bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized
Summary
| CVE | CVE-2026-64192 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-20 17:18:22 UTC |
| Updated | 2026-08-23 13:16:30 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized When CONFIG_BPF_LSM=y is set, BPF inode storage maps (BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However, if the BPF LSM is not explicitly enabled at boot time (e.g. omitted from the "lsm=" boot parameter), lsm_prepare() is never executed for the BPF LSM. Consequently, the BPF inode security blob offset (bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at its default compiled size of 8 bytes instead of being updated to a valid offset past the reserved struct rcu_head (typically 16 bytes or more). When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE map, bpf_inode() evaluates inode->i_security + 8. This erroneously aliases the struct rcu_head.func callback pointer at the beginning of the inode->i_security blob. During subsequent map element cleanup or inode destruction, writing NULL to owner_storage clears the queued RCU callback pointer. When rcu_do_batch() later executes the queued callback, it attempts an instruction fetch at address 0x0, triggering an immediate kernel panic. Fix this by introducing a global bpf_lsm_initialized boolean flag marked with __ro_after_init. Set this flag to true inside bpf_lsm_init() when the LSM framework successfully registers the BPF LSM. Gate map allocation in inode_storage_map_alloc() on this flag, returning -EOPNOTSUPP if the BPF LSM is in turn uninitialized. This fail-fast approach prevents userspace from allocating inode storage maps when the supporting BPF LSM infrastructure is absent, avoiding zombie map states. |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.001620000 probability, percentile 0.058700000 (date 2026-08-04)
Problem Types: CWE-476
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
LowUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Linux | Linux Kernel | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 413b14b9623a2e6ee131c2b2152b304aeb04e378 git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 a6d634f794c808a261eac7d5af023a7e06b9ecd8 git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 721f669853bdbf46b475a81bb5d05d610f8c19de git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 5337eebdf8c5d4810b1913047f078d2815d5645f git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 de984ea883405420fdc416ae8964b752df586970 git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 267fdd9b6530c399dfd996e1a0a7628b45baf9f0 git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 c76b8abce575e0c6e4096957220b4515ed847d89 git | Not specified |
| CNA | Linux | Linux | affected 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 git | Not specified |
| CNA | Linux | Linux | affected 5.10 | Not specified |
| CNA | Linux | Linux | unaffected 5.10 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.266 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.217 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.184 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.148 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.97 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.40 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.4 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/267fdd9b6530c399dfd996e1a0a7628b45baf9f0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/c76b8abce575e0c6e4096957220b4515ed847d89 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/a6d634f794c808a261eac7d5af023a7e06b9ecd8 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/721f669853bdbf46b475a81bb5d05d610f8c19de | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/de984ea883405420fdc416ae8964b752df586970 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| git.kernel.org/stable/c/413b14b9623a2e6ee131c2b2152b304aeb04e378 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/5337eebdf8c5d4810b1913047f078d2815d5645f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | Patch |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.