[inspector] fix sourceURL magic comment parsing

R=szuend@chromium.org

Fixed: chromium:1078205
Change-Id: I16f8e19a249692fd16fd53a9a56a8f4cfed8b5c0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2185134
Auto-Submit: Yang Guo <yangguo@chromium.org>
Commit-Queue: Simon Zünd <szuend@chromium.org>
Reviewed-by: Simon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67634}

src/inspector/search-util.cc

@@ -36,7 +36,8 @@ String16 findMagicComment(const String16& content, const String16& name,
     if (content[pos + 2] != '#' && content[pos + 2] != '@') continue;
     if (content[pos + 3] != ' ' && content[pos + 3] != '\t') continue;
     equalSignPos = pos + 4 + nameLength;
-    if (equalSignPos < length && content[equalSignPos] != '=') continue;
+    if (equalSignPos >= length) continue;
+    if (content[equalSignPos] != '=') continue;
     if (multiline) {
       closingCommentPos = content.find("*/", equalSignPos + 1);
       if (closingCommentPos == String16::kNotFound) return String16();
@@ -46,6 +47,7 @@ String16 findMagicComment(const String16& content, const String16& name,
   }
 
   DCHECK(equalSignPos);
+  DCHECK_LT(equalSignPos, length);
   DCHECK(!multiline || closingCommentPos);
   size_t urlPos = equalSignPos + 1;
   String16 match = multiline

test/inspector/runtime/regress-1078205-expected.txt

+Test malformed sourceURL magic comment.
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}
+{
+    id : <messageId>
+    result : {
+        exceptionDetails : {
+            columnNumber : 0
+            exception : {
+                className : SyntaxError
+                description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+                objectId : <objectId>
+                subtype : error
+                type : object
+            }
+            exceptionId : <exceptionId>
+            lineNumber : 0
+            scriptId : <scriptId>
+            text : Uncaught
+        }
+        result : {
+            className : SyntaxError
+            description : SyntaxError: Unexpected token / in JSON at position 0     at JSON.parse (<anonymous>)     at <anonymous>:1:6
+            objectId : <objectId>
+            subtype : error
+            type : object
+        }
+    }
+}

test/inspector/runtime/regress-1078205.js

+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+let {session, contextGroup, Protocol} = InspectorTest.start(
+    'Test malformed sourceURL magic comment.');
+
+(async function test() {
+  await Protocol.Debugger.enable();
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//')",
+    generatePreview: true,
+  }));
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//#')",
+    generatePreview: true,
+  }));
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//# ')",
+    generatePreview: true,
+  }));
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//# sourceURL')",
+    generatePreview: true,
+  }));
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//# sourceURL=')",
+    generatePreview: true,
+  }));
+  InspectorTest.logMessage(await Protocol.Runtime.evaluate({
+    expression: "JSON.parse('//# sourceURL=\"')",
+    generatePreview: true,
+  }));
+  InspectorTest.completeTest();
+})();