vfio/mlx5: Fix racy bitfields and tighten struct layout
Summary
| CVE | CVE-2026-64472 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-07-25 10:17:32 UTC |
| Updated | 2026-07-25 10:17:32 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: vfio/mlx5: Fix racy bitfields and tighten struct layout Bitfield operations are not atomic, they use a read-modify-write pattern, therefore we should be careful not to pack bitfields that can be concurrently updated into the same storage unit. This split takes a binary approach: flags that are only modified pre/post open/close remain bitfields, flags modified from user action, including actions that reach across to another device (ex. reset) use dedicated storage units. Note mlx5_vhca_page_tracker.status is relocated to fill the alignment hole this split exposes. Bitfield justifications: migrate_cap: written only in mlx5vf_cmd_set_migratable() at probe chunk_mode: written only in mlx5vf_cmd_set_migratable() at probe mig_state_cap: written only in mlx5vf_cmd_set_migratable() at probe Dedicated storage units: mdev_detach: written in the VF attach/detach event notifier mlx5fv_vf_event() at runtime log_active: written in mlx5vf_start_page_tracker()/ mlx5vf_stop_page_tracker() during runtime dirty tracking deferred_reset: written in mlx5vf_state_mutex_unlock()/ mlx5vf_pci_aer_reset_done() during runtime reset handling is_err: set by tracker error handling and dirty-log polling at runtime object_changed: set by tracker event handling and cleared by dirty-log polling at runtime |
Risk And Classification
EPSS: 0.001810000 probability, percentile 0.079690000 (date 2026-07-28)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f 1dd99b8f4e143592e12e5a77e7b538bc698116cb git | Not specified |
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f f1db80a67da928a92ba460ede1be52d8941f46be git | Not specified |
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f 399d806f998f7a25405fc1b97227e579aead24af git | Not specified |
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f 7ed120b1a007bace57c461805519d70e1af44e59 git | Not specified |
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f 39d163627b51886492bf31f66cb02c94613d2287 git | Not specified |
| CNA | Linux | Linux | affected 61a2f1460fd03285ea34c1a235f2f50f71e13a1f f2365a63b02ddea32e7db78b742c2503ec7b81f1 git | Not specified |
| CNA | Linux | Linux | affected 5.19 | Not specified |
| CNA | Linux | Linux | unaffected 5.19 semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.178 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.145 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-rc2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/399d806f998f7a25405fc1b97227e579aead24af | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/1dd99b8f4e143592e12e5a77e7b538bc698116cb | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/f2365a63b02ddea32e7db78b742c2503ec7b81f1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/39d163627b51886492bf31f66cb02c94613d2287 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/f1db80a67da928a92ba460ede1be52d8941f46be | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/7ed120b1a007bace57c461805519d70e1af44e59 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| 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.