Verified Commit 9022c51d authored by James Teh's avatar James Teh Committed by ma1
Browse files

Bug 2052562: Don't allow moves into a detached subtree. a=pascalc 

Original Revision: https://phabricator.services.mozilla.com/D310457

Differential Revision: https://phabricator.services.mozilla.com/D311752
parent d35af1a8

accessible/ipc/DocAccessibleParent.cpp

+22 −11
Original line number Diff line number Diff line
@@ -141,6 +141,16 @@ mozilla::ipc::IPCResult DocAccessibleParent::ProcessShowEvent( 
      // This is the first Accessible, which is the root of the shown subtree.

      root = child;

      rootParent = parent;

      if (!aComplete) {

        // This is the first message for a show event split across multiple

        // messages. Save the show target for subsequent messages and return.

        mPendingShowChild = accData.ID();

        mPendingShowParent = accData.ParentID();

        mPendingShowIndex = accData.IndexInParent();

        if (!rootParent->IsDoc() && !rootParent->RemoteParent()) {

          return IPC_FAIL(this, "Attempt to split show with detached root");

        }

      }

    }

    // If this show event has been split across multiple messages and this is

    // not the last message, don't attach the shown root to the tree yet.
@@ -155,21 +165,11 @@ mozilla::ipc::IPCResult DocAccessibleParent::ProcessShowEvent( 


  MOZ_ASSERT(CheckDocTree());



  if (!aComplete && !mPendingShowChild) {

    // This is the first message for a show event split across multiple

    // messages. Save the show target for subsequent messages and return.

    const auto& accData = aNewTree[0];

    mPendingShowChild = accData.ID();

    mPendingShowParent = accData.ParentID();

    mPendingShowIndex = accData.IndexInParent();

    return IPC_OK();

  }

  if (!aComplete) {

    // This show event has been split into multiple messages, but this is

    // neither the first nor the last message. There's nothing more to do here.

    // not the last message. There's nothing more to do here.

    return IPC_OK();

  }

  MOZ_ASSERT(aComplete);

  if (mPendingShowChild) {

    // This is the last message for a show event split across multiple

    // messages. Retrieve the saved show target, attach it to the tree and fire
@@ -242,6 +242,8 @@ RemoteAccessible* DocAccessibleParent::CreateAcc( 
          "Attempt to move RemoteAccessible which has a pending parent");

      return nullptr;

    }

    MOZ_RELEASE_ASSERT(newProxy->ChildCount() == 0 || newProxy->IsOuterDoc(),

                       "Reused RemoteAccessible unexpectedly has children!");

    return newProxy;

  }
@@ -293,6 +295,15 @@ bool DocAccessibleParent::AttachChild(RemoteAccessible* aParent, 
    return false;

  }



  if (!aParent->IsDoc() && !aParent->RemoteParent() &&

      aParent->ID() != mPendingShowChild) {

    MOZ_ASSERT_UNREACHABLE("Attempt to attach child to a detached parent!");

    return false;

  }



  MOZ_RELEASE_ASSERT(!mPendingShowChild || aChild->ID() != mPendingShowParent,

                     "Attempt to attach the pending show's parent as a child!");



  if (aParent == aChild) {

    MOZ_ASSERT_UNREACHABLE("Attempt to make an accessible its own child!");

    return false;