CVE-2026-90315

In the Linux kernel, the following vulnerability has been resolved: PCI/sysfs: Add lockdown checks to legacy I/O and memory handlers Currently, the legacy I/O and memory sysfs handlers do not check security_locked_down(LOCKDOWN_PCI_ACCESS), leaving the legacy_io and legacy_mem files unprotected when the kernel is locked down. Commit eb627e17727e ("PCI: Lock down BAR access when the kernel is locked down") added the check to pci_write_config(), pci_mmap_resource(), and pci_write_resource_io() to prevent userspace from programming DMA-capable hardware that could be used to modify kernel code, but did not cover the legacy handlers. As a result, root can still write arbitrary I/O ports and map the legacy I/O and memory spaces while the kernel is locked down, which is the same capability the lockdown is meant to remove. Add the same check to pci_write_legacy_io(), pci_mmap_legacy_mem(), and pci_mmap_legacy_io(). These generic handlers cover both architectures that define HAVE_PCI_LEGACY (such as Alpha and PowerPC). [bhelgaas: add Link]

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/747b9bbbbdfdee51aee2456388f9b94b5086de4d
https://git.kernel.org/stable/c/cd07aef510ac6a2873e01f9ddddc5492490b0067

Configurations

No configuration.

History

17 Sep 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 17:17

Updated : 2026-09-17 17:17

NVD link : CVE-2026-90315

Mitre link : CVE-2026-90315

CVE.ORG link : CVE-2026-90315

JSON object : View

Products Affected

No product.

CWE

No CWE.

{"id": "CVE-2026-90315", "cveTags": [], "metrics": {}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "eb627e17727ebeede70697ae1798688b0d328b54", "lessThan": "cd07aef510ac6a2873e01f9ddddc5492490b0067", "versionType": "git"}, {"status": "affected", "version": "eb627e17727ebeede70697ae1798688b0d328b54", "lessThan": "747b9bbbbdfdee51aee2456388f9b94b5086de4d", "versionType": "git"}], "programFiles": ["drivers/pci/pci-sysfs.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.4"}, {"status": "unaffected", "version": "0", "lessThan": "5.4", "versionType": "semver"}, {"status": "unaffected", "version": "7.2.6", "versionType": "semver", "lessThanOrEqual": "7.2.*"}, {"status": "unaffected", "version": "7.3-rc1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["drivers/pci/pci-sysfs.c"], "defaultStatus": "affected"}]}], "published": "2026-09-17T17:17:29.340", "references": [{"url": "https://git.kernel.org/stable/c/747b9bbbbdfdee51aee2456388f9b94b5086de4d", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cd07aef510ac6a2873e01f9ddddc5492490b0067", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Received", "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI/sysfs: Add lockdown checks to legacy I/O and memory handlers\n\nCurrently, the legacy I/O and memory sysfs handlers do not check\nsecurity_locked_down(LOCKDOWN_PCI_ACCESS), leaving the legacy_io and\nlegacy_mem files unprotected when the kernel is locked down.\n\nCommit eb627e17727e (\"PCI: Lock down BAR access when the kernel is locked\ndown\") added the check to pci_write_config(), pci_mmap_resource(), and\npci_write_resource_io() to prevent userspace from programming DMA-capable\nhardware that could be used to modify kernel code, but did not cover the\nlegacy handlers.\n\nAs a result, root can still write arbitrary I/O ports and map the legacy\nI/O and memory spaces while the kernel is locked down, which is the same\ncapability the lockdown is meant to remove.\n\nAdd the same check to pci_write_legacy_io(), pci_mmap_legacy_mem(), and\npci_mmap_legacy_io().\n\nThese generic handlers cover both architectures that define HAVE_PCI_LEGACY\n(such as Alpha and PowerPC).\n\n[bhelgaas: add Link]"}], "lastModified": "2026-09-17T17:17:29.340", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}