ebpf: emit correct src_reg for conditional jumps
ebpf: emit correct src_reg for conditional jumps

Instead of always emitting BPF_REG_X, let's emit BPF_REG_X only when the
source actually is BPF_X. This causes programs generated by the classic
converter to not be importable via bpf(), as the eBPF verifier checks that
the src_reg is correct or 0. While not a problem yet, this will be a
problem when BPF_PROG_DUMP lands, and we can potentially dump and re-import
programs generated by the converter.

Signed-off-by: Tycho Andersen <10c18fcb898ee6b17d6575d444b125d10b3f4d6a@canonical.com>
CC: Alexei Starovoitov <c24c0248770ae98831f8a654310d4c2e07514c61@kernel.org>
CC: Daniel Borkmann <3d0f3b9ddcacec30c4008c5e030e6c13a478cb4f@iogearbox.net>
Acked-by: Daniel Borkmann <3d0f3b9ddcacec30c4008c5e030e6c13a478cb4f@iogearbox.net>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs