third bug fix: don't cast bytes to booleans

dotnet · Sep 12, 2024 · fcb3c8a · fcb3c8a
1 parent 61a9b14
commit fcb3c8a
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Showing 3 changed files with 41 additions and 1 deletion.
diff --git a/src/libraries/System.Formats.Nrbf/src/System/Formats/Nrbf/ArraySinglePrimitiveRecord.cs b/src/libraries/System.Formats.Nrbf/src/System/Formats/Nrbf/ArraySinglePrimitiveRecord.cs
@@ -163,6 +163,18 @@ internal static IReadOnlyList<T> DecodePrimitiveTypes(BinaryReader reader, int c
             }
         }
 
+        if (typeof(T) == typeof(bool))
+        {
+            // See DontCastBytesToBooleans test to see what could go wrong.
+            bool[] booleans = (bool[])(object)result;
+            for (int i = 0; i < booleans.Length; i++)
+            {
+                if (booleans[i]) // it can be any byte different than 0
+                {
+                    booleans[i] = true; // set it to 1 in explicit way
+                }
+            }
+        }
         return result;
     }
 

diff --git a/src/libraries/System.Formats.Nrbf/tests/ArraySinglePrimitiveRecordTests.cs b/src/libraries/System.Formats.Nrbf/tests/ArraySinglePrimitiveRecordTests.cs
@@ -3,6 +3,7 @@
 
 using System.Collections.Generic;
 using System.IO;
+using System.Text;
 using Xunit;
 
 namespace System.Formats.Nrbf.Tests;
@@ -24,6 +25,33 @@ public static IEnumerable<object[]> GetCanReadArrayOfAnySizeArgs()
         }
     }
 
+    [Fact]
+    public void DontCastBytesToBooleans()
+    {
+        using MemoryStream stream = new();
+        BinaryWriter writer = new(stream, Encoding.UTF8);
+
+        WriteSerializedStreamHeader(writer);
+        writer.Write((byte)SerializationRecordType.ArraySinglePrimitive);
+        writer.Write(1); // object ID
+        writer.Write(2); // length
+        writer.Write((byte)PrimitiveType.Boolean); // element type
+        writer.Write((byte)0x01);
+        writer.Write((byte)0x02);
+        writer.Write((byte)SerializationRecordType.MessageEnd);
+        stream.Position = 0;
+
+        SZArrayRecord<bool> serializationRecord = (SZArrayRecord<bool>)NrbfDecoder.Decode(stream);
+
+        bool[] bools = serializationRecord.GetArray();
+        bool a = bools[0];
+        Assert.True(a);
+        bool b = bools[1];
+        Assert.True(b);
+        bool c = a && b;
+        Assert.True(c);
+    }
+
     [Theory]
     [MemberData(nameof(GetCanReadArrayOfAnySizeArgs))]
     public void CanReadArrayOfAnySize_Bool(int size, bool canSeek) => Test<bool>(size, canSeek);

diff --git a/src/libraries/System.Formats.Nrbf/tests/AttackTests.cs b/src/libraries/System.Formats.Nrbf/tests/AttackTests.cs
@@ -154,7 +154,7 @@ public void ArraysOfBytesAreNotBeingPreAllocated()
         writer.Write((byte)SerializationRecordType.ArraySinglePrimitive);
         writer.Write(1); // object ID
         writer.Write(Array.MaxLength); // length
-        writer.Write((byte)2); // PrimitiveType.Byte
+        writer.Write((byte)PrimitiveType.Byte);
         writer.Write((byte)SerializationRecordType.MessageEnd);
 
         stream.Position = 0;