CVE-2026-98878

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: irqchip/gic-v5: Immediately exec priority drop following activate With GICv5 an interrupt of equal or lower priority cannot be signalled until there has been a priority drop. This is done via the GIC CDEOI system instruction. Once this has been executed, the hardware is able to signal the next interrupt if there is one. As all interrupts are programmed to have the same priority, no new interrupts can be signalled until the priority drop has happened. This can cause issues when, for example, an interrupt remains active while a long running process takes place, such as when injecting a physical interrupt into a guest VM in software. The GICv5 driver has so far done the priority drop as part of irq_eoi(), i.e., at the same time as deactivating the interrupt. This means that any long running process (or VM) could block incoming interrupts, effectively causing a denial of service for all other interrupts. Rather than doing the EOI as part of irq_eoi() (which the name would suggest would be a good place for it), move it to happen immediately after acknowledging an interrupt in the main GICv5 interrupt handler. The deactivation of interrupts (GIC CDDI) remains implemented as part of irq_eoi(), which means that the same interrupt cannot be signalled a second time until deactivated by software.

Severity

Not scored

CVSS score

Not available

Vulnerability status

Received

Source identifier

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Published

2026-10-23 12:18:21.330000

Last modified

2026-10-26 07:17:12.297000

View original CVE JSON

{
  "id": "CVE-2026-98878",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-10-23T12:18:21.330",
  "lastModified": "2026-10-26T07:17:12.297",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nirqchip/gic-v5: Immediately exec priority drop following activate\n\nWith GICv5 an interrupt of equal or lower priority cannot be signalled\nuntil there has been a priority drop. This is done via the GIC CDEOI\nsystem instruction. Once this has been executed, the hardware is able\nto signal the next interrupt if there is one.\n\nAs all interrupts are programmed to have the same priority, no new\ninterrupts can be signalled until the priority drop has happened. This\ncan cause issues when, for example, an interrupt remains active while\na long running process takes place, such as when injecting a physical\ninterrupt into a guest VM in software.\n\nThe GICv5 driver has so far done the priority drop as part of\nirq_eoi(), i.e., at the same time as deactivating the interrupt. This\nmeans that any long running process (or VM) could block incoming\ninterrupts, effectively causing a denial of service for all other\ninterrupts.\n\nRather than doing the EOI as part of irq_eoi() (which the name would\nsuggest would be a good place for it), move it to happen immediately\nafter acknowledging an interrupt in the main GICv5 interrupt\nhandler. The deactivation of interrupts (GIC CDDI) remains implemented\nas part of irq_eoi(), which means that the same interrupt cannot be\nsignalled a second time until deactivated by software."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/irqchip/irq-gic-v5.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "7ec80fb3f025825e860b433685fb801d6de34bf3",
              "lessThan": "c29bb5acd0cad0b49399d1399dd1bacb39e41438",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "7ec80fb3f025825e860b433685fb801d6de34bf3",
              "lessThan": "abf60331ebe9a9a7937a72aac7699c2907ab9307",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/irqchip/irq-gic-v5.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.53",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {},
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/abf60331ebe9a9a7937a72aac7699c2907ab9307",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/c29bb5acd0cad0b49399d1399dd1bacb39e41438",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}