RFR: 8038296 sun/tools/jinfo/Basic.sh: java.io.IOException: Command failed in target VM

[Dmitry Samersoff]

Staffan,

> Yes, that will find problems when trying to convert something like
> ‘bla’. It will not capture the case where the input string is a too
> large (or small) value (value < LONG_MIN or > LONG_MAX). To capture
> both cases it looks like we need something like:
>   errno = 0;
>   char* end;
>   int probe_typess = (int) strtol(probe, &end, 10);
>   if (end == probe || errno) {
>     return JNI_ERR;
>   }

As probe_typess is positive and you are converting long to int
It's be better to check value boundaries explicitly:

   char* end;
   long ptl = strtol(probe, &end, 10);
   if (end == probe || ptl < 0 || ptl > MAX_INT) {
     return JNI_ERR;
   }

   int probe_typess = (int) ptl;


-Dmitry


On 2014-03-25 17:35, Staffan Larsen wrote:
> 
> On 25 mar 2014, at 13:46, Dmitry Samersoff
> <dmitry.samersoff at oracle.com> wrote:
> 
>> Staffan,
>> 
>> strtol() sets errno in two cases -
>> 
>> ERANGE if supplied value is less then LONG_MIN or greater than
>> LONG_MAX EINVAL if supplied base is not supported.
>> 
>> if you pass probe == 'bla', strtol just return 0 and errno will not
>> be set. So I'm not sure that check for errno has any value here.
>> 
>> One of possible way to check that supplied value is convertible to
>> long is
>> 
>> char *eptr = probe; strtol(probe, (char **)&eptr, 10); if (eptr ==
>> probe) { // we can't convert supplied value return JNI_ERR; }
> 
> Yes, that will find problems when trying to convert something like
> ‘bla’. It will not capture the case where the input string is a too
> large (or small) value (value < LONG_MIN or > LONG_MAX). To capture
> both cases it looks like we need something like:
> 
> errno = 0; char* end; int probe_typess = (int) strtol(probe, &end,
> 10); if (end == probe || errno) { return JNI_ERR; }
> 
> 
> /Staffan
> 
>> 
>> -Dmitry
>> 
>> 
>> On 2014-03-25 11:31, Staffan Larsen wrote:
>>> attachListener_solaris.cpp calls atoi() and then checks errno to
>>> see if any errors occurred. The problem is that atoi() does not
>>> set errno, so some old value of errno is checked which sometimes
>>> causes the function to fail.
>>> 
>>> The fix is to replace atoi() with strtol() which does set errno.
>>> But errno is only set if an error occurred and not set to 0 in
>>> case of success. Thus, I set errno to 0 before calling strtol()
>>> and check the value afterwards.
>>> 
>>> Verified with a JPRT run.
>>> 
>>> webrev: http://cr.openjdk.java.net/~sla/8038296/webrev.00/ bug:
>>> https://bugs.openjdk.java.net/browse/JDK-8038296
>>> 
>>> Thanks, /Staffan
>>> 
>> 
>> 
>> -- Dmitry Samersoff Oracle Java development team, Saint Petersburg,
>> Russia * I would love to change the world, but they won't give me
>> the sources.
> 


-- 
Dmitry Samersoff
Oracle Java development team, Saint Petersburg, Russia
* I would love to change the world, but they won't give me the sources.