[PATCH] 6788196: Array bounds checks in io_util.c rely on undefined behaviour

[Andrew Haley]

Gary Benson wrote:
> Hi Martin,
> 
> I like your method of avoiding the overflow, it's a nice idea.
> I've attached an updated version of my original patch, with that,
> and with an expanded comment too, to make sure the fix doesn't
> get reverted later on in the interests of readability or whatever.
> 
> Can I ask that you file a seperate bug for your other changes?
> They're not specifically related to 6788196, and I feel it
> confuses the issue somewhat having a bunch of unrelated changes
> in the patch.

> Martin Buchholz wrote:

There are some indentation SNAFUs here.  Maybe due to tab width set to
4?


>> @@ -196,19 +203,19 @@ throwFileNotFoundException(JNIEnv *env,
>>  throwFileNotFoundException(JNIEnv *env, jstring path)
>>  {
>>      char buf[256];
>> -    int n;
>> +    jint n;
>>      jobject x;
>>      jstring why = NULL;
>>
>>      n = JVM_GetLastErrorString(buf, sizeof(buf));
>>      if (n > 0) {
>> -    why = JNU_NewStringPlatform(env, buf);
>> +        why = JNU_NewStringPlatform(env, buf);

^ here

>>      }
>>      x = JNU_NewObjectByName(env,
>>                  "java/io/FileNotFoundException",
>>                  "(Ljava/lang/String;Ljava/lang/String;)V",
>>                  path, why);
>>      if (x != NULL) {
>> -    (*env)->Throw(env, x);
>> +        (*env)->Throw(env, x);


^ here

>>      }
>>  }