Changeset 287048 in webkit

Timestamp:

Dec 14, 2021, 2:15:49 PM (5 years ago)

Author:

commit-queue@webkit.org

Message:

Adhere to DisplayList iterator's API contract in MemoryDisplayList::~InMemoryDisplayList()
​https://bugs.webkit.org/show_bug.cgi?id=234264

Patch by Gabriel Nava Marino <​gnavamarino@apple.com> on 2021-12-14
Reviewed by Myles C. Maxfield.

The client is not adhearing to the DisplayList Iterator's API contract in MemoryDisplayList::~InMemoryDisplayList():
"Part of the iterator's API contract is that if the item is nullopt, you're not allowed to keep
iterating - doing this will lead to an infinite loop."

Here we now do so by breaking out of iteration if the item is nullopt.

• platform/graphics/displaylists/InMemoryDisplayList.cpp:

(WebCore::DisplayList::InMemoryDisplayList::~InMemoryDisplayList):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/displaylists/InMemoryDisplayList.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2021-12-14  Gabriel Nava Marino  <gnavamarino@apple.com>
+
+        Adhere to DisplayList iterator's API contract in MemoryDisplayList::~InMemoryDisplayList()
+        https://bugs.webkit.org/show_bug.cgi?id=234264
+
+        Reviewed by Myles C. Maxfield.
+
+        The client is not adhearing to the DisplayList Iterator's API contract in MemoryDisplayList::~InMemoryDisplayList():
+        "Part of the iterator's API contract is that if the item is nullopt, you're not allowed to keep
+        iterating - doing this will lead to an infinite loop."
+
+        Here we now do so by breaking out of iteration if the item is nullopt.
+
+        * platform/graphics/displaylists/InMemoryDisplayList.cpp:
+        (WebCore::DisplayList::InMemoryDisplayList::~InMemoryDisplayList):
+
 2021-12-14  Alan Bujtas  <zalan@apple.com>
 

trunk/Source/WebCore/platform/graphics/displaylists/InMemoryDisplayList.cpp

@@ -64 +64 @@
     auto end = this->end();
     for (auto displayListItem : *this) {
+        if (!displayListItem)
+            break;
         auto item = displayListItem->item;
         ASSERT(item);