Skip to content

Add minimum remaining-data checks for fixed-size binary reads #125698

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
I-WAS-FUTURE wants to merge 1 commit into from
Closed

Add minimum remaining-data checks for fixed-size binary reads #125698

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
34 changes: 28 additions & 6 deletions src/libraries/System.Private.CoreLib/src/System/IO/BinaryReader.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -183,6 +183,22 @@ public virtual int Read()

public virtual byte ReadByte() => InternalReadByte();

[MethodImpl(MethodImplOptions.AggressiveInlining)]
private void EnsureCanRead(int byteCount)
{
ArgumentOutOfRangeException.ThrowIfNegative(byteCount);
ThrowIfDisposed();

if (_stream.CanSeek)
{
long remaining = _stream.Length - _stream.Position;
if (remaining < 0 || remaining < byteCount)
{
ThrowHelper.ThrowEndOfFileException();
}
}
}

[MethodImpl(MethodImplOptions.AggressiveInlining)] // Inlined to avoid some method call overhead with InternalRead.
private byte InternalReadByte()
{
Expand Down Expand Up @@ -256,6 +272,8 @@ public virtual string ReadString()
return string.Empty;
}

EnsureCanRead(stringLength);

Span<byte> charBytes = stackalloc byte[MaxCharBytesSize];

int currPos = 0;
Expand Down Expand Up @@ -446,7 +464,6 @@ public virtual byte[] ReadBytes(int count)

if (numRead != result.Length)
{
// Trim array. This should happen on EOF & possibly net streams.
result = result[..numRead];
}

Expand All @@ -466,6 +483,7 @@ public virtual byte[] ReadBytes(int count)
public virtual void ReadExactly(Span<byte> buffer)
{
ThrowIfDisposed();
EnsureCanRead(buffer.Length);
_stream.ReadExactly(buffer);
}

Expand All @@ -481,10 +499,8 @@ private ReadOnlySpan<byte> InternalRead(Span<byte> buffer)
}
else
{
ThrowIfDisposed();

EnsureCanRead(buffer.Length);
_stream.ReadExactly(buffer);

return buffer;
}
}
Expand Down Expand Up @@ -523,8 +539,14 @@ protected virtual void FillBuffer(int numBytes)
return;
}
byte[] buffer = ArrayPool<byte>.Shared.Rent(numBytes);
_stream.ReadExactly(buffer.AsSpan(0, numBytes));
ArrayPool<byte>.Shared.Return(buffer);
try
{
_stream.ReadExactly(buffer.AsSpan(0, numBytes));
}
finally
{
ArrayPool<byte>.Shared.Return(buffer);
}
break;
}
}
Expand Down
Loading