[Bug 1793485] [NEW] segfault in png to gif conversion

[Dariusz Gadomski]

Public bug reported:

Regression between 8:6.8.9.9-7ubuntu5.9 and 8:6.8.9.9-7ubuntu5.12.

Test case:
1. Download the attached pngs.
2. Run:
/usr/bin/convert -limit memory 512MiB -limit map 0MiB -limit file 10 -delay 16 -loop 0 -coalesce -deconstruct ./*.png ./output.gif

Expected result:
Process finishes with resulting output.gif.

Actual result:
Process is aborted with SIGSEGV:

Other information:
In my tests looks like it has been introduced in 8:6.8.9.9-7ubuntu5.11 and does not occur on Bionic.

Stack trace:
#0  EncodeImage (image_info=0x645c40, data_size=<optimized out>, 
    image=0x636890) at ../../coders/gif.c:676
#1  WriteGIFImage (image_info=0x640700, image=0x636890)
    at ../../coders/gif.c:1905
#2  0x00007ffff79a5f0f in WriteImage (image_info=image_info at entry=0x618680, 
    image=image at entry=0x62cb30) at ../../magick/constitute.c:1184
#3  0x00007ffff79a684f in WriteImages (image_info=image_info at entry=0x60fcd0, 
    images=<optimized out>, images at entry=0x62cb30, filename=<optimized out>, 
    exception=exception at entry=0x602ea0) at ../../magick/constitute.c:1335
#4  0x00007ffff763e84e in ConvertImageCommand (image_info=0x60fcd0, argc=19, 
    argv=0x6143b0, metadata=0x0, exception=0x602ea0)
    at ../../wand/convert.c:3215
#5  0x00007ffff76ab527 in MagickCommandGenesis (
    image_info=image_info at entry=0x60aab0, 
    command=0x4007f0 <ConvertImageCommand at plt>, argc=argc at entry=19, 
    argv=argv at entry=0x7fffffffdc68, metadata=metadata at entry=0x0, 
    exception=exception at entry=0x602ea0) at ../../wand/mogrify.c:168
#6  0x0000000000400877 in ConvertMain (argv=0x7fffffffdc68, argc=19)
    at ../../utilities/convert.c:81
#7  main (argc=19, argv=0x7fffffffdc68) at ../../utilities/convert.c:92

** Affects: imagemagick (Ubuntu)
     Importance: High
         Status: New


** Tags: regression regression-update

** Attachment added: "SH_HL_08_Step1_F028.png"
   https://bugs.launchpad.net/bugs/1793485/+attachment/5190921/+files/SH_HL_08_Step1_F028.png

** Changed in: imagemagick (Ubuntu)
   Importance: Undecided => High

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to imagemagick in Ubuntu.
https://bugs.launchpad.net/bugs/1793485

Title:
  segfault in png to gif conversion

Status in imagemagick package in Ubuntu:
  New

Bug description:
  Regression between 8:6.8.9.9-7ubuntu5.9 and 8:6.8.9.9-7ubuntu5.12.

  Test case:
  1. Download the attached pngs.
  2. Run:
  /usr/bin/convert -limit memory 512MiB -limit map 0MiB -limit file 10 -delay 16 -loop 0 -coalesce -deconstruct ./*.png ./output.gif

  Expected result:
  Process finishes with resulting output.gif.

  Actual result:
  Process is aborted with SIGSEGV:

  Other information:
  In my tests looks like it has been introduced in 8:6.8.9.9-7ubuntu5.11 and does not occur on Bionic.

  Stack trace:
  #0  EncodeImage (image_info=0x645c40, data_size=<optimized out>, 
      image=0x636890) at ../../coders/gif.c:676
  #1  WriteGIFImage (image_info=0x640700, image=0x636890)
      at ../../coders/gif.c:1905
  #2  0x00007ffff79a5f0f in WriteImage (image_info=image_info at entry=0x618680, 
      image=image at entry=0x62cb30) at ../../magick/constitute.c:1184
  #3  0x00007ffff79a684f in WriteImages (image_info=image_info at entry=0x60fcd0, 
      images=<optimized out>, images at entry=0x62cb30, filename=<optimized out>, 
      exception=exception at entry=0x602ea0) at ../../magick/constitute.c:1335
  #4  0x00007ffff763e84e in ConvertImageCommand (image_info=0x60fcd0, argc=19, 
      argv=0x6143b0, metadata=0x0, exception=0x602ea0)
      at ../../wand/convert.c:3215
  #5  0x00007ffff76ab527 in MagickCommandGenesis (
      image_info=image_info at entry=0x60aab0, 
      command=0x4007f0 <ConvertImageCommand at plt>, argc=argc at entry=19, 
      argv=argv at entry=0x7fffffffdc68, metadata=metadata at entry=0x0, 
      exception=exception at entry=0x602ea0) at ../../wand/mogrify.c:168
  #6  0x0000000000400877 in ConvertMain (argv=0x7fffffffdc68, argc=19)
      at ../../utilities/convert.c:81
  #7  main (argc=19, argv=0x7fffffffdc68) at ../../utilities/convert.c:92

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/imagemagick/+bug/1793485/+subscriptions