[PATCH v2] infiniband: i40iw: fix a potential NULL pointer dereference

[xiyuyang19]

From: Xiyu Yang <xiyuyang19@xxxxxxxxxxxx>

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 <xiyuyang19@xxxxxxxxxxxx>
Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx>
---
Changes in v2:
- Release rtnl lock when in_dev_get return NULL

 drivers/infiniband/hw/i40iw/i40iw_main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/infiniband/hw/i40iw/i40iw_main.c b/drivers/infiniband/hw/i40iw/i40iw_main.c
index d44cf33d..d7146fdf 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_main.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_main.c
@@ -1225,6 +1225,10 @@ static void i40iw_add_ipv4_addr(struct i40iw_device *iwdev)
 			const struct in_ifaddr *ifa;
 
 			idev = in_dev_get(dev);
+			if (!idev) {
+				i40iw_pr_err("ipv4 inet device not found\n");
+				break;
+			}
 			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