جزئیات آسیب‌پذیری

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: vgic: Check the interrupt is still ours before migrating it vgic_prune_ap_list() drops both ap_list_lock and irq_lock while migrating an interrupt to another vCPU. After reacquiring the locks it only checks that the affinity is unchanged (target_vcpu == vgic_target_oracle(irq)) before moving the interrupt, which assumes that an interrupt whose affinity is preserved is still queued on this vCPU's ap_list. That assumption no longer holds if the interrupt is taken off the ap_list while the locks are dropped. vgic_flush_pending_lpis() removes the interrupt from the list and sets irq->vcpu to NULL, but leaves enabled/pending/target_vcpu untouched. As the interrupt is still enabled and pending, vgic_target_oracle() returns the same target_vcpu, so the affinity check passes and list_del() is run a second time on an entry that has already been removed. Also check that the interrupt is still assigned to this vCPU (irq->vcpu == vcpu) before moving it.

• https://git.kernel.org/stable/c/3893e1fcf6f306b327a8358dcd1cbd077989a240
• https://git.kernel.org/stable/c/cb3efe1a354f1638726725c3ecee1ce8d1a7e2dc
• https://git.kernel.org/stable/c/da2d249a39a1881681c303ceea33f38ba1c5bbeb
• https://git.kernel.org/stable/c/654be81c4c637af12709d47c7efc3302cd336513
• https://git.kernel.org/stable/c/e363c0bc0226dc5ea5046a88e9a6864b82c45399
• https://git.kernel.org/stable/c/79fdd2aa774e44847cd9bb7edc811e73e3dc7bfe
• https://git.kernel.org/stable/c/0658b09cba7fe866c6cd70cd2dcdfdcabe80328f
• https://git.kernel.org/stable/c/0074b82cdfcb5fd13710a0ac308ade68ac6f6fbe