CVE-2026-89770: iomap: don't free integrity payload that doesn't exist

CVE-2026-89770: iomap: don't free integrity payload that doesn't exist

[Greg Kroah-Hartman]

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

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

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

iomap: don't free integrity payload that doesn't exist

fs_bio_integrity_alloc might not allocate a bio integrity payload if PI
verification is disabled on the block device.  Check for that case before
calling fs_bio_integrity_free in iomap_bio_read_folio_range_sync to
avoid a NULL pointer dereferences.

Make the branch cover the PI verification as well - while
fs_bio_integrity_verify works without an integrity payload, it requires
one to actually do useful work.

The Linux kernel CVE team has assigned CVE-2026-89770 to this issue.


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

	Issue introduced in 7.1 with commit 0b10a370529cbd7b918c1eef43d409e43d9e0b78 and fixed in 7.2.4 with commit 65651f1001aa3638909bc58c7b2b46160692757b
	Issue introduced in 7.1 with commit 0b10a370529cbd7b918c1eef43d409e43d9e0b78 and fixed in 7.3-rc1 with commit 8a8685b32c0718cc7b2cb4d6202e5a5b8e0a8e2d

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-2026-89770
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/iomap/bio.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/65651f1001aa3638909bc58c7b2b46160692757b
	https://git.kernel.org/stable/c/8a8685b32c0718cc7b2cb4d6202e5a5b8e0a8e2d