{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-53195","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2024-11-19T17:17:25.014Z","datePublished":"2024-12-27T13:49:37.514Z","dateUpdated":"2025-12-20T08:51:41.553Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2025-12-20T08:51:41.553Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Get rid of userspace_irqchip_in_use\n\nImproper use of userspace_irqchip_in_use led to syzbot hitting the\nfollowing WARN_ON() in kvm_timer_update_irq():\n\nWARNING: CPU: 0 PID: 3281 at arch/arm64/kvm/arch_timer.c:459\nkvm_timer_update_irq+0x21c/0x394\nCall trace:\n  kvm_timer_update_irq+0x21c/0x394 arch/arm64/kvm/arch_timer.c:459\n  kvm_timer_vcpu_reset+0x158/0x684 arch/arm64/kvm/arch_timer.c:968\n  kvm_reset_vcpu+0x3b4/0x560 arch/arm64/kvm/reset.c:264\n  kvm_vcpu_set_target arch/arm64/kvm/arm.c:1553 [inline]\n  kvm_arch_vcpu_ioctl_vcpu_init arch/arm64/kvm/arm.c:1573 [inline]\n  kvm_arch_vcpu_ioctl+0x112c/0x1b3c arch/arm64/kvm/arm.c:1695\n  kvm_vcpu_ioctl+0x4ec/0xf74 virt/kvm/kvm_main.c:4658\n  vfs_ioctl fs/ioctl.c:51 [inline]\n  __do_sys_ioctl fs/ioctl.c:907 [inline]\n  __se_sys_ioctl fs/ioctl.c:893 [inline]\n  __arm64_sys_ioctl+0x108/0x184 fs/ioctl.c:893\n  __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]\n  invoke_syscall+0x78/0x1b8 arch/arm64/kernel/syscall.c:49\n  el0_svc_common+0xe8/0x1b0 arch/arm64/kernel/syscall.c:132\n  do_el0_svc+0x40/0x50 arch/arm64/kernel/syscall.c:151\n  el0_svc+0x54/0x14c arch/arm64/kernel/entry-common.c:712\n  el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730\n  el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598\n\nThe following sequence led to the scenario:\n - Userspace creates a VM and a vCPU.\n - The vCPU is initialized with KVM_ARM_VCPU_PMU_V3 during\n   KVM_ARM_VCPU_INIT.\n - Without any other setup, such as vGIC or vPMU, userspace issues\n   KVM_RUN on the vCPU. Since the vPMU is requested, but not setup,\n   kvm_arm_pmu_v3_enable() fails in kvm_arch_vcpu_run_pid_change().\n   As a result, KVM_RUN returns after enabling the timer, but before\n   incrementing 'userspace_irqchip_in_use':\n   kvm_arch_vcpu_run_pid_change()\n       ret = kvm_arm_pmu_v3_enable()\n           if (!vcpu->arch.pmu.created)\n               return -EINVAL;\n       if (ret)\n           return ret;\n       [...]\n       if (!irqchip_in_kernel(kvm))\n           static_branch_inc(&userspace_irqchip_in_use);\n - Userspace ignores the error and issues KVM_ARM_VCPU_INIT again.\n   Since the timer is already enabled, control moves through the\n   following flow, ultimately hitting the WARN_ON():\n   kvm_timer_vcpu_reset()\n       if (timer->enabled)\n          kvm_timer_update_irq()\n              if (!userspace_irqchip())\n                  ret = kvm_vgic_inject_irq()\n                      ret = vgic_lazy_init()\n                          if (unlikely(!vgic_initialized(kvm)))\n                              if (kvm->arch.vgic.vgic_model !=\n                                  KVM_DEV_TYPE_ARM_VGIC_V2)\n                                      return -EBUSY;\n                  WARN_ON(ret);\n\nTheoretically, since userspace_irqchip_in_use's functionality can be\nsimply replaced by '!irqchip_in_kernel()', get rid of the static key\nto avoid the mismanagement, which also helps with the syzbot issue."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kvm_host.h","arch/arm64/kvm/arch_timer.c","arch/arm64/kvm/arm.c"],"versions":[{"version":"6211753fdfd05af9e08f54c8d0ba3ee516034878","lessThan":"dd2f9861f27571d47998d71e7516bf7216db0b52","status":"affected","versionType":"git"},{"version":"6211753fdfd05af9e08f54c8d0ba3ee516034878","lessThan":"c16e2dba39ff6ae84bb8dc9c8e0fb21d9b2f6f5c","status":"affected","versionType":"git"},{"version":"6211753fdfd05af9e08f54c8d0ba3ee516034878","lessThan":"fe425d5239a28c21e0c83ee7a8f4cb210d29fdb4","status":"affected","versionType":"git"},{"version":"6211753fdfd05af9e08f54c8d0ba3ee516034878","lessThan":"38d7aacca09230fdb98a34194fec2af597e8e20d","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/include/asm/kvm_host.h","arch/arm64/kvm/arch_timer.c","arch/arm64/kvm/arm.c"],"versions":[{"version":"3.11","status":"affected"},{"version":"0","lessThan":"3.11","status":"unaffected","versionType":"semver"},{"version":"6.6.64","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.11.11","lessThanOrEqual":"6.11.*","status":"unaffected","versionType":"semver"},{"version":"6.12.2","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.13","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.6.64"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.11.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.12.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.11","versionEndExcluding":"6.13"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/dd2f9861f27571d47998d71e7516bf7216db0b52"},{"url":"https://git.kernel.org/stable/c/c16e2dba39ff6ae84bb8dc9c8e0fb21d9b2f6f5c"},{"url":"https://git.kernel.org/stable/c/fe425d5239a28c21e0c83ee7a8f4cb210d29fdb4"},{"url":"https://git.kernel.org/stable/c/38d7aacca09230fdb98a34194fec2af597e8e20d"}],"title":"KVM: arm64: Get rid of userspace_irqchip_in_use","x_generator":{"engine":"bippy-1.2.0"}}}}