Revert "Tiff decoding robustness improvements (#2550)"

(accidental push to unprotected branch)

Author: antonfirsov

src/ImageSharp/Compression/Zlib/ZlibInflateStream.cs

@@ -161,25 +161,29 @@ public override int Read(byte[] buffer, int offset, int count)
             bytesToRead = Math.Min(count - totalBytesRead, this.currentDataRemaining);
             this.currentDataRemaining -= bytesToRead;
             bytesRead = this.innerStream.Read(buffer, offset, bytesToRead);
-            if (bytesRead == 0)
-            {
-                return totalBytesRead;
-            }
-
             totalBytesRead += bytesRead;
         }
 
         return totalBytesRead;
     }
 
     /// <inheritdoc/>
-    public override long Seek(long offset, SeekOrigin origin) => throw new NotSupportedException();
+    public override long Seek(long offset, SeekOrigin origin)
+    {
+        throw new NotSupportedException();
+    }
 
     /// <inheritdoc/>
-    public override void SetLength(long value) => throw new NotSupportedException();
+    public override void SetLength(long value)
+    {
+        throw new NotSupportedException();
+    }
 
     /// <inheritdoc/>
-    public override void Write(byte[] buffer, int offset, int count) => throw new NotSupportedException();
+    public override void Write(byte[] buffer, int offset, int count)
+    {
+        throw new NotSupportedException();
+    }
 
     /// <inheritdoc/>
     protected override void Dispose(bool disposing)
@@ -242,17 +246,22 @@ private bool InitializeInflateStream(bool isCriticalChunk)
                     // CINFO is not defined in this specification for CM not equal to 8.
                     throw new ImageFormatException($"Invalid window size for ZLIB header: cinfo={cinfo}");
                 }
-
-                return false;
+                else
+                {
+                    return false;
+                }
             }
         }
-        else if (isCriticalChunk)
-        {
-            throw new ImageFormatException($"Bad method for ZLIB header: cmf={cmf}");
-        }
         else
         {
-            return false;
+            if (isCriticalChunk)
+            {
+                throw new ImageFormatException($"Bad method for ZLIB header: cmf={cmf}");
+            }
+            else
+            {
+                return false;
+            }
         }
 
         // The preset dictionary.
@@ -261,11 +270,7 @@ private bool InitializeInflateStream(bool isCriticalChunk)
         {
             // We don't need this for inflate so simply skip by the next four bytes.
             // https://tools.ietf.org/html/rfc1950#page-6
-            if (this.innerStream.Read(ChecksumBuffer, 0, 4) != 4)
-            {
-                return false;
-            }
-
+            this.innerStream.Read(ChecksumBuffer, 0, 4);
             this.currentDataRemaining -= 4;
         }
 

src/ImageSharp/Formats/Tiff/Ifd/DirectoryReader.cs

@@ -40,7 +40,7 @@ public DirectoryReader(Stream stream, MemoryAllocator allocator)
     public IList<ExifProfile> Read()
     {
         this.ByteOrder = ReadByteOrder(this.stream);
-        HeaderReader headerReader = new(this.stream, this.ByteOrder);
+        var headerReader = new HeaderReader(this.stream, this.ByteOrder);
         headerReader.ReadFileHeader();
 
         this.nextIfdOffset = headerReader.FirstIfdOffset;
@@ -52,12 +52,7 @@ public IList<ExifProfile> Read()
     private static ByteOrder ReadByteOrder(Stream stream)
     {
         Span<byte> headerBytes = stackalloc byte[2];
-
-        if (stream.Read(headerBytes) != 2)
-        {
-            throw TiffThrowHelper.ThrowInvalidHeader();
-        }
-
+        stream.Read(headerBytes);
         if (headerBytes[0] == TiffConstants.ByteOrderLittleEndian && headerBytes[1] == TiffConstants.ByteOrderLittleEndian)
         {
             return ByteOrder.LittleEndian;
@@ -73,10 +68,10 @@ private static ByteOrder ReadByteOrder(Stream stream)
 
     private IList<ExifProfile> ReadIfds(bool isBigTiff)
     {
-        List<EntryReader> readers = new();
+        var readers = new List<EntryReader>();
         while (this.nextIfdOffset != 0 && this.nextIfdOffset < (ulong)this.stream.Length)
         {
-            EntryReader reader = new(this.stream, this.ByteOrder, this.allocator);
+            var reader = new EntryReader(this.stream, this.ByteOrder, this.allocator);
             reader.ReadTags(isBigTiff, this.nextIfdOffset);
 
             if (reader.BigValues.Count > 0)
@@ -90,11 +85,6 @@ private IList<ExifProfile> ReadIfds(bool isBigTiff)
                 }
             }
 
