Improper locking in Linux kernel - CVE-2026-98223

Vulnerability identifier: #VU153794

CSH Severity: Low

CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98223

CWE-ID: CWE-667

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to trigger a sleeping-in-atomic warning in the kernel.

The vulnerability exists due to a potentially sleeping lock acquisition in non-preemptible context in mm/filemap.c when invalidating mapped dropbehind folios after writeback completes. A local user can trigger fault-around mapping of a dropbehind folio to trigger a sleeping-in-atomic warning in the kernel.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17

• https://git.kernel.org/stable/c/2897601dffe576fcd87a4259102f41f7fb0cbfc8
• https://git.kernel.org/stable/c/77c0fade37c80e8aa16ac048a9828249055e3f66
• https://git.kernel.org/stable/c/848d2ce2fce15fbdc083fbf9691bfa72911033c4

• Improper locking in Linux kernel mm
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more