2019-12-26 13:23:41

by Xiyu Yang

[permalink] [raw]
Subject: [PATCH v3] infiniband: i40iw: fix a potential NULL pointer dereference

From: Xiyu Yang <[email protected]>

in_dev_get may return a NULL object. The fix handles the situation
by adding a check to avoid NULL pointer dereference on idev,
as pick_local_ipaddrs does.

Signed-off-by: Xiyu Yang <[email protected]>
Signed-off-by: Xin Tan <[email protected]>
---
Changes in v2:
- Release rtnl lock when in_dev_get return NULL
Changes in v3:
- Continue the next loop when in_dev_get return NULL

drivers/infiniband/hw/i40iw/i40iw_main.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/infiniband/hw/i40iw/i40iw_main.c b/drivers/infiniband/hw/i40iw/i40iw_main.c
index d44cf33d..2386143 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_main.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_main.c
@@ -1225,6 +1225,8 @@ static void i40iw_add_ipv4_addr(struct i40iw_device *iwdev)
const struct in_ifaddr *ifa;

idev = in_dev_get(dev);
+ if (!idev)
+ continue;
in_dev_for_each_ifa_rtnl(ifa, idev) {
i40iw_debug(&iwdev->sc_dev, I40IW_DEBUG_CM,
"IP=%pI4, vlan_id=%d, MAC=%pM\n", &ifa->ifa_address,
--
2.7.4


2019-12-26 14:41:10

by Leon Romanovsky

[permalink] [raw]
Subject: Re: [PATCH v3] infiniband: i40iw: fix a potential NULL pointer dereference

On Thu, Dec 26, 2019 at 09:21:56PM +0800, [email protected] wrote:
> From: Xiyu Yang <[email protected]>
>
> in_dev_get may return a NULL object. The fix handles the situation
> by adding a check to avoid NULL pointer dereference on idev,
> as pick_local_ipaddrs does.
>
> Signed-off-by: Xiyu Yang <[email protected]>
> Signed-off-by: Xin Tan <[email protected]>
> ---
> Changes in v2:
> - Release rtnl lock when in_dev_get return NULL
> Changes in v3:
> - Continue the next loop when in_dev_get return NULL
>
> drivers/infiniband/hw/i40iw/i40iw_main.c | 2 ++
> 1 file changed, 2 insertions(+)
>

Thanks,
Reviewed-by: Leon Romanovsky <[email protected]>

2019-12-28 19:52:34

by Markus Elfring

[permalink] [raw]
Subject: Re: [PATCH v3] infiniband: i40iw: fix a potential NULL pointer dereference

> in_dev_get may return a NULL object.

I would prefer a wording like “A null pointer can be returned by in_dev_get().”.


> The fix handles the situation
> by adding a check to avoid NULL pointer dereference on idev,
> as pick_local_ipaddrs does.

How do you think about the wording suggestion “Thus add a corresponding check
so that a null pointer dereference will be avoided at this place.”?

Please add also the tag “Fixes” to your change description.

Regards,
Markus