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authorLinus Torvalds <torvalds@linux-foundation.org>2021-02-23 09:56:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2021-02-23 09:56:13 -0800
commita56ff24efbba18f4361415597f145f4b5773be3e (patch)
tree228932f20338940071105e14ba044a2b28a6442e /arch/x86/lib
parent79db4d2293eba2ce6265a341bedf6caecad5eeb3 (diff)
parentaafeb14e9da29e323b0605f8f1bae0d45d5f3acf (diff)
downloadlinux-a56ff24efbba18f4361415597f145f4b5773be3e.tar.gz
Merge tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Thomas Gleixner:

 - Make objtool work for big-endian cross compiles

 - Make stack tracking via stack pointer memory operations match
   push/pop semantics to prepare for architectures w/o PUSH/POP
   instructions.

 - Add support for analyzing alternatives

 - Improve retpoline detection and handling

 - Improve assembly code coverage on x86

 - Provide support for inlined stack switching

* tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  objtool: Support stack-swizzle
  objtool,x86: Additionally decode: mov %rsp, (%reg)
  x86/unwind/orc: Change REG_SP_INDIRECT
  x86/power: Support objtool validation in hibernate_asm_64.S
  x86/power: Move restore_registers() to top of the file
  x86/power: Annotate indirect branches as safe
  x86/acpi: Support objtool validation in wakeup_64.S
  x86/acpi: Annotate indirect branch as safe
  x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S
  x86/xen/pvh: Annotate indirect branch as safe
  x86/xen: Support objtool vmlinux.o validation in xen-head.S
  x86/xen: Support objtool validation in xen-asm.S
  objtool: Add xen_start_kernel() to noreturn list
  objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC
  objtool: Add asm version of STACK_FRAME_NON_STANDARD
  objtool: Assume only ELF functions do sibling calls
  x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub
  objtool: Support retpoline jump detection for vmlinux.o
  objtool: Fix ".cold" section suffix check for newer versions of GCC
  objtool: Fix retpoline detection in asm code
  ...
Diffstat (limited to 'arch/x86/lib')
-rw-r--r--arch/x86/lib/insn.c119
-rw-r--r--arch/x86/lib/retpoline.S2
2 files changed, 57 insertions, 64 deletions
diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c
index 404279563891..435630a6ec97 100644
--- a/arch/x86/lib/insn.c
+++ b/arch/x86/lib/insn.c
@@ -5,6 +5,7 @@
  * Copyright (C) IBM Corporation, 2002, 2004, 2009
  */
 
+#include <linux/kernel.h>
 #ifdef __KERNEL__
 #include <linux/string.h>
 #else
@@ -15,15 +16,28 @@
 
 #include <asm/emulate_prefix.h>
 
+#define leXX_to_cpu(t, r)						\
+({									\
+	__typeof__(t) v;						\
+	switch (sizeof(t)) {						\
+	case 4: v = le32_to_cpu(r); break;				\
+	case 2: v = le16_to_cpu(r); break;				\
+	case 1:	v = r; break;						\
+	default:							\
+		BUILD_BUG(); break;					\
+	}								\
+	v;								\
+})
+
 /* Verify next sizeof(t) bytes can be on the same instruction */
 #define validate_next(t, insn, n)	\
 	((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr)
 
 #define __get_next(t, insn)	\
-	({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; })
+	({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); leXX_to_cpu(t, r); })
 
 #define __peek_nbyte_next(t, insn, n)	\
-	({ t r = *(t*)((insn)->next_byte + n); r; })
+	({ t r = *(t*)((insn)->next_byte + n); leXX_to_cpu(t, r); })
 
 #define get_next(t, insn)	\
 	({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); })
@@ -147,9 +161,9 @@ found:
 			b = insn->prefixes.bytes[3];
 			for (i = 0; i < nb; i++)
 				if (prefixes->bytes[i] == lb)
-					prefixes->bytes[i] = b;
+					insn_set_byte(prefixes, i, b);
 		}
-		insn->prefixes.bytes[3] = lb;
+		insn_set_byte(&insn->prefixes, 3, lb);
 	}
 
