GHSA-G582-9MPV-VV22
Vulnerability from github – Published: 2024-05-21 18:31 – Updated: 2024-10-17 15:31In the Linux kernel, the following vulnerability has been resolved:
gfs2: ignore negated quota changes
When lots of quota changes are made, there may be cases in which an inode's quota information is increased and then decreased, such as when blocks are added to a file, then deleted from it. If the timing is right, function do_qc can add pending quota changes to a transaction, then later, another call to do_qc can negate those changes, resulting in a net gain of 0. The quota_change information is recorded in the qc buffer (and qd element of the inode as well). The buffer is added to the transaction by the first call to do_qc, but a subsequent call changes the value from non-zero back to zero. At that point it's too late to remove the buffer_head from the transaction. Later, when the quota sync code is called, the zero-change qd element is discovered and flagged as an assert warning. If the fs is mounted with errors=panic, the kernel will panic.
This is usually seen when files are truncated and the quota changes are negated by punch_hole/truncate which uses gfs2_quota_hold and gfs2_quota_unhold rather than block allocations that use gfs2_quota_lock and gfs2_quota_unlock which automatically do quota sync.
This patch solves the problem by adding a check to qd_check_sync such that net-zero quota changes already added to the transaction are no longer deemed necessary to be synced, and skipped.
In this case references are taken for the qd and the slot from do_qc so those need to be put. The normal sequence of events for a normal non-zero quota change is as follows:
gfs2_quota_change do_qc qd_hold slot_hold
Later, when the changes are to be synced:
gfs2_quota_sync qd_fish qd_check_sync gets qd ref via lockref_get_not_dead do_sync do_qc(QC_SYNC) qd_put lockref_put_or_lock qd_unlock qd_put lockref_put_or_lock
In the net-zero change case, we add a check to qd_check_sync so it puts the qd and slot references acquired in gfs2_quota_change and skip the unneeded sync.
{
"affected": [],
"aliases": [
"CVE-2023-52759"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-21T16:15:15Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ngfs2: ignore negated quota changes\n\nWhen lots of quota changes are made, there may be cases in which an\ninode\u0027s quota information is increased and then decreased, such as when\nblocks are added to a file, then deleted from it. If the timing is\nright, function do_qc can add pending quota changes to a transaction,\nthen later, another call to do_qc can negate those changes, resulting\nin a net gain of 0. The quota_change information is recorded in the qc\nbuffer (and qd element of the inode as well). The buffer is added to the\ntransaction by the first call to do_qc, but a subsequent call changes\nthe value from non-zero back to zero. At that point it\u0027s too late to\nremove the buffer_head from the transaction. Later, when the quota sync\ncode is called, the zero-change qd element is discovered and flagged as\nan assert warning. If the fs is mounted with errors=panic, the kernel\nwill panic.\n\nThis is usually seen when files are truncated and the quota changes are\nnegated by punch_hole/truncate which uses gfs2_quota_hold and\ngfs2_quota_unhold rather than block allocations that use gfs2_quota_lock\nand gfs2_quota_unlock which automatically do quota sync.\n\nThis patch solves the problem by adding a check to qd_check_sync such\nthat net-zero quota changes already added to the transaction are no\nlonger deemed necessary to be synced, and skipped.\n\nIn this case references are taken for the qd and the slot from do_qc\nso those need to be put. The normal sequence of events for a normal\nnon-zero quota change is as follows:\n\ngfs2_quota_change\n do_qc\n qd_hold\n slot_hold\n\nLater, when the changes are to be synced:\n\ngfs2_quota_sync\n qd_fish\n qd_check_sync\n gets qd ref via lockref_get_not_dead\n do_sync\n do_qc(QC_SYNC)\n qd_put\n\t lockref_put_or_lock\n qd_unlock\n qd_put\n lockref_put_or_lock\n\nIn the net-zero change case, we add a check to qd_check_sync so it puts\nthe qd and slot references acquired in gfs2_quota_change and skip the\nunneeded sync.",
"id": "GHSA-g582-9mpv-vv22",
"modified": "2024-10-17T15:31:07Z",
"published": "2024-05-21T18:31:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-52759"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/119565e566f91ff3588ffcd5812f0c8061586c6b"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1c28dace66015b675a343b89b0c87abbfda05ff4"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/212f112fe5e90e98eb8d48585682880dae139f4c"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2a054b87a1b799b391e578597a42ee6e57a987ae"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2bb42a27a92ff3984c9fa5fbe128eced3ea693f2"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/4c6a08125f2249531ec01783a5f4317d7342add5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/50e33567bc4a1c4ed79a1d289fe93c9a26491848"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/53fc16c1ad84f5467ec24341670b63aa759335d3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5bfda356e903633d16ae1bac1ee38364e12628a3"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b4deec69fe32b58dc5fb4ace52456ece85b75561"
}
],
"schema_version": "1.4.0",
"severity": []
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.