[PATCH bpf-next 1/2] bpf: Check link_create parameter for multi_kprobe

[Tao Chen]

The target_fd and flags in link_create no used in multi_kprobe
, return -EINVAL if they assigned, keep it same as other link
attach apis.

Fixes: 0dcac2725406 ("bpf: Add multi kprobe link")
Signed-off-by: Tao Chen <chen.dylane@xxxxxxxxx>
---
 kernel/trace/bpf_trace.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 13bef2462..2f206a2a2 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2993,6 +2993,9 @@ int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
 	if (sizeof(u64) != sizeof(void *))
 		return -EOPNOTSUPP;
 
+	if (attr->link_create.target_fd || attr->link_create.flags)
+		return -EINVAL;
+
 	if (!is_kprobe_multi(prog))
 		return -EINVAL;
 
-- 
2.43.0