Commit message: None
CVE: CVE-2017-14172
CWE: CWE-834
Vulnerability description: In coders/ps.c in ImageMagick 7.0.7-0 Q16, a DoS in ReadPSImage() due to lack of an EOF (End of File) check might cause huge CPU consumption. When a crafted PSD file, which claims a large "extent" field in the header but does not contain sufficient backing data, is provided, the loop over "length" would consume huge CPU resources, since there is no EOF check inside the loop.

Project: ImageMagick

static Image *ReadPSImage(const ImageInfo *image_info,ExceptionInfo *exception)
{
#define BoundingBox  "BoundingBox:"
#define BeginDocument  "BeginDocument:"
#define BeginXMPPacket  "<?xpacket begin="
#define EndXMPPacket  "<?xpacket end="
#define ICCProfile "BeginICCProfile:"
#define CMYKCustomColor  "CMYKCustomColor:"
#define CMYKProcessColor  "CMYKProcessColor:"
#define DocumentMedia  "DocumentMedia:"
#define DocumentCustomColors  "DocumentCustomColors:"
#define DocumentProcessColors  "DocumentProcessColors:"
#define EndDocument  "EndDocument:"
#define HiResBoundingBox  "HiResBoundingBox:"
#define ImageData  "ImageData:"
#define PageBoundingBox  "PageBoundingBox:"
#define LanguageLevel  "LanguageLevel:"
#define PageMedia  "PageMedia:"
#define Pages  "Pages:"
#define PhotoshopProfile  "BeginPhotoshop:"
#define PostscriptLevel  "!PS-"
#define RenderPostscriptText  "  Rendering Postscript...  "
#define SpotColor  "+ "

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

  const char
    *option;

  const DelegateInfo
    *delegate_info;

  GeometryInfo
    geometry_info;

  Image
    *image,
    *next,
    *postscript_image;

  ImageInfo
    *read_info;

  int
    c,
    file;

  MagickBooleanType
    cmyk,
    fitPage,
    skip,
    status;

  MagickStatusType
    flags;

  PointInfo
    delta,
    resolution;

  RectangleInfo
    page;

  register char
    *p;

  register ssize_t
    i;

  SegmentInfo
    bounds,
    hires_bounds;

  short int
    hex_digits[256];

  size_t
    length,
    priority;

  ssize_t
    count;

  StringInfo
    *profile;

  unsigned long
    columns,
    extent,
    language_level,
    pages,
    rows,
    scene,
    spotcolor;

