Lucene search

LinuxCVE-2023-52909

HistoryAug 21, 2024 - 7:15 a.m.

CVE-2023-52909

2024-08-2107:15:06

CWE-476

Linux

web.nvd.nist.gov

linux

kernel

vulnerability

nfsd

fix

cached open files

CVSS3

4.7

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

NONE

Availability Impact

HIGH

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

AI Score

6.5

Confidence

High

EPSS

Percentile

5.1%

JSON

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

nfsd: fix handling of cached open files in nfsd4_open codepath

Commit fb70bf124b05 (“NFSD: Instantiate a struct file when creating a
regular NFSv4 file”) added the ability to cache an open fd over a
compound. There are a couple of problems with the way this currently
works:

It’s racy, as a newly-created nfsd_file can end up with its PENDING bit
cleared while the nf is hashed, and the nf_file pointer is still zeroed
out. Other tasks can find it in this state and they expect to see a
valid nf_file, and can oops if nf_file is NULL.

Also, there is no guarantee that we’ll end up creating a new nfsd_file
if one is already in the hash. If an extant entry is in the hash with a
valid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with
the value of op_file and the old nf_file will leak.

Fix both issues by making a new nfsd_file_acquirei_opened variant that
takes an optional file pointer. If one is present when this is called,
we’ll take a new reference to it instead of trying to open the file. If
the nfsd_file already has a valid nf_file, we’ll just ignore the
optional file and pass the nfsd_file back as-is.

Also rework the tracepoints a bit to allow for an “opened” variant and
don’t try to avoid counting acquisitions in the case where we already
have a cached open file.

Affected configurations

Nvd

Vulners

Node

linuxlinux_kernelRange5.19–6.1.7

linuxlinux_kernelMatch6.2rc1

linuxlinux_kernelMatch6.2rc2

linuxlinux_kernelMatch6.2rc3

VendorProductVersionCPE
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel6.2cpe:2.3:o:linux:linux_kernel:6.2:rc1:*:*:*:*:*:*
linuxlinux_kernel6.2cpe:2.3:o:linux:linux_kernel:6.2:rc2:*:*:*:*:*:*
linuxlinux_kernel6.2cpe:2.3:o:linux:linux_kernel:6.2:rc3:*:*:*:*:*:*

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.2	cpe:2.3:o:linux:linux_kernel:6.2:rc1::::::
linux	linux_kernel	6.2	cpe:2.3:o:linux:linux_kernel:6.2:rc2::::::
linux	linux_kernel	6.2	cpe:2.3:o:linux:linux_kernel:6.2:rc3::::::

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "fs/nfsd/filecache.c",
      "fs/nfsd/filecache.h",
      "fs/nfsd/nfs4state.c",
      "fs/nfsd/trace.h"
    ],
    "versions": [
      {
        "version": "c20097329d2c",
        "lessThan": "45c08a752982",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "106331a12b0f",
        "lessThan": "0b778361998d",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fb70bf124b05",
        "lessThan": "973acfdfe90c",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fb70bf124b05",
        "lessThan": "0b3a551fa58b",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "fs/nfsd/filecache.c",
      "fs/nfsd/filecache.h",
      "fs/nfsd/nfs4state.c",
      "fs/nfsd/trace.h"
    ],
    "versions": [
      {
        "version": "5.19",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.19",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.7",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.2",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]