CVE-2024-26704

2024-04-0315:15:53

416baaa9-dc9f-4396-8d5f-8c081fb06d67

web.nvd.nist.gov

linux kernel

ext4

vulnerability fix

double-free vulnerability

update move_len

6 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

12.9%

JSON

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

ext4: fix double-free of blocks due to wrong extents moved_len

In ext4_move_extents(), moved_len is only updated when all moves are
successfully executed, and only discards orig_inode and donor_inode
preallocations when moved_len is not zero. When the loop fails to exit
after successfully moving some extents, moved_len is not updated and
remains at 0, so it does not discard the preallocations.

If the moved extents overlap with the preallocated extents, the
overlapped extents are freed twice in ext4_mb_release_inode_pa() and
ext4_process_freed_data() (as described in commit 94d7c16cbbbd (“ext4:
Fix double-free of blocks with EXT4_IOC_MOVE_EXT”)), and bb_free is
incremented twice. Hence when trim is executed, a zero-division bug is
triggered in mb_update_avg_fragment_size() because bb_free is not zero
and bb_fragments is zero.

Therefore, update move_len after each extent move to avoid the issue.

Affected configurations

Vulners

Node

linuxlinux_kernelRange3.18–4.19.307

linuxlinux_kernelRange4.20.0–5.4.269

linuxlinux_kernelRange5.5.0–5.10.210

linuxlinux_kernelRange5.11.0–5.15.149

linuxlinux_kernelRange5.16.0–6.1.79

linuxlinux_kernelRange6.2.0–6.6.18

linuxlinux_kernelRange6.7.0–6.7.6

linuxlinux_kernelRange6.8.0≥

VendorProductVersionCPE
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linuxlinux_kernel*cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

Vendor	Product	Version	CPE
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	*	cpe:2.3:o:linux:linux_kernel::::::::

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "fs/ext4/move_extent.c"
    ],
    "versions": [
      {
        "version": "fcf6b1b729bc",
        "lessThan": "b4fbb89d722c",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "afbcad9ae7d6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "d033a555d9a1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "afba9d11320d",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "185eab30486b",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "2883940b19c3",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "559ddacb90da",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "fcf6b1b729bc",
        "lessThan": "55583e899a53",
        "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/ext4/move_extent.c"
    ],
    "versions": [
      {
        "version": "3.18",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "3.18",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "4.19.307",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.269",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.210",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.149",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.79",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.18",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.6",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]