validate incoming payload before resuming epoch.

microsoft · Apr 28, 2021 · 5ac18c2 · 5ac18c2
1 parent a31b52b
commit 5ac18c2
Showing 1 changed file with 17 additions and 5 deletions.
diff --git a/cs/src/core/Index/FasterLog/FasterLog.cs b/cs/src/core/Index/FasterLog/FasterLog.cs
@@ -245,11 +245,13 @@ public long Enqueue(IReadOnlySpanBatch readOnlySpanBatch)
         public unsafe bool TryEnqueue(byte[] entry, out long logicalAddress)
         {
             logicalAddress = 0;
+            var length = entry.Length;
+            int allocatedLength = headerSize + Align(length);
+            ValidateAllocatedLength(allocatedLength);
 
             epoch.Resume();
 
-            var length = entry.Length;
-            logicalAddress = allocator.TryAllocateRetryNow(headerSize + Align(length));
+            logicalAddress = allocator.TryAllocateRetryNow(allocatedLength);
             if (logicalAddress == 0)
             {
                 epoch.Suspend();
@@ -274,11 +276,13 @@ public unsafe bool TryEnqueue(byte[] entry, out long logicalAddress)
         public unsafe bool TryEnqueue(ReadOnlySpan<byte> entry, out long logicalAddress)
         {
             logicalAddress = 0;
+            var length = entry.Length;
+            int allocatedLength = headerSize + Align(length);
+            ValidateAllocatedLength(allocatedLength);
 
             epoch.Resume();
 
-            var length = entry.Length;
-            logicalAddress = allocator.TryAllocateRetryNow(headerSize + Align(length));
+            logicalAddress = allocator.TryAllocateRetryNow(allocatedLength);
             if (logicalAddress == 0)
             {
                 epoch.Suspend();
@@ -1111,8 +1115,9 @@ private unsafe bool TryAppend(IReadOnlySpanBatch readOnlySpanBatch, out long log
                 allocatedLength += Align(readOnlySpanBatch.Get(i).Length) + headerSize;
             }
 
-            epoch.Resume();
+            ValidateAllocatedLength(allocatedLength);
 
+            epoch.Resume();
             logicalAddress = allocator.TryAllocateRetryNow(allocatedLength);
             if (logicalAddress == 0)
             {
@@ -1303,5 +1308,12 @@ private unsafe void SetHeader(int length, byte* dest)
                 *(ulong*)dest = Utility.XorBytes(dest + 8, length + 4);
             }
         }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private void ValidateAllocatedLength(int numSlots)
+        {
+            if (numSlots > allocator.PageSize)
+                throw new FasterException("Entry does not fit on page");
+        }
     }
 }