case 4:
ctxt->_eip = (u32)dst;
break;
+#ifdef CONFIG_X86_64
case 8:
if ((cs_l && is_noncanonical_address(dst)) ||
- (!cs_l && (dst & ~(u32)-1)))
+ (!cs_l && (dst >> 32) != 0))
return emulate_gp(ctxt, 0);
ctxt->_eip = dst;
break;
+#endif
default:
WARN(1, "unsupported eip assignment size\n");
}
/* Does not support long mode */
static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
- u16 selector, int seg, u8 cpl)
+ u16 selector, int seg, u8 cpl,
+ struct desc_struct *desc)
{
struct desc_struct seg_desc;
u8 dpl, rpl;
}
load:
ctxt->ops->set_segment(ctxt, selector, &seg_desc, 0, seg);
+ if (desc)
+ *desc = seg_desc;
return X86EMUL_CONTINUE;
exception:
emulate_exception(ctxt, err_vec, err_code, true);
u16 selector, int seg)
{
u8 cpl = ctxt->ops->cpl(ctxt);
- return __load_segment_descriptor(ctxt, selector, seg, cpl);
+ return __load_segment_descriptor(ctxt, selector, seg, cpl, NULL);
}
static void write_register_operand(struct operand *op)
static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
{
int rc;
- unsigned short sel;
+ unsigned short sel, old_sel;
+ struct desc_struct old_desc, new_desc;
+ const struct x86_emulate_ops *ops = ctxt->ops;
+ u8 cpl = ctxt->ops->cpl(ctxt);
+
+ /* Assignment of RIP may only fail in 64-bit mode */
+ if (ctxt->mode == X86EMUL_MODE_PROT64)
+ ops->get_segment(ctxt, &old_sel, &old_desc, NULL,
+ VCPU_SREG_CS);
memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
- rc = load_segment_descriptor(ctxt, sel, VCPU_SREG_CS);
+ rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl,
+ &new_desc);
if (rc != X86EMUL_CONTINUE)
return rc;
- ctxt->_eip = 0;
- memcpy(&ctxt->_eip, ctxt->src.valptr, ctxt->op_bytes);
- return X86EMUL_CONTINUE;
+ rc = assign_eip_far(ctxt, ctxt->src.val, new_desc.l);
+ if (rc != X86EMUL_CONTINUE) {
+ WARN_ON(ctxt->mode != X86EMUL_MODE_PROT64);
+ /* assigning eip failed; restore the old cs */
+ ops->set_segment(ctxt, old_sel, &old_desc, 0, VCPU_SREG_CS);
+ return rc;
+ }
+ return rc;
}
static int em_grp1a(struct x86_emulate_ctxt *ctxt)
static int em_ret_far(struct x86_emulate_ctxt *ctxt)
{
int rc;
- unsigned long cs;
+ unsigned long eip, cs;
+ u16 old_cs;
int cpl = ctxt->ops->cpl(ctxt);
+ struct desc_struct old_desc, new_desc;
+ const struct x86_emulate_ops *ops = ctxt->ops;
- rc = emulate_pop(ctxt, &ctxt->_eip, ctxt->op_bytes);
+ if (ctxt->mode == X86EMUL_MODE_PROT64)
+ ops->get_segment(ctxt, &old_cs, &old_desc, NULL,
+ VCPU_SREG_CS);
+
+ rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
if (rc != X86EMUL_CONTINUE)
return rc;
- if (ctxt->op_bytes == 4)
- ctxt->_eip = (u32)ctxt->_eip;
rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
if (rc != X86EMUL_CONTINUE)
return rc;
/* Outer-privilege level return is not implemented */
if (ctxt->mode >= X86EMUL_MODE_PROT16 && (cs & 3) > cpl)
return X86EMUL_UNHANDLEABLE;
- rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS);
+ rc = __load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS, 0,
+ &new_desc);
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
+ rc = assign_eip_far(ctxt, eip, new_desc.l);
+ if (rc != X86EMUL_CONTINUE) {
+ WARN_ON(ctxt->mode != X86EMUL_MODE_PROT64);
+ ops->set_segment(ctxt, old_cs, &old_desc, 0, VCPU_SREG_CS);
+ }
return rc;
}
ss->p = 1;
}
+static bool vendor_intel(struct x86_emulate_ctxt *ctxt)
+{
+ u32 eax, ebx, ecx, edx;
+
+ eax = ecx = 0;
+ return ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx)
+ && ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx
+ && ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx
+ && edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx;
+}
+
static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
{
struct x86_emulate_ops *ops = ctxt->ops;
if (ctxt->mode == X86EMUL_MODE_REAL)
return emulate_gp(ctxt, 0);
+ /*
+ * Not recognized on AMD in compat mode (but is recognized in legacy
+ * mode).
