greybus: Avoid fake flexible array for response data

FORTIFY_SOURCE has been ignoring 0-sized destinations while the kernel
code base has been converted to flexible arrays. In order to enforce
the 0-sized destinations (e.g. with __counted_by), the remaining 0-sized
destinations need to be handled. Instead of converting an empty struct
into using a flexible array, just directly use a pointer without any
additional indirection. Remove struct gb_bootrom_get_firmware_response
and struct gb_fw_download_fetch_firmware_response.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20240304211940.it.083-kees@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kees Cook 2024-03-04 13:19:45 -08:00 committed by Greg Kroah-Hartman
parent 34164202a5
commit 7ba59ac7da
3 changed files with 10 additions and 14 deletions

View File

@ -243,10 +243,10 @@ static int gb_bootrom_get_firmware(struct gb_operation *op)
struct gb_bootrom *bootrom = gb_connection_get_data(op->connection);
const struct firmware *fw;
struct gb_bootrom_get_firmware_request *firmware_request;
struct gb_bootrom_get_firmware_response *firmware_response;
struct device *dev = &op->connection->bundle->dev;
unsigned int offset, size;
enum next_request_type next_request;
u8 *firmware_response;
int ret = 0;
/* Disable timeouts */
@ -280,15 +280,15 @@ static int gb_bootrom_get_firmware(struct gb_operation *op)
goto unlock;
}
if (!gb_operation_response_alloc(op, sizeof(*firmware_response) + size,
GFP_KERNEL)) {
/* gb_bootrom_get_firmware_response contains only a byte array */
if (!gb_operation_response_alloc(op, size, GFP_KERNEL)) {
dev_err(dev, "%s: error allocating response\n", __func__);
ret = -ENOMEM;
goto unlock;
}
firmware_response = op->response->payload;
memcpy(firmware_response->data, fw->data + offset, size);
memcpy(firmware_response, fw->data + offset, size);
dev_dbg(dev, "responding with firmware (offs = %u, size = %u)\n",
offset, size);

View File

@ -270,11 +270,11 @@ static int fw_download_fetch_firmware(struct gb_operation *op)
struct gb_connection *connection = op->connection;
struct fw_download *fw_download = gb_connection_get_data(connection);
struct gb_fw_download_fetch_firmware_request *request;
struct gb_fw_download_fetch_firmware_response *response;
struct fw_request *fw_req;
const struct firmware *fw;
unsigned int offset, size;
u8 firmware_id;
u8 *response;
int ret = 0;
if (op->request->payload_size != sizeof(*request)) {
@ -324,8 +324,8 @@ static int fw_download_fetch_firmware(struct gb_operation *op)
goto put_fw;
}
if (!gb_operation_response_alloc(op, sizeof(*response) + size,
GFP_KERNEL)) {
/* gb_fw_download_fetch_firmware_response contains only a byte array */
if (!gb_operation_response_alloc(op, size, GFP_KERNEL)) {
dev_err(fw_download->parent,
"error allocating fetch firmware response\n");
ret = -ENOMEM;
@ -333,7 +333,7 @@ static int fw_download_fetch_firmware(struct gb_operation *op)
}
response = op->response->payload;
memcpy(response->data, fw->data + offset, size);
memcpy(response, fw->data + offset, size);
dev_dbg(fw_download->parent,
"responding with firmware (offs = %u, size = %u)\n", offset,

View File

@ -232,9 +232,7 @@ struct gb_fw_download_fetch_firmware_request {
__le32 size;
} __packed;
struct gb_fw_download_fetch_firmware_response {
__u8 data[0];
} __packed;
/* gb_fw_download_fetch_firmware_response contains no other data */
/* firmware download release firmware request */
struct gb_fw_download_release_firmware_request {
@ -414,9 +412,7 @@ struct gb_bootrom_get_firmware_request {
__le32 size;
} __packed;
struct gb_bootrom_get_firmware_response {
__u8 data[0];
} __packed;
/* gb_bootrom_get_firmware_response contains no other data */
/* Bootrom protocol Ready to boot request */
struct gb_bootrom_ready_to_boot_request {