CVE-2026-98262

What the bug is

A user reported that commit 105c42566a55 ("ata: ahci: force 32-bit DMA for JMicron JMB582/JMB585") made the JMicron JMB585 unusable on his board. The failure is seen as soon as the ahci driver is probed, and booting with iommu=off does not solve the problem. Looking at the AHCI specification, PxCLBU and PxFBU are both read only '0' for HBAs that do not support 64-bit addressing. For HBAs that do support 64-bit addressing, the registers are read write, with a reset value that is Implementation Specific. When using the AHCI_HFLAG_32BIT_ONLY flag, the HBA does support 64-bit addressing, and a 32-bit DMA mask is set by simply clearing HOST_CAP_64. Thus, in this case, we need to explicitly clear the registers to 0.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/ata/libahci.c

What this is

LIBATA SUBSYSTEM (Serial and Parallel ATA drivers)MAINTAINERS section matched on drivers/ata/ · linux-ide@vger.kernel.org · Maintained

Kernel module

none to look for. The file would have gone into libahci, and Debian does not compile it into that module, so finding libahci in lsmod would say nothing about this CVE.

Check it on the machine

grep -wE 'CONFIG_AHCI_BRCM|CONFIG_AHCI_CEVA|CONFIG_AHCI_DA850|CONFIG_AHCI_DM816|CONFIG_AHCI_DWC|CONFIG_AHCI_IMX|CONFIG_AHCI_MTK|CONFIG_AHCI_MVEBU|CONFIG_AHCI_QORIQ|CONFIG_AHCI_ST|CONFIG_AHCI_SUNXI|CONFIG_AHCI_TEGRA|CONFIG_AHCI_XGENE|CONFIG_ATA|CONFIG_SATA_ACARD_AHCI|CONFIG_SATA_AHCI|CONFIG_SATA_AHCI_PLATFORM|CONFIG_SATA_AHCI_SEATTLE|CONFIG_SATA_HIGHBANK' /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

Show whether Debian builds this, per release

Debian does not build this code. In 4 releases below, every kernel flavour Debian publishes has the switch off, so the vulnerable file is compiled into no kernel binary Debian ships.

• bookworm, trixie, forky, sidn

n

not enabled on any flavour - this release does not build the code

Build switches

CONFIG_AHCI_BRCM, CONFIG_AHCI_CEVA, CONFIG_AHCI_DA850, CONFIG_AHCI_DM816, CONFIG_AHCI_DWC, CONFIG_AHCI_IMX, CONFIG_AHCI_MTK, CONFIG_AHCI_MVEBU, CONFIG_AHCI_QORIQ, CONFIG_AHCI_ST, CONFIG_AHCI_SUNXI, CONFIG_AHCI_TEGRA, CONFIG_AHCI_XGENE, CONFIG_ATA, CONFIG_SATA_ACARD_AHCI, CONFIG_SATA_AHCI, CONFIG_SATA_AHCI_PLATFORM, CONFIG_SATA_AHCI_SEATTLE, CONFIG_SATA_HIGHBANK

Reads as

all on means the file is compiled; any one off means it is not.

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-10-06 (13 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.18%, higher than 7.5% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/ata

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
2.6.22	5.10.271	0191c9ff23ef
2.6.22	5.15.222	8f510f68208a
2.6.22	6.1.189	4719424bb7cb
2.6.22	6.6.158	a5a8b4737f68
2.6.22	6.12.112	b28a17d4a9bb
2.6.22	6.18.54	b691a3e24427
2.6.22	7.2.8	7912ad8fb523
2.6.22	7.3	82e47533221d

Debian advisories