diff options
Diffstat (limited to 'arch/x86/lib')
-rw-r--r-- | arch/x86/lib/copy_user_64.S | 18 | ||||
-rw-r--r-- | arch/x86/lib/retpoline.S | 39 | ||||
-rw-r--r-- | arch/x86/lib/x86-opcode-map.txt | 54 |
3 files changed, 84 insertions, 27 deletions
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S index fc9fb5d06174..b8f74d80f35c 100644 --- a/arch/x86/lib/copy_user_64.S +++ b/arch/x86/lib/copy_user_64.S @@ -74,6 +74,24 @@ SYM_FUNC_START(rep_movs_alternative) _ASM_EXTABLE_UA( 0b, 1b) .Llarge_movsq: + /* Do the first possibly unaligned word */ +0: movq (%rsi),%rax +1: movq %rax,(%rdi) + + _ASM_EXTABLE_UA( 0b, .Lcopy_user_tail) + _ASM_EXTABLE_UA( 1b, .Lcopy_user_tail) + + /* What would be the offset to the aligned destination? */ + leaq 8(%rdi),%rax + andq $-8,%rax + subq %rdi,%rax + + /* .. and update pointers and count to match */ + addq %rax,%rdi + addq %rax,%rsi + subq %rax,%rcx + + /* make %rcx contain the number of words, %rax the remainder */ movq %rcx,%rax shrq $3,%rcx andl $7,%eax diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index 391059b2c6fb..614fb9aee2ff 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -366,6 +366,45 @@ SYM_FUNC_END(call_depth_return_thunk) #endif /* CONFIG_MITIGATION_CALL_DEPTH_TRACKING */ +#ifdef CONFIG_MITIGATION_ITS + +.macro ITS_THUNK reg + +SYM_INNER_LABEL(__x86_indirect_its_thunk_\reg, SYM_L_GLOBAL) + UNWIND_HINT_UNDEFINED + ANNOTATE_NOENDBR + ANNOTATE_RETPOLINE_SAFE + jmp *%\reg + int3 + .align 32, 0xcc /* fill to the end of the line */ + .skip 32, 0xcc /* skip to the next upper half */ +.endm + +/* ITS mitigation requires thunks be aligned to upper half of cacheline */ +.align 64, 0xcc +.skip 32, 0xcc +SYM_CODE_START(__x86_indirect_its_thunk_array) + +#define GEN(reg) ITS_THUNK reg +#include <asm/GEN-for-each-reg.h> +#undef GEN + + .align 64, 0xcc +SYM_CODE_END(__x86_indirect_its_thunk_array) + +.align 64, 0xcc +.skip 32, 0xcc +SYM_CODE_START(its_return_thunk) + UNWIND_HINT_FUNC + ANNOTATE_NOENDBR + ANNOTATE_UNRET_SAFE + ret + int3 +SYM_CODE_END(its_return_thunk) +EXPORT_SYMBOL(its_return_thunk) + +#endif /* CONFIG_MITIGATION_ITS */ + /* * This function name is magical and is used by -mfunction-return=thunk-extern * for the compiler to generate JMPs to it. diff --git a/arch/x86/lib/x86-opcode-map.txt b/arch/x86/lib/x86-opcode-map.txt index caedb3ef6688..cd3fd5155f6e 100644 --- a/arch/x86/lib/x86-opcode-map.txt +++ b/arch/x86/lib/x86-opcode-map.txt @@ -35,7 +35,7 @@ # - (!F3) : the last prefix is not 0xF3 (including non-last prefix case) # - (66&F2): Both 0x66 and 0xF2 prefixes are specified. # -# REX2 Prefix +# REX2 Prefix Superscripts # - (!REX2): REX2 is not allowed # - (REX2): REX2 variant e.g. JMPABS @@ -286,10 +286,10 @@ df: ESC # Note: "forced64" is Intel CPU behavior: they ignore 