CVE-2021-47179 NFSv4: Fix a NULL pointer dereference in pnfs_mark_matching_lsegs_return()

2024-03-2509:16:28

Linux

github.com

linux kernel

nfsv4

null pointer dereference

pnfs_mark_matching_lsegs_return

pnfs_layout_range

oops

connectathon basic tests

nfs v4.1

nfs v4.2

ontap

AI Score

6.7

Confidence

Low

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

NFSv4: Fix a NULL pointer dereference in pnfs_mark_matching_lsegs_return()

Commit de144ff4234f changes _pnfs_return_layout() to call
pnfs_mark_matching_lsegs_return() passing NULL as the struct
pnfs_layout_range argument. Unfortunately,
pnfs_mark_matching_lsegs_return() doesn’t check if we have a value here
before dereferencing it, causing an oops.

I’m able to hit this crash consistently when running connectathon basic
tests on NFS v4.1/v4.2 against Ontap.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "80e34f4957ec",
        "lessThan": "4e1ba532dbc1",
        "versionType": "git"
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        "status": "affected",
        "version": "7b7b97746432",
        "lessThan": "42637ca25c7d",
        "versionType": "git"
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        "status": "affected",
        "version": "9ffa7967f937",
        "lessThan": "39785761fead",
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      {
        "status": "affected",
        "version": "6be0e4b59314",
        "lessThan": "aba3c7795f51",
        "versionType": "git"
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      {
        "status": "affected",
        "version": "2fafe7d5047f",
        "lessThan": "f9890652185b",
        "versionType": "git"
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        "status": "affected",
        "version": "7e65ea887d0c",
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        "status": "affected",
        "version": "de144ff4234f",
        "lessThan": "a421d218603f",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "fs/nfs/pnfs.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "4.9.269",
        "lessThan": "4.9.271",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "4.14.233",
        "lessThan": "4.14.235",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "4.19.191",
        "lessThan": "4.19.193",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "5.4.118",
        "lessThan": "5.4.124",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "5.10.36",
        "lessThan": "5.10.42",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "5.12.3",
        "lessThan": "5.12.9",
        "versionType": "custom"
      }
    ],
    "programFiles": [
      "fs/nfs/pnfs.c"
    ],
    "defaultStatus": "unaffected"
  }
]