In the Linux kernel, the following vulnerability has been resolved: virtio-blk: don't keep queue frozen during system suspend Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's PM callbacks. And the motivation is to drain inflight IOs before suspending. block layer's queue freeze looks very handy, but it is also easy to cause deadlock, such as, any attempt to call into bio_queue_enter() may run into deadlock if the queue is frozen in current context. There are all kinds of ->suspend() called in suspend context, so keeping queue frozen in the whole suspend context isn't one good idea. And Marek reported lockdep warning[1] caused by virtio-blk's freeze queue in virtblk_freeze(). [1] https://lore.kernel.org/linux-block/[email protected]/ Given the motivation is to drain in-flight IOs, it can be done by calling freeze & unfreeze, meantime restore to previous behavior by keeping queue quiesced during suspend.
| Métrique | Valeur | Interprétation |
|---|---|---|
|
AV (Vecteur d'Attaque)
Attack Vector
|
Local (L)
|
Exploit nécessite un accès local au système |
|
AC (Complexité d'Attaque)
Attack Complexity
|
Low (L)
|
Peu de conditions requises pour exploiter |
|
PR (Privilèges Requis)
Privileges Required
|
Low (L)
|
Authentifié avec compte utilisateur basique |
|
UI (Interaction Utilisateur)
User Interaction
|
None (N)
|
Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
|
Unchanged (U)
|
Impact reste dans le périmètre du composant compromis |
|
C (Impact Confidentialité)
Confidentiality Impact
|
None (N)
|
Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
|
None (N)
|
Aucune modification de données possible |
|
A (Impact Disponibilité)
Availability Impact
|
High (H)
|
Interruption totale du service possible |
virtio-blk: don't keep queue frozen during system suspend