FKIE_CVE-2025-68209

Vulnerability from fkie_nvd - Published: 2025-12-16 14:15 - Updated: 2026-10-30 13:18
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: mlx5: Fix default values in create CQ Currently, CQs without a completion function are assigned the mlx5_add_cq_to_tasklet function by default. This is problematic since only user CQs created through the mlx5_ib driver are intended to use this function. Additionally, all CQs that will use doorbells instead of polling for completions must call mlx5_cq_arm. However, the default CQ creation flow leaves a valid value in the CQ's arm_db field, allowing FW to send interrupts to polling-only CQs in certain corner cases. These two factors would allow a polling-only kernel CQ to be triggered by an EQ interrupt and call a completion function intended only for user CQs, causing a null pointer exception. Some areas in the driver have prevented this issue with one-off fixes but did not address the root cause. This patch fixes the described issue by adding defaults to the create CQ flow. It adds a default dummy completion function to protect against null pointer exceptions, and it sets an invalid command sequence number by default in kernel CQs to prevent the FW from sending an interrupt to the CQ until it is armed. User CQs are responsible for their own initialization values. Callers of mlx5_core_create_cq are responsible for changing the completion function and arming the CQ per their needs.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/08469f5393a1a39f26a6e2eb2e8c33187665c1f4
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1a7865e3e4de2830d8a9fe8c273dc10b248b7338
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/5c08079c3e5a3c1573afcb5643b5d296865d1170
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/a39d334c9840705af69f0466f8f0129c366004ca
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/e5eba42f01340f73888dfe560be2806057c25913
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/infiniband/hw/mlx5/cq.c",
            "drivers/net/ethernet/mellanox/mlx5/core/cq.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_main.c",
            "drivers/net/ethernet/mellanox/mlx5/core/fpga/conn.c",
            "drivers/net/ethernet/mellanox/mlx5/core/steering/hws/send.c",
            "drivers/net/ethernet/mellanox/mlx5/core/steering/sws/dr_send.c",
            "drivers/vdpa/mlx5/net/mlx5_vnet.c",
            "include/linux/mlx5/cq.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5c08079c3e5a3c1573afcb5643b5d296865d1170",
              "status": "affected",
              "version": "cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa",
              "versionType": "git"
            },
            {
              "lessThan": "1a7865e3e4de2830d8a9fe8c273dc10b248b7338",
              "status": "affected",
              "version": "cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa",
              "versionType": "git"
            },
            {
              "lessThan": "a39d334c9840705af69f0466f8f0129c366004ca",
              "status": "affected",
              "version": "cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa",
              "versionType": "git"
            },
            {
              "lessThan": "08469f5393a1a39f26a6e2eb2e8c33187665c1f4",
              "status": "affected",
              "version": "cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa",
              "versionType": "git"
            },
            {
              "lessThan": "e5eba42f01340f73888dfe560be2806057c25913",
              "status": "affected",
              "version": "cdd04f4d4d71cbf93d0d9abe63bc838f47c467fa",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "drivers/infiniband/hw/mlx5/cq.c",
            "drivers/net/ethernet/mellanox/mlx5/core/cq.c",
            "drivers/net/ethernet/mellanox/mlx5/core/en_main.c",
            "drivers/net/ethernet/mellanox/mlx5/core/fpga/conn.c",
            "drivers/net/ethernet/mellanox/mlx5/core/steering/hws/send.c",
            "drivers/net/ethernet/mellanox/mlx5/core/steering/sws/dr_send.c",
            "drivers/vdpa/mlx5/net/mlx5_vnet.c",
            "include/linux/mlx5/cq.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.0"
            },
            {
              "lessThan": "6.0",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.1.*",
              "status": "unaffected",
              "version": "6.1.191",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.160",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.114",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.17.*",
              "status": "unaffected",
              "version": "6.17.9",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.18",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmlx5: Fix default values in create CQ\n\nCurrently, CQs without a completion function are assigned the\nmlx5_add_cq_to_tasklet function by default. This is problematic since\nonly user CQs created through the mlx5_ib driver are intended to use\nthis function.\n\nAdditionally, all CQs that will use doorbells instead of polling for\ncompletions must call mlx5_cq_arm. However, the default CQ creation flow\nleaves a valid value in the CQ\u0027s arm_db field, allowing FW to send\ninterrupts to polling-only CQs in certain corner cases.\n\nThese two factors would allow a polling-only kernel CQ to be triggered\nby an EQ interrupt and call a completion function intended only for user\nCQs, causing a null pointer exception.\n\nSome areas in the driver have prevented this issue with one-off fixes\nbut did not address the root cause.\n\nThis patch fixes the described issue by adding defaults to the create CQ\nflow. It adds a default dummy completion function to protect against\nnull pointer exceptions, and it sets an invalid command sequence number\nby default in kernel CQs to prevent the FW from sending an interrupt to\nthe CQ until it is armed. User CQs are responsible for their own\ninitialization values.\n\nCallers of mlx5_core_create_cq are responsible for changing the\ncompletion function and arming the CQ per their needs."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmlx5: Corrige valores predeterminados en la creaci\u00f3n de CQ\n\nActualmente, a las CQ sin una funci\u00f3n de completado se les asigna la funci\u00f3n mlx5_add_cq_to_tasklet por defecto. Esto es problem\u00e1tico ya que solo las CQ de usuario creadas a trav\u00e9s del controlador mlx5_ib est\u00e1n destinadas a usar esta funci\u00f3n.\n\nAdem\u00e1s, todas las CQ que usar\u00e1n \u0027doorbells\u0027 en lugar de sondeo para completados deben llamar a mlx5_cq_arm. Sin embargo, el flujo de creaci\u00f3n de CQ por defecto deja un valor v\u00e1lido en el campo arm_db de la CQ, permitiendo que el FW env\u00ede interrupciones a las CQ solo de sondeo en ciertos casos extremos.\n\nEstos dos factores permitir\u00edan que una CQ de kernel solo de sondeo fuera activada por una interrupci\u00f3n EQ y llamara a una funci\u00f3n de completado destinada solo a CQ de usuario, causando una excepci\u00f3n de puntero nulo.\n\nAlgunas \u00e1reas en el controlador han prevenido este problema con correcciones puntuales, pero no abordaron la causa ra\u00edz.\n\nEste parche corrige el problema descrito a\u00f1adiendo valores predeterminados al flujo de creaci\u00f3n de CQ. A\u00f1ade una funci\u00f3n de completado ficticia predeterminada para proteger contra excepciones de puntero nulo, y establece un n\u00famero de secuencia de comando inv\u00e1lido por defecto en las CQ del kernel para evitar que el FW env\u00ede una interrupci\u00f3n a la CQ hasta que est\u00e9 armada. Las CQ de usuario son responsables de sus propios valores de inicializaci\u00f3n.\n\nLos que llaman a mlx5_core_create_cq son responsables de cambiar la funci\u00f3n de completado y armar la CQ seg\u00fan sus necesidades."
    }
  ],
  "id": "CVE-2025-68209",
  "lastModified": "2026-10-30T13:18:18.147",
  "metrics": {},
  "published": "2025-12-16T14:15:53.813",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/08469f5393a1a39f26a6e2eb2e8c33187665c1f4"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1a7865e3e4de2830d8a9fe8c273dc10b248b7338"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/5c08079c3e5a3c1573afcb5643b5d296865d1170"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/a39d334c9840705af69f0466f8f0129c366004ca"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e5eba42f01340f73888dfe560be2806057c25913"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Deferred"
}



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