ghsa-9xp8-8c5r-6wfh
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
ceph: prevent use-after-free in encode_cap_msg()
In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This implies before the refcount could be increment here, it was freed.
In same file, in "handle_cap_grant()" refcount is decremented by this line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race occurred and resource was freed by the latter line before the former line could increment it.
encode_cap_msg() is called by __send_cap() and __send_cap() is called by ceph_check_caps() after calling __prep_cap(). __prep_cap() is where arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where the refcount must be increased to prevent "use after free" error.
{
"affected": [],
"aliases": [
"CVE-2024-26689"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-03T15:15:52Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: prevent use-after-free in encode_cap_msg()\n\nIn fs/ceph/caps.c, in encode_cap_msg(), \"use after free\" error was\ncaught by KASAN at this line - \u0027ceph_buffer_get(arg-\u003exattr_buf);\u0027. This\nimplies before the refcount could be increment here, it was freed.\n\nIn same file, in \"handle_cap_grant()\" refcount is decremented by this\nline - \u0027ceph_buffer_put(ci-\u003ei_xattrs.blob);\u0027. It appears that a race\noccurred and resource was freed by the latter line before the former\nline could increment it.\n\nencode_cap_msg() is called by __send_cap() and __send_cap() is called by\nceph_check_caps() after calling __prep_cap(). __prep_cap() is where\narg-\u003exattr_buf is assigned to ci-\u003ei_xattrs.blob. This is the spot where\nthe refcount must be increased to prevent \"use after free\" error.",
"id": "GHSA-9xp8-8c5r-6wfh",
"modified": "2024-06-26T00:31:36Z",
"published": "2024-04-03T15:30:42Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-26689"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/70e329b440762390258a6fe8c0de93c9fdd56c77"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7958c1bf5b03c6f1f58e724dbdec93f8f60b96fc"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8180d0c27b93a6eb60da1b08ea079e3926328214"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ae20db45e482303a20e56f2db667a9d9c54ac7e7"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cda4672da1c26835dcbd7aec2bfed954eda9b5ef"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f3f98d7d84b31828004545e29fd7262b9f444139"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html"
}
],
"schema_version": "1.4.0",
"severity": []
}