microblaze: Emulate the hw stackprotector

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
This commit is contained in:
Edgar E. Iglesias 2012-01-10 10:27:11 +01:00
parent 48b5e96f0f
commit 5818dee572
4 changed files with 48 additions and 0 deletions

View file

@ -93,6 +93,7 @@ struct CPUMBState;
#define ESR_EC_DIVZERO 5
#define ESR_EC_FPU 6
#define ESR_EC_PRIVINSN 7
#define ESR_EC_STACKPROT 7 /* Same as PRIVINSN. */
#define ESR_EC_DATA_STORAGE 8
#define ESR_EC_INSN_STORAGE 9
#define ESR_EC_DATA_TLB 10
@ -235,6 +236,8 @@ typedef struct CPUMBState {
uint32_t regs[33];
uint32_t sregs[24];
float_status fp_status;
/* Stack protectors. Yes, it's a hw feature. */
uint32_t slr, shr;
/* Internal flags. */
#define IMM_FLAG 4

View file

@ -33,6 +33,7 @@ DEF_HELPER_2(mmu_write, void, i32, i32)
#endif
DEF_HELPER_4(memalign, void, i32, i32, i32, i32)
DEF_HELPER_1(stackprot, void, i32)
DEF_HELPER_2(get, i32, i32, i32)
DEF_HELPER_3(put, void, i32, i32, i32)

View file

@ -483,6 +483,17 @@ void helper_memalign(uint32_t addr, uint32_t dr, uint32_t wr, uint32_t mask)
}
}
void helper_stackprot(uint32_t addr)
{
if (addr < env->slr || addr > env->shr) {
qemu_log("Stack protector violation at %x %x %x\n",
addr, env->slr, env->shr);
env->sregs[SR_EAR] = addr;
env->sregs[SR_ESR] = ESR_EC_STACKPROT;
helper_raise_exception(EXCP_HW_EXCP);
}
}
#if !defined(CONFIG_USER_ONLY)
/* Writes/reads to the MMU's special regs end up here. */
uint32_t helper_mmu_read(uint32_t rn)

View file

@ -526,6 +526,12 @@ static void dec_msr(DisasContext *dc)
case 0x7:
tcg_gen_andi_tl(cpu_SR[SR_FSR], cpu_R[dc->ra], 31);
break;
case 0x800:
tcg_gen_st_tl(cpu_R[dc->ra], cpu_env, offsetof(CPUState, slr));
break;
case 0x802:
tcg_gen_st_tl(cpu_R[dc->ra], cpu_env, offsetof(CPUState, shr));
break;
default:
cpu_abort(dc->env, "unknown mts reg %x\n", sr);
break;
@ -552,6 +558,12 @@ static void dec_msr(DisasContext *dc)
case 0xb:
tcg_gen_mov_tl(cpu_R[dc->rd], cpu_SR[SR_BTR]);
break;
case 0x800:
tcg_gen_ld_tl(cpu_R[dc->rd], cpu_env, offsetof(CPUState, slr));
break;
case 0x802:
tcg_gen_ld_tl(cpu_R[dc->rd], cpu_env, offsetof(CPUState, shr));
break;
case 0x2000:
case 0x2001:
case 0x2002:
@ -864,6 +876,13 @@ static inline void gen_load(DisasContext *dc, TCGv dst, TCGv addr,
static inline TCGv *compute_ldst_addr(DisasContext *dc, TCGv *t)
{
unsigned int extimm = dc->tb_flags & IMM_FLAG;
/* Should be set to one if r1 is used by loadstores. */
int stackprot = 0;
/* All load/stores use ra. */
if (dc->ra == 1) {
stackprot = 1;
}
/* Treat the common cases first. */
if (!dc->type_b) {
@ -874,8 +893,16 @@ static inline TCGv *compute_ldst_addr(DisasContext *dc, TCGv *t)
return &cpu_R[dc->ra];
}
if (dc->rb == 1) {
stackprot = 1;
}
*t = tcg_temp_new();
tcg_gen_add_tl(*t, cpu_R[dc->ra], cpu_R[dc->rb]);
if (stackprot) {
gen_helper_stackprot(*t);
}
return t;
}
/* Immediate. */
@ -891,6 +918,9 @@ static inline TCGv *compute_ldst_addr(DisasContext *dc, TCGv *t)
tcg_gen_add_tl(*t, cpu_R[dc->ra], *(dec_alu_op_b(dc)));
}
if (stackprot) {
gen_helper_stackprot(*t);
}
return t;
}
@ -1917,6 +1947,9 @@ void cpu_reset (CPUState *env)
memset(env, 0, offsetof(CPUMBState, breakpoints));
tlb_flush(env, 1);
/* Disable stack protector. */
env->shr = ~0;
env->pvr.regs[0] = PVR0_PVR_FULL_MASK \
| PVR0_USE_BARREL_MASK \
| PVR0_USE_DIV_MASK \