diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c index 6ba82be68cff..1f1f2d54dab5 100644 --- a/arch/x86/kernel/umip.c +++ b/arch/x86/kernel/umip.c @@ -78,7 +78,9 @@ #define UMIP_INST_SGDT 0 /* 0F 01 /0 */ #define UMIP_INST_SIDT 1 /* 0F 01 /1 */ -#define UMIP_INST_SMSW 3 /* 0F 01 /4 */ +#define UMIP_INST_SMSW 2 /* 0F 01 /4 */ +#define UMIP_INST_SLDT 3 /* 0F 00 /0 */ +#define UMIP_INST_STR 4 /* 0F 00 /1 */ /** * identify_insn() - Identify a UMIP-protected instruction @@ -118,10 +120,16 @@ static int identify_insn(struct insn *insn) default: return -EINVAL; } + } else if (insn->opcode.bytes[1] == 0x0) { + if (X86_MODRM_REG(insn->modrm.value) == 0) + return UMIP_INST_SLDT; + else if (X86_MODRM_REG(insn->modrm.value) == 1) + return UMIP_INST_STR; + else + return -EINVAL; + } else { + return -EINVAL; } - - /* SLDT AND STR are not emulated */ - return -EINVAL; } /** @@ -267,10 +275,6 @@ bool fixup_umip_exception(struct pt_regs *regs) if (!regs) return false; - /* Do not emulate 64-bit processes. */ - if (user_64bit_mode(regs)) - return false; - /* * If not in user-space long mode, a custom code segment could be in * use. This is true in protected mode (if the process defined a local @@ -322,6 +326,10 @@ bool fixup_umip_exception(struct pt_regs *regs) if (umip_inst < 0) return false; + /* Do not emulate SLDT, STR or user long mode processes. */ + if (umip_inst == UMIP_INST_STR || umip_inst == UMIP_INST_SLDT || user_64bit_mode(regs)) + return false; + if (emulate_umip_insn(&insn, umip_inst, dummy_data, &dummy_data_size)) return false;