- Use ZEND_FREE() opcode instead of ZEND_SWITCH_FREE(IS_TMP_VAR)

- Fixed bug #44913 (Segfault when using return in combination with nested loops
and continue 2)

7 files changed, 73 insertions, 43 deletions

diff --git a/NEWS b/NEWS
index 25cacc7914..522a336229 100644
--- a/NEWS
+++ b/NEWS
@@ -109,6 +109,7 @@
 - Added Windows support for asinh(), acosh(), atanh(), log1p() and expm1() (Kalle)
 
 - Improved PHP runtime speed and memory usage:
+  . Use ZEND_FREE() opcode instead of ZEND_SWITCH_FREE(IS_TMP_VAR). (Dmitry)
   . Lazy EG(active_symbol_table) initialization. (Dmitry)
   . Optimized ZEND_RETURN opcode to not allocate and copy return value if it is
     not used. (Dmitry)
@@ -169,6 +170,8 @@
 - Fixed an issue in date() where a : was printed for the O modifier after a P
   modifier was used. (Derick)
 
+- Fixed bug #44913 (Segfault when using return in combination with nested loops
+  and continue 2). (Dmitry)
 - Fixed bug #44899 (__isset usage changes behavior of empty()) (Etienne)
 - Fixed bug #44805 (rename() function is not portable to Windows). (Pierre)
 - Fixed bug #44742 (timezone_offset_get() causes segmentation faults). (Derick)
diff --git a/Zend/tests/bug44913.phpt b/Zend/tests/bug44913.phpt
new file mode 100644
index 0000000000..0c2551fb04
--- /dev/null
+++ b/Zend/tests/bug44913.phpt
@@ -0,0 +1,17 @@
+--TEST--
+Bug #44913 (Segfault when using return in combination with nested loops and continue 2)
+--FILE--
+<?php
+function something() {
+        foreach(array(1, 2) as $value) {
+                for($i = 0; $i < 1; $i++) {
+                        continue 2;
+                }
+                return;
+        }
+}
+something();
+echo "ok\n";
+?>
+--EXPECT--
+ok
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 09bf537156..8b3b15af4b 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -2024,7 +2024,7 @@ static int generate_free_switch_expr(zend_switch_entry *switch_entry TSRMLS_DC)
 
 	opline = get_next_op(CG(active_op_array) TSRMLS_CC);
 
-	opline->opcode = ZEND_SWITCH_FREE;
+	opline->opcode = (switch_entry->cond.op_type == IS_TMP_VAR) ? ZEND_FREE : ZEND_SWITCH_FREE;
 	opline->op1 = switch_entry->cond;
 	SET_UNUSED(opline->op2);
 	opline->extended_value = 0;
@@ -2042,7 +2042,7 @@ static int generate_free_foreach_copy(zend_op *foreach_copy TSRMLS_DC)
 
 	opline = get_next_op(CG(active_op_array) TSRMLS_CC);
 
-	opline->opcode = ZEND_SWITCH_FREE;
+	opline->opcode = (foreach_copy->result.op_type == IS_TMP_VAR) ? ZEND_FREE : ZEND_SWITCH_FREE;
 	opline->op1 = foreach_copy->result;
 	SET_UNUSED(opline->op2);
 	opline->extended_value = 1;
@@ -2050,7 +2050,7 @@ static int generate_free_foreach_copy(zend_op *foreach_copy TSRMLS_DC)
 	if (foreach_copy->op1.op_type != IS_UNUSED) {
 		opline = get_next_op(CG(active_op_array) TSRMLS_CC);
 
