watch_queue: fix pipe accounting mismatch (CVE-2025-23138)

Summary

watch_queue: fix pipe accounting mismatch

Original description

The description as published by the source.

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

watch_queue: fix pipe accounting mismatch

Currently, watch_queue_set_size() modifies the pipe buffers charged to
user->pipe_bufs without updating the pipe->nr_accounted on the pipe
itself, due to the if (!pipe_has_watch_queue()) test in
pipe_resize_ring(). This means that when the pipe is ultimately freed,
we decrement user->pipe_bufs by something other than what than we had
charged to it, potentially leading to an underflow. This in turn can
cause subsequent too_many_pipe_buffers_soft() tests to fail with -EPERM.

To remedy this, explicitly account for the pipe usage in
watch_queue_set_size() to match the number set via account_pipe_buffers()

(It's unclear why watch_queue_set_size() does not update nr_accounted;
it may be due to intentional overprovisioning in watch_queue_set_size()?)

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.10.236"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.180"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.134"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.87"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.23"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.8.0"},{"fixed":"6.13.11"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.14.2"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

BellSoft Alpaquita BELL-CVE-2025-23138 linux-lts Fixed in: 6.1.134-r0
Debian DEBIAN-CVE-2025-23138 linux Fixed in: 5.10.237-1
Ubuntu UBUNTU-CVE-2025-23138 linux-hwe-edge

Summary

Original description

Affected packages

Fix status by distribution

References