tsrm environment lock

diff --git a/TSRM/TSRM.c b/TSRM/TSRM.c
index 670c260678d426997cbb0b1179d1cf48850828d4..d70c09d2b529a9c617e572368f2d1620707a08b1 100644 (file)
--- a/TSRM/TSRM.c
+++ b/TSRM/TSRM.c
@@ -52,7 +52,8 @@ static int                                    resource_types_table_size;
 static size_t tsrm_reserved_pos  = 0;
 static size_t tsrm_reserved_size = 0;
 
-static MUTEX_T tsmm_mutex;     /* thread-safe memory manager mutex */
+static MUTEX_T tsmm_mutex;       /* thread-safe memory manager mutex */
+static MUTEX_T tsrm_env_mutex; /* tsrm environ mutex */
 
 /* New thread handlers */
 static tsrm_thread_begin_func_t tsrm_new_thread_begin_handler = NULL;
@@ -168,6 +169,8 @@ TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debu
        tsrm_reserved_pos  = 0;
        tsrm_reserved_size = 0;
 
+       tsrm_env_mutex = tsrm_mutex_alloc();
+
        return 1;
 }/*}}}*/
 
@@ -214,6 +217,8 @@ TSRM_API void tsrm_shutdown(void)
        }
        tsrm_mutex_free(tsmm_mutex);
        tsmm_mutex = NULL;
+       tsrm_mutex_free(tsrm_env_mutex);
+       tsrm_env_mutex = NULL;
        TSRM_ERROR((TSRM_ERROR_LEVEL_CORE, "Shutdown TSRM"));
        if (tsrm_error_file!=stderr) {
                fclose(tsrm_error_file);
@@ -237,6 +242,15 @@ TSRM_API void tsrm_shutdown(void)
        tsrm_reserved_size = 0;
 }/*}}}*/
 
+/* {{{ */
+/* environ lock api */
+TSRM_API int tsrm_env_lock() {
+    return tsrm_mutex_lock(tsrm_env_mutex);
+}
+
+TSRM_API int tsrm_env_unlock() {
+    return tsrm_mutex_unlock(tsrm_env_mutex);
+} /* }}} */
 
 /* enlarge the arrays for the already active threads */
 static void tsrm_update_active_threads(void)

diff --git a/TSRM/TSRM.h b/TSRM/TSRM.h
index a14e31e1f00e09fb80e81f1b71b3c87220fb19b1..5e1f8164ee79f542595b5cc18d1b579004af7820 100644 (file)
--- a/TSRM/TSRM.h
+++ b/TSRM/TSRM.h
@@ -99,6 +99,10 @@ extern "C" {
 TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debug_level, char *debug_filename);
 TSRM_API void tsrm_shutdown(void);
 
+/* environ lock API */
+TSRM_API int tsrm_env_lock();
+TSRM_API int tsrm_env_unlock();
+
 /* allocates a new thread-safe-resource id */
 TSRM_API ts_rsrc_id ts_allocate_id(ts_rsrc_id *rsrc_id, size_t size, ts_allocate_ctor ctor, ts_allocate_dtor dtor);
 
@@ -205,6 +209,9 @@ TSRM_API const char *tsrm_api_name(void);
 
 #else /* non ZTS */
 
+#define tsrm_env_lock()    0
+#define tsrm_env_unlock()  0
+
 #define TSRMLS_FETCH()
 #define TSRMLS_FETCH_FROM_CTX(ctx)
 #define TSRMLS_SET_CTX(ctx)

diff --git a/UPGRADING.INTERNALS b/UPGRADING.INTERNALS
index 626c71e6638c895c41774260faada909f2a0577b..aba4dc90cb2826c7c3fe414316752e23627f2d62 100644 (file)
--- a/UPGRADING.INTERNALS
+++ b/UPGRADING.INTERNALS
@@ -18,7 +18,8 @@ PHP 7.4 INTERNALS UPGRADE NOTES
   o. ZEND_COMPILE_EXTENDED_INFO split
   p. ZEND_EXT_FCALL_BEGIN can access arguments
   q. ZEND_COMPILE_IGNORE_USER_FUNCTIONS and ZEND_COMPILE_IGNORE_INTERNAL_FUNCTIONS
-
+  r. TSRM environment locking
+  
 2. Build system changes
   a. Abstract
   b. Unix build system changes
@@ -184,6 +185,19 @@ PHP 7.4 INTERNALS UPGRADE NOTES
      call opcodes are ZEND_DO_FCALL and ZEND_DO_FCALL_BY_NAME, previously they
      were ignored by zend_get_call_op.
      
