bpf: Check link_create.flags parameter for multi_uprobe

The link_create.flags are currently not used for multi-uprobes, so return
-EINVAL if it is set, same as for other attach APIs.

We allow target_fd to have an arbitrary value for multi-uprobe, though,
as there are existing users (libbpf) relying on this.

Fixes: 89ae89f53d ("bpf: Add multi uprobe link")
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250407035752.1108927-2-chen.dylane@linux.dev
This commit is contained in:
Tao Chen 2025-04-07 11:57:52 +08:00 committed by Andrii Nakryiko
parent 243911982a
commit a76116f422

View File

@ -3379,6 +3379,9 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
if (sizeof(u64) != sizeof(void *))
return -EOPNOTSUPP;
if (attr->link_create.flags)
return -EINVAL;
if (!is_uprobe_multi(prog))
return -EINVAL;