GNU bug report logs - #36773
27.0.50; Accessing a cached SVG with eww can cause Emacs to crash

Previous Next

Full log

View this message in rfc822 format

From: Pip Cet <pipcet <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: plaiceadam <at> gmail.com, 36773 <at> debbugs.gnu.org
Subject: bug#36773: 27.0.50; Accessing a cached SVG with eww can cause Emacs to crash
Date: Wed, 24 Jul 2019 18:28:20 +0000

On Wed, Jul 24, 2019 at 2:47 PM Eli Zaretskii <eliz <at> gnu.org> wrote:
> > From: Pip Cet <pipcet <at> gmail.com>
> > Date: Wed, 24 Jul 2019 13:24:46 +0000
> > Cc: 36773 <at> debbugs.gnu.org
> >
> > As for the other bug, it's a little tricky: shr calls
> > url-store-in-cache after url-http-parse-headers has decompressed the
> > file, while url-http-parse-headers itself would (correctly) cache the
> > uncompressed file if it were configured to do so. It's not quite clear
> > who's at fault here.
>
> What's more, this problem doesn't happen in Emacs 26.2.90.  Can you
> see why it started happening in Emacs 27?  Maybe that will provide a
> hint as to how to fix it.

-      (zlib-decompress-region (point) (point-max)))))))
+      (zlib-decompress-region (point) (point-max) t))))))

The allow-partial flag means to delete rather than simply leave the
(uncompressed) data in place.

So I guess that is a hint, we could just go back to the Emacs-26
behavior. I don't think we should, but in practice it should work
okay.

> Btw, I see the same behavior as you, Pip: g_object_unref error
> messages and no crash.  librasvg returns a NULL handle, but it also
> returns a non-zero err.  My librsvg version is 2.40.1.

The bug in librsvg was introduced between 2.40.1 and 2.40.13, and has
been fixed again since. 2.40.13 does:

    if (g_buffered_input_stream_fill (G_BUFFERED_INPUT_STREAM
(stream), 2, cancellable, error) != 2) {
        g_object_unref (stream);
        return FALSE;
    }

Which returns without an error filled in if stream doesn't contain at
least two bytes.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.