Add a C function, opcache_preloading(), that returns true during
preloading. Extensions can use this to detect preloading, not only during
compilation/execution, but also in RINIT()/RSHUTDOWN().
Since opcache currently doesn't install any header, I'm adding a new one:
zend_accelerator_api.h. Header name is based on other files in ext/opcache.
Closes GH-19288
Avoid initializing the same string content multiple times and make use of the
fact that the strings created to initialize attribute values are not freed by
simply making use of an existing zend_string with the same content if one is
available.
Instead of
* adding a zval on the stack
* initializing it
* copying the value to the attribute
Just initialize the value directly in the zend_attribute_arg
* PHP-8.4:
pdo_odbc: Fix memory leak if WideCharToMultiByte() fails
Fix memory leak on php_odbc_fetch_hash() failure
Do not delete main chunk in zend_gc
* PHP-8.3:
pdo_odbc: Fix memory leak if WideCharToMultiByte() fails
Fix memory leak on php_odbc_fetch_hash() failure
Do not delete main chunk in zend_gc
Update to PHP-Parser 5.5.0 and add support for attributes on constants in
stubs. For now, I have only migrated over E_STRICT, once the support is in
place I'll do a larger migration of the existing deprecated constants.
In the process, fix the logic in `copy_zend_constant()` for copying attributes
when a constant is copied; just increase the reference count for the attributes
table rather than trying to duplicate the contents.
Debugging memory corruption issues in production can be difficult when it's not possible to use a debug build or ASAN/MSAN/Valgrind (e.g. for performance reasons).
This change makes it possible to enable some basic heap debugging helpers without rebuilding PHP. This is controlled by the environment variable ZEND_MM_DEBUG. The env var takes a comma-separated list of parameters:
- poison_free=byte: Override freed blocks with the specified byte value (represented as a number)
- poison_alloc=byte: Override newly allocated blocks with the specified byte value (represented as a number)
- padding=bytes: Pad allocated blocks with the specified amount of bytes (if non-zero, a value >= 16 is recommended to not break alignments)
- check_freelists_on_shutdown=0|1: Enable checking freelist consistency [1] on shutdown
Example:
ZEND_MM_DEBUG=poison_free=0xbe,poison_alloc=0xeb,padding=16,check_freelists_on_shutdown=1 php ...
This is implemented by installing custom handlers when ZEND_MM_DEBUG is set.
This has zero overhead when ZEND_MM_DEBUG is not set. When ZEND_MM_DEBUG is set, the overhead is about 8.5% on the Symfony Demo benchmark.
Goals:
- Crash earlier after a memory corruption, to extract a useful backtrace
- Be usable in production with reasonable overhead
- Having zero overhead when not enabled
Non-goals:
- Replace debug builds, valgrind, ASAN, MSAN or other sanitizers
[1] https://github.com/php/php-src/pull/14054
Co-authored-by: Tim Düsterhus <timwolla@googlemail.com>
`zend_test_create_throwing_resource` sets the exception in the `test`
call frame and unwinds to `main`. It then throws for the `resource`
variable and verifies that the exception opline is set. However, it
wasn't set in `main`, it was set at the `test` call frame and rethrown later.
The assertion is too conservative, but the end result is right, so drop
the assertion.
Closes GH-17533.
Co-authored-by: Ilija Tovilo <ilija.tovilo@me.com>
The FFI call return values follow widening rules.
We must widen to `ffi_arg` in the case we're handling a return value for types shorter than the machine width.
From http://www.chiark.greenend.org.uk/doc/libffi-dev/html/The-Closure-API.html:
> In most cases, ret points to an object of exactly the size of the type specified when cif was constructed.
> However, integral types narrower than the system register size are widened.
> In these cases your program may assume that ret points to an ffi_arg object.
If we don't do this, we get wrong values when reading the return values.
Closes GH-17255.
Co-authored-by: Dmitry Stogov <dmitry@zend.com>
This testing code was never meant to be used this way, but fixing this
will at least stop fuzzers from complaining about this, so might still
be worthwhile.
Closes GH-16919.
