RDMA/cxgb4: add null-ptr-check after ip_dev_find()

[ Upstream commit ef42520240aacfc0d46c8d780c051d135a8dc9b7 ]

ip_dev_find() may return NULL and assign it to pdev which is
dereferenced later.
Fix this by checking the return value of ip_dev_find() for NULL
similar to the way it is done with other instances of said function.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 1cab775c3e75 ("RDMA/cxgb4: Fix LE hash collision bug for passive open connection")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Link: https://lore.kernel.org/r/20230201172103.17261-1-n.zhandarovich@fintech.ru
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 499a425..ea3ddf0 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -4144,6 +4144,10 @@ static int rx_pkt(struct c4iw_dev *dev, struct sk_buff *skb)
 
        if (neigh->dev->flags & IFF_LOOPBACK) {
                pdev = ip_dev_find(&init_net, iph->daddr);
+               if (!pdev) {
+                       pr_err("%s - failed to find device!\n", __func__);
+                       goto free_dst;
+               }
                e = cxgb4_l2t_get(dev->rdev.lldi.l2t, neigh,
                                    pdev, 0);
                pi = (struct port_info *)netdev_priv(pdev);