diff options
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/alternative-asm.h | 11 | ||||
| -rw-r--r-- | arch/x86/include/asm/alternative.h | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/asm.h | 24 | ||||
| -rw-r--r-- | arch/x86/include/asm/nospec-branch.h | 28 | ||||
| -rw-r--r-- | arch/x86/include/asm/smap.h | 37 | ||||
| -rw-r--r-- | arch/x86/include/asm/switch_to.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/uaccess.h | 12 | ||||
| -rw-r--r-- | arch/x86/include/asm/uaccess_64.h | 3 | ||||
| -rw-r--r-- | arch/x86/include/asm/xen/hypercall.h | 24 |
9 files changed, 87 insertions, 63 deletions
diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h index 31b627b43a8e..464034db299f 100644 --- a/arch/x86/include/asm/alternative-asm.h +++ b/arch/x86/include/asm/alternative-asm.h @@ -20,6 +20,17 @@ #endif /* + * objtool annotation to ignore the alternatives and only consider the original + * instruction(s). + */ +.macro ANNOTATE_IGNORE_ALTERNATIVE + .Lannotate_\@: + .pushsection .discard.ignore_alts + .long .Lannotate_\@ - . + .popsection +.endm + +/* * Issue one struct alt_instr descriptor entry (need to put it into * the section .altinstructions, see below). This entry contains * enough information for the alternatives patching code to patch an diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 4c74073a19cc..094fbc9c0b1c 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -45,6 +45,16 @@ #define LOCK_PREFIX "" #endif +/* + * objtool annotation to ignore the alternatives and only consider the original + * instruction(s). + */ +#define ANNOTATE_IGNORE_ALTERNATIVE \ + "999:\n\t" \ + ".pushsection .discard.ignore_alts\n\t" \ + ".long 999b - .\n\t" \ + ".popsection\n\t" + struct alt_instr { s32 instr_offset; /* original instruction */ s32 repl_offset; /* offset to replacement instruction */ diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 6467757bb39f..3ff577c0b102 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -148,30 +148,6 @@ _ASM_PTR (entry); \ .popsection -.macro ALIGN_DESTINATION - /* check for bad alignment of destination */ - movl %edi,%ecx - andl $7,%ecx - jz 102f /* already aligned */ - subl $8,%ecx - negl %ecx - subl %ecx,%edx -100: movb (%rsi),%al -101: movb %al,(%rdi) - incq %rsi - incq %rdi - decl %ecx - jnz 100b -102: - .section .fixup,"ax" -103: addl %ecx,%edx /* ecx is zerorest also */ - jmp copy_user_handle_tail - .previous - - _ASM_EXTABLE_UA(100b, 103b) - _ASM_EXTABLE_UA(101b, 103b) - .endm - #else # define _EXPAND_EXTABLE_HANDLE(x) #x # define _ASM_EXTABLE_HANDLE(from, to, handler) \ diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index dad12b767ba0..daf25b60c9e3 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -11,6 +11,15 @@ #include <asm/msr-index.h> /* + * This should be used immediately before a retpoline alternative. It tells + * objtool where the retpolines are so that it can make sense of the control + * flow by just reading the original instruction(s) and ignoring the + * alternatives. + */ +#define ANNOTATE_NOSPEC_ALTERNATIVE \ + ANNOTATE_IGNORE_ALTERNATIVE + +/* * Fill the CPU return stack buffer. * * Each entry in the RSB, if used for a speculative 'ret', contains an @@ -57,19 +66,6 @@ #ifdef __ASSEMBLY__ /* - * This should be used immediately before a retpoline alternative. It tells - * objtool where the retpolines are so that it can make sense of the control - * flow by just reading the original instruction(s) and ignoring the - * alternatives. - */ -.macro ANNOTATE_NOSPEC_ALTERNATIVE - .Lannotate_\@: - .pushsection .discard.nospec - .long .Lannotate_\@ - . - .popsection -.endm - -/* * This should be used immediately before an indirect jump/call. It tells * objtool the subsequent indirect jump/call is vouched safe for retpoline * builds. @@ -152,12 +148,6 @@ #else /* __ASSEMBLY__ */ -#define ANNOTATE_NOSPEC_ALTERNATIVE \ - "999:\n\t" \ - ".pushsection .discard.nospec\n\t" \ - ".long 999b - .\n\t" \ - ".popsection\n\t" - #define ANNOTATE_RETPOLINE_SAFE \ "999:\n\t" \ ".pushsection .discard.retpoline_safe\n\t" \ diff --git a/arch/x86/include/asm/smap.h b/arch/x86/include/asm/smap.h index db333300bd4b..f94a7d0ddd49 100644 --- a/arch/x86/include/asm/smap.h +++ b/arch/x86/include/asm/smap.h @@ -13,13 +13,12 @@ #ifndef _ASM_X86_SMAP_H #define _ASM_X86_SMAP_H -#include <linux/stringify.h> #include <asm/nops.h> #include <asm/cpufeatures.h> /* "Raw" instruction opcodes */ -#define __ASM_CLAC .byte 0x0f,0x01,0xca -#define __ASM_STAC .byte 0x0f,0x01,0xcb +#define __ASM_CLAC ".byte 0x0f,0x01,0xca" +#define __ASM_STAC ".byte 0x0f,0x01,0xcb" #ifdef __ASSEMBLY__ @@ -28,10 +27,10 @@ #ifdef CONFIG_X86_SMAP #define ASM_CLAC \ - ALTERNATIVE "", __stringify(__ASM_CLAC), X86_FEATURE_SMAP + ALTERNATIVE "", __ASM_CLAC, X86_FEATURE_SMAP #define ASM_STAC \ - ALTERNATIVE "", __stringify(__ASM_STAC), X86_FEATURE_SMAP + ALTERNATIVE "", __ASM_STAC, X86_FEATURE_SMAP #else /* CONFIG_X86_SMAP */ @@ -49,26 +48,46 @@ static __always_inline void clac(void) { /* Note: a barrier is implicit in alternative() */ - alternative("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP); + alternative("", __ASM_CLAC, X86_FEATURE_SMAP); } static __always_inline void stac(void) { /* Note: a barrier is implicit in alternative() */ - alternative("", __stringify(__ASM_STAC), X86_FEATURE_SMAP); + alternative("", __ASM_STAC, X86_FEATURE_SMAP); +} + +static __always_inline unsigned long smap_save(void) +{ + unsigned long flags; + + asm volatile (ALTERNATIVE("", "pushf; pop %0; " __ASM_CLAC, + X86_FEATURE_SMAP) + : "=rm" (flags) : : "memory", "cc"); + + return flags; +} + +static __always_inline void smap_restore(unsigned long flags) +{ + asm volatile (ALTERNATIVE("", "push %0; popf", X86_FEATURE_SMAP) + : : "g" (flags) : "memory", "cc"); } /* These macros can be used in asm() statements */ #define ASM_CLAC \ - ALTERNATIVE("", __stringify(__ASM_CLAC), X86_FEATURE_SMAP) + ALTERNATIVE("", __ASM_CLAC, X86_FEATURE_SMAP) #define ASM_STAC \ - ALTERNATIVE("", __stringify(__ASM_STAC), X86_FEATURE_SMAP) + ALTERNATIVE("", __ASM_STAC, X86_FEATURE_SMAP) #else /* CONFIG_X86_SMAP */ static inline void clac(void) { } static inline void stac(void) { } +static inline unsigned long smap_save(void) { return 0; } +static inline void smap_restore(unsigned long flags) { } + #define ASM_CLAC #define ASM_STAC diff --git a/arch/x86/include/asm/switch_to.h b/arch/x86/include/asm/switch_to.h index 7cf1a270d891..18a4b6890fa8 100644 --- a/arch/x86/include/asm/switch_to.h +++ b/arch/x86/include/asm/switch_to.h @@ -46,6 +46,7 @@ struct inactive_task_frame { unsigned long r13; unsigned long r12; #else + unsigned long flags; unsigned long si; unsigned long di; #endif diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h index 1954dd5552a2..bb21913885a3 100644 --- a/arch/x86/include/asm/uaccess.h +++ b/arch/x86/include/asm/uaccess.h @@ -427,10 +427,11 @@ do { \ ({ \ __label__ __pu_label; \ int __pu_err = -EFAULT; \ - __typeof__(*(ptr)) __pu_val; \ - __pu_val = x; \ + __typeof__(*(ptr)) __pu_val = (x); \ + __typeof__(ptr) __pu_ptr = (ptr); \ + __typeof__(size) __pu_size = (size); \ __uaccess_begin(); \ - __put_user_size(__pu_val, (ptr), (size), __pu_label); \ + __put_user_size(__pu_val, __pu_ptr, __pu_size, __pu_label); \ __pu_err = 0; \ __pu_label: \ __uaccess_end(); \ @@ -705,7 +706,7 @@ extern struct movsl_mask { * checking before using them, but you have to surround them with the * user_access_begin/end() pair. */ -static __must_check inline bool user_access_begin(const void __user *ptr, size_t len) +static __must_check __always_inline bool user_access_begin(const void __user *ptr, size_t len) { if (unlikely(!access_ok(ptr,len))) return 0; @@ -715,6 +716,9 @@ static __must_check inline bool user_access_begin(const void __user *ptr, size_t #define user_access_begin(a,b) user_access_begin(a,b) #define user_access_end() __uaccess_end() +#define user_access_save() smap_save() +#define user_access_restore(x) smap_restore(x) + #define unsafe_put_user(x, ptr, label) \ __put_user_size((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), label) diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index a9d637bc301d..5cd1caa8bc65 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -208,9 +208,6 @@ __copy_from_user_flushcache(void *dst, const void __user *src, unsigned size) } unsigned long -copy_user_handle_tail(char *to, char *from, unsigned len); - -unsigned long mcsafe_handle_tail(char *to, char *from, unsigned len); #endif /* _ASM_X86_UACCESS_64_H */ diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h index 2863c2026655..d50c7b747d8b 100644 --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -217,6 +217,22 @@ xen_single_call(unsigned int call, return (long)__res; } +static __always_inline void __xen_stac(void) +{ + /* + * Suppress objtool seeing the STAC/CLAC and getting confused about it + * calling random code with AC=1. + */ + asm volatile(ANNOTATE_IGNORE_ALTERNATIVE + ASM_STAC ::: "memory", "flags"); +} + +static __always_inline void __xen_clac(void) +{ + asm volatile(ANNOTATE_IGNORE_ALTERNATIVE + ASM_CLAC ::: "memory", "flags"); +} + static inline long privcmd_call(unsigned int call, unsigned long a1, unsigned long a2, @@ -225,9 +241,9 @@ privcmd_call(unsigned int call, { long res; - stac(); + __xen_stac(); res = xen_single_call(call, a1, a2, a3, a4, a5); - clac(); + __xen_clac(); return res; } @@ -424,9 +440,9 @@ HYPERVISOR_dm_op( domid_t dom, unsigned int nr_bufs, struct xen_dm_op_buf *bufs) { int ret; - stac(); + __xen_stac(); ret = _hypercall3(int, dm_op, dom, nr_bufs, bufs); - clac(); + __xen_clac(); return ret; } |