[U-Boot] [PATCH 3/3] usb: gadget: fastboot: terminate commands with NULL

Eric Nelson
2014-10-01T21:23:51Z

Thanks Steve,

On 10/01/2014 01:40 PM, Steve Rae wrote:
>
>
> On 14-09-30 12:05 PM, Eric Nelson wrote:
>> Without NULL termination, various commands will read past the
>> end of input. In particular, this was noticed with error()
>> calls in cb_getvar and simple_strtoul() in cb_download.
>>
>> Since the download callback happens elsewhere, the 4k buffer
>> should always be sufficient to handle command arguments.
>>
>> Signed-off-by: Eric Nelson <eric.nelson@boundarydevices.com>
>> ---
>> drivers/usb/gadget/f_fastboot.c | 7 +++++++
>> 1 file changed, 7 insertions(+)
>>
>> diff --git a/drivers/usb/gadget/f_fastboot.c
>> b/drivers/usb/gadget/f_fastboot.c
>> index 86700f5..0950ea8 100644
>> --- a/drivers/usb/gadget/f_fastboot.c
>> +++ b/drivers/usb/gadget/f_fastboot.c
>> @@ -542,6 +542,13 @@ static void rx_handler_command(struct usb_ep *ep,
>> struct usb_request *req)
>> error("unknown command: %s\n", cmdbuf);
>> fastboot_tx_write_str("FAILunknown command");
>> } else {
>> + if (req->actual < req->length) {
>> + u8 *buf = (u8 *)req->buf;
>> + buf[req->actual] = 0;
>> + func_cb(ep, req);
>> + } else {
>> + error("buffer overflow\n");
> fastboot_tx_write_str("FAILbuffer overflow");
> ADD this line
>> + }
>> func_cb(ep, req);
> AND delete this line (otherwise the func_cb() is called twice!!!)
>> }
>>

Ouch. It appears I pooched the patch when trying to make checkpatch
happy with the extra(neous) braces.

I'll forward V2 shortly.

Regards,

Eric