In the test, I have an internal `__call` function for `_ZendTestMagicCallForward` that calls the global function with name `$name` via `call_user_function`.
Note that observer writes the pointer to the previously observed frame in the last temporary of the new call frame (`*prev_observed_frame`).
The following happens:
First, we call `$test->callee`, this will be handled via a trampoline with T=2 for the two arguments. The call frame is allocated at this point. This call frame is not observed because it has `ZEND_ACC_CALL_VIA_TRAMPOLINE` set. Next we use `ZEND_CALL_TRAMPOLINE` to call the trampoline, this reuses the stack frame allocated earlier with T=2, but this time it is observed. The pointer to the previous frame is written outside of the call frame because `T` is too small (should be 3). We are now in the internal function `_ZendTestMagicCallForward::__call` where we call the global function `callee`. This will push a new call frame which will overlap `*prev_observed_frame`. This value gets overwritten by `zend_init_func_execute_data` when `EX(opline)` is set because `*prev_observed_frame` overlaps with `EX(opline)`. From now on, `*prev_observed_frame` is corrupted. When `zend_observer_fcall_end` is called this will result in reading wrong value `*prev_observed_frame` into `current_observed_frame`. This causes issues in `zend_observer_fcall_end_all` leading to the segfault we observe.
Despite function with `ZEND_ACC_CALL_VIA_TRAMPOLINE` not being observed, the reuse of call frames makes problems when `T` is not large enough.
To fix this, we make sure to add 1 to `T` if `ZEND_OBSERVER_ENABLED` is true.
Closes GH-16252.
Adding a stack check here as I consider serialization to be a more
sensitive place where erroring out with an exception seems appropriate.
Closes GH-16159.
zend_array_dup_ht_iterators() loops over the hash table iterators and
can call zend_hash_iterator_add(). zend_hash_iterator_add() can resize
the array causing a crash in zend_array_dup_ht_iterators().
We solve this by refetching the iter pointer after an add happened.
Closes GH-16060.
When allocating enough room for floats, the allocator used overflows with
large ndigits/EG(precision) value which used an signed integer to
increase the size of thebuffer.
Testing with the zend operator directly is enough to trigger
the issue rather than higher level math interface.
close GH-15715
`try` is a keyword in C++, and as such C++ code including <zend_enum.h>
fails to compile unless a workaround is in place. To resolve this, we
simply rename the parameter.
We choose `try_from` to make it clear that this parameter is true when
the function is called from `BackedEnum::tryFrom()`. For consistency,
we also rename the `try` parameter of `zend_enum_from_base()`, although
that function is not exported.
This issue had been reported by @oplanre, who also provided an initial
PR.
Closes GH-15259.
The destructor of generators is a no-op when the generator is running in a fiber,
because the fiber may resume the generator. Normally the destructor
is not called in this case, but this can happen during shutdown.
We detect that a generator is running in a fiber with the
ZEND_GENERATOR_IN_FIBER flag.
This change fixes two cases not handled by this mechanism:
- The ZEND_GENERATOR_IN_FIBER flag was not added when resuming a "yield from $nonGenerator"
- When a generator that is running in a fiber has multiple children (aka multiple generators yielding from it), all of them could be considered to also run in a fiber (only one actually is), and could leak if not destroyed before shutdown.
This prevents compilation error when compiling PHP by GCC with "-O2 -g -Wall -Werror"
zend_API.c:2754:34: error: array subscript ‘zend_function
{aka const union _zend_function}[0]’ is partly outside array bounds of
‘unsigned char[160]’ [-Werror=array-bounds=]
2754 | if (ZSTR_VAL(fptr->common.function_name)[0] != '_'
Instead of fixing up temporaries count in between observer steps, just apply the additional temporary in the two affected observer steps.
Closes GH-14018.
