On Fri, Mar 21, 2025 at 05:35:18PM +0300, Dan Carpenter wrote:
> On Mon, Aug 06, 2018 at 11:42:57PM +0300, Dan Carpenter wrote:
> > Hello Martin Blumenstingl,
> >
> > The patch 26503ad25de8: "Bluetooth: btrtl: split the device
> > initialization into smaller parts" from Aug 2, 2018, leads to the
> > following static checker warning:
> >
> > drivers/bluetooth/btrtl.c:592 btrtl_initialize()
> > warn: passing zero to 'ERR_PTR'
> >
> > drivers/bluetooth/btrtl.c
> > 559 btrtl_dev->fw_len = rtl_load_file(hdev, btrtl_dev->ic_info->fw_name,
> > 560 &btrtl_dev->fw_data);
> > 561 if (btrtl_dev->fw_len < 0) {
> > 562 rtl_dev_err(hdev, "firmware file %s not found\n",
> > 563 btrtl_dev->ic_info->fw_name);
> > 564 ret = btrtl_dev->fw_len;
> > 565 goto err_free;
> > 566 }
> > 567
> > 568 if (btrtl_dev->ic_info->cfg_name) {
> > 569 if (postfix) {
> > 570 snprintf(cfg_name, sizeof(cfg_name), "%s-%s.bin",
> > 571 btrtl_dev->ic_info->cfg_name, postfix);
> > 572 } else {
> > 573 snprintf(cfg_name, sizeof(cfg_name), "%s.bin",
> > 574 btrtl_dev->ic_info->cfg_name);
> > 575 }
> > 576 btrtl_dev->cfg_len = rtl_load_file(hdev, cfg_name,
> > 577 &btrtl_dev->cfg_data);
> > 578 if (btrtl_dev->ic_info->config_needed &&
> > 579 btrtl_dev->cfg_len <= 0) {
> > ^^^^^^^^^^^^^^^^^^^^^^^
> > Assume btrtl_dev->cfg_len == 0
> >
>
> This is the length of the firmware file. Does it make sense for
> request_firmware() to load empty files? Probably there is a test for
> this in the firmware code which rejects zero length files?
We don't know the size of the file until we try to read it. Although
kernel_read_file_from_path_initns() perhaps should allow for empty
files, I do agree it seems odd to use the firmware API for 0 length
files.
We should extend tools/testing/selftests/firmware/ to check for this.
Care for a patch?
Luis
