CVE-2023-52672

In the Linux kernel, the following vulnerability has been resolved:

pipe: wakeup wr_wait after setting max_usage

Commit c73be61cede5 (pipe: Add general notification queue support) a regression was introduced that would lock up resized pipes under certain conditions. See the reproducer in [1].

The commit resizing the pipe ring size was moved to a different function, doing that moved the wakeup for pipe->wr_wait before actually raising pipe->max_usage. If a pipe was full before the resize occured it would result in the wakeup never actually triggering pipe_write.

Set @max_usage and @nr_accounted before waking writers if this isnt a watch queue.

[Christian Brauner brauner@kernel.org: rewrite to account for watch queues]

Weakness

The product does not properly control the allocation and maintenance of a limited resource.

Affected Software

Potential Mitigations

• Mitigation of resource exhaustion attacks requires that the target system either:

• The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.

• The second solution is simply difficult to effectively institute – and even when properly done, it does not provide a full solution. It simply makes the attack require more resources on the part of the attacker.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/147.html
• https://cwe.mitre.org/data/definitions/227.html
• https://cwe.mitre.org/data/definitions/492.html

References

• https://git.kernel.org/stable/c/162ae0e78bdabf84ef10c1293c4ed7865cb7d3c8
• https://git.kernel.org/stable/c/3efbd114b91525bb095b8ae046382197d92126b9
• https://git.kernel.org/stable/c/68e51bdb1194f11d3452525b99c98aff6f837b24
• https://git.kernel.org/stable/c/6fb70694f8d1ac34e45246b0ac988f025e1e5b55
• https://git.kernel.org/stable/c/b87a1229d8668fbc78ebd9ca0fc797a76001c60f
• https://git.kernel.org/stable/c/e95aada4cb93d42e25c30a0ef9eb2923d9711d4a
• https://git.kernel.org/stable/c/162ae0e78bdabf84ef10c1293c4ed7865cb7d3c8
• https://git.kernel.org/stable/c/3efbd114b91525bb095b8ae046382197d92126b9
• https://git.kernel.org/stable/c/68e51bdb1194f11d3452525b99c98aff6f837b24
• https://git.kernel.org/stable/c/6fb70694f8d1ac34e45246b0ac988f025e1e5b55
• https://git.kernel.org/stable/c/b87a1229d8668fbc78ebd9ca0fc797a76001c60f
• https://git.kernel.org/stable/c/e95aada4cb93d42e25c30a0ef9eb2923d9711d4a
• https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html