bpf: fix bpf_perf_event_read() loop upper bound

Verifier rejects programs incorrectly.

Fixes: 35578d798400 ("bpf: Implement function bpf_perf_event_read()")
Cc: Kaixu Xia <xiakaixu@huawei.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Wei-Chun Chao <weichunc@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 48e1c71..ed12e38 100644 (file)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -853,7 +853,7 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id)
        if (!map)
                return 0;
 
-       for (i = 0; i <= ARRAY_SIZE(func_limit); i++) {
+       for (i = 0; i < ARRAY_SIZE(func_limit); i++) {
                bool_map = (map->map_type == func_limit[i].map_type);
                bool_func = (func_id == func_limit[i].func_id);
                /* only when map & func pair match it can continue.