 	/* Decode REX prefix */
@@ -157,8 +171,7 @@ found:
 		b = peek_next(insn_byte_t, insn);
 		attr = inat_get_opcode_attribute(b);
 		if (inat_is_rex_prefix(attr)) {
-			insn->rex_prefix.value = b;
-			insn->rex_prefix.nbytes = 1;
+			insn_field_set(&insn->rex_prefix, b, 1);
 			insn->next_byte++;
 			if (X86_REX_W(b))
 				/* REX.W overrides opnd_size */
@@ -181,13 +194,13 @@ found:
 			if (X86_MODRM_MOD(b2) != 3)
 				goto vex_end;
 		}
-		insn->vex_prefix.bytes[0] = b;
-		insn->vex_prefix.bytes[1] = b2;
+		insn_set_byte(&insn->vex_prefix, 0, b);
+		insn_set_byte(&insn->vex_prefix, 1, b2);
 		if (inat_is_evex_prefix(attr)) {
 			b2 = peek_nbyte_next(insn_byte_t, insn, 2);
-			insn->vex_prefix.bytes[2] = b2;
+			insn_set_byte(&insn->vex_prefix, 2, b2);
 			b2 = peek_nbyte_next(insn_byte_t, insn, 3);
-			insn->vex_prefix.bytes[3] = b2;
+			insn_set_byte(&insn->vex_prefix, 3, b2);
 			insn->vex_prefix.nbytes = 4;
 			insn->next_byte += 4;
 			if (insn->x86_64 && X86_VEX_W(b2))
@@ -195,7 +208,7 @@ found:
 				insn->opnd_bytes = 8;
 		} else if (inat_is_vex3_prefix(attr)) {
 			b2 = peek_nbyte_next(insn_byte_t, insn, 2);
-			insn->vex_prefix.bytes[2] = b2;
+			insn_set_byte(&insn->vex_prefix, 2, b2);
 			insn->vex_prefix.nbytes = 3;
 			insn->next_byte += 3;
 			if (insn->x86_64 && X86_VEX_W(b2))
@@ -207,7 +220,7 @@ found:
 			 * Makes it easier to decode vex.W, vex.vvvv,
 			 * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0.
 			 */
-			insn->vex_prefix.bytes[2] = b2 & 0x7f;
+			insn_set_byte(&insn->vex_prefix, 2, b2 & 0x7f);
 			insn->vex_prefix.nbytes = 2;
 			insn->next_byte += 2;
 		}
@@ -243,7 +256,7 @@ void insn_get_opcode(struct insn *insn)
 
 	/* Get first opcode */
 	op = get_next(insn_byte_t, insn);
-	opcode->bytes[0] = op;
+	insn_set_byte(opcode, 0, op);
 	opcode->nbytes = 1;
 
 	/* Check if there is VEX prefix or not */
@@ -295,8 +308,7 @@ void insn_get_modrm(struct insn *insn)
 
 	if (inat_has_modrm(insn->attr)) {
 		mod = get_next(insn_byte_t, insn);
-		modrm->value = mod;
-		modrm->nbytes = 1;
+		insn_field_set(modrm, mod, 1);
 		if (inat_is_group(insn->attr)) {
 			pfx_id = insn_last_prefix_id(insn);
 			insn->attr = inat_get_group_attribute(mod, pfx_id,
@@ -334,7 +346,7 @@ int insn_rip_relative(struct insn *insn)
 	 * For rip-relative instructions, the mod field (top 2 bits)
 	 * is zero and the r/m field (bottom 3 bits) is 0x5.
 	 */
-	return (modrm->nbytes && (modrm->value & 0xc7) == 0x5);
+	return (modrm->nbytes && (modrm->bytes[0] & 0xc7) == 0x5);
 }
 