0x66 prefix # in 64-bit mode. AMD CPUs accept 0x66 prefix, it causes RIP truncation # to 16 bits. In 32-bit mode, 0x66 is accepted by both Intel and AMD. -e0: LOOPNE/LOOPNZ Jb (f64) (!REX2) -e1: LOOPE/LOOPZ Jb (f64) (!REX2) -e2: LOOP Jb (f64) (!REX2) -e3: JrCXZ Jb (f64) (!REX2) +e0: LOOPNE/LOOPNZ Jb (f64),(!REX2) +e1: LOOPE/LOOPZ Jb (f64),(!REX2) +e2: LOOP Jb (f64),(!REX2) +e3: JrCXZ Jb (f64),(!REX2) e4: IN AL,Ib (!REX2) e5: IN eAX,Ib (!REX2) e6: OUT Ib,AL (!REX2) @@ -298,10 +298,10 @@ e7: OUT Ib,eAX (!REX2) # in "near" jumps and calls is 16-bit. For CALL, # push of return address is 16-bit wide, RSP is decremented by 2 # but is not truncated to 16 bits, unlike RIP. -e8: CALL Jz (f64) (!REX2) -e9: JMP-near Jz (f64) (!REX2) -ea: JMP-far Ap (i64) (!REX2) -eb: JMP-short Jb (f64) (!REX2) +e8: CALL Jz (f64),(!REX2) +e9: JMP-near Jz (f64),(!REX2) +ea: JMP-far Ap (i64),(!REX2) +eb: JMP-short Jb (f64),(!REX2) ec: IN AL,DX (!REX2) ed: IN eAX,DX (!REX2) ee: OUT DX,AL (!REX2) @@ -478,22 +478,22 @@ AVXcode: 1 7f: movq Qq,Pq | vmovdqa Wx,Vx (66) | vmovdqa32/64 Wx,Vx (66),(evo) | vmovdqu Wx,Vx (F3) | vmovdqu32/64 Wx,Vx (F3),(evo) | vmovdqu8/16 Wx,Vx (F2),(ev) # 0x0f 0x80-0x8f # Note: "forced64" is Intel CPU behavior (see comment about CALL insn). -80: JO Jz (f64) (!REX2) -81: JNO Jz (f64) (!REX2) -82: JB/JC/JNAE Jz (f64) (!REX2) -83: JAE/JNB/JNC Jz (f64) (!REX2) -84: JE/JZ Jz (f64) (!REX2) -85: JNE/JNZ Jz (f64) (!REX2) -86: JBE/JNA Jz (f64) (!REX2) -87: JA/JNBE Jz (f64) (!REX2) -88: JS Jz (f64) (!REX2) -89: JNS Jz (f64) (!REX2) -8a: JP/JPE Jz (f64) (!REX2) -8b: JNP/JPO Jz (f64) (!REX2) -8c: JL/JNGE Jz (f64) (!REX2) -8d: JNL/JGE Jz (f64) (!REX2) -8e: JLE/JNG Jz (f64) (!REX2) -8f: JNLE/JG Jz (f64) (!REX2) +80: JO Jz (f64),(!REX2) +81: JNO Jz (f64),(!REX2) +82: JB/JC/JNAE Jz (f64),(!REX2) +83: JAE/JNB/JNC Jz (f64),(!REX2) +84: JE/JZ Jz (f64),(!REX2) +85: JNE/JNZ Jz (f64),(!REX2) +86: JBE/JNA Jz (f64),(!REX2) +87: JA/JNBE Jz (f64),(!REX2) +88: JS Jz (f64),(!REX2) +89: JNS Jz (f64),(!REX2) +8a: JP/JPE Jz (f64),(!REX2) +8b: JNP/JPO Jz (f64),(!REX2) +8c: JL/JNGE Jz (f64),(!REX2) +8d: JNL/JGE Jz (f64),(!REX2) +8e: JLE/JNG Jz (f64),(!REX2) +8f: JNLE/JG Jz (f64),(!REX2) # 0x0f 0x90-0x9f 90: SETO Eb | kmovw/q Vk,Wk | kmovb/d Vk,Wk (66) 91: SETNO Eb | kmovw/q Mv,Vk | kmovb/d Mv,Vk (66) @@ -996,8 +996,8 @@ AVXcode: 4 83: Grp1 Ev,Ib (1A),(es) # CTESTSCC instructions are: CTESTB, CTESTBE, CTESTF, CTESTL, CTESTLE, CTESTNB, CTESTNBE, CTESTNL, # CTESTNLE, CTESTNO, CTESTNS, CTESTNZ, CTESTO, CTESTS, CTESTT, CTESTZ -84: CTESTSCC (ev) -85: CTESTSCC (es) | CTESTSCC (66),(es) +84: CTESTSCC Eb,Gb (ev) +85: CTESTSCC Ev,Gv (es) | CTESTSCC Ev,Gv (66),(es) 88: POPCNT Gv,Ev (es) | POPCNT Gv,Ev (66),(es) 8f: POP2 Bq,Rq (000),(11B),(ev) a5: SHLD Ev,Gv,CL (es) | SHLD Ev,Gv,CL (66),(es) |