-		opline->opcode = ZEND_SWITCH_FREE;
+		opline->opcode = (foreach_copy->op1.op_type == IS_TMP_VAR) ? ZEND_FREE : ZEND_SWITCH_FREE;
 		opline->op1 = foreach_copy->op1;
 		SET_UNUSED(opline->op2);
 		opline->extended_value = 0;
@@ -2062,6 +2062,7 @@ static int generate_free_foreach_copy(zend_op *foreach_copy TSRMLS_DC)
 void zend_do_return(znode *expr, int do_end_vparse TSRMLS_DC)
 {
 	zend_op *opline;
+	int start_op_number, end_op_number;
 
 	if (do_end_vparse) {
 		if (CG(active_op_array)->return_reference && !zend_is_function_or_method_call(expr)) {
@@ -2071,6 +2072,8 @@ void zend_do_return(znode *expr, int do_end_vparse TSRMLS_DC)
 		}
 	}
 
+	start_op_number = get_next_op_number(CG(active_op_array));
+
 #ifdef ZTS
 	zend_stack_apply_with_argument(&CG(switch_cond_stack), ZEND_STACK_APPLY_TOPDOWN, (int (*)(void *element, void *)) generate_free_switch_expr TSRMLS_CC);
 	zend_stack_apply_with_argument(&CG(foreach_copy_stack), ZEND_STACK_APPLY_TOPDOWN, (int (*)(void *element, void *)) generate_free_foreach_copy TSRMLS_CC);
@@ -2079,6 +2082,12 @@ void zend_do_return(znode *expr, int do_end_vparse TSRMLS_DC)
 	zend_stack_apply(&CG(foreach_copy_stack), ZEND_STACK_APPLY_TOPDOWN, (int (*)(void *element)) generate_free_foreach_copy);
 #endif
 
+	end_op_number = get_next_op_number(CG(active_op_array));
+	while (start_op_number < end_op_number) {
+		CG(active_op_array)->opcodes[start_op_number].op1.u.EA.type = EXT_TYPE_FREE_ON_RETURN;
+		start_op_number++;
+	}
+
 	opline = get_next_op(CG(active_op_array) TSRMLS_CC);
 
 	opline->opcode = ZEND_RETURN;
@@ -3075,7 +3084,7 @@ void zend_do_switch_end(znode *case_list TSRMLS_DC)
 	if (switch_entry_ptr->cond.op_type==IS_VAR || switch_entry_ptr->cond.op_type==IS_TMP_VAR) {
 		/* emit free for the switch condition*/
 		opline = get_next_op(CG(active_op_array) TSRMLS_CC);
-		opline->opcode = ZEND_SWITCH_FREE;
+		opline->opcode = (switch_entry_ptr->cond.op_type == IS_TMP_VAR) ? ZEND_FREE : ZEND_SWITCH_FREE;
 		opline->op1 = switch_entry_ptr->cond;
 		SET_UNUSED(opline->op2);
 	}
diff --git a/Zend/zend_compile.h b/Zend/zend_compile.h
index 8e06da218a..e6340d9dde 100644
--- a/Zend/zend_compile.h
+++ b/Zend/zend_compile.h
@@ -323,7 +323,8 @@ struct _zend_execute_data {
 #define IS_UNUSED	(1<<3)	/* Unused variable */
 #define IS_CV		(1<<4)	/* Compiled variable */
 
-#define EXT_TYPE_UNUSED		(1<<0)
+#define EXT_TYPE_UNUSED				(1<<0)
+#define EXT_TYPE_FREE_ON_RETURN		(2<<0)
 
 #include "zend_globals.h"
 
diff --git a/Zend/zend_execute.c b/Zend/zend_execute.c
index 2391fc08cc..bf8884907c 100644
--- a/Zend/zend_execute.c
+++ b/Zend/zend_execute.c
@@ -377,22 +377,18 @@ static inline zval *_get_obj_zval_ptr(znode *op, temp_variable *Ts, zend_free_op
 	return get_zval_ptr(op, Ts, should_free, type);
 }
 