 /**
@@ -353,11 +365,11 @@ void insn_get_sib(struct insn *insn)
 	if (!insn->modrm.got)
 		insn_get_modrm(insn);
 	if (insn->modrm.nbytes) {
-		modrm = (insn_byte_t)insn->modrm.value;
+		modrm = insn->modrm.bytes[0];
 		if (insn->addr_bytes != 2 &&
 		    X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) {
-			insn->sib.value = get_next(insn_byte_t, insn);
-			insn->sib.nbytes = 1;
+			insn_field_set(&insn->sib,
+				       get_next(insn_byte_t, insn), 1);
 		}
 	}
 	insn->sib.got = 1;
@@ -407,19 +419,18 @@ void insn_get_displacement(struct insn *insn)
 		if (mod == 3)
 			goto out;
 		if (mod == 1) {
-			insn->displacement.value = get_next(signed char, insn);
-			insn->displacement.nbytes = 1;
+			insn_field_set(&insn->displacement,
+				       get_next(signed char, insn), 1);
 		} else if (insn->addr_bytes == 2) {
 			if ((mod == 0 && rm == 6) || mod == 2) {
-				insn->displacement.value =
-					 get_next(short, insn);
-				insn->displacement.nbytes = 2;
+				insn_field_set(&insn->displacement,
+					       get_next(short, insn), 2);
 			}
 		} else {
 			if ((mod == 0 && rm == 5) || mod == 2 ||
 			    (mod == 0 && base == 5)) {
-				insn->displacement.value = get_next(int, insn);
-				insn->displacement.nbytes = 4;
+				insn_field_set(&insn->displacement,
+					       get_next(int, insn), 4);
 			}
 		}
 	}
@@ -435,18 +446,14 @@ static int __get_moffset(struct insn *insn)
 {
 	switch (insn->addr_bytes) {
 	case 2:
-		insn->moffset1.value = get_next(short, insn);
-		insn->moffset1.nbytes = 2;
+		insn_field_set(&insn->moffset1, get_next(short, insn), 2);
 		break;
 	case 4:
-		insn->moffset1.value = get_next(int, insn);
-		insn->moffset1.nbytes = 4;
+		insn_field_set(&insn->moffset1, get_next(int, insn), 4);
 		break;
 	case 8:
-		insn->moffset1.value = get_next(int, insn);
-		insn->moffset1.nbytes = 4;
-		insn->moffset2.value = get_next(int, insn);
-		insn->moffset2.nbytes = 4;
+		insn_field_set(&insn->moffset1, get_next(int, insn), 4);
+		insn_field_set(&insn->moffset2, get_next(int, insn), 4);
 		break;
 	default:	/* opnd_bytes must be modified manually */
 		goto err_out;
@@ -464,13 +471,11 @@ static int __get_immv32(struct insn *insn)
 {
 	switch (insn->opnd_bytes) {
 	case 2:
-		insn->immediate.value = get_next(short, insn);
-		insn->immediate.nbytes = 2;
+		insn_field_set(&insn->immediate, get_next(short, insn), 2);
 		break;
 	case 4:
 	case 8:
-		insn->immediate.value = get_next(int, insn);
-		insn->immediate.nbytes = 4;
+		insn_field_set(&insn->immediate, get_next(int, insn), 4);
 		break;
 	default:	/* opnd_bytes must be modified manually */
 		goto err_out;
@@ -487,18 +492,15 @@ static int __get_immv(struct insn *insn)
 {
 	switch (insn->opnd_bytes) {
 	case 2:
-		insn->immediate1.value = get_next(short, insn);
-		insn->immediate1.nbytes = 2;
+		insn_field_set(&insn->immediate1, get_next(short, insn), 2);
 		break;
 	case 4:
-		insn->immediate1.value = get_next(int, insn);
+		insn_field_set(&insn->immediate1, get_next(int, insn), 4);
 		insn->immediate1.nbytes = 4;
 		break;
 	case 8:
-		insn->immediate1.value = get_next(int, insn);
-		insn->immediate1.nbytes = 4;
-		insn->immediate2.value = get_next(int, insn);
-		insn->immediate2.nbytes = 4;
+		insn_field_set(&insn->immediate1, get_next(int, insn), 4);
+		insn_field_set(&insn->immediate2, get_next(int, insn), 4);
 		break;
 	default:	/* opnd_bytes must be modified manually */
 		goto err_out;
@@ -515,12 +517,10 @@ static int __get_immptr(struct insn *insn)
 {
 	switch (insn->opnd_bytes) {
 	case 2:
-		insn->immediate1.value = get_next(short, insn);
-		insn->immediate1.nbytes = 2;
+		insn_field_set(&insn->immediate1, get_next(short, insn), 2);
 		break;
 	case 4:
-		insn->immediate1.value = get_next(int, insn);
-		insn->immediate1.nbytes = 4;
+		insn_field_set(&insn->immediate1, get_next(int, insn), 4);
 		break;
 	case 8:
 		/* ptr16:64 is not exist (no segment) */
@@ -528,8 +528,7 @@ static int __get_immptr(struct insn *insn)
 	default:	/* opnd_bytes must be modified manually */
 		goto err_out;
 	}
-	insn->immediate2.value = get_next(unsigned short, insn);
-	insn->immediate2.nbytes = 2;
+	insn_field_set(&insn->immediate2, get_next(unsigned short, insn), 2);
 	insn->immediate1.got = insn->immediate2.got = 1;
 
