bpf: Clear rb node linkage when freeing bpf_rb_root
In the Linux kernel, the following vulnerability has been resolved: bpf: Clear rb node linkage when freeing bpf_rb_root bpf_rb_root_free() detaches the root by copying the current rb_root_cached and then replacing the live root with RB_ROOT_CACHED. It then walks the copied root and drops each object contained in the tree. This leaves the rb node state intact while dropping the object. If the object is refcounted and survives the drop, its bpf_rb_node_kern still contains an owner pointer to the freed root and stale rb tree linkage. If a later bpf_rb_root allocation reuses the same address, bpf_rbtree_remove() can incorrectly pass the owner check and call rb_erase_cached() on a node whose rb pointers belong to the old tree. Mirror the list draining behavior by marking nodes as busy while the root is being detached, then clear the rb node and release the owner before dropping the containing object. This makes surviving nodes unowned and safe to reject from remove or accept for a later add.
CVE-2026-74344
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-2026-74344
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": "9c395c1b99bd23f74bc628fa000480c49593d17f",
"lessThan": "628a469d2a73e3844e5ee80aa002e232b0fd6493",
"versionType": "git"
},
{
"status": "affected",
"version": "9c395c1b99bd23f74bc628fa000480c49593d17f",
"lessThan": "ff3ab3fb956027ab40aca1fb3298cf20dc290273",
"versionType": "git"
},
{
"status": "affected",
"version": "9c395c1b99bd23f74bc628fa000480c49593d17f",
"lessThan": "2eb39de4962f842d653e96818ae372665cd481fd",
"versionType": "git"
},
{
"status": "affected",
"version": "9c395c1b99bd23f74bc628fa000480c49593d17f",
"lessThan": "574612793bed416f6c05fe7c9b50e9eb0441997e",
"versionType": "git"
},
{
"status": "affected",
"version": "9c395c1b99bd23f74bc628fa000480c49593d17f",
"lessThan": "4a7910ee060d8ce55612f5b3cc267f3a265a3cec",
"versionType": "git"
},
{
"status": "affected",
"version": "1d0675957d35ac5e514073481beda62e4e1e2ec5",
"versionType": "git"
},
{
"status": "affected",
"version": "6.2.15",
"lessThan": "6.3",
"versionType": "semver"
}
],
"programFiles": [
"kernel/bpf/helpers.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.3"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.3",
"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": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/bpf/helpers.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74344
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #46546 · Revision 1
- Added to Heist Feed
- Publisher date