Commit message: https://github.com/ImageMagick/ImageMagick/issues/1520
CVE: CVE-2019-12976
CWE: CWE-401
Vulnerability description: ImageMagick 7.0.8-34 has a memory leak in the ReadPCLImage function in coders/pcl.c.

Project: ImageMagick6
File: pcl.c

static Image *ReadPCLImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
#define CropBox  "CropBox"
#define DeviceCMYK  "DeviceCMYK"
#define MediaBox  "MediaBox"
#define RenderPCLText  "  Rendering PCL...  "

  char
    command[MaxTextExtent],
    *density,
    filename[MaxTextExtent],
    geometry[MaxTextExtent],
    *options,
    input_filename[MaxTextExtent];

  const DelegateInfo
    *delegate_info;

  Image
    *image,
    *next_image;

  ImageInfo
    *read_info;

  int
    c;

  MagickBooleanType
    cmyk,
    status;

  PointInfo
    delta;

  RectangleInfo
    bounding_box,
    page;

  register char
    *p;

  SegmentInfo
    bounds;

  size_t
    height,
    width;

  ssize_t
    count;

  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickCoreSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickCoreSignature);
  /*
    Open image file.
  */
  image=AcquireImage(image_info);
  status=OpenBlob(image_info,image,ReadBinaryBlobMode,exception);
  if (status == MagickFalse)
    {
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  status=AcquireUniqueSymbolicLink(image_info->filename,input_filename);
  if (status == MagickFalse)
    {
      ThrowFileException(exception,FileOpenError,"UnableToCreateTemporaryFile",
        image_info->filename);
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  /*
    Set the page density.
  */
  delta.x=DefaultResolution;
  delta.y=DefaultResolution;
  if ((image->x_resolution == 0.0) || (image->y_resolution == 0.0))
    {
      GeometryInfo
        geometry_info;

      MagickStatusType
        flags;

