target-i386: fix kernel accesses with SMAP and CPL = 3

With SMAP, implicit kernel accesses from user mode always behave as
if AC=0.  To do this, kernel mode is not anymore a separate MMU mode.
Instead, KERNEL_IDX is renamed to KSMAP_IDX and the kernel mode accessors
wrap KSMAP_IDX and KNOSMAP_IDX.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2014-03-28 11:43:45 +01:00
parent 81cf8d8adc
commit 8a201bd47e
3 changed files with 33 additions and 8 deletions

View File

@ -1153,17 +1153,24 @@ static inline CPUX86State *cpu_init(const char *cpu_model)
#define cpudef_setup x86_cpudef_setup #define cpudef_setup x86_cpudef_setup
/* MMU modes definitions */ /* MMU modes definitions */
#define MMU_MODE0_SUFFIX _kernel #define MMU_MODE0_SUFFIX _ksmap
#define MMU_MODE1_SUFFIX _user #define MMU_MODE1_SUFFIX _user
#define MMU_MODE2_SUFFIX _knosmap /* SMAP disabled or CPL<3 && AC=1 */ #define MMU_MODE2_SUFFIX _knosmap /* SMAP disabled or CPL<3 && AC=1 */
#define MMU_KERNEL_IDX 0 #define MMU_KSMAP_IDX 0
#define MMU_USER_IDX 1 #define MMU_USER_IDX 1
#define MMU_KNOSMAP_IDX 2 #define MMU_KNOSMAP_IDX 2
static inline int cpu_mmu_index (CPUX86State *env) static inline int cpu_mmu_index(CPUX86State *env)
{ {
return (env->hflags & HF_CPL_MASK) == 3 ? MMU_USER_IDX : return (env->hflags & HF_CPL_MASK) == 3 ? MMU_USER_IDX :
((env->hflags & HF_SMAP_MASK) && (env->eflags & AC_MASK)) ((env->hflags & HF_SMAP_MASK) && (env->eflags & AC_MASK))
? MMU_KNOSMAP_IDX : MMU_KERNEL_IDX; ? MMU_KNOSMAP_IDX : MMU_KSMAP_IDX;
}
static inline int cpu_mmu_index_kernel(CPUX86State *env)
{
return !(env->hflags & HF_SMAP_MASK) ? MMU_KNOSMAP_IDX :
((env->hflags & HF_CPL_MASK) < 3 && (env->eflags & AC_MASK))
? MMU_KNOSMAP_IDX : MMU_KSMAP_IDX;
} }
#define CC_DST (env->cc_dst) #define CC_DST (env->cc_dst)

View File

@ -648,7 +648,7 @@ int x86_cpu_handle_mmu_fault(CPUState *cs, vaddr addr,
} }
break; break;
case MMU_KERNEL_IDX: case MMU_KSMAP_IDX:
if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) && if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) &&
(ptep & PG_USER_MASK)) { (ptep & PG_USER_MASK)) {
goto do_fault_protect; goto do_fault_protect;
@ -710,7 +710,7 @@ int x86_cpu_handle_mmu_fault(CPUState *cs, vaddr addr,
} }
break; break;
case MMU_KERNEL_IDX: case MMU_KSMAP_IDX:
if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) && if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) &&
(ptep & PG_USER_MASK)) { (ptep & PG_USER_MASK)) {
goto do_fault_protect; goto do_fault_protect;
@ -765,7 +765,7 @@ int x86_cpu_handle_mmu_fault(CPUState *cs, vaddr addr,
} }
break; break;
case MMU_KERNEL_IDX: case MMU_KSMAP_IDX:
if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) && if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) &&
(pde & PG_USER_MASK)) { (pde & PG_USER_MASK)) {
goto do_fault_protect; goto do_fault_protect;
@ -822,7 +822,7 @@ int x86_cpu_handle_mmu_fault(CPUState *cs, vaddr addr,
} }
break; break;
case MMU_KERNEL_IDX: case MMU_KSMAP_IDX:
if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) && if (is_write1 != 2 && (env->cr[4] & CR4_SMAP_MASK) &&
(ptep & PG_USER_MASK)) { (ptep & PG_USER_MASK)) {
goto do_fault_protect; goto do_fault_protect;

View File

@ -34,6 +34,24 @@
# define LOG_PCALL_STATE(cpu) do { } while (0) # define LOG_PCALL_STATE(cpu) do { } while (0)
#endif #endif
#ifndef CONFIG_USER_ONLY
#define CPU_MMU_INDEX (cpu_mmu_index_kernel(env))
#define MEMSUFFIX _kernel
#define DATA_SIZE 1
#include "exec/cpu_ldst_template.h"
#define DATA_SIZE 2
#include "exec/cpu_ldst_template.h"
#define DATA_SIZE 4
#include "exec/cpu_ldst_template.h"
#define DATA_SIZE 8
#include "exec/cpu_ldst_template.h"
#undef CPU_MMU_INDEX
#undef MEMSUFFIX
#endif
/* return non zero if error */ /* return non zero if error */
static inline int load_segment(CPUX86State *env, uint32_t *e1_ptr, static inline int load_segment(CPUX86State *env, uint32_t *e1_ptr,
uint32_t *e2_ptr, int selector) uint32_t *e2_ptr, int selector)