ext/ldap: fix crash in ldap_exop_sync() when $response_data is omitted - #23339
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lacatoire wants to merge 1 commit into
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ext/ldap: fix crash in ldap_exop_sync() when $response_data is omitted#23339lacatoire wants to merge 1 commit into
lacatoire wants to merge 1 commit into
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ldap_exop_sync() always takes the synchronous branch of php_ldap_exop(), which assigns $response_data unconditionally. When the argument is not passed, retdata is NULL and ZEND_TRY_ASSIGN_REF_STRINGL()/ ZEND_TRY_ASSIGN_REF_EMPTY_STRING() dereference it, so any successful ldap_exop_sync($ldap, $oid) call segfaults. Guard the assignment the way the $response_oid one already is.
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ldap_exop_sync()passesforce_sync = truetophp_ldap_exop(), so the block that writes back$response_datais always entered regardless of whether the argument was supplied. When it is omitted,retdataisNULL, and bothZEND_TRY_ASSIGN_REF_STRINGLandZEND_TRY_ASSIGN_REF_EMPTY_STRINGdereference it —ZEND_ASSERT(Z_ISREF_P(zv))in debug builds, a NULL dereference crash in release.ldap_exop()is not affected: thereretdata != NULLis what selects the branch in the first place.The fix mirrors the existing
if (retoid)guard a few lines above.ldap_memfree()is still called unconditionally so there is no memory leak.Reproduced on PHP 8.4.22 (exit code 139). Present since
ldap_exop_sync()was introduced in PHP 8.3.0.