diff options
-rw-r--r-- | arch/x86/entry/entry_32.S | 13 | ||||
-rw-r--r-- | arch/x86/include/asm/extable_fixup_types.h | 11 | ||||
-rw-r--r-- | arch/x86/lib/insn-eval.c | 5 | ||||
-rw-r--r-- | arch/x86/mm/extable.c | 17 |
4 files changed, 27 insertions, 19 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index e0a95d8a6553..a7ec22b1d06c 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -268,11 +268,16 @@ 1: popl %ds 2: popl %es 3: popl %fs - addl $(4 + \pop), %esp /* pop the unused "gs" slot */ +4: addl $(4 + \pop), %esp /* pop the unused "gs" slot */ IRET_FRAME - _ASM_EXTABLE_TYPE(1b, 1b, EX_TYPE_POP_ZERO) - _ASM_EXTABLE_TYPE(2b, 2b, EX_TYPE_POP_ZERO) - _ASM_EXTABLE_TYPE(3b, 3b, EX_TYPE_POP_ZERO) + + /* + * There is no _ASM_EXTABLE_TYPE_REG() for ASM, however since this is + * ASM the registers are known and we can trivially hard-code them. + */ + _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_POP_ZERO|EX_REG_DS) + _ASM_EXTABLE_TYPE(2b, 3b, EX_TYPE_POP_ZERO|EX_REG_ES) + _ASM_EXTABLE_TYPE(3b, 4b, EX_TYPE_POP_ZERO|EX_REG_FS) .endm .macro RESTORE_ALL_NMI cr3_reg:req pop=0 diff --git a/arch/x86/include/asm/extable_fixup_types.h b/arch/x86/include/asm/extable_fixup_types.h index b5ab333e064a..503622627400 100644 --- a/arch/x86/include/asm/extable_fixup_types.h +++ b/arch/x86/include/asm/extable_fixup_types.h @@ -16,9 +16,16 @@ #define EX_DATA_FLAG_SHIFT 12 #define EX_DATA_IMM_SHIFT 16 +#define EX_DATA_REG(reg) ((reg) << EX_DATA_REG_SHIFT) #define EX_DATA_FLAG(flag) ((flag) << EX_DATA_FLAG_SHIFT) #define EX_DATA_IMM(imm) ((imm) << EX_DATA_IMM_SHIFT) +/* segment regs */ +#define EX_REG_DS EX_DATA_REG(8) +#define EX_REG_ES EX_DATA_REG(9) +#define EX_REG_FS EX_DATA_REG(10) +#define EX_REG_GS EX_DATA_REG(11) + /* flags */ #define EX_FLAG_CLEAR_AX EX_DATA_FLAG(1) #define EX_FLAG_CLEAR_DX EX_DATA_FLAG(2) @@ -41,7 +48,9 @@ #define EX_TYPE_RDMSR_IN_MCE 13 #define EX_TYPE_DEFAULT_MCE_SAFE 14 #define EX_TYPE_FAULT_MCE_SAFE 15 -#define EX_TYPE_POP_ZERO 16 + +#define EX_TYPE_POP_REG 16 /* sp += sizeof(long) */ +#define EX_TYPE_POP_ZERO (EX_TYPE_POP_REG | EX_DATA_IMM(0)) #define EX_TYPE_IMM_REG 17 /* reg := (long)imm */ #define EX_TYPE_EFAULT_REG (EX_TYPE_IMM_REG | EX_DATA_IMM(-EFAULT)) diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index 7760d228041b..c8a962c2e653 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -430,6 +430,11 @@ static const int pt_regoff[] = { offsetof(struct pt_regs, r13), offsetof(struct pt_regs, r14), offsetof(struct pt_regs, r15), +#else + offsetof(struct pt_regs, ds), + offsetof(struct pt_regs, es), + offsetof(struct pt_regs, fs), + offsetof(struct pt_regs, gs), #endif }; diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c index 41eaa648349e..dba2197c05c3 100644 --- a/arch/x86/mm/extable.c +++ b/arch/x86/mm/extable.c @@ -126,18 +126,6 @@ static bool ex_handler_clear_fs(const struct exception_table_entry *fixup, return ex_handler_default(fixup, regs); } -static bool ex_handler_pop_zero(const struct exception_table_entry *fixup, - struct pt_regs *regs) -{ - /* - * Typically used for when "pop %seg" traps, in which case we'll clear - * the stack slot and re-try the instruction, which will then succeed - * to pop zero. - */ - *((unsigned long *)regs->sp) = 0; - return ex_handler_default(fixup, regs); -} - static bool ex_handler_imm_reg(const struct exception_table_entry *fixup, struct pt_regs *regs, int reg, int imm) { @@ -218,8 +206,9 @@ int fixup_exception(struct pt_regs *regs, int trapnr, unsigned long error_code, case EX_TYPE_RDMSR_IN_MCE: ex_handler_msr_mce(regs, false); break; - case EX_TYPE_POP_ZERO: - return ex_handler_pop_zero(e, regs); + case EX_TYPE_POP_REG: + regs->sp += sizeof(long); + fallthrough; case EX_TYPE_IMM_REG: return ex_handler_imm_reg(e, regs, reg, imm); case EX_TYPE_FAULT_SGX: |