  /*
    Open image file.
  */
  assert(image_info != (const ImageInfo *) NULL);
  assert(image_info->signature == MagickSignature);
  if (image_info->debug != MagickFalse)
    (void) LogMagickEvent(TraceEvent,GetMagickModule(),"%s",
      image_info->filename);
  assert(exception != (ExceptionInfo *) NULL);
  assert(exception->signature == MagickSignature);
  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);
    }
  /*
    Initialize hex values.
  */
  (void) ResetMagickMemory(hex_digits,0,sizeof(hex_digits));
  hex_digits[(int) '0']=0;
  hex_digits[(int) '1']=1;
  hex_digits[(int) '2']=2;
  hex_digits[(int) '3']=3;
  hex_digits[(int) '4']=4;
  hex_digits[(int) '5']=5;
  hex_digits[(int) '6']=6;
  hex_digits[(int) '7']=7;
  hex_digits[(int) '8']=8;
  hex_digits[(int) '9']=9;
  hex_digits[(int) 'a']=10;
  hex_digits[(int) 'b']=11;
  hex_digits[(int) 'c']=12;
  hex_digits[(int) 'd']=13;
  hex_digits[(int) 'e']=14;
  hex_digits[(int) 'f']=15;
  hex_digits[(int) 'A']=10;
  hex_digits[(int) 'B']=11;
  hex_digits[(int) 'C']=12;
  hex_digits[(int) 'D']=13;
  hex_digits[(int) 'E']=14;
  hex_digits[(int) 'F']=15;
  /*
    Set the page density.
  */
  delta.x=DefaultResolution;
  delta.y=DefaultResolution;
  if ((image->x_resolution == 0.0) || (image->y_resolution == 0.0))
    {
      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;
    }
  if (image_info->density != (char *) NULL)
    {
      flags=ParseGeometry(image_info->density,&geometry_info);
      image->x_resolution=geometry_info.rho;
      image->y_resolution=geometry_info.sigma;
      if ((flags & SigmaValue) == 0)
        image->y_resolution=image->x_resolution;
    }
  (void) ParseAbsoluteGeometry(PSPageGeometry,&page);
  if (image_info->page != (char *) NULL)
    (void) ParseAbsoluteGeometry(image_info->page,&page);
  resolution.x=image->x_resolution;
  resolution.y=image->y_resolution;
  page.width=(size_t) ceil((double) (page.width*resolution.x/delta.x)-0.5);
  page.height=(size_t) ceil((double) (page.height*resolution.y/delta.y)-0.5);
  /*
    Determine page geometry from the Postscript bounding box.
  */
  (void) ResetMagickMemory(&bounds,0,sizeof(bounds));
  (void) ResetMagickMemory(command,0,sizeof(command));
  cmyk=image_info->colorspace == CMYKColorspace ? MagickTrue : MagickFalse;
  (void) ResetMagickMemory(&hires_bounds,0,sizeof(hires_bounds));
  priority=0;
  columns=0;
  rows=0;
  extent=0;
  spotcolor=0;
  language_level=1;
  skip=MagickFalse;
  pages=(~0UL);
  p=command;
  for (c=ReadBlobByte(image); c != EOF; c=ReadBlobByte(image))
  {
    /*
      Note document structuring comments.
    */
    *p++=(char) c;
    if ((strchr("\n\r%",c) == (char *) NULL) &&
        ((size_t) (p-command) < (MaxTextExtent-1)))
      continue;
    *p='\0';
    p=command;
    /*
      Skip %%BeginDocument thru %%EndDocument.
    */
    if (LocaleNCompare(BeginDocument,command,strlen(BeginDocument)) == 0)
      skip=MagickTrue;
    if (LocaleNCompare(EndDocument,command,strlen(EndDocument)) == 0)
      skip=MagickFalse;
    if (skip != MagickFalse)
      continue;
    if (LocaleNCompare(PostscriptLevel,command,strlen(PostscriptLevel)) == 0)
      {
        (void) SetImageProperty(image,"ps:Level",command+4);
        if (GlobExpression(command,"*EPSF-*",MagickTrue) != MagickFalse)
          pages=1;
      }
    if (LocaleNCompare(LanguageLevel,command,strlen(LanguageLevel)) == 0)
      (void) sscanf(command,LanguageLevel " %lu",&language_level);
    if (LocaleNCompare(Pages,command,strlen(Pages)) == 0)
      (void) sscanf(command,Pages " %lu",&pages);
    if (LocaleNCompare(ImageData,command,strlen(ImageData)) == 0)
      (void) sscanf(command,ImageData " %lu %lu",&columns,&rows);
    if (LocaleNCompare(ICCProfile,command,strlen(ICCProfile)) == 0)
      {
        unsigned char
          *datum;

        /*
          Read ICC profile.
        */
        profile=AcquireStringInfo(MaxTextExtent);
        datum=GetStringInfoDatum(profile);
        for (i=0; (c=ProfileInteger(image,hex_digits)) != EOF; i++)
        {
          if (i >= (ssize_t) GetStringInfoLength(profile))
            {
              SetStringInfoLength(profile,(size_t) i << 1);
              datum=GetStringInfoDatum(profile);
            }
          datum[i]=(unsigned char) c;
        }
        SetStringInfoLength(profile,(size_t) i+1);
        (void) SetImageProfile(image,"icc",profile);
        profile=DestroyStringInfo(profile);
        continue;
      }
    if (LocaleNCompare(PhotoshopProfile,command,strlen(PhotoshopProfile)) == 0)
      {
        unsigned char
          *p;

        /*
          Read Photoshop profile.
        */
        count=(ssize_t) sscanf(command,PhotoshopProfile " %lu",&extent);
         if (count != 1)
           continue;
         length=extent;
         profile=BlobToStringInfo((const void *) NULL,length);
         if (profile != (StringInfo *) NULL)
           {
            p=GetStringInfoDatum(profile);
            for (i=0; i < (ssize_t) length; i++)
              *p++=(unsigned char) ProfileInteger(image,hex_digits);
            (void) SetImageProfile(image,"8bim",profile);
            profile=DestroyStringInfo(profile);
          }
        continue;
      }
    if (LocaleNCompare(BeginXMPPacket,command,strlen(BeginXMPPacket)) == 0)
      {
        register size_t
          i;