      flags=ParseGeometry(PSDensityGeometry,&geometry_info);
      image->x_resolution=geometry_info.rho;
      image->y_resolution=geometry_info.sigma;
      if ((flags & SigmaValue) == 0)
        image->y_resolution=image->x_resolution;
    }
  /*
    Determine page geometry from the PCL media box.
  */
  cmyk=image->colorspace == CMYKColorspace ? MagickTrue : MagickFalse;
  count=0;
  (void) memset(&bounding_box,0,sizeof(bounding_box));
  (void) memset(&bounds,0,sizeof(bounds));
  (void) memset(&page,0,sizeof(page));
  (void) memset(command,0,sizeof(command));
  p=command;
  for (c=ReadBlobByte(image); c != EOF; c=ReadBlobByte(image))
  {
    if (image_info->page != (char *) NULL)
      continue;
    /*
      Note PCL elements.
    */
    *p++=(char) c;
    if ((c != (int) '/') && (c != '\n') &&
        ((size_t) (p-command) < (MaxTextExtent-1)))
      continue;
    *p='\0';
    p=command;
    /*
      Is this a CMYK document?
    */
    if (LocaleNCompare(DeviceCMYK,command,strlen(DeviceCMYK)) == 0)
      cmyk=MagickTrue;
    if (LocaleNCompare(CropBox,command,strlen(CropBox)) == 0)
      {
        /*
          Note region defined by crop box.
        */
        count=(ssize_t) sscanf(command,"CropBox [%lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        if (count != 4)
          count=(ssize_t) sscanf(command,"CropBox[%lf %lf %lf %lf",
            &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
      }
    if (LocaleNCompare(MediaBox,command,strlen(MediaBox)) == 0)
      {
        /*
          Note region defined by media box.
        */
        count=(ssize_t) sscanf(command,"MediaBox [%lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        if (count != 4)
          count=(ssize_t) sscanf(command,"MediaBox[%lf %lf %lf %lf",
            &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
      }
    if (count != 4)
      continue;
    /*
      Set PCL render geometry.
    */
    width=(size_t) floor(bounds.x2-bounds.x1+0.5);
    height=(size_t) floor(bounds.y2-bounds.y1+0.5);
    if (width > page.width)
      page.width=width;
    if (height > page.height)
      page.height=height;
  }
  (void) CloseBlob(image);
  /*
    Render PCL with the GhostPCL delegate.
  */
  if ((page.width == 0) || (page.height == 0))
    (void) ParseAbsoluteGeometry(PSPageGeometry,&page);
  if (image_info->page != (char *) NULL)
    (void) ParseAbsoluteGeometry(image_info->page,&page);
  (void) FormatLocaleString(geometry,MaxTextExtent,"%.20gx%.20g",(double)
    page.width,(double) page.height);
  if (image_info->monochrome != MagickFalse)
    delegate_info=GetDelegateInfo("pcl:mono",(char *) NULL,exception);
  else
     if (cmyk != MagickFalse)
       delegate_info=GetDelegateInfo("pcl:cmyk",(char *) NULL,exception);
     else
       delegate_info=GetDelegateInfo("pcl:color",(char *) NULL,exception);
  if (delegate_info == (const DelegateInfo *) NULL)
    return((Image *) NULL);
  if ((page.width == 0) || (page.height == 0))
    (void) ParseAbsoluteGeometry(PSPageGeometry,&page);
  if (image_info->page != (char *) NULL)
    (void) ParseAbsoluteGeometry(image_info->page,&page);
  density=AcquireString("");
  options=AcquireString("");
  (void) FormatLocaleString(density,MaxTextExtent,"%gx%g",
    image->x_resolution,image->y_resolution);
  page.width=(size_t) floor((double) page.width*image->x_resolution/delta.x+
    0.5);
  page.height=(size_t) floor((double) page.height*image->y_resolution/delta.y+
    0.5);
  (void) FormatLocaleString(options,MaxTextExtent,"-g%.20gx%.20g ",(double)
     page.width,(double) page.height);
  image=DestroyImage(image);
  read_info=CloneImageInfo(image_info);
  *read_info->magick='\0';
  if (read_info->number_scenes != 0)
    {
      if (read_info->number_scenes != 1)
        (void) FormatLocaleString(options,MaxTextExtent,"-dLastPage=%.20g",
          (double) (read_info->scene+read_info->number_scenes));
      else
        (void) FormatLocaleString(options,MaxTextExtent,
          "-dFirstPage=%.20g -dLastPage=%.20g",(double) read_info->scene+1,
          (double) (read_info->scene+read_info->number_scenes));
      read_info->number_scenes=0;
      if (read_info->scenes != (char *) NULL)
        *read_info->scenes='\0';
    }
  (void) CopyMagickString(filename,read_info->filename,MaxTextExtent);
  (void) AcquireUniqueFilename(read_info->filename);
  (void) FormatLocaleString(command,MaxTextExtent,
    GetDelegateCommands(delegate_info),
    read_info->antialias != MagickFalse ? 4 : 1,
    read_info->antialias != MagickFalse ? 4 : 1,density,options,
    read_info->filename,input_filename);
  options=DestroyString(options);
  density=DestroyString(density);
  status=ExternalDelegateCommand(MagickFalse,read_info->verbose,command,
    (char *) NULL,exception) != 0 ? MagickTrue : MagickFalse;
  image=ReadImage(read_info,exception);
  (void) RelinquishUniqueFileResource(read_info->filename);
  (void) RelinquishUniqueFileResource(input_filename);
  read_info=DestroyImageInfo(read_info);
  if (image == (Image *) NULL)
    ThrowReaderException(DelegateError,"PCLDelegateFailed");
  if (LocaleCompare(image->magick,"BMP") == 0)
    {
      Image
        *cmyk_image;

      cmyk_image=ConsolidateCMYKImages(image,&image->exception);
      if (cmyk_image != (Image *) NULL)
        {
          image=DestroyImageList(image);
          image=cmyk_image;
        }
    }
  do
  {
    (void) CopyMagickString(image->filename,filename,MaxTextExtent);
    image->page=page;
    next_image=SyncNextImageInList(image);
    if (next_image != (Image *) NULL)
      image=next_image;
  } while (next_image != (Image *) NULL);
  return(GetFirstImageInList(image));
}