CVE-2024-46744

2024-09-1808:15:03

Linux

web.nvd.nist.gov

linux kernel

squashfs

symbolic link

vulnerability

kmsan

inode size

symlink size

uninit-value

patch

sanity check

AI Score

6.3

Confidence

Low

EPSS

Percentile

13.8%

JSON

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

Squashfs: sanity check symbolic link size

Syzkiller reports a “KMSAN: uninit-value in pick_link” bug.

This is caused by an uninitialised page, which is ultimately caused
by a corrupted symbolic link size read from disk.

The reason why the corrupted symlink size causes an uninitialised
page is due to the following sequence of events:

squashfs_read_inode() is called to read the symbolic
link from disk. This assigns the corrupted value
3875536935 to inode->i_size.
Later squashfs_symlink_read_folio() is called, which assigns
this corrupted value to the length variable, which being a
signed int, overflows producing a negative number.
The following loop that fills in the page contents checks that
the copied bytes is less than length, which being negative means
the loop is skipped, producing an uninitialised page.

This patch adds a sanity check which checks that the symbolic
link size is not larger than expected.

–

V2: fix spelling mistake.

Affected configurations

Vulners

Node

linuxlinux_kernelRange4.19.0–4.19.322

linuxlinux_kernelRange4.20.0–5.4.284

linuxlinux_kernelRange5.5.0–5.10.226

linuxlinux_kernelRange5.11.0–5.15.167

linuxlinux_kernelRange5.16.0–6.1.110

linuxlinux_kernelRange6.2.0–6.6.51

linuxlinux_kernelRange6.7.0–6.10.10

linuxlinux_kernelRange6.11.0≥

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

Vendor	Product	Version	CPE
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/squashfs/inode.c"
    ],
    "versions": [
      {
        "version": "1da177e4c3f4",
        "lessThan": "f82cb7f24032",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "1b9451ba6f21",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "5c8906de98d0",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "087f25b2d36a",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "fac5e82ab133",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "c3af7e460a52",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "ef4e249971eb",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "1da177e4c3f4",
        "lessThan": "810ee43d9cd2",
        "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/squashfs/inode.c"
    ],
    "versions": [
      {
        "version": "4.19.322",
        "lessThanOrEqual": "4.19.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.4.284",
        "lessThanOrEqual": "5.4.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.226",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.167",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.110",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.51",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.10.10",
        "lessThanOrEqual": "6.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.11",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]