Re: [PATCH v7 28/52] i386/tdx: Wire TDX_REPORT_FATAL_ERROR with GuestPanic facility

[Xiaoyao Li <xiaoyao.li@intel.com>]

On 2/28/2025 12:30 AM, Francesco Lavra wrote:
> On Fri, 2025-01-24 at 08:20 -0500, Xiaoyao Li wrote:
>> diff --git a/system/runstate.c b/system/runstate.c
>> index 272801d30769..c4244c8915c6 100644
>> --- a/system/runstate.c
>> +++ b/system/runstate.c
>> @@ -565,6 +565,60 @@ static void qemu_system_wakeup(void)
>>       }
>>   }
>>   
>> +static char *tdx_parse_panic_message(char *message)
>> +{
>> +    bool printable = false;
>> +    char *buf = NULL;
>> +    int len = 0, i;
>> +
>> +    /*
>> +     * Although message is defined as a json string, we shouldn't
>> +     * unconditionally treat it as is because the guest generated it
>> and
>> +     * it's not necessarily trustable.
>> +     */
>> +    if (message) {
>> +        /* The caller guarantees the NULL-terminated string. */
>> +        len = strlen(message);
>> +
>> +        printable = len > 0;
>> +        for (i = 0; i < len; i++) {
>> +            if (!(0x20 <= message[i] && message[i] <= 0x7e)) {
>> +                printable = false;
>> +                break;
>> +            }
>> +        }
>> +    }
>> +
>> +    if (len == 0) {
>> +        buf = g_malloc(1);
>> +        buf[0] = '\0';
>> +    } else {
>> +        if (!printable) {
>> +            /* 3 = length of "%02x " */
>> +            buf = g_malloc(len * 3);
>> +            for (i = 0; i < len; i++) {
>> +                if (message[i] == '\0') {
>> +                    break;
>> +                } else {
>> +                    sprintf(buf + 3 * i, "%02x ", message[i]);
>> +                }
>> +            }
>> +            if (i > 0) {
>> +                /* replace the last ' '(space) to NULL */
>> +                buf[i * 3 - 1] = '\0';
>> +            } else {
>> +                buf[0] = '\0';
>> +            }
>> +
>> +        } else {
>> +            buf = g_malloc(len);
>> +            memcpy(buf, message, len);
> 
> This fails to null-terminate the message string in buf.
> 

will just use g_strdup(message);