CVE-2026-74299: RDMA/core: Fix FRMR aging push to queue error flow

CVE-2026-74299: RDMA/core: Fix FRMR aging push to queue error flow

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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

RDMA/core: Fix FRMR aging push to queue error flow

Aging pools with pinned handles requires moving handles from the
active queue to a non-empty inactive queue that might fail on new page
allocation, we are currently not handling the fault and leaking any mkey
that fails the push.

Fix by Introducing push_queue_to_queue_locked() that fills the
destination's partial tail page from the source and then splices the
remaining source pages onto the destination, performing no allocation.

Replace the per-handle move loop in age_pinned_pool() and the
open-coded splice in pool_aging_work() with calls to the helper.
As the helper cannot fail under memory pressure, removing a class of
GFP_ATOMIC allocations under the pool lock and simplifying the error
flow.

The Linux kernel CVE team has assigned CVE-2026-74299 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 7.1 with commit 020d189d16a62ed56115cce7e255459cf0eeb4e6 and fixed in 7.1.5 with commit edf133d28fc43f7f8b0da43a8d5b93fdf8073d35
	Issue introduced in 7.1 with commit 020d189d16a62ed56115cce7e255459cf0eeb4e6 and fixed in 7.2-rc1 with commit c6936506ed556ce3ccad36ab999baf2764dd7d25

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-74299
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/infiniband/core/frmr_pools.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/edf133d28fc43f7f8b0da43a8d5b93fdf8073d35
	https://git.kernel.org/stable/c/c6936506ed556ce3ccad36ab999baf2764dd7d25