This adds more aggressive clearing of stat cache. It is added to the
filestat as well as plain wrapper operations which covers stream file
accessing as well as exec functions (using pipes). It should hopefully
fix the most visible issues with the stat cache.
Closes GH-17681
`glob(3)` doesn't know the virtual CWD of PHP, so we need to pass an
absolute path for ZTS builds. In lack of a reusable routine, we copy
the code from `glob()` and adapt as needed.
Closes GH-17074.
We need to avoid signed integer overflows which are undefined behavior.
We catch that, and set `offset` to `ZEND_LONG_MAX` (which is also the
largest value of `zend_off_t` on all platforms). Of course, that seek
may fail, but even if it succeeds, the stream is no longer readable,
but that matches the current behavior for offsets near `ZEND_LONG_MAX`.
Closes GH-15989.
We need to avoid signed integer overflows which are undefined behavior.
We catch that, and set `offset` to `ZEND_LONG_MAX` (which is also the
largest value of `zend_off_t` on all platforms). Of course, after such
a seek a stream is no longer readable, but that matches the current
behavior for offsets near `ZEND_LONG_MAX`.
Closes GH-15989.
This was first reported as a leak in GH-15026, but was mistakingly
believed to be a false positive. Then an assertion was added and it got
triggered in GH-15908. This fixes the leak. Upon merging into master the
assertion should be removed as well.
Closes GH-15924.
We're reasonably sure that appending the NUL is not an OOB write, since
the memory stream implementation uses `zend_string` APIs instead of
fiddling with the buffer.
We don't add a regression test because that would require to set up
something in the zend_test extension, and regressions are supposed
to be caught by external consumers of this API, such as mailparse.
Closes GH-15648.
Although the issue was demonstrated using Curl, the issue is purely in
the streams layer of PHP.
Full analysis is written in GH-11078 [1], but here is the brief version:
Here's what actually happens:
1) We're creating a FILE handle from a stream using the casting mechanism.
This will create a cookie-based FILE handle using funopen.
2) We're reading stream data using fread from the userspace stream. This will
temporarily set a buffer into a field _bf.base [2]. This buffer is now equal
to the upload buffer that Curl allocated and note that that buffer is owned
by Curl.
3) The fatal error occurs and we bail out from the fread function, notice how
the reset code is never executed and so the buffer will still point to
Curl's upload buffer instead of FILE's own buffer [3].
4) The resources are destroyed, this includes our opened stream and because the
FILE handle is cached, it gets destroyed as well.
In fact, the stream code calls through fclose on purpose in this case.
5) The fclose code frees the _bs.base buffer [4].
However, this is not the buffer that FILE owns but the one that Curl owns
because it isn't reset properly due to the bailout!
6) The objects are getting destroyed, and so the curl free logic is invoked.
When Curl tries to gracefully clean up, it tries to free the buffer.
But that buffer is actually already freed mistakingly by the C library!
This also explains why we can't reproduce it on Linux: this bizarre buffer
swapping only happens on macOS and BSD, not on Linux.
To solve this, we switch to an unbuffered mode for cookie-based FILEs.
This avoids any stateful problems related to buffers especially when the
bailout mechanism triggers. As streams have their own buffering
mechanism, I don't expect this to impact performance.
[1] https://github.com/php/php-src/issues/11078#issuecomment-2155616843
[2] https://github.com/apple-open-source-mirror/Libc/blob/5e566be7a7047360adfb35ffc44c6a019a854bea/stdio/FreeBSD/fread.c#L102-L103
[3] https://github.com/apple-open-source-mirror/Libc/blob/5e566be7a7047360adfb35ffc44c6a019a854bea/stdio/FreeBSD/fread.c#L117
[4] https://github.com/apple-open-source-mirror/Libc/blob/5e566be7a7047360adfb35ffc44c6a019a854bea/stdio/FreeBSD/fclose.c#L66-L67
Closes GH-14524.
Commit 5cbe5a538c disabled chunking for all writes to streams. However,
user streams have a callback where code is executed on data that is
subject to the memory limit. Therefore, when using large writes or
stream_copy_to_stream/copy the memory limit can easily be hit with large
enough data.
To solve this, we reintroduce chunking for userspace streams.
Users have control over the chunk size, which is neat because
they can improve the performance by setting the chunk size if
that turns out to be a bottleneck.
In an ideal world, we add an option so we can "ask" the stream whether
it "prefers" chunked writes, similar to how we have
php_stream_mmap_supported & friends. However, that cannot be done on
stable branches.
Closes GH-13136.
This changes memory stream to allow seeking past end which makes it the
same as seeking on files. It means the position is allowed to be higher
than the string length. The size only increases if data is appended to
the past position. The space between the previous string and position
is filled with zero bytes.
Fixes GH-9441
Closes GH-12058
This is an alternative implementation for GH-10406 that resets the
has_buffered_data flag after finishing stream read so it does not impact
other ops->read use like for example php_stream_get_line.
Closes GH-11421
This adds support for the completed event. Since the read handler could
be entered twice towards the end of the stream we remember what the eof
flag was before reading so we can emit the completed event when the flag
changes to true.
Closes GH-10505.
| 732 | ts->mode = mode && mode[0] == 'r' && mode[1] != '+' ? TEMP_STREAM_READONLY : 0;
| | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
Although mode is already dereference on line 723 in the call to strlen()
This change restores the old behaviour for the server socket streams
that don't support IO. This is now stored in the stream flags so it can
be later used to do some other decisions and possibly introduce some
better error reporting.
Closes GH-10877
Jakub Zelenka