On 08 Dec 06:40, Gerhard Engleder wrote:
Implement setup of BPF programs for XDP RX path with command
XDP_SETUP_PROG of ndo_bpf(). This is prework for XDP RX path support.
Signed-off-by: Gerhard Engleder <gerhard@xxxxxxxxxxxxxxxxxxxxx>
[ ... ]
+int tsnep_xdp_setup_prog(struct tsnep_adapter *adapter, struct bpf_prog *prog,
+ struct netlink_ext_ack *extack)
+{
+ struct net_device *dev = adapter->netdev;
+ bool if_running = netif_running(dev);
+ struct bpf_prog *old_prog;
+
+ if (if_running)
+ tsnep_netdev_close(dev);
+
+ old_prog = xchg(&adapter->xdp_prog, prog);
+ if (old_prog)
+ bpf_prog_put(old_prog);
+
+ if (if_running)
+ tsnep_netdev_open(dev);
this could fail silently, and then cause double free, when close ndo
will be called, the stack won't be aware of the closed state..
