>   	uint16_t port_id = dev->data->port_id;
>   	struct rte_mempool *mb_pool;
> -	struct rte_kni_conf conf;
> +	struct rte_kni_conf conf = { 0 };

This is causing build error [1], updated in next-net [2] to fix.

Normally '{ 0 }' should be universal zero-initializer, but I guess
it fails because of old compiler version:
gcc 4.8.5 "cc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-44)"


[1]
FAILED: drivers/a715181@@tmp_rte_net_kni@sta/net_kni_rte_eth_kni.c.o
../drivers/net/kni/rte_eth_kni.c: In function 'eth_kni_start':
../drivers/net/kni/rte_eth_kni.c:127:9:
	error: missing braces around initializer [-Werror=missing-braces]
   struct rte_kni_conf conf = { 0 };
          ^

[2]
struct rte_kni_conf conf = {{0}};

>   	const char *name = dev->device->name + 4; /* remove net_ */
>   
>   	mb_pool = internals->rx_queues[0].mb_pool;