bpf: set maximum number of attached progs to 64 for a single perf tp
cgropu+bpf prog array has a maximum number of 64 programs.
Let us apply the same limit here.
Fixes: e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index b9f8686..86b50aa 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -1447,7 +1447,8 @@ int bpf_prog_array_length(struct bpf_prog_array __rcu *progs)
rcu_read_lock();
prog = rcu_dereference(progs)->progs;
for (; *prog; prog++)
- cnt++;
+ if (*prog != &dummy_bpf_prog.prog)
+ cnt++;
rcu_read_unlock();
return cnt;
}