From 2b658c1c442ec1cd9eec5ead98d68662c40fe645 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Fri, 13 Mar 2026 08:40:25 +0100 Subject: [PATCH] HID: bpf: prevent buffer overflow in hid_hw_request right now the returned value is considered to be always valid. However, when playing with HID-BPF, the return value can be arbitrary big, because it's the return value of dispatch_hid_bpf_raw_requests(), which calls the struct_ops and we have no guarantees that the value makes sense. Fixes: 8bd0488b5ea5 ("HID: bpf: add HID-BPF hooks for hid_hw_raw_requests") Cc: stable@vger.kernel.org Acked-by: Jiri Kosina Signed-off-by: Benjamin Tissoires --- drivers/hid/bpf/hid_bpf_dispatch.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/hid/bpf/hid_bpf_dispatch.c b/drivers/hid/bpf/hid_bpf_dispatch.c index 892aca026ffa..33af17fdc729 100644 --- a/drivers/hid/bpf/hid_bpf_dispatch.c +++ b/drivers/hid/bpf/hid_bpf_dispatch.c @@ -444,6 +444,8 @@ hid_bpf_hw_request(struct hid_bpf_ctx *ctx, __u8 *buf, size_t buf__sz, (u64)(long)ctx, true); /* prevent infinite recursions */ + if (ret > size) + ret = size; if (ret > 0) memcpy(buf, dma_data, ret);