Last Comment Bug 705344 - Use IDL for Components.(utils.)lookupMethod
: Use IDL for Components.(utils.)lookupMethod
Product: Core
Classification: Components
Component: XPConnect (show other bugs)
: Trunk
: All All
: -- normal (vote)
: mozilla11
Assigned To: :Ms2ger
Depends on:
Blocks: 705324
  Show dependency treegraph
Reported: 2011-11-25 11:24 PST by :Ms2ger
Modified: 2011-12-18 07:12 PST (History)
2 users (show)
See Also:
Crash Signature:
QA Whiteboard:
Iteration: ---
Points: ---
Has Regression Range: ---
Has STR: ---

Patch v1 (9.45 KB, patch)
2011-11-25 11:24 PST, :Ms2ger
bobbyholley: review+
Details | Diff | Review

Description :Ms2ger 2011-11-25 11:24:03 PST
Created attachment 576974 [details] [diff] [review]
Patch v1
Comment 1 Andreas Gal :gal 2011-11-25 11:28:12 PST
Comment on attachment 576974 [details] [diff] [review]
Patch v1

If you enter a request also enter a compartment. However is the auto request actually needed?
Comment 2 :Ms2ger 2011-11-25 11:40:13 PST
No idea, this is pre-existing code.
Comment 3 Bobby Holley (busy) 2011-12-01 15:12:15 PST
Comment on attachment 576974 [details] [diff] [review]
Patch v1

I'm hoping this method will go away entirely (see bug693733 comment 13). But in the mean time, this is a righteous change. :-)

Also, I'm not too worried about Andreas' comment, since the code stays the same, and requests are going away anyway in 8 weeks.

>-    argv[0] = OBJECT_TO_JSVAL(obj);
>-    rv = nsXPConnect::GetXPConnect()->GetJSObjectOfWrapper(cx, obj, &obj);
>+    nsresult rv = nsXPConnect::GetXPConnect()->GetJSObjectOfWrapper(aCx, obj, &obj);
>     if (NS_FAILED(rv))
>         return rv;

Looks like we've been assuming nsXPConnect::GetXPConnect() is never null here, which is a likely indicator that the thing in bug 705333 is ok.

Comment 4 Bobby Holley (busy) 2011-12-01 17:50:25 PST
As mentioned in bug 705333, the aFoo argument naming convention needs to be removed here as well.
Comment 5 :Ms2ger 2011-12-03 02:32:12 PST
Looks like you were right after all:
Comment 6 Bobby Holley (busy) 2011-12-03 10:08:19 PST
I'm totally confused - where in the removed code was the compartment being entered?
Comment 7 :Ms2ger 2011-12-03 10:30:26 PST
No idea; I'm removing this code, not claiming to understand what it does :)
Comment 8 Bobby Holley (busy) 2011-12-05 21:11:37 PST
Comment on attachment 576974 [details] [diff] [review]
Patch v1

Ah, right.

>+    nsresult rv = nsXPConnect::GetXPConnect()->GetJSObjectOfWrapper(aCx, obj, &obj);

So this call, among other things, strips security wrappers (including cross-compartment wrappers) off of |obj|...

>-    if (!member->NewFunctionObject(inner_cc, iface,
>-                                   JSVAL_TO_OBJECT(argv[0]),
>-                                   &funval))
>+    if (!member->NewFunctionObject(inner_cc, iface, obj, &funval))

which is precisely why the old code here passes the original argument, rather than obj (which has been clandestinely mutated).

So that needs to be fixed. This was hard to catch because the change in obj happened without any explicit assignment. So let's fix it by introducing a new JSObject called unwrappedObj (or something), and doing GetJSObjectOfWrapper(aCx, obj, &unwrappedObj);
Comment 9 :Ms2ger 2011-12-06 03:16:46 PST
Eek! Thanks for catching that.

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