fkie_cve-2021-47439
Vulnerability from fkie_nvd
Published
2024-05-22 07:15
Modified
2025-04-02 15:14
Severity ?
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: net: dsa: microchip: Added the condition for scheduling ksz_mib_read_work When the ksz module is installed and removed using rmmod, kernel crashes with null pointer dereferrence error. During rmmod, ksz_switch_remove function tries to cancel the mib_read_workqueue using cancel_delayed_work_sync routine and unregister switch from dsa. During dsa_unregister_switch it calls ksz_mac_link_down, which in turn reschedules the workqueue since mib_interval is non-zero. Due to which queue executed after mib_interval and it tries to access dp->slave. But the slave is unregistered in the ksz_switch_remove function. Hence kernel crashes. To avoid this crash, before canceling the workqueue, resetted the mib_interval to 0. v1 -> v2: -Removed the if condition in ksz_mib_read_work
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378Patch
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3Patch
Impacted products
Vendor Product Version
linux linux_kernel *
linux linux_kernel *
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15
linux linux_kernel 5.15


To clipboard 

{
   configurations: [
      {
         nodes: [
            {
               cpeMatch: [
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                     matchCriteriaId: "FE277324-366F-4B37-A969-D1032D5FA58E",
                     versionEndExcluding: "5.10.75",
                     versionStartIncluding: "5.7",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                     matchCriteriaId: "BF43A331-D430-4B9D-A612-E63C62AE4A86",
                     versionEndExcluding: "5.14.14",
                     versionStartIncluding: "5.11",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*",
                     matchCriteriaId: "E46C74C6-B76B-4C94-A6A4-FD2FFF62D644",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*",
                     matchCriteriaId: "60134C3A-06E4-48C1-B04F-2903732A4E56",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*",
                     matchCriteriaId: "0460DA88-8FE1-46A2-9DDA-1F1ABA552E71",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:5.15:rc4:*:*:*:*:*:*",
                     matchCriteriaId: "AF55383D-4DF2-45DC-93F7-571F4F978EAB",
                     vulnerable: true,
                  },
                  {
                     criteria: "cpe:2.3:o:linux:linux_kernel:5.15:rc5:*:*:*:*:*:*",
                     matchCriteriaId: "9E9481B2-8AA6-4CBD-B5D3-C10F51FF6D01",
                     vulnerable: true,
                  },
               ],
               negate: false,
               operator: "OR",
            },
         ],
      },
   ],
   cveTags: [],
   descriptions: [
      {
         lang: "en",
         value: "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: dsa: microchip: Added the condition for scheduling ksz_mib_read_work\n\nWhen the ksz module is installed and removed using rmmod, kernel crashes\nwith null pointer dereferrence error. During rmmod, ksz_switch_remove\nfunction tries to cancel the mib_read_workqueue using\ncancel_delayed_work_sync routine and unregister switch from dsa.\n\nDuring dsa_unregister_switch it calls ksz_mac_link_down, which in turn\nreschedules the workqueue since mib_interval is non-zero.\nDue to which queue executed after mib_interval and it tries to access\ndp->slave. But the slave is unregistered in the ksz_switch_remove\nfunction. Hence kernel crashes.\n\nTo avoid this crash, before canceling the workqueue, resetted the\nmib_interval to 0.\n\nv1 -> v2:\n-Removed the if condition in ksz_mib_read_work",
      },
      {
         lang: "es",
         value: "En el kernel de Linux, se resolvió la siguiente vulnerabilidad: net: dsa: microchip: se agregó la condición para programar ksz_mib_read_work Cuando el módulo ksz se instala y elimina usando rmmod, el kernel falla con un error de desreferencia de puntero nulo. Durante rmmod, la función ksz_switch_remove intenta cancelar mib_read_workqueue usando la rutina cancel_delayed_work_sync y cancelar el registro del conmutador de dsa. Durante dsa_unregister_switch llama a ksz_mac_link_down, que a su vez reprograma la cola de trabajo ya que mib_interval no es cero. Debido a qué cola se ejecutó después de mib_interval e intenta acceder a dp->slave. Pero el esclavo no está registrado en la función ksz_switch_remove. Por lo tanto, el kernel falla. Para evitar este bloqueo, antes de cancelar la cola de trabajo, restableció mib_interval a 0. v1 -> v2: -Se eliminó la condición if en ksz_mib_read_work",
      },
   ],
   id: "CVE-2021-47439",
   lastModified: "2025-04-02T15:14:43.920",
   metrics: {
      cvssMetricV31: [
         {
            cvssData: {
               attackComplexity: "LOW",
               attackVector: "LOCAL",
               availabilityImpact: "HIGH",
               baseScore: 5.5,
               baseSeverity: "MEDIUM",
               confidentialityImpact: "NONE",
               integrityImpact: "NONE",
               privilegesRequired: "LOW",
               scope: "UNCHANGED",
               userInteraction: "NONE",
               vectorString: "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
               version: "3.1",
            },
            exploitabilityScore: 1.8,
            impactScore: 3.6,
            source: "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            type: "Secondary",
         },
      ],
   },
   published: "2024-05-22T07:15:09.163",
   references: [
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378",
      },
      {
         source: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3",
      },
      {
         source: "af854a3a-2127-422b-91ae-364da2661108",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/383239a33cf29ebee9ce0d4e0e5c900b77a16148",
      },
      {
         source: "af854a3a-2127-422b-91ae-364da2661108",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/ef1100ef20f29aec4e62abeccdb5bdbebba1e378",
      },
      {
         source: "af854a3a-2127-422b-91ae-364da2661108",
         tags: [
            "Patch",
         ],
         url: "https://git.kernel.org/stable/c/f2e1de075018cf71bcd7d628e9f759cb8540b0c3",
      },
   ],
   sourceIdentifier: "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
   vulnStatus: "Analyzed",
   weaknesses: [
      {
         description: [
            {
               lang: "en",
               value: "CWE-476",
            },
         ],
         source: "nvd@nist.gov",
         type: "Primary",
      },
   ],
}


Log in or create an account to share your comment.

Security Advisory comment format.

This schema specifies the format of a comment related to a security advisory.

UUIDv4 of the comment
UUIDv4 of the Vulnerability-Lookup instance
When the comment was created originally
When the comment was last updated
Title of the comment
Description of the comment
The identifier of the vulnerability (CVE ID, GHSA-ID, PYSEC ID, etc.).



Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.