Update fuzz_exif.py

Tests/oss-fuzz/fuzz_exif.py

@@ -1,17 +1,11 @@
-# Enhanced Fuzz Target for Pillow: EXIF Metadata Fuzzing
-
-This fuzz target focuses on testing the EXIF metadata handling capabilities of Pillow, which is an area not specifically targeted by the existing fuzzers.
-
-```python
 #!/usr/bin/env python3
-
 # Copyright 2025 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
-#      http://www.apache.org/licenses/LICENSE-2.0
+#     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
@@ -19,90 +13,54 @@ This fuzz target focuses on testing the EXIF metadata handling capabilities of P
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import sys
+import io
+
 import atheris
 from atheris.import_hook import instrument_imports
 
 with instrument_imports():
-    import io
+    from PIL import ExifTags, Image
-    import sys
+
-    from PIL import Image, ExifTags
 
 def TestOneInput(data):
-    if len(data) < 10:  # Skip inputs that are too small
+    if len(data) < 10:
         return
 
     try:
-        # Create a BytesIO object from the fuzzer data
         image_io = io.BytesIO(data)
 
-        # Try to open the image
         with Image.open(image_io) as img:
-            # Test EXIF extraction
             try:
                 exif = img._getexif()
                 if exif:
-                    # Process EXIF data
                     for tag_id, value in exif.items():
-                        # Try to get the tag name
                         tag_name = ExifTags.TAGS.get(tag_id, tag_id)
-
+                        if tag_id == 34853:  # GPSInfo
-                        # Try to convert GPS info
-                        if tag_id == 34853:  # GPSInfo tag
                             for gps_tag, gps_value in value.items():
                                 gps_tag_name = ExifTags.GPSTAGS.get(gps_tag, gps_tag)
             except Exception:
-                # Catch exceptions from EXIF processing
                 pass
 
-            # Test thumbnail extraction from EXIF
             try:
-                if hasattr(img, 'getexif'):
+                if hasattr(img, "getexif"):
                     exif = img.getexif()
-                    if exif:
+                    if exif and hasattr(exif, "get_thumbnail"):
-                        # Try to extract thumbnail if present
+                        thumbnail = exif.get_thumbnail()
-                        if hasattr(exif, 'get_thumbnail'):
+                        if thumbnail:
-                            thumbnail = exif.get_thumbnail()
+                            thumb_img = Image.open(io.BytesIO(thumbnail))
-                            if thumbnail:
+                            thumb_img.load()
-                                # Try to open the thumbnail
-                                thumb_img = Image.open(io.BytesIO(thumbnail))
-                                thumb_img.load()
             except Exception:
-                # Catch exceptions from thumbnail extraction
                 pass
 
     except Exception:
-        # Catch all other exceptions
         pass
 
+
 def main():
     atheris.Setup(sys.argv, TestOneInput)
     atheris.Fuzz()
 
+
 if __name__ == "__main__":
     main()
-```
-
-## Features
-
-This fuzz target specifically tests:
-
-1. EXIF metadata extraction from images
-2. Processing of EXIF tags and values
-3. GPS information handling
-4. Thumbnail extraction from EXIF data
-
-## Integration
-
-To integrate this fuzz target:
-
-1. Save it as `fuzz_exif.py` in the `Tests/oss-fuzz/` directory
-2. Update the `build.sh` script to include this target in the build process
-3. Test locally to ensure it works correctly
-4. Submit as part of a pull request to the Pillow repository
-
-## Expected Benefits
-
-- Increased coverage of EXIF metadata handling code
-- Potential discovery of bugs in metadata parsing
-- Better handling of malformed EXIF data
-- Improved security for applications processing images with metadata