-            if (this.nextIfdOffset >= reader.NextIfdOffset && reader.NextIfdOffset != 0)
-            {
-                TiffThrowHelper.ThrowImageFormatException("TIFF image contains circular directory offsets");
-            }
-
             this.nextIfdOffset = reader.NextIfdOffset;
             readers.Add(reader);
 
@@ -104,11 +94,11 @@ private IList<ExifProfile> ReadIfds(bool isBigTiff)
             }
         }
 
-        List<ExifProfile> list = new(readers.Count);
+        var list = new List<ExifProfile>(readers.Count);
         foreach (EntryReader reader in readers)
         {
             reader.ReadBigValues();
-            ExifProfile profile = new(reader.Values, reader.InvalidTags);
+            var profile = new ExifProfile(reader.Values, reader.InvalidTags);
             list.Add(profile);
         }
 

tests/ImageSharp.Tests/Formats/Tiff/TiffDecoderTests.cs

@@ -3,7 +3,6 @@
 
 // ReSharper disable InconsistentNaming
 using System.Runtime.InteropServices;
-using System.Runtime.Intrinsics.X86;
 using SixLabors.ImageSharp.Formats;
 using SixLabors.ImageSharp.Formats.Tiff;
 using SixLabors.ImageSharp.Metadata;
@@ -687,33 +686,6 @@ public void TiffDecoder_ThrowsException_WithTooManyDirectories<TPixel>(TestImage
     public void TiffDecoder_CanDecode_Fax4CompressedWithStrips<TPixel>(TestImageProvider<TPixel> provider)
         where TPixel : unmanaged, IPixel<TPixel> => TestTiffDecoder(provider);
 
-
-    [Theory]
-    [WithFile(JpegCompressedGray0000539558, PixelTypes.Rgba32)]
-    public void TiffDecoder_ThrowsException_WithCircular_IFD_Offsets<TPixel>(TestImageProvider<TPixel> provider)
-        where TPixel : unmanaged, IPixel<TPixel>
-        => Assert.Throws<ImageFormatException>(
-            () =>
-            {
-                using (provider.GetImage(TiffDecoder.Instance))
-                {
-                }
-            });
-
-    [Theory]
-    [WithFile(Tiled0000023664, PixelTypes.Rgba32)]
-    public void TiffDecoder_CanDecode_TiledWithBadZlib<TPixel>(TestImageProvider<TPixel> provider)
-        where TPixel : unmanaged, IPixel<TPixel>
-    {
-        using Image<TPixel> image = provider.GetImage(TiffDecoder.Instance);
-
-        // ImageMagick cannot decode this image.
-        image.DebugSave(provider);
-        image.CompareToReferenceOutput(
-            ImageComparer.Exact,
-            provider,
-            appendPixelTypeToFileName: false);
-    }
     [Theory]
     [WithFileCollection(nameof(MultiframeTestImages), PixelTypes.Rgba32)]
     public void DecodeMultiframe<TPixel>(TestImageProvider<TPixel> provider)

tests/ImageSharp.Tests/TestImages.cs

@@ -965,8 +965,6 @@ public static class Tiff
         public const string Issues2123 = "Tiff/Issues/Issue2123.tiff";
         public const string Issues2149 = "Tiff/Issues/Group4CompressionWithStrips.tiff";
         public const string Issues2255 = "Tiff/Issues/Issue2255.png";
-        public const string JpegCompressedGray0000539558 = "Tiff/Issues/JpegCompressedGray-0000539558.tiff";
-        public const string Tiled0000023664 = "Tiff/Issues/tiled-0000023664.tiff";
 
         public const string SmallRgbDeflate = "Tiff/rgb_small_deflate.tiff";
         public const string SmallRgbLzw = "Tiff/rgb_small_lzw.tiff";