Commit 49b23575 authored Jun 03, 2020 by Matthieu Baerts Committed by Daniel Borkmann Jun 04, 2020

bpf: Fix unused-var without NETDEVICES

A recent commit added new variables only used if CONFIG_NETDEVICES is
set. A simple fix would be to only declare these variables if the same
condition is valid but Alexei suggested an even simpler solution:

since CONFIG_NETDEVICES doesn't change anything in .h I think the
best is to remove #ifdef CONFIG_NETDEVICES from net/core/filter.c
and rely on sock_bindtoindex() returning ENOPROTOOPT in the extreme
case of oddly configured kernels.

Fixes: 70c58997 ("bpf: Allow SO_BINDTODEVICE opt in bpf_setsockopt")
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200603190347.2310320-1-matthieu.baerts@tessares.net

parent cb8e59cc

net/core/filter.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -4340,8 +4340,6 @@ static int _bpf_setsockopt(struct sock *sk, int level, int optname,
		}
		break;
		case SO_BINDTODEVICE:
		ret = -ENOPROTOOPT;
		#ifdef CONFIG_NETDEVICES
		optlen = min_t(long, optlen, IFNAMSIZ - 1);
		strncpy(devname, optval, optlen);
		devname[optlen] = 0;
		@@ -4360,7 +4358,6 @@ static int _bpf_setsockopt(struct sock *sk, int level, int optname,
		dev_put(dev);
		}
		ret = sock_bindtoindex(sk, ifindex, false);
		#endif
		break;
		default:
		ret = -EINVAL;