From: Keir Fraser Date: Wed, 15 Sep 2010 15:52:31 +0000 (+0100) Subject: vmx: Annotate update_guest_eip() callers with safety analysis X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~11478 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=817d5500238787a636ec199781b76dd6bbdd218d;p=xen.git vmx: Annotate update_guest_eip() callers with safety analysis for access to VM_EXIT_INSTRUCTION_LEN Signed-off-by: Keir Fraser --- diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index dcc3b8fd29..3aa1a4cff5 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -1434,7 +1434,7 @@ struct hvm_function_table * __init start_vmx(void) * Not all cases receive valid value in the VM-exit instruction length field. * Callers must know what they're doing! */ -static int __get_instruction_length(void) +static int get_instruction_length(void) { int len; len = __vmread(VM_EXIT_INSTRUCTION_LEN); /* Safe: callers audited */ @@ -1442,12 +1442,12 @@ static int __get_instruction_length(void) return len; } -static void __update_guest_eip(unsigned long inst_len) +static void update_guest_eip(void) { struct cpu_user_regs *regs = guest_cpu_user_regs(); unsigned long x; - regs->eip += inst_len; + regs->eip += get_instruction_length(); /* Safe: callers audited */ regs->eflags &= ~X86_EFLAGS_RF; x = __vmread(GUEST_INTERRUPTIBILITY_INFO); @@ -1461,12 +1461,6 @@ static void __update_guest_eip(unsigned long inst_len) vmx_inject_hw_exception(TRAP_debug, HVM_DELIVER_NO_ERROR_CODE); } -static void update_guest_eip(void) -{ - unsigned long inst_len = __get_instruction_length(); - __update_guest_eip(inst_len); -} - static void vmx_fpu_dirty_intercept(void) { struct vcpu *curr = current; @@ -2198,7 +2192,7 @@ static int vmx_handle_eoi_write(void) if ( (((exit_qualification >> 12) & 0xf) == 1) && ((exit_qualification & 0xfff) == APIC_EOI) ) { - update_guest_eip(); + update_guest_eip(); /* Safe: APIC data write */ vlapic_EOI_set(vcpu_vlapic(current)); return 1; } @@ -2384,7 +2378,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) case TRAP_int3: if ( !v->domain->debugger_attached ) goto exit_and_crash; - update_guest_eip(); + update_guest_eip(); /* Safe: INT3 */ current->arch.gdbsx_vcpu_event = TRAP_int3; domain_pause_for_debugger(); break; @@ -2467,7 +2461,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) */ inst_len = ((source != 3) || /* CALL, IRET, or JMP? */ (idtv_info & (1u<<10))) /* IntrType > 3? */ - ? __get_instruction_length() /* Safe: SDM 3B 23.2.4 */ : 0; + ? get_instruction_length() /* Safe: SDM 3B 23.2.4 */ : 0; if ( (source == 3) && (idtv_info & INTR_INFO_DELIVER_CODE_MASK) ) ecode = __vmread(IDT_VECTORING_ERROR_CODE); regs->eip += inst_len; @@ -2475,15 +2469,15 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) break; } case EXIT_REASON_CPUID: - update_guest_eip(); + update_guest_eip(); /* Safe: CPUID */ vmx_do_cpuid(regs); break; case EXIT_REASON_HLT: - update_guest_eip(); + update_guest_eip(); /* Safe: HLT */ hvm_hlt(regs->eflags); break; case EXIT_REASON_INVLPG: - update_guest_eip(); + update_guest_eip(); /* Safe: INVLPG */ exit_qualification = __vmread(EXIT_QUALIFICATION); vmx_invlpg_intercept(exit_qualification); break; @@ -2491,7 +2485,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) regs->ecx = hvm_msr_tsc_aux(v); /* fall through */ case EXIT_REASON_RDTSC: - update_guest_eip(); + update_guest_eip(); /* Safe: RDTSC, RDTSCP */ hvm_rdtsc_intercept(regs); break; case EXIT_REASON_VMCALL: @@ -2501,7 +2495,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) rc = hvm_do_hypercall(regs); if ( rc != HVM_HCALL_preempted ) { - update_guest_eip(); + update_guest_eip(); /* Safe: VMCALL */ if ( rc == HVM_HCALL_invalidate ) send_invalidate_req(); } @@ -2511,7 +2505,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) { exit_qualification = __vmread(EXIT_QUALIFICATION); if ( vmx_cr_access(exit_qualification, regs) ) - update_guest_eip(); + update_guest_eip(); /* Safe: MOV Cn, LMSW, CLTS */ break; } case EXIT_REASON_DR_ACCESS: @@ -2525,7 +2519,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) { regs->eax = (uint32_t)msr_content; regs->edx = (uint32_t)(msr_content >> 32); - update_guest_eip(); + update_guest_eip(); /* Safe: RDMSR */ } break; } @@ -2534,7 +2528,7 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) uint64_t msr_content; msr_content = ((uint64_t)regs->edx << 32) | (uint32_t)regs->eax; if ( hvm_msr_write_intercept(regs->ecx, msr_content) == X86EMUL_OKAY ) - update_guest_eip(); + update_guest_eip(); /* Safe: WRMSR */ break; } @@ -2573,23 +2567,25 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) exit_qualification = __vmread(EXIT_QUALIFICATION); if ( exit_qualification & 0x10 ) { + /* INS, OUTS */ if ( !handle_mmio() ) vmx_inject_hw_exception(TRAP_gp_fault, 0); } else { + /* IN, OUT */ uint16_t port = (exit_qualification >> 16) & 0xFFFF; int bytes = (exit_qualification & 0x07) + 1; int dir = (exit_qualification & 0x08) ? IOREQ_READ : IOREQ_WRITE; if ( handle_pio(port, bytes, dir) ) - update_guest_eip(); + update_guest_eip(); /* Safe: IN, OUT */ } break; case EXIT_REASON_INVD: case EXIT_REASON_WBINVD: { - update_guest_eip(); + update_guest_eip(); /* Safe: INVD, WBINVD */ vmx_wbinvd_intercept(); break; } @@ -2619,11 +2615,9 @@ asmlinkage void vmx_vmexit_handler(struct cpu_user_regs *regs) case EXIT_REASON_XSETBV: { - u64 new_bv = (((u64)regs->edx) << 32) | regs->eax; + u64 new_bv = (((u64)regs->edx) << 32) | regs->eax; if ( vmx_handle_xsetbv(new_bv) == 0 ) - { - update_guest_eip(); - } + update_guest_eip(); /* Safe: XSETBV */ break; }