From 495f1888134f76a22197deb4b807352ac6b6bb39 Mon Sep 17 00:00:00 2001 From: Muminul Islam Date: Wed, 14 Aug 2024 17:20:38 -0700 Subject: [PATCH] mshv-ioctls: test case to validate map VP state page Add a new test case to test the vp_run method that uses mapped registers page and hv_message page. Signed-off-by: Muminul Islam --- mshv-ioctls/src/ioctls/vcpu.rs | 193 +++++++++++++++++++++++++++++++++ 1 file changed, 193 insertions(+) diff --git a/mshv-ioctls/src/ioctls/vcpu.rs b/mshv-ioctls/src/ioctls/vcpu.rs index 437ed42..0c06c37 100644 --- a/mshv-ioctls/src/ioctls/vcpu.rs +++ b/mshv-ioctls/src/ioctls/vcpu.rs @@ -1544,6 +1544,199 @@ mod tests { unsafe { libc::munmap(load_addr as *mut c_void, mem_size) }; } + #[cfg(target_arch = "x86_64")] + #[test] + fn test_run_code_mmap() { + use super::*; + use crate::ioctls::system::Mshv; + use crate::set_bits; + use libc::c_void; + use std::io::Write; + + let mshv = Mshv::new().unwrap(); + let vm = mshv.create_vm().unwrap(); + let vcpu = vm.create_vcpu(0).unwrap(); + // This example is based on https://lwn.net/Articles/658511/ + #[rustfmt::skip] + let code:[u8;11] = [ + 0xba, 0xf8, 0x03, /* mov $0x3f8, %dx */ + 0x00, 0xd8, /* add %bl, %al */ + 0x04, b'0', /* add $'0', %al */ + 0xee, /* out %al, (%dx) */ + /* send a 0 to indicate we're done */ + 0xb0, b'\0', /* mov $'\0', %al */ + 0xee, /* out %al, (%dx) */ + ]; + + let mem_size = 0x4000; + let load_addr = unsafe { + libc::mmap( + std::ptr::null_mut(), + mem_size, + libc::PROT_READ | libc::PROT_WRITE, + libc::MAP_ANONYMOUS | libc::MAP_SHARED | libc::MAP_NORESERVE, + -1, + 0, + ) + } as *mut u8; + let mem_region = mshv_user_mem_region { + flags: set_bits!(u8, MSHV_SET_MEM_BIT_WRITABLE, MSHV_SET_MEM_BIT_EXECUTABLE), + guest_pfn: 0x1, + size: 0x1000, + userspace_addr: load_addr as u64, + ..Default::default() + }; + + let registers_addr = unsafe { + libc::mmap( + std::ptr::null_mut(), + 0x1000, + libc::PROT_READ | libc::PROT_WRITE, + libc::MAP_SHARED, + vcpu.as_raw_fd(), + MSHV_VP_MMAP_OFFSET_REGISTERS as i64 * libc::sysconf(libc::_SC_PAGE_SIZE), + ) + } as *mut u8; + + if registers_addr as *mut c_void == libc::MAP_FAILED { + panic!( + "Could not mmap register page, error:{}", + std::io::Error::last_os_error() + ); + } + + let hv_msg_addr = unsafe { + libc::mmap( + std::ptr::null_mut(), + 0x1000, + libc::PROT_READ | libc::PROT_WRITE, + libc::MAP_SHARED, + vcpu.as_raw_fd(), + MSHV_VP_MMAP_OFFSET_INTERCEPT_MESSAGE as i64 * libc::sysconf(libc::_SC_PAGE_SIZE), + ) + } as *mut u8; + + if hv_msg_addr as *mut c_void == libc::MAP_FAILED { + panic!( + "Could not mmap HV page, error:{}", + std::io::Error::last_os_error() + ); + } + + vm.map_user_memory(mem_region).unwrap(); + + let reg_page: *mut hv_vp_register_page = registers_addr as *mut hv_vp_register_page; + let hv_msg_page: *mut hv_message = hv_msg_addr as *mut hv_message; + let mut done = false; + + unsafe { + // Get a mutable slice of `mem_size` from `load_addr`. + // This is safe because we mapped it before. + let mut slice = slice::from_raw_parts_mut(load_addr, mem_size); + slice.write_all(&code).unwrap(); + } + + // Get CS Register + let mut cs_reg = hv_register_assoc { + name: hv_register_name_HV_X64_REGISTER_CS, + ..Default::default() + }; + vcpu.get_reg(slice::from_mut(&mut cs_reg)).unwrap(); + + unsafe { + assert_ne!