From: Benjamin Tissoires Date: Fri, 13 Mar 2026 07:40:25 +0000 (+0100) Subject: HID: bpf: prevent buffer overflow in hid_hw_request X-Git-Tag: v7.0-rc5~41^2~2 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=2b658c1c442ec1cd9eec5ead98d68662c40fe645;p=thirdparty%2Fkernel%2Flinux.git 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 --- 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);