ghsa-fxvq-h88x-3jfr
Vulnerability from github
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": [],
"aliases": [
"CVE-2024-46744"
],
"database_specific": {
"cwe_ids": [
"CWE-59"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-09-18T08:15:03Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nSquashfs: sanity check symbolic link size\n\nSyzkiller reports a \"KMSAN: uninit-value in pick_link\" bug.\n\nThis is caused by an uninitialised page, which is ultimately caused\nby a corrupted symbolic link size read from disk.\n\nThe reason why the corrupted symlink size causes an uninitialised\npage is due to the following sequence of events:\n\n1. squashfs_read_inode() is called to read the symbolic\n link from disk. This assigns the corrupted value\n 3875536935 to inode-\u003ei_size.\n\n2. Later squashfs_symlink_read_folio() is called, which assigns\n this corrupted value to the length variable, which being a\n signed int, overflows producing a negative number.\n\n3. The following loop that fills in the page contents checks that\n the copied bytes is less than length, which being negative means\n the loop is skipped, producing an uninitialised page.\n\nThis patch adds a sanity check which checks that the symbolic\nlink size is not larger than expected.\n\n--\n\nV2: fix spelling mistake.",
"id": "GHSA-fxvq-h88x-3jfr",
"modified": "2024-09-30T15:30:44Z",
"published": "2024-09-18T09:30:36Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-46744"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/087f25b2d36adae19951114ffcbb7106ed405ebb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1b9451ba6f21478a75288ea3e3fca4be35e2a438"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5c8906de98d0d7ad42ff3edf2cb6cd7e0ea658c4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/810ee43d9cd245d138a2733d87a24858a23f577d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c3af7e460a526007e4bed1ce3623274a1a6afe5e"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ef4e249971eb77ec33d74c5c3de1e2576faf6c90"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f82cb7f24032ed023fc67d26ea9bf322d8431a90"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fac5e82ab1334fc8ed6ff7183702df634bd1d93d"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.