({ cs_reg.value.segment.base }, 0); + assert_ne!({ cs_reg.value.segment.selector }, 0); + }; + + cs_reg.value.segment.base = 0; + cs_reg.value.segment.selector = 0; + + vcpu.set_reg(&[ + cs_reg, + hv_register_assoc { + name: hv_register_name_HV_X64_REGISTER_RAX, + value: hv_register_value { reg64: 2 }, + ..Default::default() + }, + hv_register_assoc { + name: hv_register_name_HV_X64_REGISTER_RBX, + value: hv_register_value { reg64: 2 }, + ..Default::default() + }, + hv_register_assoc { + name: hv_register_name_HV_X64_REGISTER_RIP, + value: hv_register_value { reg64: 0x1000 }, + ..Default::default() + }, + hv_register_assoc { + name: hv_register_name_HV_X64_REGISTER_RFLAGS, + value: hv_register_value { reg64: 0x2 }, + ..Default::default() + }, + ]) + .unwrap(); + + unsafe { + assert!((*reg_page).version == HV_VP_REGISTER_PAGE_VERSION_1 as u16); + assert!((*reg_page).isvalid == 1); + assert!((*reg_page).dirty == 0); + } + + loop { + vcpu.run().unwrap(); + let msg_header = unsafe { (*hv_msg_page).header }; + match msg_header.message_type { + hv_message_type_HVMSG_X64_HALT => { + println!("VM Halted!"); + break; + } + hv_message_type_HVMSG_X64_IO_PORT_INTERCEPT => { + let io_message = unsafe { (*hv_msg_page).to_ioport_info().unwrap() }; + assert!(io_message.port_number == 0x3f8); + unsafe { + assert!(io_message.access_info.__bindgen_anon_1.string_op() == 0); + assert!(io_message.access_info.__bindgen_anon_1.access_size() == 1); + } + if !done { + assert!(io_message.rax == b'4' as u64); + assert!(io_message.port_number == 0x3f8); + unsafe { + assert!(io_message.access_info.__bindgen_anon_1.string_op() == 0); + assert!(io_message.access_info.__bindgen_anon_1.access_size() == 1); + } + assert!( + io_message.header.intercept_access_type == /*HV_INTERCEPT_ACCESS_WRITE*/ 1_u8 + ); + done = true; + /* Advance rip */ + unsafe { + (*reg_page).__bindgen_anon_1.__bindgen_anon_1.rip = + io_message.header.rip + 1; + } + unsafe { + (*reg_page).dirty = 1 << HV_X64_REGISTER_CLASS_IP; + } + } else { + assert!(io_message.rax == b'\0' as u64); + assert!( + io_message.header.intercept_access_type == /*HV_INTERCEPT_ACCESS_WRITE*/ 1_u8 + ); + break; + } + } + _ => { + println!("Message type: 0x{:x?}", { msg_header.message_type }); + panic!("Unexpected Exit Type"); + } + }; + } + assert!(done); + + vm.unmap_user_memory(mem_region).unwrap(); + unsafe { libc::munmap(load_addr as *mut c_void, mem_size) }; + unsafe { libc::munmap(registers_addr as *mut c_void, 0x1000) }; + unsafe { libc::munmap(hv_msg_addr as *mut c_void, 0x1000) }; + } #[test] fn test_set_get_msrs() { let hv = Mshv::new().unwrap();