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 a76116f422c442ab691b4dcabb25613486d34360 ]
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: 89ae89f53d20 ("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 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 ec19942321e6d..0f5906f43d7ca 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -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;