-static inline void zend_switch_free(temp_variable *T, int type, int extended_value TSRMLS_DC)
+static inline void zend_switch_free(temp_variable *T, int extended_value TSRMLS_DC)
 {
-	if (type == IS_VAR) {
-		if (T->var.ptr) {
-			if (extended_value & ZEND_FE_RESET_VARIABLE) { /* foreach() free */
-				Z_DELREF_P(T->var.ptr);
-			}
-			zval_ptr_dtor(&T->var.ptr);
-		} else if (!T->var.ptr_ptr) {
-			/* perform the equivalent of equivalent of a
-			 * quick & silent get_zval_ptr, and FREE_OP
-			 */
-			PZVAL_UNLOCK_FREE(T->str_offset.str);
+	if (T->var.ptr) {
+		if (extended_value & ZEND_FE_RESET_VARIABLE) { /* foreach() free */
+			Z_DELREF_P(T->var.ptr);
 		}
-	} else { /* IS_TMP_VAR */
-		zendi_zval_dtor(T->tmp_var);
+		zval_ptr_dtor(&T->var.ptr);
+	} else if (!T->var.ptr_ptr) {
+		/* perform the equivalent of equivalent of a
+		 * quick & silent get_zval_ptr, and FREE_OP
+		 */
+		PZVAL_UNLOCK_FREE(T->str_offset.str);
 	}
 }
 
@@ -1241,10 +1237,14 @@ static inline zend_brk_cont_element* zend_brk_cont(zval *nest_levels_zval, int a
 
 			switch (brk_opline->opcode) {
 				case ZEND_SWITCH_FREE:
-					zend_switch_free(&T(brk_opline->op1.u.var), brk_opline->op1.op_type, brk_opline->extended_value TSRMLS_CC);
+					if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+						zend_switch_free(&T(brk_opline->op1.u.var), brk_opline->extended_value TSRMLS_CC);
+					}
 					break;
 				case ZEND_FREE:
-					zendi_zval_dtor(T(brk_opline->op1.u.var).tmp_var);
+					if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+						zendi_zval_dtor(T(brk_opline->op1.u.var).tmp_var);
+					}
 					break;
 			}
 		}
diff --git a/Zend/zend_vm_def.h b/Zend/zend_vm_def.h
index bbe1ee6b4c..df2d6e2665 100644
--- a/Zend/zend_vm_def.h
+++ b/Zend/zend_vm_def.h
@@ -2642,10 +2642,14 @@ ZEND_VM_HANDLER(100, ZEND_GOTO, ANY, CONST)
 
 	switch (brk_opline->opcode) {
 		case ZEND_SWITCH_FREE:
-			zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->op1.op_type, brk_opline->extended_value TSRMLS_CC);
+			if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+				zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->extended_value TSRMLS_CC);
+			}
 			break;
 		case ZEND_FREE:
-			zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
+			if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+				zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
+			}
 			break;
 	}
 	ZEND_VM_JMP(opline->op1.u.jmp_addr);
@@ -2683,11 +2687,11 @@ ZEND_VM_HANDLER(48, ZEND_CASE, CONST|TMP|VAR|CV, CONST|TMP|VAR|CV)
 	ZEND_VM_NEXT_OPCODE();
 }
 
-ZEND_VM_HANDLER(49, ZEND_SWITCH_FREE, TMP|VAR, ANY)
+ZEND_VM_HANDLER(49, ZEND_SWITCH_FREE, VAR, ANY)
 {
 	zend_op *opline = EX(opline);
 
-	zend_switch_free(&EX_T(opline->op1.u.var), OP1_TYPE, opline->extended_value TSRMLS_CC);
+	zend_switch_free(&EX_T(opline->op1.u.var), opline->extended_value TSRMLS_CC);
 	ZEND_VM_NEXT_OPCODE();
 }
 
