CVE-2022-49810

Estado: AnalizadaMedia (5.5)—

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

netfs: Fix missing xas_retry() calls in xarray iteration

netfslib has a number of places in which it performs iteration of an xarray whilst being under the RCU read lock. It *should* call xas_retry() as the first thing inside of the loop and do "continue" if it returns true in case the xarray walker passed out a special value indicating that the walk needs to be redone from the root[*].

Fix this by adding the missing retry checks.

This can cause an oops like that below. Note the faulting address - this is an internal value (|0x2) returned from xarray.

Leer descripción completaMostrar menos

Changes: ======== ver #2) - Changed an unsigned int to a size_t to reduce the likelihood of an overflow as per Willy's suggestion. - Added an additional patch to fix the maths.

Detalles técnicos trazas, registros y código del informe original

[*] I wonder if this should be done inside xas_find(), xas_next_node() and
    suchlike, but I'm told that's not an simple change to effect.

BUG: kernel NULL pointer dereference, address: 0000000000000402
...
RIP: 0010:netfs_rreq_unlock+0xef/0x380 [netfs]
...
Call Trace:
 netfs_rreq_assess+0xa6/0x240 [netfs]
 netfs_readpage+0x173/0x3b0 [netfs]
 ? init_wait_var_entry+0x50/0x50
 filemap_read_page+0x33/0xf0
 filemap_get_pages+0x2f2/0x3f0
 filemap_read+0xaa/0x320
 ? do_filp_open+0xb2/0x150
 ? rmqueue+0x3be/0xe10
 ceph_read_iter+0x1fe/0x680 [ceph]
 ? new_sync_read+0x115/0x1a0
 new_sync_read+0x115/0x1a0
 vfs_read+0xf3/0x180
 ksys_read+0x5f/0xe0
 do_syscall_64+0x38/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 5.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.17%
Percentil entre todas las CVEs puntuadas: 6
Fecha de la puntuación: 5/10/2026

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-476

Referencias

JSON original (NVD)

