[PATCH v10 02/11] efi_loader: capsule: add capsule_on_disk support

[Heinrich Schuchardt <xypron.glpk@gmx.de>]

On 11/30/20 10:12 AM, AKASHI Takahiro wrote:
> Capsule data can be loaded into the system either via UpdateCapsule
> runtime service or files on a file system (of boot device).
> The latter case is called "capsules on disk", and actual updates will
> take place at the next boot time.
>
> In this commit, we will support capsule on disk mechanism.
>
> Please note that U-Boot itself has no notion of "boot device" and
> all the capsule files to be executed will be detected only if they
> are located in a specific directory, \EFI\UpdateCapsule, on a device
> that is identified as a boot device by "BootXXXX" variables.
>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---

<snip />

> +static efi_status_t efi_capsule_scan_dir(u16 ***files, unsigned int *num)
> +{
> +	struct efi_file_handle *dirh;
> +	struct efi_file_info *dirent;
> +	efi_uintn_t dirent_size, tmp_size;
> +	unsigned int count;
> +	u16 **tmp_files;
> +	efi_status_t ret;
> +
> +	ret = find_boot_device();
> +	if (ret == EFI_NOT_FOUND) {
> +		EFI_PRINT("EFI Capsule: bootdev is not set\n");
> +		*num = 0;
> +		return EFI_SUCCESS;
> +	} else if (ret != EFI_SUCCESS) {
> +		return EFI_DEVICE_ERROR;
> +	}
> +
> +	/* count capsule files */
> +	ret = EFI_CALL((*bootdev_root->open)(bootdev_root, &dirh,
> +					     EFI_CAPSULE_DIR,
> +					     EFI_FILE_MODE_READ, 0));
> +	if (ret != EFI_SUCCESS) {
> +		*num = 0;
> +		return EFI_SUCCESS;
> +	}
> +
> +	dirent_size = 256;
> +	dirent = malloc(dirent_size);
> +	if (!dirent)
> +		return EFI_OUT_OF_RESOURCES;
> +
> +	count = 0;
> +	while (1) {
> +		tmp_size = dirent_size;
> +		ret = EFI_CALL((*dirh->read)(dirh, &tmp_size, dirent));
> +		if (ret == EFI_BUFFER_TOO_SMALL) {
> +			dirent = realloc(dirent, tmp_size);
> +			if (!dirent) {

If realloc() fails, you should free the *old* pointer.

Best regards

Heinrich

> +				ret = EFI_OUT_OF_RESOURCES;
> +				goto err;
> +			}