Fix GH-9209: precision 0 -INF #10201
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As suggested by cmb69, this is fixed by changing zend_gcvt() and verifying whether the callers have enough buffer space.
Unfortunately, we can't be sure about that, because zend_strtod.h is public, and |
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Ah right... that's unfortunate.
You mean at the function entry right? |
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Wait how would we even assert for enough buffer space? We can't really use ndigit because it is actually used for precision and having it less than 5 is legal afaik? |
Oh, right! This function is a foot-gun, what's probably the reason it has been removed from the POSIX specs. It may make sense to introduce a new function which also requires the buffer size to be passed (like |
…sses if the appropriate methods are present This introduces the class flag ZEND_ACC_SUBCLASS_SERIALIZABLE, which allows classes which are not serializable / deserializable to become that if a subclass implements the appropriate methods. Setting this flag through the stubs can be done using @subclass-serializable. Introducing this through behaviour a new flag allows for opt-in behaviour, which is backwards compatible. Fixes phpGH-10201
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Also worth noting that you can already "overflow" |
As suggested by cmb69, this is fixed by changing zend_gcvt() and verifying whether the callers have enough buffer space.
The only place that did not allocate enough buffer space was in php_encoding.c. However, it actually uses
safe_emallocwith an offset ofMAX_LENGTH_OF_DOUBLE + 1so it wouldn't have overflowed in practice I guess, but I think it's still better to not rely on the overflow protection and do it properly.