158697 - Corrupt image should give partial display.

Status: VERIFIED DUPLICATE of bug 150611

(Core :: Graphics: ImageLib, defect)

Description

[Jason Bassford]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.1b) Gecko/20020722
BuildID:    2002072204

The URL as reported above, an attachment from bug 150317, is a corrupt PNG
image.  When Mozilla loads the image it briefly displays (part of) it, then
immediately replaces what it's drawn with the following text:

The image “http://bugzilla.mozilla.org/attachment.cgi?id=86980&action=view”
cannot be displayed, because it contains errors.

However, Mozilla WAS able to display at least part of it before it stopped and
generated the error message.  (You can use IE to go to the URL and see what
Mozilla drew before it stopped and complained.)

Unless there are security issues, I think that Mozilla should display as much of
the corrupt image as its capable of displaying.  If there *are* security issues,
and they are fixable, then they should be addressed in this bug, unless there
are already open bugs on them - in which case they should be marked as blocking
this bug.

If there are other legitimate reasons for not displaying just a partial graphic
image (this shouldn't be about Mozilla displaying what it can just because
that's what IE does) then I'd be happy to close this bug.

Reproducible: Always
Steps to Reproduce:
1. Visit the reference URL.

Actual Results:  Image is partially drawn, then Mozilla stops and displays
stated error message instead.

Expected Results:  Mozilla should only display the error message if NONE of the
image can be drawn.  If there is some usable data, I think that a partially
displayed image is preferable.

Comment 1

[Jason Bassford]

libpng error: Too much data in IDAT chunks

Comment 2

[Matthias Versen [:Matti]]

this image works in Mozilla1.0 and I think i saw a recent PNG securtiy checking
which could explain this ...

Comment 3

[Christian :Biesinger (don't email me, ping me on IRC)]

*** This bug has been marked as a duplicate of 150611 ***

Comment 4

[Jason Bassford]

.

Comment 5

[Jason Bassford]

.