In PHP static properties are shared between inheriting classes,
unless they are explicitly overwritten. However, because this
functionality was implemented using reference, it was possible
to break the implementation by reassigning the static property
reference.
This is fixed by switching the implementation from using references
to using INDIRECTs, which cannot be affected by userland code.
* PHP-7.2:
Don't keep HashTable.pDestructor in SHM and always set it into ZVAL_PTR_DTOR in zval_array_dup(). Keeping pointer to a function in SHM is not safe because of ASLR.
* PHP-7.1:
Don't keep HashTable.pDestructor in SHM and always set it into ZVAL_PTR_DTOR in zval_array_dup(). Keeping pointer to a function in SHM is not safe because of ASLR.
Prohibit direct update of GC_REFCOUNT(), GC_SET_REFCOUNT(), GC_ADDREF() and GC_DELREF() shoukf be instead.
Added mactros to validate reference-counting (disabled for now).
These macros are going to be used to eliminate race-condintions during reference-counting on data shared between threads.
Hereby, interned strings are supported in thread safe PHP. The patch
implements two types of interned strings
- interning per process, strings are not freed till process end
- interning per request, strings are freed at request end
There is no runtime interning.
With Opcache, all the permanent iterned strings are copied into SHM on
startup, additional copying into SHM might happen on demand.
The file_cache_only option causes the storage to be per process,
furthermore the arena is destroyed per request. Thus, zend_string's
can't survive between request and the permanent flag should not
be set. This is already done with the file cache part, but the
persistency part is used in various scenarios and should respect
this case as well. In this particular bug, the pcre pattern cache
needs to survive between requests and uses pattern strings as hash
keys. One more case relevant here would be various situations where
the flow disables the use of shared memory.
Fix a couple of mistakes that are only relevant if
sizeof(zend_long) > sizeof(size_t).
* Fix cast order in string offset check: Negation should happen
after the (zend_long) cast, otherwise sign extension does not
occur.
* Use Z_UL in zend_inference.
* Use aligned size for HT_USED_SIZE in zend_persist: The issue is
that on x86-32 uint64_t is considered to be 4-aligned, so the
alignment assumption does not hold.