        /*
          Read XMP profile.
        */
        p=command;
        profile=StringToStringInfo(command);
        for (i=GetStringInfoLength(profile)-1; c != EOF; i++)
        {
          SetStringInfoLength(profile,i+1);
          c=ReadBlobByte(image);
          GetStringInfoDatum(profile)[i]=(unsigned char) c;
          *p++=(char) c;
          if ((strchr("\n\r%",c) == (char *) NULL) &&
              ((size_t) (p-command) < (MaxTextExtent-1)))
            continue;
          *p='\0';
          p=command;
          if (LocaleNCompare(EndXMPPacket,command,strlen(EndXMPPacket)) == 0)
            break;
        }
        SetStringInfoLength(profile,i);
        (void) SetImageProfile(image,"xmp",profile);
        profile=DestroyStringInfo(profile);
        continue;
      }
    /*
      Is this a CMYK document?
    */
    length=strlen(DocumentProcessColors);
    if (LocaleNCompare(DocumentProcessColors,command,length) == 0)
      {
        if ((GlobExpression(command,"*Cyan*",MagickTrue) != MagickFalse) ||
            (GlobExpression(command,"*Magenta*",MagickTrue) != MagickFalse) ||
            (GlobExpression(command,"*Yellow*",MagickTrue) != MagickFalse))
          cmyk=MagickTrue;
      }
    if (LocaleNCompare(CMYKCustomColor,command,strlen(CMYKCustomColor)) == 0)
      cmyk=MagickTrue;
    if (LocaleNCompare(CMYKProcessColor,command,strlen(CMYKProcessColor)) == 0)
      cmyk=MagickTrue;
    length=strlen(DocumentCustomColors);
    if ((LocaleNCompare(DocumentCustomColors,command,length) == 0) ||
        (LocaleNCompare(CMYKCustomColor,command,strlen(CMYKCustomColor)) == 0) ||
        (LocaleNCompare(SpotColor,command,strlen(SpotColor)) == 0))
      {
        char
          property[MaxTextExtent],
          *value;

        register char
          *p;

        /*
          Note spot names.
        */
        (void) FormatLocaleString(property,MaxTextExtent,"ps:SpotColor-%.20g",
          (double) (spotcolor++));
        for (p=command; *p != '\0'; p++)
          if (isspace((int) (unsigned char) *p) != 0)
            break;
        value=AcquireString(p);
        (void) SubstituteString(&value,"(","");
        (void) SubstituteString(&value,")","");
        (void) StripString(value);
        (void) SetImageProperty(image,property,value);
        value=DestroyString(value);
        continue;
      }
    if (image_info->page != (char *) NULL)
      continue;
    /*
      Note region defined by bounding box.
    */
    count=0;
    i=0;
    if (LocaleNCompare(BoundingBox,command,strlen(BoundingBox)) == 0)
      {
        count=(ssize_t) sscanf(command,BoundingBox " %lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        i=2;
      }
    if (LocaleNCompare(DocumentMedia,command,strlen(DocumentMedia)) == 0)
      {
        count=(ssize_t) sscanf(command,DocumentMedia " %lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        i=1;
      }
    if (LocaleNCompare(HiResBoundingBox,command,strlen(HiResBoundingBox)) == 0)
      {
        count=(ssize_t) sscanf(command,HiResBoundingBox " %lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        i=3;
      }
    if (LocaleNCompare(PageBoundingBox,command,strlen(PageBoundingBox)) == 0)
      {
        count=(ssize_t) sscanf(command,PageBoundingBox " %lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        i=1;
      }
    if (LocaleNCompare(PageMedia,command,strlen(PageMedia)) == 0)
      {
        count=(ssize_t) sscanf(command,PageMedia " %lf %lf %lf %lf",
          &bounds.x1,&bounds.y1,&bounds.x2,&bounds.y2);
        i=1;
      }
    if ((count != 4) || (i < (ssize_t) priority))
      continue;
    if ((fabs(bounds.x2-bounds.x1) <= fabs(hires_bounds.x2-hires_bounds.x1)) ||
        (fabs(bounds.y2-bounds.y1) <= fabs(hires_bounds.y2-hires_bounds.y1)))
      if (i == (ssize_t) priority)
        continue;
    hires_bounds=bounds;
    priority=i;
  }
  if ((fabs(hires_bounds.x2-hires_bounds.x1) >= MagickEpsilon) &&
      (fabs(hires_bounds.y2-hires_bounds.y1) >= MagickEpsilon))
    {
      /*
        Set Postscript render geometry.
      */
      (void) FormatLocaleString(geometry,MaxTextExtent,"%gx%g%+.15g%+.15g",
        hires_bounds.x2-hires_bounds.x1,hires_bounds.y2-hires_bounds.y1,
        hires_bounds.x1,hires_bounds.y1);
      (void) SetImageProperty(image,"ps:HiResBoundingBox",geometry);
      page.width=(size_t) ceil((double) ((hires_bounds.x2-hires_bounds.x1)*
        resolution.x/delta.x)-0.5);
      page.height=(size_t) ceil((double) ((hires_bounds.y2-hires_bounds.y1)*
        resolution.y/delta.y)-0.5);
    }
  fitPage=MagickFalse;
  option=GetImageOption(image_info,"eps:fit-page");
  if (option != (char *) NULL)
  {
    char
      *geometry;

