File libexif-CVE-2020-0452.patch of Package libexif.23502

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File libexif-CVE-2020-0452.patch of Package libexif.23502

commit 9266d14b5ca4e29b970fa03272318e5f99386e06
Author: Marcus Meissner <marcus@jet.franken.de>
Date:   Thu Nov 5 09:50:08 2020 +0100

fixed a incorrect overflow check that could be optimized away.
    
    inspired by:
    https://android.googlesource.com/platform/external/libexif/+/8e7345f3bc0bad06ac369d6cbc1124c8ceaf7d4b
    
    https://source.android.com/security/bulletin/2020-11-01
    
    CVE-2020-0452

diff --git a/libexif/exif-entry.c b/libexif/exif-entry.c
index 3fc0ff9..4b866ce 100644
--- a/libexif/exif-entry.c
+++ b/libexif/exif-entry.c
@@ -1371,8 +1371,8 @@ exif_entry_get_value (ExifEntry *e, char *val, unsigned int maxlen)
 	{
 		unsigned char *utf16;
 
-		/* Sanity check the size to prevent overflow */
-		if (e->size+sizeof(uint16_t)+1 < e->size) break;
+		/* Sanity check the size to prevent overflow. Note EXIF files are 64kb at most. */
+		if (e->size >= 65536 - sizeof(uint16_t)*2) break;
 
 		/* The tag may not be U+0000-terminated , so make a local
 		   U+0000-terminated copy before converting it */

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File libexif-CVE-2020-0452.patch of Package libexif.23502

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