On Fri, Jul 31, 2020 at 01:01:39AM +0300, Tomas Winkler wrote:
wired_cmd_repeater_auth_stream_req_in has a variable length array at the end. we use struct_size() overflow macro to determine the size for the allocation and sending size. This also fixes bug in case number of streams is > 0 in the original submission. This bug was not triggered as the number of streams is always one.
Fixes: c56967d674e3 (mei: hdcp: Replace one-element array with flexible-array member) Fixes: commit 0a1af1b5c18d ("misc/mei/hdcp: Verify M_prime")
^^^^ I think the _commit_ word above is unnecessary.
Cc: "Gustavo A. R. Silva" gustavo@embeddedor.com Cc: Ramalingam C ramalingam.c@intel.com Cc: stable@vger.kernel.org v5.1+
Greg,
Notice that this patch is fine as is for -next, only. This becomes suitable for -stable as long as commit c56967d674e3 (mei: hdcp: Replace one-element array with flexible-array member) is applied to -stable, too. Otherwise, a separate patch that leaves the one-element array in struct wired_cmd_repeater_auth_stream_req_in in place needs to be crafted. With this taken into account, here is my
Reviewed-by: Gustavo A. R. Silva gustavoars@kernel.org
Thanks for the changes, Tomas. -- Gustavo
Signed-off-by: Tomas Winkler tomas.winkler@intel.com
V4:
- Fix typo in the subject. (Gustavo)
- Fix dereferencing pointer in send. (Gustavo)
V3:
- Fix commit message with more info and another patch it fixes (Gustavo)
- Target stable. (Gustavo)
V2: Check for allocation failure.
drivers/misc/mei/hdcp/mei_hdcp.c | 40 +++++++++++++++++++------------- 1 file changed, 24 insertions(+), 16 deletions(-)
diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c index d1d3e025ca0e..9ae9669e46ea 100644 --- a/drivers/misc/mei/hdcp/mei_hdcp.c +++ b/drivers/misc/mei/hdcp/mei_hdcp.c @@ -546,38 +546,46 @@ static int mei_hdcp_verify_mprime(struct device *dev, struct hdcp_port_data *data, struct hdcp2_rep_stream_ready *stream_ready) {
- struct wired_cmd_repeater_auth_stream_req_in
verify_mprime_in = { { 0 } };
- struct wired_cmd_repeater_auth_stream_req_in *verify_mprime_in; struct wired_cmd_repeater_auth_stream_req_out verify_mprime_out = { { 0 } }; struct mei_cl_device *cldev; ssize_t byte;
- size_t cmd_size;
if (!dev || !stream_ready || !data) return -EINVAL; cldev = to_mei_cl_device(dev);
- verify_mprime_in.header.api_version = HDCP_API_VERSION;
- verify_mprime_in.header.command_id = WIRED_REPEATER_AUTH_STREAM_REQ;
- verify_mprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
- verify_mprime_in.header.buffer_len =
- cmd_size = struct_size(verify_mprime_in, streams, data->k);
- if (cmd_size == SIZE_MAX)
return -EINVAL;- verify_mprime_in = kzalloc(cmd_size, GFP_KERNEL);
- if (!verify_mprime_in)
return -ENOMEM;- verify_mprime_in->header.api_version = HDCP_API_VERSION;
- verify_mprime_in->header.command_id = WIRED_REPEATER_AUTH_STREAM_REQ;
- verify_mprime_in->header.status = ME_HDCP_STATUS_SUCCESS;
- verify_mprime_in->header.buffer_len = WIRED_CMD_BUF_LEN_REPEATER_AUTH_STREAM_REQ_MIN_IN;
- verify_mprime_in.port.integrated_port_type = data->port_type;
- verify_mprime_in.port.physical_port = (u8)data->fw_ddi;
- verify_mprime_in.port.attached_transcoder = (u8)data->fw_tc;
- verify_mprime_in->port.integrated_port_type = data->port_type;
- verify_mprime_in->port.physical_port = (u8)data->fw_ddi;
- verify_mprime_in->port.attached_transcoder = (u8)data->fw_tc;
- memcpy(verify_mprime_in->m_prime, stream_ready->m_prime, HDCP_2_2_MPRIME_LEN);
- drm_hdcp_cpu_to_be24(verify_mprime_in->seq_num_m, data->seq_num_m);
- memcpy(verify_mprime_in.m_prime, stream_ready->m_prime,
HDCP_2_2_MPRIME_LEN);- drm_hdcp_cpu_to_be24(verify_mprime_in.seq_num_m, data->seq_num_m);
- memcpy(verify_mprime_in.streams, data->streams,
- memcpy(verify_mprime_in->streams, data->streams, array_size(data->k, sizeof(*data->streams)));
- verify_mprime_in.k = cpu_to_be16(data->k);
- verify_mprime_in->k = cpu_to_be16(data->k);
- byte = mei_cldev_send(cldev, (u8 *)&verify_mprime_in,
sizeof(verify_mprime_in));
- byte = mei_cldev_send(cldev, (u8 *)verify_mprime_in, cmd_size);
- kfree(verify_mprime_in); if (byte < 0) { dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte); return byte;
-- 2.25.4