CVE-2026-43313

Summary

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

ACPI: processor: Fix NULL-pointer dereference in acpi_processor_errata_piix4()

In acpi_processor_errata_piix4(), the pointer dev is first assigned an IDE device and then reassigned an ISA device:

dev = pci_get_subsys(…, PCI_DEVICE_ID_INTEL_82371AB, …); dev = pci_get_subsys(…, PCI_DEVICE_ID_INTEL_82371AB_0, …);

If the first lookup succeeds but the second fails, dev becomes NULL. This leads to a potential null-pointer dereference when dev_dbg() is called:

if (errata.piix4.bmisx) dev_dbg(&dev->dev, …);

To prevent this, use two temporary pointers and retrieve each device independently, avoiding overwriting dev with a possible NULL value.

[ rjw: Subject adjustment, added an empty code line ]

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 06724a60cfa9767ea90b0f5d3dfb5cdd251b64f5affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < ad86ac604f8391c0212a91412d4f764c7a85f254affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 01e8751b37a366b1ca561add0042f2ceb18c03bfaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < b803811485ac0b2f774b6bf3abc8b999ba3b7033affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 29f60d3d06818d40118a30d663231f027ae87a05affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 0398b641be2b66c2fc7e0163c606ef19372e7ad5affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f132e089fe89cadc2098991f0a3cb05c3f824ac6affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux5.15.202 <= 5.15.*unaffected
LinuxLinux6.1.165 <= 6.1.*unaffected
LinuxLinux6.6.128 <= 6.6.*unaffected
LinuxLinux6.12.75 <= 6.12.*unaffected
LinuxLinux6.18.16 <= 6.18.*unaffected
LinuxLinux6.19.6 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References