+ */
+ if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA)
+ && !vendor_intel(ctxt))
+ return emulate_ud(ctxt);
+
/* XXX sysenter/sysexit have not been tested in 64bit mode.
* Therefore, we inject an #UD.
*/
setup_syscalls_segments(ctxt, &cs, &ss);
ops->get_msr(ctxt, MSR_IA32_SYSENTER_CS, &msr_data);
- switch (ctxt->mode) {
- case X86EMUL_MODE_PROT32:
- if ((msr_data & 0xfffc) == 0x0)
- return emulate_gp(ctxt, 0);
- break;
- case X86EMUL_MODE_PROT64:
- if (msr_data == 0x0)
- return emulate_gp(ctxt, 0);
- break;
- }
+ if ((msr_data & 0xfffc) == 0x0)
+ return emulate_gp(ctxt, 0);
ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
- cs_sel = (u16)msr_data;
- cs_sel &= ~SELECTOR_RPL_MASK;
+ cs_sel = (u16)msr_data & ~SELECTOR_RPL_MASK;
ss_sel = cs_sel + 8;
- ss_sel &= ~SELECTOR_RPL_MASK;
- if (ctxt->mode == X86EMUL_MODE_PROT64 || (efer & EFER_LMA)) {
+ if (efer & EFER_LMA) {
cs.d = 0;
cs.l = 1;
}
ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
ops->get_msr(ctxt, MSR_IA32_SYSENTER_EIP, &msr_data);
- ctxt->_eip = msr_data;
+ ctxt->_eip = (efer & EFER_LMA) ? msr_data : (u32)msr_data;
ops->get_msr(ctxt, MSR_IA32_SYSENTER_ESP, &msr_data);
- ctxt->regs[VCPU_REGS_RSP] = msr_data;
+ ctxt->regs[VCPU_REGS_RSP] = (efer & EFER_LMA) ? msr_data :
+ (u32)msr_data;
return X86EMUL_CONTINUE;
}
* Now load segment descriptors. If fault happenes at this stage
* it is handled in a context of new task
*/
- ret = __load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
* Now load segment descriptors. If fault happenes at this stage
* it is handled in a context of new task
*/
- ret = __load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR,
+ cpl, NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
- ret = __load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS, cpl);
+ ret = __load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS, cpl,
+ NULL);
if (ret != X86EMUL_CONTINUE)
return ret;
u16 sel, old_cs;
ulong old_eip;
int rc;
+ struct desc_struct old_desc, new_desc;
+ const struct x86_emulate_ops *ops = ctxt->ops;
+ int cpl = ctxt->ops->cpl(ctxt);
- old_cs = get_segment_selector(ctxt, VCPU_SREG_CS);
old_eip = ctxt->_eip;
+ ops->get_segment(ctxt, &old_cs, &old_desc, NULL, VCPU_SREG_CS);
memcpy(&sel, ctxt->src.valptr + ctxt->op_bytes, 2);
- if (load_segment_descriptor(ctxt, sel, VCPU_SREG_CS))
+ rc = __load_segment_descriptor(ctxt, sel, VCPU_SREG_CS, cpl,
+ &new_desc);
+ if (rc != X86EMUL_CONTINUE)
return X86EMUL_CONTINUE;
- ctxt->_eip = 0;
- memcpy(&ctxt->_eip, ctxt->src.valptr, ctxt->op_bytes);
+ rc = assign_eip_far(ctxt, ctxt->src.val, new_desc.l);
+ if (rc != X86EMUL_CONTINUE)
+ goto fail;
ctxt->src.val = old_cs;
rc = em_push(ctxt);
if (rc != X86EMUL_CONTINUE)
- return rc;
+ goto fail;
ctxt->src.val = old_eip;
- return em_push(ctxt);
+ rc = em_push(ctxt);
+ /* If we failed, we tainted the memory, but the very least we should
+ restore cs */
+ if (rc != X86EMUL_CONTINUE)
+ goto fail;
+ return rc;
+fail:
+ ops->set_segment(ctxt, old_cs, &old_desc, 0, VCPU_SREG_CS);
+ return rc;
+
}
static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)