 	return 1;
@@ -565,22 +564,17 @@ void insn_get_immediate(struct insn *insn)
 
 	switch (inat_immediate_size(insn->attr)) {
 	case INAT_IMM_BYTE:
-		insn->immediate.value = get_next(signed char, insn);
-		insn->immediate.nbytes = 1;
+		insn_field_set(&insn->immediate, get_next(signed char, insn), 1);
 		break;
 	case INAT_IMM_WORD:
-		insn->immediate.value = get_next(short, insn);
-		insn->immediate.nbytes = 2;
+		insn_field_set(&insn->immediate, get_next(short, insn), 2);
 		break;
 	case INAT_IMM_DWORD:
-		insn->immediate.value = get_next(int, insn);
-		insn->immediate.nbytes = 4;
+		insn_field_set(&insn->immediate, get_next(int, insn), 4);
 		break;
 	case INAT_IMM_QWORD:
-		insn->immediate1.value = get_next(int, insn);
-		insn->immediate1.nbytes = 4;
-		insn->immediate2.value = get_next(int, insn);
-		insn->immediate2.nbytes = 4;
+		insn_field_set(&insn->immediate1, get_next(int, insn), 4);
+		insn_field_set(&insn->immediate2, get_next(int, insn), 4);
 		break;
 	case INAT_IMM_PTR:
 		if (!__get_immptr(insn))
@@ -599,8 +593,7 @@ void insn_get_immediate(struct insn *insn)
 		goto err_out;
 	}
 	if (inat_has_second_immediate(insn->attr)) {
-		insn->immediate2.value = get_next(signed char, insn);
-		insn->immediate2.nbytes = 1;
+		insn_field_set(&insn->immediate2, get_next(signed char, insn), 1);
 	}
 done:
 	insn->immediate.got = 1;
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index b4c43a9b1483..f6fb1d218dcc 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -28,7 +28,7 @@ SYM_FUNC_START_NOALIGN(__x86_retpoline_\reg)
 	jmp	.Lspec_trap_\@
 .Ldo_rop_\@:
 	mov	%\reg, (%_ASM_SP)
-	UNWIND_HINT_RET_OFFSET
+	UNWIND_HINT_FUNC
 	ret
 SYM_FUNC_END(__x86_retpoline_\reg)