diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 47 |
1 files changed, 30 insertions, 17 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 1bedd520a752..aa71c95e1c51 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1233,11 +1233,11 @@ static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt, } /* Does not support long mode */ -static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt, - u16 selector, int seg) +static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt, + u16 selector, int seg, u8 cpl) { struct desc_struct seg_desc; - u8 dpl, rpl, cpl; + u8 dpl, rpl; unsigned err_vec = GP_VECTOR; u32 err_code = 0; bool null_selector = !(selector & ~0x3); /* 0000-0003 are null */ @@ -1286,7 +1286,6 @@ static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt, rpl = selector & 3; dpl = seg_desc.dpl; - cpl = ctxt->ops->cpl(ctxt); switch (seg) { case VCPU_SREG_SS: @@ -1349,6 +1348,13 @@ exception: return X86EMUL_PROPAGATE_FAULT; } +static int load_segment_descriptor(struct x86_emulate_ctxt *ctxt, + u16 selector, int seg) +{ + u8 cpl = ctxt->ops->cpl(ctxt); + return __load_segment_descriptor(ctxt, selector, seg, cpl); +} + static void write_register_operand(struct operand *op) { /* The 4-byte case *is* correct: in 64-bit mode we zero-extend. */ @@ -2213,6 +2219,7 @@ static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt, struct tss_segment_16 *tss) { int ret; + u8 cpl; ctxt->_eip = tss->ip; ctxt->eflags = tss->flag | 2; @@ -2235,23 +2242,25 @@ static int load_state_from_tss16(struct x86_emulate_ctxt *ctxt, set_segment_selector(ctxt, tss->ss, VCPU_SREG_SS); set_segment_selector(ctxt, tss->ds, VCPU_SREG_DS); + cpl = tss->cs & 3; + /* * 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); + ret = __load_segment_descriptor(ctxt, tss->ldt, VCPU_SREG_LDTR, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES); + ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS); + ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS); + ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS); + ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl); if (ret != X86EMUL_CONTINUE) return ret; @@ -2330,6 +2339,7 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt, struct tss_segment_32 *tss) { int ret; + u8 cpl; if (ctxt->ops->set_cr(ctxt, 3, tss->cr3)) return emulate_gp(ctxt, 0); @@ -2346,7 +2356,8 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt, /* * SDM says that segment selectors are loaded before segment - * descriptors + * descriptors. This is important because CPL checks will + * use CS.RPL. */ set_segment_selector(ctxt, tss->ldt_selector, VCPU_SREG_LDTR); set_segment_selector(ctxt, tss->es, VCPU_SREG_ES); @@ -2356,29 +2367,31 @@ static int load_state_from_tss32(struct x86_emulate_ctxt *ctxt, set_segment_selector(ctxt, tss->fs, VCPU_SREG_FS); set_segment_selector(ctxt, tss->gs, VCPU_SREG_GS); + cpl = tss->cs & 3; + /* * 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); + ret = __load_segment_descriptor(ctxt, tss->ldt_selector, VCPU_SREG_LDTR, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES); + ret = __load_segment_descriptor(ctxt, tss->es, VCPU_SREG_ES, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS); + ret = __load_segment_descriptor(ctxt, tss->cs, VCPU_SREG_CS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS); + ret = __load_segment_descriptor(ctxt, tss->ss, VCPU_SREG_SS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS); + ret = __load_segment_descriptor(ctxt, tss->ds, VCPU_SREG_DS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS); + ret = __load_segment_descriptor(ctxt, tss->fs, VCPU_SREG_FS, cpl); if (ret != X86EMUL_CONTINUE) return ret; - ret = load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS); + ret = __load_segment_descriptor(ctxt, tss->gs, VCPU_SREG_GS, cpl); if (ret != X86EMUL_CONTINUE) return ret; |