Mostrar

{
  "id": "CVE-2022-49810",
  "cveTags": [],
  "metrics": {
    "cvssMetricV31": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 5.5,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 3.6,
        "exploitabilityScore": 1.8
      }
    ]
  },
  "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": "3d3c95046742e4eebaa4b891b0b01cbbed94ebbd",
              "lessThan": "b2cc07a76f1eb12de3b22caf5fdbf856a7bef16d",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3d3c95046742e4eebaa4b891b0b01cbbed94ebbd",
              "lessThan": "7e043a80b5dae5c2d2cf84031501de7827fd6c00",
              "versionType": "git"
            }
          ],
          "programFiles": [
            "fs/netfs/buffered_read.c",
            "fs/netfs/io.c"
          ],
          "defaultStatus": "unaffected"
        },
        {
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "product": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "5.13"
            },
            {
              "status": "unaffected",
              "version": "0",
              "lessThan": "5.13",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.0.10",
              "versionType": "semver",
              "lessThanOrEqual": "6.0.*"
            },
            {
              "status": "unaffected",
              "version": "6.1",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ],
          "programFiles": [
            "fs/netfs/buffered_read.c",
            "fs/netfs/io.c"
          ],
          "defaultStatus": "affected"
        }
      ]
    }
  ],
  "published": "2025-05-01T15:16:04.347",
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/7e043a80b5dae5c2d2cf84031501de7827fd6c00",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b2cc07a76f1eb12de3b22caf5fdbf856a7bef16d",
      "tags": [
        "Patch"
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-476"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix missing xas_retry() calls in xarray iteration\n\nnetfslib has a number of places in which it performs iteration of an xarray\nwhilst being under the RCU read lock.  It *should* call xas_retry() as the\nfirst thing inside of the loop and do \"continue\" if it returns true in case\nthe xarray walker passed out a special value indicating that the walk needs\nto be redone from the root[*].\n\nFix this by adding the missing retry checks.\n\n[*] I wonder if this should be done inside xas_find(), xas_next_node() and\n    suchlike, but I'm told that's not an simple change to effect.\n\nThis can cause an oops like that below.  Note the faulting address - this\nis an internal value (|0x2) returned from xarray.\n\nBUG: kernel NULL pointer dereference, address: 0000000000000402\n...\nRIP: 0010:netfs_rreq_unlock+0xef/0x380 [netfs]\n...\nCall Trace:\n netfs_rreq_assess+0xa6/0x240 [netfs]\n netfs_readpage+0x173/0x3b0 [netfs]\n ? init_wait_var_entry+0x50/0x50\n filemap_read_page+0x33/0xf0\n filemap_get_pages+0x2f2/0x3f0\n filemap_read+0xaa/0x320\n ? do_filp_open+0xb2/0x150\n ? rmqueue+0x3be/0xe10\n ceph_read_iter+0x1fe/0x680 [ceph]\n ? new_sync_read+0x115/0x1a0\n new_sync_read+0x115/0x1a0\n vfs_read+0xf3/0x180\n ksys_read+0x5f/0xe0\n do_syscall_64+0x38/0x90\n entry_SYSCALL_64_after_hwframe+0x44/0xae\n\nChanges:\n========\nver #2)\n - Changed an unsigned int to a size_t to reduce the likelihood of an\n   overflow as per Willy's suggestion.\n - Added an additional patch to fix the maths."
    },
    {
      "lang": "es",
      "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfs: Se corrigen las llamadas xas_retry() faltantes en la iteración de un xarray. netfslib realiza la iteración de un xarray en varios lugares bajo el bloqueo de lectura de la RCU. *Debería* llamar a xas_retry() como primer paso dentro del bucle y ejecutar \"continue\" si devuelve verdadero en caso de que el rastreador de xarrays haya pasado un valor especial que indique que el recorrido debe rehacerse desde la raíz. [*] Se puede solucionar añadiendo las comprobaciones de reintento faltantes. [*] Me pregunto si esto debería hacerse dentro de xas_find(), xas_next_node() y similares, pero me han dicho que no es un cambio sencillo de implementar. Esto puede causar un error como el que se muestra a continuación. Observe la dirección del error: se trata de un valor interno (|0x2) devuelto por xarray. ERROR: desreferencia de puntero NULL del núcleo, dirección: 0000000000000402 ... RIP: 0010:netfs_rreq_unlock+0xef/0x380 [netfs] ... Seguimiento de llamadas: netfs_rreq_assess+0xa6/0x240 [netfs] netfs_readpage+0x173/0x3b0 [netfs] ? init_wait_var_entry+0x50/0x50 filemap_read_page+0x33/0xf0 filemap_get_pages+0x2f2/0x3f0 filemap_read+0xaa/0x320 ? do_filp_open+0xb2/0x150 ? rmqueue+0x3be/0xe10 ceph_read_iter+0x1fe/0x680 [ceph] ? new_sync_read+0x115/0x1a0 new_sync_read+0x115/0x1a0 vfs_read+0xf3/0x180 ksys_read+0x5f/0xe0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Changes: ======== ver #2) - Se cambió un int sin signo a un size_t para reducir la probabilidad de un desbordamiento según la sugerencia de Willy. - Se agregó un parche adicional para corregir las matemáticas."
    }
  ],
  "lastModified": "2026-06-17T05:19:12.043",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "2FF408D3-ACA7-41DC-8339-17AAAF160282",
              "versionEndExcluding": "6.0.10",
              "versionStartIncluding": "5.13"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.1:rc1:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E7E331DA-1FB0-4DEC-91AC-7DA69D461C11"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.1:rc2:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "17F0B248-42CF-4AE6-A469-BB1BAE7F4705"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.1:rc3:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "E2422816-0C14-4B5E-A1E6-A9D776E5C49B"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.1:rc4:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "1C6E00FE-5FB9-4D20-A1A1-5A32128F9B76"
            },
            {
              "criteria": "cpe:2.3:o:linux:linux_kernel:6.1:rc5:*:*:*:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "35B26BE4-43A6-4A36-A7F6-5B3F572D9186"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}