bpf: fix check_map_func_compatibility logic
authorAlexei Starovoitov <ast@fb.com>
Thu, 28 Apr 2016 01:56:21 +0000 (18:56 -0700)
committerDavid S. Miller <davem@davemloft.net>
Thu, 28 Apr 2016 21:29:45 +0000 (17:29 -0400)
commit6aff67c85c9e5a4bc99e5211c1bac547936626ca
tree3be9fa8e180334d6f8e0c5edb5e47f8113f4b2f4
parent92117d8443bc5afacc8d5ba82e541946310f106e
bpf: fix check_map_func_compatibility logic

The commit 35578d798400 ("bpf: Implement function bpf_perf_event_read() that get the selected hardware PMU conuter")
introduced clever way to check bpf_helper<->map_type compatibility.
Later on commit a43eec304259 ("bpf: introduce bpf_perf_event_output() helper") adjusted
the logic and inadvertently broke it.
Get rid of the clever bool compare and go back to two-way check
from map and from helper perspective.

Fixes: a43eec304259 ("bpf: introduce bpf_perf_event_output() helper")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
kernel/bpf/verifier.c