CVE-2026-80917

CVE Details

Release Date:	2026-09-09
Impact:	Low	What is this?

Description

In the Linux kernel, the following vulnerability has been resolved: PCI: host-generic: Fix NULL pointer dereference on 32-bit CAM systems On 32-bit systems the config space is too large to ioremap in one go, so pci_ecam_create() maps each bus segment separately and relies on the ->add_bus callback (pci_ecam_add_bus) to populate the per-bus mapping in cfg->winp[]. pci_ecam_map_bus() then uses that mapping as the base for every config access. The generic ECAM ops (pci_generic_ecam_ops) already provide the ->add_bus and ->remove_bus callbacks, but the CAM (legacy) ops in pci-host-generic.c do not. As a result, on a 32-bit host using "pci-host-cam-generic" the per-bus mapping is never set up and the first config read dereferences a NULL base, crashing during bus enumeration: Unable to handle kernel NULL pointer dereference at virtual address 00000800 Oops [#1] CPU: 0 PID: 1 Comm: swapper Not tainted 6.9.7+ #43 Hardware name: Digilent Nexys-Video-A7 RV32 (DT) epc : pci_generic_config_read+0x40/0xb0 ra : pci_generic_config_read+0x2c/0xb0 [] pci_generic_config_read+0x40/0xb0 [] pci_bus_read_config_dword+0x50/0xb0 [] pci_bus_generic_read_dev_vendor_id+0x3c/0x1ec [] pci_scan_single_device+0xa4/0x11c [] pci_scan_slot+0x9c/0x23c [] pci_scan_child_bus_extend+0x58/0x2f4 [] pci_scan_root_bus_bridge+0x64/0xe8 [] pci_host_probe+0x20/0xc8 [] pci_host_common_probe+0x144/0x1e4 Fix this by giving the CAM ops the same ->add_bus/->remove_bus callbacks. Since pci_ecam_add_bus() and pci_ecam_remove_bus() are static to ecam.c, move the CAM ops definition there as pci_generic_cam_ops (mirroring pci_generic_ecam_ops) and export it for pci-host-generic.c to reference. [mani: removed timestamp from log]

See more information about CVE-2026-80917 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	4.1
Vector String:	CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	High
Privileges Required:	High
User Interaction:	None
Scope:	Unchanged
Confidentiality Impact:	None
Integrity Impact:	None
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 8 (kernel-uek)	ELSA-2026-500377	2026-10-07
Oracle Linux version 9 (kernel-uek)	ELSA-2026-500374	2026-10-07
Oracle Linux version 9 (kernel-uek)	ELSA-2026-500377	2026-10-07