diff options
Diffstat (limited to 'arch/x86/lib/getuser.S')
| -rw-r--r-- | arch/x86/lib/getuser.S | 43 |
1 files changed, 35 insertions, 8 deletions
diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S index 156b9c804670..a4512359656a 100644 --- a/arch/x86/lib/getuser.S +++ b/arch/x86/lib/getuser.S @@ -15,11 +15,10 @@ * __get_user_X * * Inputs: %[r|e]ax contains the address. - * The register is modified, but all changes are undone - * before returning because the C code doesn't know about it. * * Outputs: %[r|e]ax is error code (0 or -EFAULT) * %[r|e]dx contains zero-extended value + * %ecx contains the high half for 32-bit __get_user_8 * * * These functions should not modify any other registers, @@ -42,7 +41,7 @@ ENTRY(__get_user_1) cmp TI_addr_limit(%_ASM_DX),%_ASM_AX jae bad_get_user ASM_STAC -1: movzb (%_ASM_AX),%edx +1: movzbl (%_ASM_AX),%edx xor %eax,%eax ASM_CLAC ret @@ -72,29 +71,42 @@ ENTRY(__get_user_4) cmp TI_addr_limit(%_ASM_DX),%_ASM_AX jae bad_get_user ASM_STAC -3: mov -3(%_ASM_AX),%edx +3: movl -3(%_ASM_AX),%edx xor %eax,%eax ASM_CLAC ret CFI_ENDPROC ENDPROC(__get_user_4) -#ifdef CONFIG_X86_64 ENTRY(__get_user_8) CFI_STARTPROC +#ifdef CONFIG_X86_64 add $7,%_ASM_AX jc bad_get_user GET_THREAD_INFO(%_ASM_DX) cmp TI_addr_limit(%_ASM_DX),%_ASM_AX - jae bad_get_user + jae bad_get_user ASM_STAC -4: movq -7(%_ASM_AX),%_ASM_DX +4: movq -7(%_ASM_AX),%rdx xor %eax,%eax ASM_CLAC ret +#else + add $7,%_ASM_AX + jc bad_get_user_8 + GET_THREAD_INFO(%_ASM_DX) + cmp TI_addr_limit(%_ASM_DX),%_ASM_AX + jae bad_get_user_8 + ASM_STAC +4: movl -7(%_ASM_AX),%edx +5: movl -3(%_ASM_AX),%ecx + xor %eax,%eax + ASM_CLAC + ret +#endif CFI_ENDPROC ENDPROC(__get_user_8) -#endif + bad_get_user: CFI_STARTPROC @@ -105,9 +117,24 @@ bad_get_user: CFI_ENDPROC END(bad_get_user) +#ifdef CONFIG_X86_32 +bad_get_user_8: + CFI_STARTPROC + xor %edx,%edx + xor %ecx,%ecx + mov $(-EFAULT),%_ASM_AX + ASM_CLAC + ret + CFI_ENDPROC +END(bad_get_user_8) +#endif + _ASM_EXTABLE(1b,bad_get_user) _ASM_EXTABLE(2b,bad_get_user) _ASM_EXTABLE(3b,bad_get_user) #ifdef CONFIG_X86_64 _ASM_EXTABLE(4b,bad_get_user) +#else + _ASM_EXTABLE(4b,bad_get_user_8) + _ASM_EXTABLE(5b,bad_get_user_8) #endif |