    MagickStatusType
      flags;

    geometry=GetPageGeometry(option);
    flags=ParseMetaGeometry(geometry,&page.x,&page.y,&page.width,&page.height);
    if (flags == NoValue)
      {
        (void) ThrowMagickException(exception,GetMagickModule(),OptionError,
          "InvalidGeometry","`%s'",option);
        image=DestroyImage(image);
        return((Image *) NULL);
      }
    page.width=(size_t) ceil((double) (page.width*image->x_resolution/delta.x)
      -0.5);
    page.height=(size_t) ceil((double) (page.height*image->y_resolution/
      delta.y) -0.5);
    geometry=DestroyString(geometry);
    fitPage=MagickTrue;
  }
  (void) CloseBlob(image);
  if (IssRGBCompatibleColorspace(image_info->colorspace) != MagickFalse)
    cmyk=MagickFalse;
  /*
    Create Ghostscript control file.
  */
  file=AcquireUniqueFileResource(postscript_filename);
  if (file == -1)
    {
      ThrowFileException(&image->exception,FileOpenError,"UnableToOpenFile",
        image_info->filename);
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  (void) CopyMagickString(command,"/setpagedevice {pop} bind 1 index where {"
    "dup wcheck {3 1 roll put} {pop def} ifelse} {def} ifelse\n"
    "<</UseCIEColor true>>setpagedevice\n",MaxTextExtent);
  count=write(file,command,(unsigned int) strlen(command));
  if (image_info->page == (char *) NULL)
    {
      char
        translate_geometry[MaxTextExtent];

      (void) FormatLocaleString(translate_geometry,MaxTextExtent,
        "%g %g translate\n",-hires_bounds.x1,-hires_bounds.y1);
      count=write(file,translate_geometry,(unsigned int)
        strlen(translate_geometry));
    }
  file=close(file)-1;
  /*
    Render Postscript with the Ghostscript delegate.
  */
  if (image_info->monochrome != MagickFalse)
    delegate_info=GetDelegateInfo("ps:mono",(char *) NULL,exception);
  else
    if (cmyk != MagickFalse)
      delegate_info=GetDelegateInfo("ps:cmyk",(char *) NULL,exception);
    else
      delegate_info=GetDelegateInfo("ps:alpha",(char *) NULL,exception);
  if (delegate_info == (const DelegateInfo *) NULL)
    {
      (void) RelinquishUniqueFileResource(postscript_filename);
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  density=AcquireString("");
  options=AcquireString("");
  (void) FormatLocaleString(density,MaxTextExtent,"%gx%g",resolution.x,
    resolution.y);
  (void) FormatLocaleString(options,MaxTextExtent,"-g%.20gx%.20g ",(double)
    page.width,(double) page.height);
  read_info=CloneImageInfo(image_info);
  *read_info->magick='\0';
  if (read_info->number_scenes != 0)
    {
      char
        pages[MaxTextExtent];

