From mboxrd@z Thu Jan 1 00:00:00 1970 From: Feng Wu Subject: [PATCH v2 2/7] Clear AC bit in RFLAGS to protect Xen itself by SMAP Date: Wed, 23 Apr 2014 22:35:11 +0800 Message-ID: <1398263711-32046-1-git-send-email-feng.wu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: kevin.tian@intel.com, Feng Wu , JBeulich@suse.com, andrew.cooper3@citrix.com, eddie.dong@intel.com, jun.nakajima@intel.com, ian.campbell@citrix.com List-Id: xen-devel@lists.xenproject.org Clear AC bit in RFLAGS at the beginning of exception, interrupt, hypercall, so Xen itself can be protected by SMAP mechanism. Signed-off-by: Feng Wu --- xen/arch/x86/x86_64/compat/entry.S | 1 + xen/arch/x86/x86_64/entry.S | 26 ++++++++++++++++++++++++++ xen/include/asm-x86/x86_64/asm_defns.h | 1 + 3 files changed, 28 insertions(+) diff --git a/xen/arch/x86/x86_64/compat/entry.S b/xen/arch/x86/x86_64/compat/entry.S index 32b3bcc..ac594c9 100644 --- a/xen/arch/x86/x86_64/compat/entry.S +++ b/xen/arch/x86/x86_64/compat/entry.S @@ -13,6 +13,7 @@ #include ENTRY(compat_hypercall) + ASM_CLAC pushq $0 SAVE_VOLATILE type=TRAP_syscall compat=1 diff --git a/xen/arch/x86/x86_64/entry.S b/xen/arch/x86/x86_64/entry.S index 3ea4683..d294064 100644 --- a/xen/arch/x86/x86_64/entry.S +++ b/xen/arch/x86/x86_64/entry.S @@ -120,6 +120,7 @@ restore_all_xen: * the space left by the trampoline. */ ENTRY(syscall_enter) + ASM_CLAC sti movl $FLAT_KERNEL_SS,24(%rsp) pushq %rcx @@ -268,6 +269,7 @@ bad_hypercall: jmp test_all_events ENTRY(sysenter_entry) + ASM_CLAC sti pushq $FLAT_USER_SS pushq $0 @@ -309,6 +311,7 @@ UNLIKELY_END(sysenter_gpf) jmp .Lbounce_exception ENTRY(int80_direct_trap) + ASM_CLAC pushq $0 SAVE_VOLATILE 0x80 @@ -476,6 +479,7 @@ ENTRY(ret_from_intr) jmp compat_test_all_events ENTRY(page_fault) + ASM_CLAC movl $TRAP_page_fault,4(%rsp) /* No special register assumptions. */ GLOBAL(handle_exception) @@ -532,81 +536,98 @@ FATAL_exception_with_ints_disabled: ud2 ENTRY(divide_error) + ASM_CLAC pushq $0 movl $TRAP_divide_error,4(%rsp) jmp handle_exception ENTRY(coprocessor_error) + ASM_CLAC pushq $0 movl $TRAP_copro_error,4(%rsp) jmp handle_exception ENTRY(simd_coprocessor_error) + ASM_CLAC pushq $0 movl $TRAP_simd_error,4(%rsp) jmp handle_exception ENTRY(device_not_available) + ASM_CLAC pushq $0 movl $TRAP_no_device,4(%rsp) jmp handle_exception ENTRY(debug) + ASM_CLAC pushq $0 movl $TRAP_debug,4(%rsp) jmp handle_exception ENTRY(int3) + ASM_CLAC pushq $0 movl $TRAP_int3,4(%rsp) jmp handle_exception ENTRY(overflow) + ASM_CLAC pushq $0 movl $TRAP_overflow,4(%rsp) jmp handle_exception ENTRY(bounds) + ASM_CLAC pushq $0 movl $TRAP_bounds,4(%rsp) jmp handle_exception ENTRY(invalid_op) + ASM_CLAC pushq $0 movl $TRAP_invalid_op,4(%rsp) jmp handle_exception ENTRY(coprocessor_segment_overrun) + ASM_CLAC pushq $0 movl $TRAP_copro_seg,4(%rsp) jmp handle_exception ENTRY(invalid_TSS) + ASM_CLAC movl $TRAP_invalid_tss,4(%rsp) jmp handle_exception ENTRY(segment_not_present) + ASM_CLAC movl $TRAP_no_segment,4(%rsp) jmp handle_exception ENTRY(stack_segment) + ASM_CLAC movl $TRAP_stack_error,4(%rsp) jmp handle_exception ENTRY(general_protection) + ASM_CLAC movl $TRAP_gp_fault,4(%rsp) jmp handle_exception ENTRY(alignment_check) + ASM_CLAC movl $TRAP_alignment_check,4(%rsp) jmp handle_exception ENTRY(spurious_interrupt_bug) + ASM_CLAC pushq $0 movl $TRAP_spurious_int,4(%rsp) jmp handle_exception ENTRY(double_fault) + ASM_CLAC movl $TRAP_double_fault,4(%rsp) SAVE_ALL movq %rsp,%rdi @@ -615,6 +636,7 @@ ENTRY(double_fault) .pushsection .init.text, "ax", @progbits ENTRY(early_page_fault) + ASM_CLAC SAVE_ALL movq %rsp,%rdi call do_early_page_fault @@ -622,6 +644,7 @@ ENTRY(early_page_fault) .popsection ENTRY(nmi) + ASM_CLAC pushq $0 movl $TRAP_nmi,4(%rsp) handle_ist_exception: @@ -659,6 +682,7 @@ handle_ist_exception: jmp compat_restore_all_guest ENTRY(nmi_crash) + ASM_CLAC pushq $0 movl $TRAP_nmi,4(%rsp) SAVE_ALL @@ -667,6 +691,7 @@ ENTRY(nmi_crash) ud2 ENTRY(machine_check) + ASM_CLAC pushq $0 movl $TRAP_machine_check,4(%rsp) jmp handle_ist_exception @@ -689,6 +714,7 @@ ENTRY(enable_nmis) /* No op trap handler. Required for kexec crash path. */ GLOBAL(trap_nop) + ASM_CLAC iretq diff --git a/xen/include/asm-x86/x86_64/asm_defns.h b/xen/include/asm-x86/x86_64/asm_defns.h index bf63ac1..69f76b2 100644 --- a/xen/include/asm-x86/x86_64/asm_defns.h +++ b/xen/include/asm-x86/x86_64/asm_defns.h @@ -212,6 +212,7 @@ __asm__( \ "\n" __ALIGN_STR"\n" \ "common_interrupt:\n\t" \ + ASM_CLAC(%)"\n\t" \ STR(SAVE_ALL) "\n\t" \ "movq %rsp,%rdi\n\t" \ "callq " STR(do_IRQ) "\n\t" \ -- 1.8.3.1