forcemerge 671002 670980 severity 671002 grave tag 671002 security thanks Hello,
On Tue, May 1, 2012 at 6:44 PM, Matthew Somerville <matt...@mysociety.org> wrote: > We are having this issue too, and it has caused our live site to go down once > (due to segfaulting on perfectly respectable JPEGs, quite ironic given this > patch was meant to prevent DoS due to malicious JPEGs :-) ). > > After some investigation, the issue appears to be in the code applied by > patch 0002-Fix-security-holes-JPEG-EXIF-TIFF.patch - the following two lines > in coders/jpeg.c: > > + if (jpeg_info->err->num_warnings++ > 1000) /* 1000 = JPEGEcessiveWarnings > */ > + JPEGErrorHandler(jpeg_info); > > are not placed where the patch on > http://www.imagemagick.org/discourse-server/viewtopic.php?f=4&t=20629 implies > they should be (ie. directly above the if statement within the level<0 if > statement). Moving these two lines down the few lines to that location and > recompiling stops the segfaulting on the JPEGs previously causing the issue. > > I don't know enough about the ImageMagick source code to know if that is > entirely the solution, but I hope is helpful in diagnosing this problem. Thanks a lot for the investigation. I regret having uploaded the fix with not enough testing. Would it be possible for you to provide me with examples of JPEGs giving segfaults (by private mail if you can't have them publicly available on the bug tracker), in order to make sure that the (new) fix is correct ? Cheers, Vincent -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
