GraphicsMagick: DetachBlob(): Fix Coverity issue 381869 "Null po...

changeset 6c26fcb005d1 in /hg/GraphicsMagick
details: http://hg.GraphicsMagick.org/hg/GraphicsMagick?cmd=changeset;node=6c26fcb005d1
summary: DetachBlob(): Fix Coverity issue 381869 "Null pointer dereferences (FORWARD_NULL)"

diffstat:

 ChangeLog          |  4 ++++
 magick/blob.c      |  3 ++-
 www/Changelog.html |  3 +++
 3 files changed, 9 insertions(+), 1 deletions(-)

diffs (39 lines):

diff -r d3f42947a065 -r 6c26fcb005d1 ChangeLog
--- a/ChangeLog	Tue Nov 08 14:26:49 2022 -0600
+++ b/ChangeLog	Tue Nov 08 14:38:48 2022 -0600
@@ -1,5 +1,9 @@
 2022-11-08  Bob Friesenhahn  <[email protected]>
 
+	* magick/blob.c (DetachBlob): Do not dereference blob_info->data
+	if it is null.  Addresses Coverity issue 381869 "Null pointer
+	dereferences (FORWARD_NULL)".
+
 	* coders/jpeg.c (FreeMagickClientData): Fix Coverity issue 381870
 	"Null pointer dereferences".
 
diff -r d3f42947a065 -r 6c26fcb005d1 magick/blob.c
--- a/magick/blob.c	Tue Nov 08 14:26:49 2022 -0600
+++ b/magick/blob.c	Tue Nov 08 14:38:48 2022 -0600
@@ -1283,7 +1283,8 @@
  assert(blob_info != (BlobInfo *) NULL);
   if (blob_info->mapped)
     {
-      (void) UnmapBlob(blob_info->data,blob_info->length);
+      if (blob_info->data != (unsigned char *) NULL)
+        (void) UnmapBlob(blob_info->data,blob_info->length);
       LiberateMagickResource(MapResource,blob_info->length);
     }
   blob_info->mapped=MagickFalse;
diff -r d3f42947a065 -r 6c26fcb005d1 www/Changelog.html
--- a/www/Changelog.html	Tue Nov 08 14:26:49 2022 -0600
+++ b/www/Changelog.html	Tue Nov 08 14:38:48 2022 -0600
@@ -40,6 +40,9 @@
 <p>2022-11-08  Bob Friesenhahn  &lt;<a class="reference external" href="mailto:bfriesen&#37;&#52;&#48;simple&#46;dallas&#46;tx&#46;us">bfriesen<span>&#64;</span>simple<span>&#46;</span>dallas<span>&#46;</span>tx<span>&#46;</span>us</a>&gt;</p>
 <blockquote>
 <ul class="simple">
+<li><p>magick/blob.c (DetachBlob): Do not dereference blob_info-&gt;data
+if it is null.  Addresses Coverity issue 381869 &quot;Null pointer
+dereferences (FORWARD_NULL)&quot;.</p></li>
 <li><p>coders/jpeg.c (FreeMagickClientData): Fix Coverity issue 381870
 &quot;Null pointer dereferences&quot;.</p></li>
 <li><p>magick/export.c (ExportViewPixelArea): Fix Coverity issue 381871