Avoid some unsigned integer overflow errors. In some cases, the code intends overflow to occur and relies on the defined behavior for unsigned integer wraparound; detection has been switched off in these cases. In other cases, the overflow was undesired; these cases have been fixed to avoid the overflow.

7 files changed, 42 insertions, 13 deletions

diff --git a/source/dng_fingerprint.cpp b/source/dng_fingerprint.cpp
index 5256873..8aa2673 100644
--- a/source/dng_fingerprint.cpp
+++ b/source/dng_fingerprint.cpp
@@ -448,6 +448,9 @@ void dng_md5_printer::Decode (uint32 *output,
 

 // MD5 basic transformation. Transforms state based on block.

 

+#if defined(__clang__)

+__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 void dng_md5_printer::MD5Transform (uint32 state [4],

 								    const uint8 block [64])

 	{

diff --git a/source/dng_fingerprint.h b/source/dng_fingerprint.h
index b8c5cfb..58c0762 100644
--- a/source/dng_fingerprint.h
+++ b/source/dng_fingerprint.h
@@ -225,7 +225,10 @@ class dng_md5_printer
 			}

 			

 		// FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.

-		

+	

+#if defined(__clang__)

+		__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 		static inline void FF (uint32 &a,

 							   uint32 b,

 							   uint32 c,

@@ -239,6 +242,9 @@ class dng_md5_printer
 			a += b;

 			}

 

+#if defined(__clang__)

+		__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 		static inline void GG (uint32 &a,

 							   uint32 b,

 							   uint32 c,

@@ -252,6 +258,9 @@ class dng_md5_printer
 			a += b;

 			}

 

+#if defined(__clang__)

+		__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 		static inline void HH (uint32 &a,

 							   uint32 b,

 							   uint32 c,

@@ -265,6 +274,9 @@ class dng_md5_printer
 			a += b;

 			}

 

+#if defined(__clang__)

+		__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 		static inline void II (uint32 &a,

 							   uint32 b,

 							   uint32 c,

diff --git a/source/dng_info.cpp b/source/dng_info.cpp
index 35bec3c..e2d72a3 100644
--- a/source/dng_info.cpp
+++ b/source/dng_info.cpp
@@ -1521,7 +1521,7 @@ void dng_info::ParseDNGPrivateData (dng_host &host,
 			#endif

 				

 			uint16 order_mark = stream.Get_uint16 ();

-			uint64 old_offset = stream.Get_uint32 ();

+			int64 old_offset = stream.Get_uint32 ();

 

 			uint32 tempSize = section_count - 6;

 			

diff --git a/source/dng_mosaic_info.cpp b/source/dng_mosaic_info.cpp
index c3b116e..6d49894 100644
--- a/source/dng_mosaic_info.cpp
+++ b/source/dng_mosaic_info.cpp
@@ -286,14 +286,20 @@ class dng_bilinear_pattern
 		

 	private:

 	

+#if defined(__clang__)

+__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif

 		uint32 DeltaRow (uint32 row, int32 delta)

 			{

-			return (row + fPatRows + delta) % fPatRows;

+			return (row + fPatRows + (uint32) delta) % fPatRows;

 			}

-			

+		

+#if defined(__clang__)

+__attribute__((no_sanitize("unsigned-integer-overflow")))

+#endif	

 		uint32 DeltaCol (uint32 col, int32 delta)

 			{

-			return (col + fPatCols + delta) % fPatCols;

+			return (col + fPatCols + (uint32) delta) % fPatCols;

 			}

 	

 		real32 LinearWeight1 (int32 d1, int32 d2)

diff --git a/source/dng_reference.cpp b/source/dng_reference.cpp
index 3feb195..156726d 100644
--- a/source/dng_reference.cpp
+++ b/source/dng_reference.cpp
@@ -1419,12 +1419,12 @@ void RefBaselineHueSatMap (const real32 *sPtrR,
 					  valDivisions);

 					  

 	real32 hScale = (hueDivisions < 2) ? 0.0f : (hueDivisions * (1.0f / 6.0f));

-	real32 sScale = (real32) (satDivisions - 1);

-	real32 vScale = (real32) (valDivisions - 1);

+	real32 sScale = (real32) ((int32) satDivisions - 1);

+	real32 vScale = (real32) ((int32) valDivisions - 1);

 		

-	int32 maxHueIndex0 = hueDivisions - 1;

-	int32 maxSatIndex0 = satDivisions - 2;

-	int32 maxValIndex0 = valDivisions - 2;

+	int32 maxHueIndex0 = (int32) hueDivisions - 1;

+	int32 maxSatIndex0 = (int32) satDivisions - 2;

+	int32 maxValIndex0 = (int32) valDivisions - 2;

 

 	const bool hasEncodeTable = ((encodeTable != NULL) && (encodeTable->Table () != NULL));

 	const bool hasDecodeTable = ((decodeTable != NULL) && (decodeTable->Table () != NULL));

diff --git a/source/dng_resample.cpp b/source/dng_resample.cpp
index 3d98b7f..122bff9 100644
--- a/source/dng_resample.cpp
+++ b/source/dng_resample.cpp
@@ -231,7 +231,7 @@ void dng_resample_weights::Initialize (real64 scale,
 			for (j = 0; j < width; j++)
 				{
 				
-				int32 k = j - fRadius + 1;
+				int32 k = (int32) j - (int32) fRadius + 1;
 				
 				real64 x = (k - fract) * scale;
 				
@@ -393,13 +393,13 @@ void dng_resample_weights_2d::Initialize (const dng_resample_function &kernel,
 				for (uint32 i = 0; i < width; i++)
 					{
 		
-					int32 yInt = ((int32) i) - fRadius + 1;
+					int32 yInt = ((int32) i) - (int32) fRadius + 1;
 					real64 yPos = yInt - yFract;
 
 					for (uint32 j = 0; j < width; j++)
 						{
 				
-						int32 xInt = ((int32) j) - fRadius + 1;
+						int32 xInt = ((int32) j) - (int32) fRadius + 1;
 						real64 xPos = xInt - xFract;
 
 						#if 0
diff --git a/source/dng_utils.h b/source/dng_utils.h
index 99b9610..d6b79c6 100644
--- a/source/dng_utils.h
+++ b/source/dng_utils.h
@@ -26,6 +26,11 @@
 
 /*****************************************************************************/
 
+// The unsigned integer overflow is intended here since a wrap around is used to
+// calculate the abs() in the branchless version.
+#if defined(__clang__)
+__attribute__((no_sanitize("unsigned-integer-overflow")))
+#endif
 inline uint32 Abs_int32 (int32 x)
 	{
 	
@@ -1130,6 +1135,9 @@ inline int32 Mulsh86 (int32 x, int32 y)
 // This is the ACM standard 30 bit generator:
 // x' = (x * 16807) mod 2^31-1
 
+#if defined(__clang__)
+__attribute__((no_sanitize("unsigned-integer-overflow")))
+#endif
 inline uint32 DNG_Random (uint32 seed)
 	{