Re: [PATCH] xcb: Fix error reporting if fallback fails
Uli Schlachter <[email protected]>
| Newsgroups | gmane.comp.lib.cairo |
|---|---|
| Message-ID | <[email protected]> |
On 07.06.2017 02:51, Bryce Harrington wrote: [...] >> [No test for this since in the case were I ran into this, _get_image() >> failed because the X11 server closed the connection. No idea why it >> did that.] > > Steps to repro the issue (or a bug # if it's been reported) might be > nice, but the change looks sensible enough so: By now I figured out: At my university, there was an ancient version of x11vnc which mis-applied the maximum request length for X11 requests. Also, instead of the required BadLength error, it just closed the client's connection. (I tried to find the fixes for this in some Git repositories, but I failed. But I did check that this does not happen with newer versions of x11vnc.) Thus, when the window manager called awesome tried to set a wallpaper, the server closed the X11 connection. This caused some following wallpaper-related things to fail and then cairo dereferenced a NULL pointer. Since the above was never reported through cairo's bugzilla, there is no bug number for it. Also, due to "old x11vnc version" I do not have any "good" reproduction steps. The best I could offer: Hack the source code so that the fallback fails and returns a surface in an error state. > Reviewed-by: Bryce Harrington <[email protected]> Sorry, I didn't see this before pushing the patch. Cheers, Uli -- 99 little bugs in the code 99 little bugs in the code Take one down, patch it around 117 little bugs in the code -- @irqed -- cairo mailing list [email protected] https://lists.cairographics.org/mailman/listinfo/cairo