Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: mshv: Fix race in mshv_irqfd_deassign mshv_irqfd_deactivate() and the hlist traversal of pt_irqfds_list require pt->pt_irqfds_lock to be held, but mshv_irqfd_deassign() omits it. This races with the EPOLLHUP path in mshv_irqfd_wakeup(), which does take the lock before calling mshv_irqfd_deactivate(). Additionally, mshv_irqfd_deactivate() uses hlist_del() which poisons the node pointers rather than resetting them. Since mshv_irqfd_is_active() relies on hlist_unhashed() (checks pprev == NULL), a poisoned node still appears active. If a concurrent path calls mshv_irqfd_deactivate() again on the same irqfd, the guard fails to prevent a double hlist_del() on poisoned pointers. Fix both issues: - Add the missing spin_lock_irq/spin_unlock_irq around the list traversal in mshv_irqfd_deassign(), matching mshv_irqfd_release(). - Use hlist_del_init() instead of hlist_del() so the node is properly marked as unhashed after removal, making the is_active guard reliable.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 621191d709b14882270dfd8ea5d7d6cdfebe2c35 before 72a90ce4918b5a2d4820fe20677ba9af780d8826; affected 621191d709b14882270dfd8ea5d7d6cdfebe2c35 before 4529a41a675b96e0f876eef1cc93a31a57cb4d18; affected 621191d709b14882270dfd8ea5d7d6cdfebe2c35 before 0762262ac3e70f65b3bb843fe892f8bac1562d08 |
| Linux / Linux | affected 6.15; unaffected 0 before 6.15; unaffected 6.18.44 through 6.18.*; unaffected 7.1.8 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.