211085 - XUL applications bypass image blocking when loading remote images

Status: NEW

(Core :: Graphics: Image Blocking, defect)

Description

[Tim]

Currently, XUL's nsImageBoxFrame fail to check with content policy before
loading remote images.  I'm still investigating where a content policy check
could be injected; ::UpdateImage is looking like a reasonable candidate.

Note that placing a check here will necessitate the removal of the content
policy check from nsImageLoadingContent.cpp, since everybody goes through
nsImageBoxFrame, and there's no good reason for duplicate content policy checks.

Comment 1

[Frederic Bezies]

It looks like a bug I saw in thunderbird. Even having unckecked "load remote
image" in TB preferences, some mails are loading them.

Comment 2

[Boris Zbarsky [:bzbarsky]]

> Note that placing a check here will necessitate the removal of the content
> policy check from nsImageLoadingContent.cpp, since everybody goes through
> nsImageBoxFrame

I can't name a single case when a caller would go through both
nsImageLoadingContent and nsImageBoxFrame.  Can you?

Comment 3

[Tim]

re: comment 2: nope; I had misunderstood some output; ignore that part of the
comment.