Commit 70c58997 authored by Ferenc Fejes's avatar Ferenc Fejes Committed by Alexei Starovoitov
Browse files

bpf: Allow SO_BINDTODEVICE opt in bpf_setsockopt 



Extending the supported sockopts in bpf_setsockopt with
SO_BINDTODEVICE. We call sock_bindtoindex with parameter
lock_sk = false in this context because we already owning
the socket.

Signed-off-by: default avatarFerenc Fejes <fejes@inf.elte.hu>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/4149e304867b8d5a606a305bc59e29b063e51f49.1590871065.git.fejes@inf.elte.hu
parent 8ea204c2

net/core/filter.c

+27 −1
Original line number Diff line number Diff line
@@ -4248,6 +4248,9 @@ static const struct bpf_func_proto bpf_get_socket_uid_proto = { 
static int _bpf_setsockopt(struct sock *sk, int level, int optname,

			   char *optval, int optlen, u32 flags)

{

	char devname[IFNAMSIZ];

	struct net *net;

	int ifindex;

	int ret = 0;

	int val;
@@ -4257,7 +4260,7 @@ static int _bpf_setsockopt(struct sock *sk, int level, int optname, 
	sock_owned_by_me(sk);



	if (level == SOL_SOCKET) {

		if (optlen != sizeof(int))

		if (optlen != sizeof(int) && optname != SO_BINDTODEVICE)

			return -EINVAL;

		val = *((int *)optval);
@@ -4298,6 +4301,29 @@ static int _bpf_setsockopt(struct sock *sk, int level, int optname, 
				sk_dst_reset(sk);

			}

			break;

		case SO_BINDTODEVICE:

			ret = -ENOPROTOOPT;

#ifdef CONFIG_NETDEVICES

			optlen = min_t(long, optlen, IFNAMSIZ - 1);

			strncpy(devname, optval, optlen);

			devname[optlen] = 0;



			ifindex = 0;

			if (devname[0] != '\0') {

				struct net_device *dev;



				ret = -ENODEV;



				net = sock_net(sk);

				dev = dev_get_by_name(net, devname);

				if (!dev)

					break;

				ifindex = dev->ifindex;

				dev_put(dev);

			}

			ret = sock_bindtoindex(sk, ifindex, false);

#endif

			break;

		default:

			ret = -EINVAL;

		}

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