blk-cgroup: fix leaks and online flag on radix_tree_insert failure
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix leaks and online flag on radix_tree_insert failure When radix_tree_insert() fails in blkg_create(), the error path has two issues: 1. blkg->online is set to true unconditionally, even when the blkg was never fully inserted. Move the assignment inside the success block. 2. The error path calls blkg_put() without first calling percpu_ref_kill(). Because the refcount is still in percpu mode, percpu_ref_put() only does this_cpu_sub() without checking for zero, so blkg_release() is never triggered. This permanently leaks the blkg memory, its percpu iostat, policy data, the parent blkg reference, and the cgroup css reference — the latter preventing the cgroup from ever being destroyed. Fix by replacing blkg_put() with percpu_ref_kill(), matching the pattern used in blkg_destroy().
CVE-2026-93795
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-2026-93795
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": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "0f840db042caee9d2f3dcdcf97d6674f6e4c1e30",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "f53945d7c712efe63fadbcc5ffed6370871fd0d3",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "ada8270ccdb6f212da5eb22614c28ea418746a4a",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "c3650be82ef6e7af13b79b2d10a7363bdf54aa7f",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "6e85f02d45b5977c0326a8d854c6db878aa6b34a",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "4c0d150fb98ea40760611979f4e664c244b20966",
"versionType": "git"
},
{
"status": "affected",
"version": "7fcf2b033b84e261dca283bc2911aaea4b07b525",
"lessThan": "dbbca20764382b4d411ec2918f4e278ffe547acc",
"versionType": "git"
}
],
"programFiles": [
"block/blk-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": "5.0"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.0",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.271",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.222",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.189",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.158",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.111",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.53",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"block/blk-cgroup.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-93795
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #8273 · Revision 1
- Added to Heist Feed
- Publisher date