Fix crash when filter callback unsets StreamBucket::$data - #23466
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stream_bucket_prepend()/append() assumed a successful zend_read_property() of StreamBucket::$data always yields a string, but for an unset typed property it throws while returning &EG(uninitialized_zval), so Z_STRLEN_P() dereferenced a NULL string pointer and crashed when the brigade was consumed. Reject non-string reads up front (rethrowing any pending exception) so the bucket is never re-attached with undefined data; the sibling $bucket property path is already safe because zend_fetch_resource_ex() rejects non-resources.
NickSdot
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Aug 26, 2026
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| } catch (Error $e) { | ||
| printf("%s: %s\n", get_class($e), $e->getMessage()); | ||
| } |
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| } catch (Error $e) { | |
| printf("%s: %s\n", get_class($e), $e->getMessage()); | |
| } | |
| } catch (Throwable $e) { | |
| echo $e::class, ': ', $e->getMessage()); | |
| } |
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stream_bucket_prepend() and stream_bucket_append() assumed a successful zend_read_property() of StreamBucket::$data always yields a string, but when the property has been unset in the filter callback the read throws while returning &EG(uninitialized_zval), so Z_STRLEN_P() dereferenced a NULL string pointer and crashed once the brigade was consumed. Non-string reads are now rejected up front with the pending exception rethrown, so a bucket is never re-attached with undefined data; the sibling $bucket property path is already safe because zend_fetch_resource_ex() rejects non-resources.