sched/psi: fix race between file release and pressure write
In the Linux kernel, the following vulnerability has been resolved: sched/psi: fix race between file release and pressure write A potential race condition exists between pressure write and cgroup file release regarding the priv member of struct kernfs_open_file, which triggers the uaf reported in [1]. Consider the following scenario involving execution on two separate CPUs: CPU0 CPU1 ==== ==== vfs_rmdir() kernfs_iop_rmdir() cgroup_rmdir() cgroup_kn_lock_live() cgroup_destroy_locked() cgroup_addrm_files() cgroup_rm_file() kernfs_remove_by_name() kernfs_remove_by_name_ns() vfs_write() __kernfs_remove() new_sync_write() kernfs_drain() kernfs_fop_write_iter() kernfs_drain_open_files() cgroup_file_write() kernfs_release_file() pressure_write() cgroup_file_release() ctx = of->priv; kfree(ctx); of->priv = NULL; cgroup_kn_unlock() cgroup_kn_lock_live() cgroup_get(cgrp) cgroup_kn_unlock() if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv The cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards the memory deallocation of of->priv performed within cgroup_file_release(). However, the operations involving of->priv executed within pressure_write() are not entirely covered by the protection of cgroup_mutex. Consequently, if the code in pressure_write(), specifically the section handling the ctx variable executes after cgroup_file_release() has completed, a uaf vulnerability involving of->priv is triggered. Therefore, the issue can be resolved by extending t
CVE-2026-52991
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-52991
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5",
"lessThan": "d8ddbc3330fa6851c56b046e630a8fc64830a0ce",
"versionType": "git"
},
{
"status": "affected",
"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5",
"lessThan": "af0638534bfae7980582c6482531a0872f8ee341",
"versionType": "git"
},
{
"status": "affected",
"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5",
"lessThan": "03dc070fa0fc3cb4068693f468ccd5f8a7e58282",
"versionType": "git"
},
{
"status": "affected",
"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5",
"lessThan": "d4352c0709bfd38c752fccbde7fd72a82ac78f23",
"versionType": "git"
},
{
"status": "affected",
"version": "0e94682b73bfa6c44c98af7a26771c9c08c055d5",
"lessThan": "a5b98009f16d8a5fb4a8ff9a193f5735515c38fa",
"versionType": "git"
}
],
"programFiles": [
"kernel/cgroup/cgroup.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.114",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.33",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.10",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/cgroup/cgroup.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-52991
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46350 · Revision 1
- Added to Heist Feed
- Publisher date