From 2de18383f4e3cec85486259eb93b7652f60c6391 Mon Sep 17 00:00:00 2001
From: Robert Fancsik <frobert@inf.u-szeged.hu>
Date: Mon, 25 May 2020 16:08:55 +0200
Subject: [PATCH] Fix error handling in scanner when in case of OOM

This patch fixes #3786 and fixes #3788.

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik frobert@inf.u-szeged.hu
---
 jerry-core/parser/js/js-scanner-internal.h |  1 +
 jerry-core/parser/js/js-scanner-util.c     | 17 ++++++++++++
 jerry-core/parser/js/js-scanner.c          | 30 ++++++++++------------
 3 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/jerry-core/parser/js/js-scanner-internal.h b/jerry-core/parser/js/js-scanner-internal.h
index 3dbaf97a86..6214135cec 100644
--- a/jerry-core/parser/js/js-scanner-internal.h
+++ b/jerry-core/parser/js/js-scanner-internal.h
@@ -358,6 +358,7 @@ scanner_info_t *scanner_insert_info_before (parser_context_t *context_p, const u
                                             scanner_info_t *start_info_p, size_t size);
 scanner_literal_pool_t *scanner_push_literal_pool (parser_context_t *context_p, scanner_context_t *scanner_context_p,
                                                    uint16_t status_flags);
+void scanner_release_all_literal_pools (scanner_context_t *scanner_context_p);
 void scanner_pop_literal_pool (parser_context_t *context_p, scanner_context_t *scanner_context_p);
 #if ENABLED (JERRY_ES2015)
 void scanner_construct_global_block (parser_context_t *context_p, scanner_context_t *scanner_context_p);
diff --git a/jerry-core/parser/js/js-scanner-util.c b/jerry-core/parser/js/js-scanner-util.c
index f2d6235638..9386da922c 100644
--- a/jerry-core/parser/js/js-scanner-util.c
+++ b/jerry-core/parser/js/js-scanner-util.c
@@ -463,6 +463,23 @@ scanner_literal_is_arguments (lexer_lit_location_t *literal_p) /**< literal */
   return lexer_compare_identifier_to_string (literal_p, (const uint8_t *) "arguments", 9);
 } /* scanner_literal_is_arguments */
 
+/**
+ * Release all literal pools
+ */
+void
+scanner_release_all_literal_pools (scanner_context_t *scanner_context_p) /**< scanner context */
+{
+  while (scanner_context_p->active_literal_pool_p != NULL)
+  {
+    scanner_literal_pool_t *literal_pool_p = scanner_context_p->active_literal_pool_p;
+
+    scanner_context_p->active_literal_pool_p = literal_pool_p->prev_p;
+
+    parser_list_free (&literal_pool_p->literal_pool);
+    scanner_free (literal_pool_p, sizeof (scanner_literal_pool_t));
+  }
+} /* scanner_release_all_literal_pools */
+
 /**
  * Pop the last literal pool from the end.
  */
diff --git a/jerry-core/parser/js/js-scanner.c b/jerry-core/parser/js/js-scanner.c
index 45f643423b..ccb2a4fdcf 100644
--- a/jerry-core/parser/js/js-scanner.c
+++ b/jerry-core/parser/js/js-scanner.c
@@ -3159,12 +3159,6 @@ scanner_scan_all (parser_context_t *context_p, /**< context */
   }
   PARSER_CATCH
   {
-    /* Ignore the errors thrown by the lexer. */
-    if (context_p->error != PARSER_ERR_OUT_OF_MEMORY)
-    {
-      context_p->error = PARSER_ERR_NO_ERROR;
-    }
-
 #if ENABLED (JERRY_ES2015)
     while (scanner_context.active_binding_list_p != NULL)
     {
@@ -3172,6 +3166,16 @@ scanner_scan_all (parser_context_t *context_p, /**< context */
     }
 #endif /* ENABLED (JERRY_ES2015) */
 
+    if (JERRY_UNLIKELY (context_p->error == PARSER_ERR_OUT_OF_MEMORY))
+    {
+      scanner_release_all_literal_pools (&scanner_context);
+      parser_stack_free (context_p);
+      return;
+    }
+
+    /* Ignore the errors thrown by the lexer. */
+    context_p->error = PARSER_ERR_NO_ERROR;
+
     /* The following code may allocate memory, so it is enclosed in a try/catch. */
     PARSER_TRY (context_p->try_buffer)
     {
@@ -3193,17 +3197,11 @@ scanner_scan_all (parser_context_t *context_p, /**< context */
     }
     PARSER_CATCH
     {
-      JERRY_ASSERT (context_p->error == PARSER_ERR_NO_ERROR);
+      JERRY_ASSERT (context_p->error == PARSER_ERR_OUT_OF_MEMORY);
 
-      while (scanner_context.active_literal_pool_p != NULL)
-      {
-        scanner_literal_pool_t *literal_pool_p = scanner_context.active_literal_pool_p;
-
-        scanner_context.active_literal_pool_p = literal_pool_p->prev_p;
-
-        parser_list_free (&literal_pool_p->literal_pool);
-        scanner_free (literal_pool_p, sizeof (scanner_literal_pool_t));
-      }
+      scanner_release_all_literal_pools (&scanner_context);
+      parser_stack_free (context_p);
+      return;
     }
     PARSER_TRY_END