Lan Tianyu 3a46a033bf KVM/Eventfd: Avoid crash when assign and deassign specific eventfd in parallel. ... commit b5020a8e6b upstream. Syzbot reports crashes in kvm_irqfd_assign(), caused by use-after-free when kvm_irqfd_assign() and kvm_irqfd_deassign() run in parallel for one specific eventfd. When the assign path hasn't finished but irqfd has been added to kvm->irqfds.items list, another thead may deassign the eventfd and free struct kvm_kernel_irqfd(). The assign path then uses the struct kvm_kernel_irqfd that has been freed by deassign path. To avoid such issue, keep irqfd under kvm->irq_srcu protection after the irqfd has been added to kvm->irqfds.items list, and call synchronize_srcu() in irq_shutdown() to make sure that irqfd has been fully initialized in the assign path. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Tianyu Lan <tianyu.lan@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-07-25 11:25:07 +02:00
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kvm	KVM/Eventfd: Avoid crash when assign and deassign specific eventfd in parallel.	2018-07-25 11:25:07 +02:00
lib	KVM: eventfd: fix NULL deref irqbypass consumer	2017-01-12 14:42:34 +01:00
Makefile	virt: Add virt directory to the top Makefile	2015-10-01 15:06:44 +02:00