On 1/21/20 12:13 AM, Alex Bennée wrote:
>
> Richard Henderson <richard.hender...@linaro.org> writes:
>
>> On 1/20/20 1:48 AM, Alex Bennée wrote:
>>>> + default:
>>>> + sigsegv:
>>>
>>> this label looks a little extraneous.
>>>
>>> Otherwise:
>>>
>>> Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
>>>
>>
>> Look a little further down:
>>
>>> + default:
>>> + sigsegv:
>>> + /* Like force_sig(SIGSEGV). */
>>> + gen_signal(env, TARGET_SIGSEGV, TARGET_SI_KERNEL, 0);
>>> + return;
>>> + }
>>> +
>>> + /*
>>> + * Validate the return address.
>>> + * Note that the kernel treats this the same as an invalid entry point.
>>> + */
>>> + if (get_user_u64(caller, env->regs[R_ESP])) {
>>> + goto sigsegv;
>>> + }
>
> Wouldn't this read better:
>
> /*
> * Validate the entry point. We have already validated the page
> * during translation, now verify the offset.
> */
> switch (env->eip & ~TARGET_PAGE_MASK) {
> case 0x000:
> syscall = TARGET_NR_gettimeofday;
> break;
> case 0x400:
> syscall = TARGET_NR_time;
> break;
> case 0x800:
> syscall = TARGET_NR_getcpu;
> break;
> default:
> syscall = -1;
> break;
> }
>
> /*
> * If we have an invalid entry point or an invalid return address we
> * generate a SIGSEG.
> */
> if (syscall < 0 || get_user_u64(caller, env->regs[R_ESP])) {
> gen_signal(env, TARGET_SIGSEGV, TARGET_SI_KERNEL, 0);
> return;
> }
>
Only if you have a violent goto allergy.
r~
