json: fix potential overflow #39
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The code:
```cpp
while(!EMPTY_STRING(input) && stream.push(*index) != json::reader::REJECTED)
{
index++;
}
```
Runs into an issue because `EMPTY_STRING(input)` is used to check for
null-pointer ending, but `input` is never incremented during the loop.
As such, an overflow will happen when `index` has incremented beyond
it's buffer and `*index` is run. This triggers an overflow on the
`input` buffer as `index` is declared as:
`const char *index = json::parsing::tlws(input);`
Instead of checking for an empty string on `input` we should check it on
`index`.
Signed-off-by: David Korczynski <david@adalogics.com>
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The code:
Runs into an issue because
EMPTY_STRING(input)is used to check for null-pointer ending, butinputis never incremented during the loop. As such, an overflow will happen whenindexhas incremented beyond it's buffer and*indexis run. This triggers an overflow on theinputbuffer asindexis declared as:const char *index = json::parsing::tlws(input);Instead of checking for an empty string on
inputwe should check it onindex.