In the Linux kernel, the following vulnerability has been resolved: io_uring: lock overflowing for IOPOLL syzbot reports an issue with overflow filling for IOPOLL: WARNING: CPU: 0 PID: 28 at io_uring/io_uring.c:734 io_cqring_event_overflow+0x1c0/0x230 io_uring/io_uring.c:734 CPU: 0 PID: 28 Comm: kworker/u4:1 Not tainted 6.2.0-rc3-syzkaller-16369-g358a161a6a9e #0 Workqueue: events_unbound io_ring_exit_work Call trace: Â io_cqring_event_overflow+0x1c0/0x230 io_uring/io_uring.c:734 Â io_req_cqe_overflow+0x5c/0x70 io_uring/io_uring.c:773 Â io_fill_cqe_req io_uring/io_uring.h:168 [inline] Â io_do_iopoll+0x474/0x62c io_uring/rw.c:1065 Â io_iopoll_try_reap_events+0x6c/0x108 io_uring/io_uring.c:1513 Â io_uring_try_cancel_requests+0x13c/0x258 io_uring/io_uring.c:3056 Â io_ring_exit_work+0xec/0x390 io_uring/io_uring.c:2869 Â process_one_work+0x2d8/0x504 kernel/workqueue.c:2289 Â worker_thread+0x340/0x610 kernel/workqueue.c:2436 Â kthread+0x12c/0x158 kernel/kthread.c:376 Â ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:863 There is no real problem for normal IOPOLL as flush is also called with uring_lock taken, but it's getting more complicated for IOPOLL|SQPOLL, for which __io_cqring_overflow_flush() happens from the CQ waiting path.
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
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Local (L)
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Exploit nécessite un accès local au système |
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AC (Complexité d'Attaque)
Attack Complexity
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Low (L)
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Peu de conditions requises pour exploiter |
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PR (Privilèges Requis)
Privileges Required
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Low (L)
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Authentifié avec compte utilisateur basique |
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UI (Interaction Utilisateur)
User Interaction
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None (N)
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Aucune interaction utilisateur nécessaire |
|
S (Périmètre)
Scope
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Unchanged (U)
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Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
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None (N)
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Aucune divulgation d'informations |
|
I (Impact Intégrité)
Integrity Impact
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None (N)
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Aucune modification de données possible |
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A (Impact Disponibilité)
Availability Impact
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High (H)
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Interruption totale du service possible |