Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.9 04/16] KVM: x86: cleanup the page tracking SRCU instance | Date | Thu, 30 Mar 2017 12:15:55 +0200 |
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4.9-stable review patch. If anyone has any objections, please let me know.
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From: Paolo Bonzini <pbonzini@redhat.com>
commit 2beb6dad2e8f95d710159d5befb390e4f62ab5cf upstream.
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@google.com> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Fixes: 0eb05bf290cfe8610d9680b49abef37febd1c38a Reviewed-by: Xiao Guangrong <xiaoguangrong.eric@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- 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(+)
--- a/arch/x86/include/asm/kvm_page_track.h +++ b/arch/x86/include/asm/kvm_page_track.h @@ -35,6 +35,7 @@ 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); --- a/arch/x86/kvm/page_track.c +++ b/arch/x86/kvm/page_track.c @@ -156,6 +156,14 @@ bool kvm_page_track_is_active(struct kvm 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; --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7976,6 +7976,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm kvm_free_vcpus(kvm); kvfree(rcu_dereference_check(kvm->arch.apic_map, 1)); kvm_mmu_uninit_vm(kvm); + kvm_page_track_cleanup(kvm); } void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
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