#621 Assertion in WriteBlob at magick/blob.c:4937

[Suhwan Song]

Hi, I found an Assertion in WriteBlob at magick/blob.c:4937
I tested it in GraphicsMagick 1.4
how to reproduce :

gm convert $PoC tmp.jng

gm: magick/blob.c:4937: size_t WriteBlob(Image *, const size_t, const void *): assertion `data != (const char *) NULL'.
./gm convert: abort due to signal 6 (SIGABRT) "Abort"...

GraphicsMagick 1.4 snapshot-20200104 Q8 http://www.GraphicsMagick.org/
Copyright (C) 2002-2020 GraphicsMagick Group.
Additional copyrights and licenses apply to this software.
See http://www.GraphicsMagick.org/www/Copyright.html for details.

Feature Support:
Native Thread Safe yes
Large Files (> 32 bit) yes
Large Memory (> 32 bit) yes
BZIP yes
DPS no
FlashPix no
FreeType yes
Ghostscript (Library) no
JBIG yes
JPEG-2000 no
JPEG yes
Little CMS yes
Loadable Modules no
Solaris mtmalloc no
OpenMP yes (201107 "3.1")
PNG yes
TIFF yes
TRIO no
Solaris umem no
WebP no
WMF no
X11 yes
XML yes
ZLIB yes

Host type: x86_64-pc-linux-gnu

[Bob Friesenhahn]

This problem is fixed by Mercurial changeset 16203:085f95f92eae. Thanks for the report!