GHSA-3WRG-MVH6-9V25
Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31In 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
{
"affected": [],
"aliases": [
"CVE-2026-64472"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-25T10:17:32Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/mlx5: Fix racy bitfields and tighten struct layout\n\nBitfield operations are not atomic, they use a read-modify-write\npattern, therefore we should be careful not to pack bitfields that\ncan be concurrently updated into the same storage unit.\n\nThis split takes a binary approach: flags that are only modified\npre/post open/close remain bitfields, flags modified from user\naction, including actions that reach across to another device (ex.\nreset) use dedicated storage units.\n\nNote mlx5_vhca_page_tracker.status is relocated to fill the alignment\nhole this split exposes.\n\nBitfield justifications:\n\n migrate_cap: written only in mlx5vf_cmd_set_migratable() at probe\n chunk_mode: written only in mlx5vf_cmd_set_migratable() at probe\n mig_state_cap: written only in mlx5vf_cmd_set_migratable() at probe\n\nDedicated storage units:\n\n mdev_detach: written in the VF attach/detach event notifier\n mlx5fv_vf_event() at runtime\n log_active: written in mlx5vf_start_page_tracker()/\n mlx5vf_stop_page_tracker() during runtime dirty tracking\n deferred_reset: written in mlx5vf_state_mutex_unlock()/\n mlx5vf_pci_aer_reset_done() during runtime reset handling\n is_err: set by tracker error handling and dirty-log polling at runtime\n object_changed: set by tracker event handling and cleared by dirty-log\n polling at runtime",
"id": "GHSA-3wrg-mvh6-9v25",
"modified": "2026-07-25T12:31:37Z",
"published": "2026-07-25T12:31:37Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64472"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/1dd99b8f4e143592e12e5a77e7b538bc698116cb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/399d806f998f7a25405fc1b97227e579aead24af"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/39d163627b51886492bf31f66cb02c94613d2287"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7ed120b1a007bace57c461805519d70e1af44e59"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f1db80a67da928a92ba460ede1be52d8941f46be"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f2365a63b02ddea32e7db78b742c2503ec7b81f1"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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