On 09.12.22 09:06, Gerhard Engleder wrote:
On 09.12.22 01:43, Saeed Mahameed wrote:
+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..
I will ensure that no double free will happen when ndo_close is called.
Other drivers like igc/igb/netsec/stmmac also fail silently and
I don't see any measures against double free in this drivers.
mvneta forwards the return value of open. How are these drivers
solving this issue? I cannot find this detail, but I also do not
believe that all this drivers are buggy.
gerhard
