[PATCH 3/4] fastboot: Fix usage of ubiformat for UBI image transfers

[Sascha Hauer]

On Tue, Feb 16, 2016 at 07:54:47PM +0100, Markus Pargmann wrote:
> Currently all fastboot flash commands with UBI images are handled by a
> final call to 'ubiformat'. This only makes sense for flash commands
> where the target file is a mtd device. If we just want to transfer a UBI
> image we would expect a simple copy to the correct location.
> 
> This patch checks if the destination file is a MTD device by opening it
> and calling an ioctl MEMGETINFO. Only for MTD devices, ubiformat is
> called.
> 
> Signed-off-by: Markus Pargmann <mpa at pengutronix.de>
> ---
>  drivers/usb/gadget/f_fastboot.c | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/gadget/f_fastboot.c b/drivers/usb/gadget/f_fastboot.c
> index bf28f7c22aaa..192c0d6eb7f4 100644
> --- a/drivers/usb/gadget/f_fastboot.c
> +++ b/drivers/usb/gadget/f_fastboot.c
> @@ -686,7 +686,21 @@ static void cb_flash(struct usb_ep *ep, struct usb_request *req, const char *cmd
>  	}
>  
>  	if (filetype == filetype_ubi) {
> -		char *cmd = asprintf("ubiformat -y -f %s %s", FASTBOOT_TMPFILE, filename);
> +		char *cmd;
> +		int fd;
> +		struct mtd_info_user meminfo;
> +
> +		fd = open(filename, O_RDONLY);
> +		if (!fd)
> +			goto copy;

0 is a valid file descriptor, though one that will never be returned by
open(). You want to check for fd < 0 here.

> +
> +		ret = ioctl(fd, MEMGETINFO, &meminfo);
> +		close(fd);
> +		/* Not a MTD device, ubiformat is not a valid operation */
> +		if (ret)
> +			goto copy;
> +
> +		cmd = asprintf("ubiformat -y -f %s %s", FASTBOOT_TMPFILE, filename);

Hm, ubiformat should get a C api.

Sascha

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