@@ -4123,10 +4127,14 @@ ZEND_VM_HANDLER(149, ZEND_HANDLE_EXCEPTION, ANY, ANY)
 
 				switch (brk_opline->opcode) {
 					case ZEND_SWITCH_FREE:
-						zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->op1.op_type, brk_opline->extended_value TSRMLS_CC);
+						if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+							zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->extended_value TSRMLS_CC);
+						}
 						break;
 					case ZEND_FREE:
-						zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
+						if (brk_opline->op1.u.EA.type != EXT_TYPE_FREE_ON_RETURN) {
+							zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
+						}
 						break;
 				}
 			}
diff --git a/Zend/zend_vm_execute.h b/Zend/zend_vm_execute.h
index 0d29a570d7..e23f8d344a 100644
--- a/Zend/zend_vm_execute.h
+++ b/Zend/zend_vm_execute.h
@@ -515,7 +515,7 @@ static int ZEND_HANDLE_EXCEPTION_SPEC_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 
 				switch (brk_opline->opcode) {
 					case ZEND_SWITCH_FREE:
-						zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->op1.op_type, brk_opline->extended_value TSRMLS_CC);
+						zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->extended_value TSRMLS_CC);
 						break;
 					case ZEND_FREE:
 						zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
@@ -724,7 +724,7 @@ static int ZEND_GOTO_SPEC_CONST_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 
 	switch (brk_opline->opcode) {
 		case ZEND_SWITCH_FREE:
-			zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->op1.op_type, brk_opline->extended_value TSRMLS_CC);
+			zend_switch_free(&EX_T(brk_opline->op1.u.var), brk_opline->extended_value TSRMLS_CC);
 			break;
 		case ZEND_FREE:
 			zendi_zval_dtor(EX_T(brk_opline->op1.u.var).tmp_var);
@@ -4735,14 +4735,6 @@ static int ZEND_BOOL_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 	ZEND_VM_NEXT_OPCODE();
 }
 
-static int ZEND_SWITCH_FREE_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
-{
-	zend_op *opline = EX(opline);
-
-	zend_switch_free(&EX_T(opline->op1.u.var), IS_TMP_VAR, opline->extended_value TSRMLS_CC);
-	ZEND_VM_NEXT_OPCODE();
-}
-
 static int ZEND_CLONE_SPEC_TMP_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 {
 	zend_op *opline = EX(opline);
@@ -7990,7 +7982,7 @@ static int ZEND_SWITCH_FREE_SPEC_VAR_HANDLER(ZEND_OPCODE_HANDLER_ARGS)
 {
 	zend_op *opline = EX(opline);
 
-	zend_switch_free(&EX_T(opline->op1.u.var), IS_VAR, opline->extended_value TSRMLS_CC);
+	zend_switch_free(&EX_T(opline->op1.u.var), opline->extended_value TSRMLS_CC);
 	ZEND_VM_NEXT_OPCODE();
 }
 
@@ -30747,11 +30739,11 @@ void zend_init_opcodes_handlers(void)
   	ZEND_NULL_HANDLER,
   	ZEND_NULL_HANDLER,
   	ZEND_NULL_HANDLER,
-  	ZEND_SWITCH_FREE_SPEC_TMP_HANDLER,
-  	ZEND_SWITCH_FREE_SPEC_TMP_HANDLER,
-  	ZEND_SWITCH_FREE_SPEC_TMP_HANDLER,
-  	ZEND_SWITCH_FREE_SPEC_TMP_HANDLER,
-  	ZEND_SWITCH_FREE_SPEC_TMP_HANDLER,
+  	ZEND_NULL_HANDLER,
+  	ZEND_NULL_HANDLER,
+  	ZEND_NULL_HANDLER,
+  	ZEND_NULL_HANDLER,
+  	ZEND_NULL_HANDLER,
   	ZEND_SWITCH_FREE_SPEC_VAR_HANDLER,
   	ZEND_SWITCH_FREE_SPEC_VAR_HANDLER,
   	ZEND_SWITCH_FREE_SPEC_VAR_HANDLER,