      (void) FormatLocaleString(pages,MaxTextExtent,"-dFirstPage=%.20g "
        "-dLastPage=%.20g ",(double) read_info->scene+1,(double)
        (read_info->scene+read_info->number_scenes));
      (void) ConcatenateMagickString(options,pages,MaxTextExtent);
      read_info->number_scenes=0;
      if (read_info->scenes != (char *) NULL)
        *read_info->scenes='\0';
    }
  if (*image_info->magick == 'E')
    {
      option=GetImageOption(image_info,"eps:use-cropbox");
      if ((option == (const char *) NULL) ||
          (IsStringTrue(option) != MagickFalse))
        (void) ConcatenateMagickString(options,"-dEPSCrop ",MaxTextExtent);
      if (fitPage != MagickFalse)
        (void) ConcatenateMagickString(options,"-dEPSFitPage ",MaxTextExtent);
    }
  (void) CopyMagickString(filename,read_info->filename,MaxTextExtent);
  (void) AcquireUniqueFilename(filename);
  (void) RelinquishUniqueFileResource(filename);
  (void) ConcatenateMagickString(filename,"%d",MaxTextExtent);
  (void) FormatLocaleString(command,MaxTextExtent,
    GetDelegateCommands(delegate_info),
    read_info->antialias != MagickFalse ? 4 : 1,
    read_info->antialias != MagickFalse ? 4 : 1,density,options,filename,
    postscript_filename,input_filename);
  options=DestroyString(options);
  density=DestroyString(density);
  *message='\0';
  status=InvokePostscriptDelegate(read_info->verbose,command,message,exception);
  (void) InterpretImageFilename(image_info,image,filename,1,
    read_info->filename);
  if ((status == MagickFalse) ||
      (IsPostscriptRendered(read_info->filename) == MagickFalse))
    {
      (void) ConcatenateMagickString(command," -c showpage",MaxTextExtent);
      status=InvokePostscriptDelegate(read_info->verbose,command,message,
        exception);
    }
  (void) RelinquishUniqueFileResource(postscript_filename);
  (void) RelinquishUniqueFileResource(input_filename);
  postscript_image=(Image *) NULL;
  if (status == MagickFalse)
    for (i=1; ; i++)
    {
      (void) InterpretImageFilename(image_info,image,filename,(int) i,
        read_info->filename);
      if (IsPostscriptRendered(read_info->filename) == MagickFalse)
        break;
      (void) RelinquishUniqueFileResource(read_info->filename);
    }
  else
    for (i=1; ; i++)
    {
      (void) InterpretImageFilename(image_info,image,filename,(int) i,
        read_info->filename);
      if (IsPostscriptRendered(read_info->filename) == MagickFalse)
        break;
      read_info->blob=NULL;
      read_info->length=0;
      next=ReadImage(read_info,exception);
      (void) RelinquishUniqueFileResource(read_info->filename);
      if (next == (Image *) NULL)
        break;
      AppendImageToList(&postscript_image,next);
    }
  (void) RelinquishUniqueFileResource(read_info->filename);
  read_info=DestroyImageInfo(read_info);
  if (postscript_image == (Image *) NULL)
    {
      if (*message != '\0')
        (void) ThrowMagickException(exception,GetMagickModule(),DelegateError,
          "PostscriptDelegateFailed","`%s'",message);
      image=DestroyImageList(image);
      return((Image *) NULL);
    }
  if (LocaleCompare(postscript_image->magick,"BMP") == 0)
    {
      Image
        *cmyk_image;

      cmyk_image=ConsolidateCMYKImages(postscript_image,exception);
      if (cmyk_image != (Image *) NULL)
        {
          postscript_image=DestroyImageList(postscript_image);
          postscript_image=cmyk_image;
        }
    }
  if (image_info->number_scenes != 0)
    {
      Image
        *clone_image;

      register ssize_t
        i;

      /*
        Add place holder images to meet the subimage specification requirement.
      */
      for (i=0; i < (ssize_t) image_info->scene; i++)
      {
        clone_image=CloneImage(postscript_image,1,1,MagickTrue,exception);
        if (clone_image != (Image *) NULL)
          PrependImageToList(&postscript_image,clone_image);
      }
    }
  do
  {
    (void) CopyMagickString(postscript_image->filename,filename,MaxTextExtent);
    (void) CopyMagickString(postscript_image->magick,image->magick,
      MaxTextExtent);
    if (columns != 0)
      postscript_image->magick_columns=columns;
    if (rows != 0)
      postscript_image->magick_rows=rows;
    postscript_image->page=page;
    (void) CloneImageProfiles(postscript_image,image);
    (void) CloneImageProperties(postscript_image,image);
    next=SyncNextImageInList(postscript_image);
    if (next != (Image *) NULL)
      postscript_image=next;
  } while (next != (Image *) NULL);
  image=DestroyImageList(image);
  scene=0;
  for (next=GetFirstImageInList(postscript_image); next != (Image *) NULL; )
  {
    next->scene=scene++;
    next=GetNextImageInList(next);
  }
  return(GetFirstImageInList(postscript_image));
}