/*
* Copyright (c) 2015, Google Inc. All rights reserved
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <asm.h>
#include <arch/asm_macros.h>
#include <err.h>
/**
* int mmutest_arch_rodata_pnx(void) - Test that rodata section is mapped pnx
*
* Returns ERR_FAULT if rodata is not executable.
* Return 0 if rodata is executable.
*/
.
section .rodata
set_fault_handler .Lmmutest_fault
FUNCTION(mmutest_arch_rodata_pnx)
xor %eax, %eax
ret
/**
* int mmutest_arch_data_pnx(void) - Test that data section is mapped pnx
*
* Returns ERR_FAULT if data is not executable.
* Return 0 if data is executable.
*/
.
section .
data
set_fault_handler .Lmmutest_fault
FUNCTION(mmutest_arch_data_pnx)
xor %eax, %eax
ret
.
section .text
/**
* int mmutest_arch_rodata_ro(void) - Test that rodata section is mapped read-only
*
* Returns ERR_FAULT if rodata is not writable
* Returns 1 if write to rodata is silently dropped
* Returns 0 if rodata is writable
*/
FUNCTION(mmutest_arch_rodata_ro)
leaq .Ltest_rodata_long(%rip), %rax
set_fault_handler .Lmmutest_fault
movl $
0, (%rax)
movl (%rax), %eax
ret
.
section .rodata
.balign
4
.Ltest_rodata_long:
.long
0x1
.
section .text
/**
* int mmutest_arch_store_uint32(uint32_t *ptr, bool user) - Test if ptr is writable
* @ptr: Memory location to test
* @user: Use unprivileged store
*
* Returns ERR_FAULT if ptr is not writable
* Returns ERR_GENERIC if ptr is not readable
* Returns 2 if write does not fault, but data is lost on readback from memory
* Returns 1 if write does not fault, but data is lost on readback from cache
* Returns 0 if ptr is writable
*/
FUNCTION(mmutest_arch_store_uint32)
test %sil, %sil
jnz .Lmmutest_arch_store_uint32_user
set_fault_handler .Lmmutest_setup_fault
movl (%rdi), %edx
not %edx
set_fault_handler .Lmmutest_fault
movl %edx, (%rdi)
mfence
movl (%rdi), %ecx
jmp .Lmmutest_arch_store_uint32_str_done
.Lmmutest_arch_store_uint32_user:
/* TODO: call helper functions to write then read from user-space */
movl $ERR_NOT_IMPLEMENTED, %eax
ret
.Lmmutest_arch_store_uint32_str_done:
cmp %edx, %ecx
jne .Lmmutest_arch_store_uint32_cache_read_mismatch
push %rdi
push %rsi
push %rdx
movq $
4, %rsi
call arch_clean_invalidate_cache_range
pop %rdx
pop %rsi
pop %rdi
test %sil, %sil
jnz .Lmmutest_arch_store_uint32_memory_reload_user
movl (%rdi), %ecx
jmp .Lmmutest_arch_store_uint32_memory_reload_done
.Lmmutest_arch_store_uint32_memory_reload_user:
/* TODO: call helper function to read from user-space */
.Lmmutest_arch_store_uint32_memory_reload_done:
cmp %edx, %ecx
jne .Lmmutest_arch_store_uint32_memory_mismatch
xor %eax, %eax
ret
.Lmmutest_arch_store_uint32_cache_read_mismatch:
movl $
1, %eax
ret
.Lmmutest_arch_store_uint32_memory_mismatch:
movl $
2, %eax
ret
/**
* int mmutest_arch_nop(int ret) - Return ret
*
* Returns ret if run from executable page.
* Does not return if run from non-executable page.
*/
FUNCTION(mmutest_arch_nop)
ret
FUNCTION(mmutest_arch_nop_end)
.Lmmutest_setup_fault:
movl $ERR_GENERIC, %eax
ret
.Lmmutest_fault:
movl $ERR_FAULT, %eax
ret
