From 993198b3dea8fdf032e5ff4f0914b203e0f3b67d Mon Sep 17 00:00:00 2001 From: Alexander Potapenko Date: Fri, 30 Jan 2026 14:50:32 +0100 Subject: sys/linux/test: add test for nested SYZOS resumption Add sys/linux/test/amd64-syz_kvm_nested_load_syzos-vmresume to verify the state preservation and resumption capabilities of the SYZOS_API_NESTED_LOAD_SYZOS primitive. The test deploys an L2 guest with a sequential multi-step payload: 1. `uexit(1)` 2. `uexit(2)` The L1 hypervisor first executes `nested_vmlaunch`, causing L2 to run until the first uexit. L1 then executes `nested_vmresume` to continue L2 execution. --- .../test/amd64-syz_kvm_nested_load_syzos-vmresume | 26 ++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 sys/linux/test/amd64-syz_kvm_nested_load_syzos-vmresume (limited to 'sys/linux/test') diff --git a/sys/linux/test/amd64-syz_kvm_nested_load_syzos-vmresume b/sys/linux/test/amd64-syz_kvm_nested_load_syzos-vmresume new file mode 100644 index 000000000..3147476d5 --- /dev/null +++ b/sys/linux/test/amd64-syz_kvm_nested_load_syzos-vmresume @@ -0,0 +1,26 @@ +# +# requires: arch=amd64 -threaded +# +r0 = openat$kvm(0, &AUTO='/dev/kvm\x00', 0x0, 0x0) +r1 = ioctl$KVM_CREATE_VM(r0, AUTO, 0x0) +r2 = syz_kvm_setup_syzos_vm$x86(r1, &(0x7f0000c00000/0x400000)=nil) + +# L2 payload: uexit(1), uexit(2) +# L1 logic: launch (runs 1st uexit), resume (runs 2nd uexit) +# +r3 = syz_kvm_add_vcpu$x86(r2, &AUTO={0x0, &AUTO=[@enable_nested={AUTO, AUTO, 0x0}, @nested_create_vm={AUTO, AUTO, 0x0}, @nested_load_syzos={AUTO, AUTO, {0x0, 0x10, [@uexit={AUTO, AUTO, 0x1}, @uexit={AUTO, AUTO, 0x2}]}}, @nested_vmlaunch={AUTO, AUTO, 0x0}, @nested_vmresume={AUTO, AUTO, 0x0}], AUTO}) +r4 = ioctl$KVM_GET_VCPU_MMAP_SIZE(r0, AUTO) +r5 = mmap$KVM_VCPU(&(0x7f0000009000/0x1000)=nil, r4, 0x3, 0x1, r3, 0x0) + +# L2 Exit 1 +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$x86(r3, r5, 0x0100000000000001) + +# L2 Exit 2 (via VMRESUME) +# +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$x86(r3, r5, 0x0100000000000002) + +ioctl$KVM_RUN(r3, AUTO, 0x0) +syz_kvm_assert_syzos_uexit$x86(r3, r5, 0xffffffffffffffff) -- cgit mrf-deployment