RDMA/rxe: Use rdma_read_gid_attr_ndev_rcu to access netdev

Use rdma_read_gid_attr_ndev_rcu() to access netdevice attached to GID
entry under rcu lock.

This ensures that while working on the netdevice of the GID, it doesn't
get freed.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Parav Pandit 2019-05-02 10:48:05 +03:00 committed by Jason Gunthorpe
parent adb4a57a7a
commit dab2175800
1 changed files with 12 additions and 3 deletions

View File

@ -458,7 +458,7 @@ struct sk_buff *rxe_init_packet(struct rxe_dev *rxe, struct rxe_av *av,
int paylen, struct rxe_pkt_info *pkt)
{
unsigned int hdr_len;
struct sk_buff *skb;
struct sk_buff *skb = NULL;
struct net_device *ndev;
const struct ib_gid_attr *attr;
const int port_num = 1;
@ -466,7 +466,6 @@ struct sk_buff *rxe_init_packet(struct rxe_dev *rxe, struct rxe_av *av,
attr = rdma_get_gid_attr(&rxe->ib_dev, port_num, av->grh.sgid_index);
if (IS_ERR(attr))
return NULL;
ndev = attr->ndev;
if (av->network_type == RDMA_NETWORK_IPV4)
hdr_len = ETH_HLEN + sizeof(struct udphdr) +
@ -475,16 +474,26 @@ struct sk_buff *rxe_init_packet(struct rxe_dev *rxe, struct rxe_av *av,
hdr_len = ETH_HLEN + sizeof(struct udphdr) +
sizeof(struct ipv6hdr);
rcu_read_lock();
ndev = rdma_read_gid_attr_ndev_rcu(attr);
if (IS_ERR(ndev)) {
rcu_read_unlock();
goto out;
}
skb = alloc_skb(paylen + hdr_len + LL_RESERVED_SPACE(ndev),
GFP_ATOMIC);
if (unlikely(!skb))
if (unlikely(!skb)) {
rcu_read_unlock();
goto out;
}
skb_reserve(skb, hdr_len + LL_RESERVED_SPACE(ndev));
/* FIXME: hold reference to this netdev until life of this skb. */
skb->dev = ndev;
rcu_read_unlock();
if (av->network_type == RDMA_NETWORK_IPV4)
skb->protocol = htons(ETH_P_IP);
else