SRCU uses a delayed work item. Skip cleaning it up, and the result is use-after-free in the work item callbacks. Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Suggested-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Fixes: 0eb05bf290cfe8610d9680b49abef37febd1c38a Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> --- arch/x86/include/asm/kvm_page_track.h | 1 + arch/x86/kvm/page_track.c | 8 ++++++++ arch/x86/kvm/x86.c | 1 + 3 files changed, 10 insertions(+) diff --git a/arch/x86/include/asm/kvm_page_track.h b/arch/x86/include/asm/kvm_page_track.h index d74747b031ec..c4eda791f877 100644 --- a/arch/x86/include/asm/kvm_page_track.h +++ b/arch/x86/include/asm/kvm_page_track.h @@ -46,6 +46,7 @@ struct kvm_page_track_notifier_node { }; void kvm_page_track_init(struct kvm *kvm); +void kvm_page_track_cleanup(struct kvm *kvm); void kvm_page_track_free_memslot(struct kvm_memory_slot *free, struct kvm_memory_slot *dont); diff --git a/arch/x86/kvm/page_track.c b/arch/x86/kvm/page_track.c index 37942e419c32..60168cdd0546 100644 --- a/arch/x86/kvm/page_track.c +++ b/arch/x86/kvm/page_track.c @@ -160,6 +160,14 @@ bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn, return !!ACCESS_ONCE(slot->arch.gfn_track[mode][index]); } +void kvm_page_track_cleanup(struct kvm *kvm) +{ + struct kvm_page_track_notifier_head *head; + + head = &kvm->arch.track_notifier_head; + cleanup_srcu_struct(&head->track_srcu); +} + void kvm_page_track_init(struct kvm *kvm) { struct kvm_page_track_notifier_head *head; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 64697fe475c3..f2379673912a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8070,6 +8070,7 @@ void kvm_arch_sync_events(struct kvm *kvm) cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work); kvm_free_all_assigned_devices(kvm); kvm_free_pit(kvm); + kvm_page_track_cleanup(kvm); } int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size) -- 1.8.3.1