[release/7.0] Crash when region survives >2GB

src/coreclr/gc/env/gcenv.base.h

@@ -86,6 +86,7 @@ inline HRESULT HRESULT_FROM_WIN32(unsigned long x)
 #define CLR_E_GC_BAD_AFFINITY_CONFIG_FORMAT    0x8013200B
 #define CLR_E_GC_BAD_HARD_LIMIT                0x8013200D
 #define CLR_E_GC_LARGE_PAGE_MISSING_HARD_LIMIT 0x8013200E
+#define CLR_E_GC_BAD_REGION_SIZE               0x8013200F
 
 #define NOERROR                 0x0
 #define ERROR_TIMEOUT           1460

src/coreclr/gc/gc.cpp

@@ -31666,8 +31666,8 @@ bool gc_heap::should_sweep_in_plan (heap_segment* region)
         size_t basic_region_size = (size_t)1 << min_segment_size_shr;
         assert (heap_segment_gen_num (region) == heap_segment_plan_gen_num (region));
 
-        int surv_ratio = (int)(((double)heap_segment_survived (region) * 100.0) / (double)basic_region_size);
-        dprintf (2222, ("SSIP: region %Ix surv %Id / %Id = %d%%(%d)",
+        uint8_t surv_ratio = (uint8_t)(((double)heap_segment_survived (region) * 100.0) / (double)basic_region_size);
+        dprintf (2222, ("SSIP: region %p surv %hu / %zd = %d%%(%d)",
             heap_segment_mem (region),
             heap_segment_survived (region),
             basic_region_size,
@@ -45286,8 +45286,14 @@ HRESULT GCHeap::Initialize()
     gc_heap::enable_special_regions_p = (bool)GCConfig::GetGCEnableSpecialRegions();
     size_t gc_region_size = (size_t)GCConfig::GetGCRegionSize();
 
-    // Adjust GCRegionSize based on how large each heap would be, for smaller heaps we would 
-    // like to keep Region sizes small. We choose between 4, 2 and 1mb based on the calculations 
+    // Constraining the size of region size to be < 2 GB.       
+    if (gc_region_size >= MAX_REGION_SIZE) 
+    {
+        return CLR_E_GC_BAD_REGION_SIZE;
+    }
+
+    // Adjust GCRegionSize based on how large each heap would be, for smaller heaps we would
+    // like to keep Region sizes small. We choose between 4, 2 and 1mb based on the calculations
     // below (unless its configured explictly) such that there are at least 2 regions available
     // except for the smallest case. Now the lowest limit possible is 4mb. 
     if (gc_region_size == 0)

src/coreclr/gc/gcpriv.h

@@ -191,6 +191,10 @@ void GCLogConfig (const char *fmt, ... );
 
 #define MAX_NUM_BUCKETS (MAX_INDEX_POWER2 - MIN_INDEX_POWER2 + 1)
 
+#ifdef USE_REGIONS
+#define MAX_REGION_SIZE 0x80000000 
+#endif // USE_REGIONS
+
 #define MAX_NUM_FREE_SPACES 200
 #define MIN_NUM_FREE_SPACES 5
 

src/coreclr/inc/corerror.xml

@@ -2133,6 +2133,12 @@
 	<Comment>During a GC initialization, GC large page support requires hard limit settings.</Comment>
 </HRESULT>
 
+<HRESULT NumericValue="0x8013200F">
+	<SymbolicName>CLR_E_GC_BAD_REGION_SIZE</SymbolicName>
+	<Message>"GC Region Size must be less than 2GB."</Message>
+	<Comment>During a GC initialization, GC Region Size must be less than 2GB.</Comment>
+</HRESULT>
+
 <HRESULT NumericValue="E_ACCESSDENIED">
 	<SymbolicName>COR_E_UNAUTHORIZEDACCESS</SymbolicName>
 	<Comment> 0x80070005 // Access is denied.</Comment>

src/coreclr/pal/prebuilt/corerror/mscorurt.rc

@@ -301,5 +301,6 @@ BEGIN
 	MSG_FOR_URT_HR(CLR_E_GC_BAD_AFFINITY_CONFIG_FORMAT) "GCHeapAffinitizeRanges configuration string has invalid format."
 	MSG_FOR_URT_HR(CLR_E_GC_BAD_HARD_LIMIT) "GC heap hard limit configuration is invalid."
 	MSG_FOR_URT_HR(CLR_E_GC_LARGE_PAGE_MISSING_HARD_LIMIT) "GC large page support requires hard limit settings."
+	MSG_FOR_URT_HR(CLR_E_GC_BAD_REGION_SIZE) "GC Region Size must be less than 2GB."
 	MSG_FOR_URT_HR(COR_E_BADIMAGEFORMAT) "The format of a DLL or executable being loaded is invalid."
 END

src/coreclr/pal/prebuilt/inc/corerror.h

@@ -374,6 +374,7 @@
 #define CLR_E_GC_BAD_AFFINITY_CONFIG_FORMAT EMAKEHR(0x200b)
 #define CLR_E_GC_BAD_HARD_LIMIT EMAKEHR(0x200d)
 #define CLR_E_GC_LARGE_PAGE_MISSING_HARD_LIMIT EMAKEHR(0x200e)
+#define CLR_E_GC_BAD_REGION_SIZE EMAKEHR(0x200f)
 #define COR_E_UNAUTHORIZEDACCESS E_ACCESSDENIED
 #define COR_E_ARGUMENT E_INVALIDARG
 #define COR_E_INVALIDCAST E_NOINTERFACE