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: 70c58997c1 ("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
This commit is contained in:
Matthieu Baerts 2020-06-03 21:03:47 +02:00 committed by Daniel Borkmann
parent cb8e59cc87
commit 49b2357594

View file

@ -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;