CVE-2026-98445: xfs: don't let memory failures leak blocks and kill repairs

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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

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

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

xfs: don't let memory failures leak blocks and kill repairs

LOLLM complains that a memory allocation failure in
xrep_newbt_add_blocks results in online repair leaking blocks that were
previously allocated to write a new btree, but the problem is worse than
that -- a limitation of the codebase is that the callers cannot undo the
transaction /and/ return the error -- either you undo all changes and
commit the transaction, or you error out and the filesystem goes down.

However, the new btree space reservation object isn't that big (~48
bytes).  Let's just do a NOFAIL allocation and the problem goes away.

The Linux kernel CVE team has assigned CVE-2026-98445 to this issue.


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

	Issue introduced in 6.8 with commit be408417630427984a1fddd069f30b245793234c and fixed in 6.12.113 with commit 3380151cf0ce8ad0c1d356fed51e4b69e1d28e50
	Issue introduced in 6.8 with commit be408417630427984a1fddd069f30b245793234c and fixed in 6.18.56 with commit b15c79fca28060fd9c7e77f2c3ebc4ba023974e8
	Issue introduced in 6.8 with commit be408417630427984a1fddd069f30b245793234c and fixed in 7.2.9 with commit 0e0d3372a84029da1768c7a4c4601484af5b58a2
	Issue introduced in 6.8 with commit be408417630427984a1fddd069f30b245793234c and fixed in 7.3-rc5 with commit ab1c416d2377cdc16123ef521aac4da1c468c3d4

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-2026-98445
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:
	fs/xfs/scrub/newbt.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/3380151cf0ce8ad0c1d356fed51e4b69e1d28e50
	https://git.kernel.org/stable/c/b15c79fca28060fd9c7e77f2c3ebc4ba023974e8
	https://git.kernel.org/stable/c/0e0d3372a84029da1768c7a4c4601484af5b58a2
	https://git.kernel.org/stable/c/ab1c416d2377cdc16123ef521aac4da1c468c3d4