+  r. TSRM adds tsrm_env_lock() and tsrm_env_unlock() for ZTS: 
+     code that may change environ and may run concurrently with user code in ZTS
+     is expected to use this exclusion API to maintain as much safety as reasonable.
+     This results in "thread safe" getenv/putenv in Windows and Unix, however 
+     functions that may read the environment without exclusion still exist,
+     for example:
+       - setlocale
+       - mktime
+       - tzset
+     The above is not an exhaustive list of such functions, while getenv/putenv will
+     behave as if they are safe, care should still be taken in multi-threaded
+     environments.
+     
 ========================
 2. Build system changes
 ========================

diff --git a/ext/standard/basic_functions.c b/ext/standard/basic_functions.c
index d281730afa3fd980bdf817e8e336c6b2ece974ea..ba4b5ee68cc458f2d383be47d68f3671e326088f 100644 (file)
--- a/ext/standard/basic_functions.c
+++ b/ext/standard/basic_functions.c
@@ -3832,7 +3832,9 @@ PHP_RSHUTDOWN_FUNCTION(basic) /* {{{ */
        ZVAL_UNDEF(&BG(strtok_zval));
        BG(strtok_string) = NULL;
 #ifdef HAVE_PUTENV
+       tsrm_env_lock();
        zend_hash_destroy(&BG(putenv_ht));
+       tsrm_env_unlock();
 #endif
 
        BG(mt_rand_is_seeded) = 0;
@@ -4141,11 +4143,22 @@ PHP_FUNCTION(getenv)
                }
        }
 #else
+
+    tsrm_env_lock();
+    
        /* system method returns a const */
        ptr = getenv(str);
+       
        if (ptr) {
-               RETURN_STRING(ptr);
+               RETVAL_STRING(ptr);
        }
+
+    tsrm_env_unlock();
+
+    if (ptr) {
+        return;
+    }
+
 #endif
        RETURN_FALSE;
 }
@@ -4196,6 +4209,7 @@ PHP_FUNCTION(putenv)
        }
 #endif
 
+       tsrm_env_lock();
        zend_hash_str_del(&BG(putenv_ht), pe.key, pe.key_len);
 
        /* find previous value */
@@ -4256,6 +4270,7 @@ PHP_FUNCTION(putenv)
                        tzset();
                }
 #endif
+               tsrm_env_unlock();
 #if defined(PHP_WIN32)
                free(keyw);
                free(valw);

diff --git a/ext/standard/info.c b/ext/standard/info.c
index 570c92393c73a24336335ee1f37884dcbc88ba1a..4600d66d1776a50d746889e95ba5483f071a9aeb 100644 (file)
--- a/ext/standard/info.c
+++ b/ext/standard/info.c
@@ -954,6 +954,7 @@ PHPAPI void php_print_info(int flag)
                SECTION("Environment");
                php_info_print_table_start();
                php_info_print_table_header(2, "Variable", "Value");
+               tsrm_env_lock();
                for (env=environ; env!=NULL && *env !=NULL; env++) {
                        tmp1 = estrdup(*env);
                        if (!(tmp2=strchr(tmp1,'='))) { /* malformed entry? */
@@ -965,6 +966,7 @@ PHPAPI void php_print_info(int flag)
                        php_info_print_table_row(2, tmp1, tmp2);
                        efree(tmp1);
                }
+        tsrm_env_unlock();
                php_info_print_table_end();
        }
 

diff --git a/main/php_variables.c b/main/php_variables.c
index decf73a80f659f699eb012a1ec75a05680a1df6e..f5692ede4bd0ebd68a62742a28b7e1e23dcffbaa 100644 (file)
--- a/main/php_variables.c
+++ b/main/php_variables.c
@@ -548,6 +548,8 @@ void _php_import_environment_variables(zval *array_ptr)
        zval val;
        zend_ulong idx;
 
+       tsrm_env_lock();
+
        for (env = environ; env != NULL && *env != NULL; env++) {
                p = strchr(*env, '=');
                if (!p
@@ -572,6 +574,8 @@ void _php_import_environment_variables(zval *array_ptr)
                        php_register_variable_quick(*env, name_len, &val, Z_ARRVAL_P(array_ptr));
                }
        }
+       
+       tsrm_env_unlock();
 }
 
 zend_bool php_std_auto_global_callback(char *name, uint32_t name_len)

diff --git a/sapi/litespeed/lsapi_main.c b/sapi/litespeed/lsapi_main.c
index 64e95d5cebf3523ce1ccdca0ec8adb4e601f8ff6..2d8eb7532658546af2948450ea94bf8845923814 100644 (file)
--- a/sapi/litespeed/lsapi_main.c
+++ b/sapi/litespeed/lsapi_main.c
@@ -244,6 +244,7 @@ static void litespeed_php_import_environment_variables(zval *array_ptr)
         return;
     }
 
+    tsrm_env_lock();
     for (env = environ; env != NULL && *env != NULL; env++) {
         p = strchr(*env, '=');
         if (!p) {               /* malformed entry? */
@@ -258,6 +259,7 @@ static void litespeed_php_import_environment_variables(zval *array_ptr)
         t[nlen] = '\0';
         add_variable(t, nlen, p + 1, strlen( p + 1 ), array_ptr);
     }
+    tsrm_env_unlock();
     if (t != buf && t != NULL) {
         efree(t);
     }