6.15-stable review patch. If anyone has any objections, please let me know.
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From: Tao Chen chen.dylane@linux.dev
[ Upstream commit 243911982aa9faf4361aa952f879331ad66933fe ]
The link_create.flags are currently not used for multi-kprobes, so return -EINVAL if it is set, same as for other attach APIs.
We allow target_fd, on the other hand, to have an arbitrary value for multi-kprobe, as there are existing users (libbpf) relying on this.
Fixes: 0dcac2725406 ("bpf: Add multi kprobe link") Signed-off-by: Tao Chen chen.dylane@linux.dev Signed-off-by: Andrii Nakryiko andrii@kernel.org Link: https://lore.kernel.org/bpf/20250407035752.1108927-1-chen.dylane@linux.dev Signed-off-by: Sasha Levin sashal@kernel.org --- 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 187dc37d61d4a..ec19942321e6d 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -2987,6 +2987,9 @@ 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.flags) + return -EINVAL; + if (!is_kprobe_multi(prog)) return -EINVAL;