Re: [Qemu-devel] [PATCH 1/2] hw: fw_cfg: ensure reboot_time is nonegative

[Markus Armbruster]

Gerd Hoffmann <address@hidden> writes:

>> -    /* validate the input */
>> -    if (reboot_timeout > 0xffff) {
>> -        error_report("reboot timeout is larger than 65535, force it to 
>> 65535.");
>> -        reboot_timeout = 0xffff;
>> +
>> +    if (reboot_timeout >= 0) {
>> +        /* validate the input */
>> +        if (reboot_timeout > 0xffff) {
>> +            error_report("reboot timeout is larger than 65535,"
>> +                         "force it to 65535.");
>> +            reboot_timeout = 0xffff;
>> +        }
>> +        fw_cfg_add_file(s, "etc/boot-fail-wait",
>> +                        g_memdup(&reboot_timeout, 4), 4);
>>      }
>
> Hmm, values > 0xffff are reported and values < 0 are silently ignored.
> I think we should be consistent here.
> I'd suggest report and exit in both cases,

Agreed.  If the user specifies a value outside acceptable limits,
rejecting it is simpler than "correcting" it.  "Corrections" may look
convenient, but they're not worth the additional interface complexity.

> i.e. use error_setg(..., &error_fatal);

In case you mean something like

    error_setg(&error_fatal, "reboot timeout is larger than 65535");

I'd like to point to error.h:

 * Please don't error_setg(&error_fatal, ...), use error_report() and
 * exit(), because that's more obvious.