bugfix: _datum_heap_read() handler may be called on misaligned address

issue is reported at heterodb#719
charliettxx · Jan 27, 2024 · 325b6b4 · 325b6b4
1 parent 3bd4304
commit 325b6b4
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Showing 4 changed files with 29 additions and 9 deletions.
diff --git a/src/xpu_basetype.cu b/src/xpu_basetype.cu
@@ -152,7 +152,7 @@ PGSTROM_SQLTYPE_OPERATORS(bool,true,1,sizeof(bool));
 		xpu_##NAME##_t *result = (xpu_##NAME##_t *)__result;			\
 																		\
 		result->expr_ops = &xpu_##NAME##_ops;							\
-		result->value = *((const BASETYPE *)addr);						\
+		__FetchStore(result->value, (const BASETYPE *)addr);			\
 		return true;													\
 	}																	\
 	STATIC_FUNCTION(bool)												\

diff --git a/src/xpu_common.h b/src/xpu_common.h
@@ -193,27 +193,47 @@ __runtime_file_name(const char *path)
 #define __FILE_NAME__	__runtime_file_name(__FILE__)
 #endif
 
-#ifdef __CUDACC__
+#ifdef __cplusplus
 template <typename T>
 INLINE_FUNCTION(T)
 __Fetch(const T *ptr)
 {
 	T	temp;
 
+	if ((sizeof(T) & (sizeof(T)-1)) == 0 &&
+		(((uintptr_t)ptr) & (sizeof(T)-1)) == 0)
+	{
+		return *ptr;
+	}
 	memcpy(&temp, ptr, sizeof(T));
-
 	return temp;
 }
 
+template <typename T>
+INLINE_FUNCTION(void)
+__FetchStore(T &dest, const T *ptr)
+{
+	if ((sizeof(T) & (sizeof(T)-1)) == 0 &&
+		(((uintptr_t)ptr) & (sizeof(T)-1)) == 0)
+	{
+		dest = *ptr;
+	}
+	else
+	{
+		memcpy(&dest, ptr, sizeof(T));
+	}
+}
+
 template <typename T>
 INLINE_FUNCTION(T)
 __volatileRead(const volatile T *ptr)
 {
 	return *ptr;
 }
 
-#else
+#else	/* __cplusplus */
 #define __Fetch(PTR)			(*(PTR))
+#define __FetchStore(DEST,PTR)	do { (DEST) = *(PTR); } while(0)
 #define __volatileRead(PTR)		(*(PTR))
 #endif
 

diff --git a/src/xpu_misclib.cu b/src/xpu_misclib.cu
@@ -536,7 +536,7 @@ xpu_money_datum_heap_read(kern_context *kcxt,
 	xpu_money_t *result = (xpu_money_t *)__result;
 
 	result->expr_ops = &xpu_money_ops;
-	result->value = *((Cash *)addr);
+	__FetchStore(result->value, (Cash *)addr);
 	return true;
 }
 

diff --git a/src/xpu_timelib.cu b/src/xpu_timelib.cu
@@ -68,7 +68,7 @@ xpu_date_datum_heap_read(kern_context *kcxt,
 	xpu_date_t *result = (xpu_date_t *)__result;
 
 	result->expr_ops = &xpu_date_ops;
-	result->value = *((const DateADT *)addr);
+	__FetchStore(result->value, (const DateADT *)addr);
 	return true;
 }
 
@@ -224,7 +224,7 @@ xpu_time_datum_heap_read(kern_context *kcxt,
 	xpu_time_t *result = (xpu_time_t *)__result;
 
 	result->expr_ops = &xpu_time_ops;
-	result->value = *((const TimeADT *)addr);
+	__FetchStore(result->value, (const TimeADT *)addr);
 	return true;
 }
 
@@ -517,7 +517,7 @@ xpu_timestamp_datum_heap_read(kern_context *kcxt,
 	xpu_timestamp_t *result = (xpu_timestamp_t *)__result;
 
 	result->expr_ops = &xpu_timestamp_ops;
-	result->value = *((int64_t *)addr);
+	__FetchStore(result->value, (int64_t *)addr);
 	return true;
 }
 
@@ -697,7 +697,7 @@ xpu_timestamptz_datum_heap_read(kern_context *kcxt,
 	xpu_timestamptz_t *result = (xpu_timestamptz_t *)__result;
 
 	result->expr_ops = &xpu_timestamptz_ops;
-	result->value = *((const TimestampTz *)addr);
+	__FetchStore(result->value, (const TimestampTz *)addr);
 	return true;
 }