Negative Length in ReadOnlySequence

[kuda1978]

Description

In some cases Length of ReadOnlySequence was Negative.

Test for reproduce problem: ReadOnlySequenceTests.cs

Configuration

.Net SDK: 5.0.400, 6.0.100-preview.7.21379.14

Solution

In file ~\dotnet\runtime\src\libraries\System.Memory\src\System\Buffers\ReadOnlySequence.cs replace folowing string:

public ReadOnlySequence(ReadOnlyMemory<T> memory)
{
    if (MemoryMarshal.TryGetMemoryManager(memory, out MemoryManager<T>? manager, out int index, out int length))
    {
        ...
        _endInteger = index + length;

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Issue Details

---

Description

In some cases Length of ReadOnlySequence was Negative.

Test for reproduce problem: ReadOnlySequenceTests.cs

Configuration

.Net SDK: 5.0.400, 6.0.100-preview.7.21379.14

Author:	kuda1978
Assignees:	-
Labels:	area-System.Memory, untriaged
Milestone:	-

[adamsitnik]

I've confirmed that it's reproducible on 3.1, 5.0 and 6.0 and I am 99.9% sure it's a bug. I am on it.