Merge tag 'x86-urgent-2023-01-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull misc x86 fixes from Ingo Molnar:
 "Fix a double-free bug, a binutils warning, a header namespace clash
  and a bug in ib_prctl_set()"

* tag 'x86-urgent-2023-01-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/bugs: Flush IBP in ib_prctl_set()
  x86/insn: Avoid namespace clash by separating instruction decoder MMIO type from MMIO trace type
  x86/asm: Fix an assembler warning with current binutils
  x86/kexec: Fix double-free of elf header buffer

Author: torvalds

arch/x86/coco/tdx/tdx.c

@@ -386,8 +386,8 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve)
 {
 	unsigned long *reg, val, vaddr;
 	char buffer[MAX_INSN_SIZE];
+	enum insn_mmio_type mmio;
 	struct insn insn = {};
-	enum mmio_type mmio;
 	int size, extend_size;
 	u8 extend_val = 0;
 
@@ -402,10 +402,10 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve)
 		return -EINVAL;
 
 	mmio = insn_decode_mmio(&insn, &size);
-	if (WARN_ON_ONCE(mmio == MMIO_DECODE_FAILED))
+	if (WARN_ON_ONCE(mmio == INSN_MMIO_DECODE_FAILED))
 		return -EINVAL;
 
-	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {
+	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {
 		reg = insn_get_modrm_reg_ptr(&insn, regs);
 		if (!reg)
 			return -EINVAL;
@@ -426,23 +426,23 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve)
 
 	/* Handle writes first */
 	switch (mmio) {
-	case MMIO_WRITE:
+	case INSN_MMIO_WRITE:
 		memcpy(&val, reg, size);
 		if (!mmio_write(size, ve->gpa, val))
 			return -EIO;
 		return insn.length;
-	case MMIO_WRITE_IMM:
+	case INSN_MMIO_WRITE_IMM:
 		val = insn.immediate.value;
 		if (!mmio_write(size, ve->gpa, val))
 			return -EIO;
 		return insn.length;
-	case MMIO_READ:
-	case MMIO_READ_ZERO_EXTEND:
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ:
+	case INSN_MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		/* Reads are handled below */
 		break;
-	case MMIO_MOVS:
-	case MMIO_DECODE_FAILED:
+	case INSN_MMIO_MOVS:
+	case INSN_MMIO_DECODE_FAILED:
 		/*
 		 * MMIO was accessed with an instruction that could not be
 		 * decoded or handled properly. It was likely not using io.h
@@ -459,15 +459,15 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve)
 		return -EIO;
 
 	switch (mmio) {
-	case MMIO_READ:
+	case INSN_MMIO_READ:
 		/* Zero-extend for 32-bit operation */
 		extend_size = size == 4 ? sizeof(*reg) : 0;
 		break;
-	case MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_ZERO_EXTEND:
 		/* Zero extend based on operand size */
 		extend_size = insn.opnd_bytes;
 		break;
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		/* Sign extend based on operand size */
 		extend_size = insn.opnd_bytes;
 		if (size == 1 && val & BIT(7))

arch/x86/include/asm/insn-eval.h

@@ -32,16 +32,16 @@ int insn_fetch_from_user_inatomic(struct pt_regs *regs,
 bool insn_decode_from_regs(struct insn *insn, struct pt_regs *regs,
 			   unsigned char buf[MAX_INSN_SIZE], int buf_size);
 
-enum mmio_type {
-	MMIO_DECODE_FAILED,
-	MMIO_WRITE,
-	MMIO_WRITE_IMM,
-	MMIO_READ,
-	MMIO_READ_ZERO_EXTEND,
-	MMIO_READ_SIGN_EXTEND,
-	MMIO_MOVS,
+enum insn_mmio_type {
+	INSN_MMIO_DECODE_FAILED,
+	INSN_MMIO_WRITE,
+	INSN_MMIO_WRITE_IMM,
+	INSN_MMIO_READ,
+	INSN_MMIO_READ_ZERO_EXTEND,
+	INSN_MMIO_READ_SIGN_EXTEND,
+	INSN_MMIO_MOVS,
 };
 
-enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes);
+enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes);
 
 #endif /* _ASM_X86_INSN_EVAL_H */

arch/x86/kernel/cpu/bugs.c

@@ -1981,6 +1981,8 @@ static int ib_prctl_set(struct task_struct *task, unsigned long ctrl)
 		if (ctrl == PR_SPEC_FORCE_DISABLE)
 			task_set_spec_ib_force_disable(task);
 		task_update_spec_tif(task);
+		if (task == current)
+			indirect_branch_prediction_barrier();
 		break;
 	default:
 		return -ERANGE;

arch/x86/kernel/crash.c

@@ -401,10 +401,8 @@ int crash_load_segments(struct kimage *image)
 	kbuf.buf_align = ELF_CORE_HEADER_ALIGN;
 	kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
 	ret = kexec_add_buffer(&kbuf);
-	if (ret) {
-		vfree((void *)image->elf_headers);
+	if (ret)
 		return ret;
-	}
 	image->elf_load_addr = kbuf.mem;
 	pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
 		 image->elf_load_addr, kbuf.bufsz, kbuf.memsz);

arch/x86/kernel/sev.c

@@ -1536,32 +1536,32 @@ static enum es_result vc_handle_mmio_movs(struct es_em_ctxt *ctxt,
 static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 {
 	struct insn *insn = &ctxt->insn;
+	enum insn_mmio_type mmio;
 	unsigned int bytes = 0;
-	enum mmio_type mmio;
 	enum es_result ret;
 	u8 sign_byte;
 	long *reg_data;
 
 	mmio = insn_decode_mmio(insn, &bytes);
-	if (mmio == MMIO_DECODE_FAILED)
+	if (mmio == INSN_MMIO_DECODE_FAILED)
 		return ES_DECODE_FAILED;
 
-	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {
+	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {
 		reg_data = insn_get_modrm_reg_ptr(insn, ctxt->regs);
 		if (!reg_data)
 			return ES_DECODE_FAILED;
 	}
 
 	switch (mmio) {
-	case MMIO_WRITE:
+	case INSN_MMIO_WRITE:
 		memcpy(ghcb->shared_buffer, reg_data, bytes);
 		ret = vc_do_mmio(ghcb, ctxt, bytes, false);
 		break;
-	case MMIO_WRITE_IMM:
+	case INSN_MMIO_WRITE_IMM:
 		memcpy(ghcb->shared_buffer, insn->immediate1.bytes, bytes);
 		ret = vc_do_mmio(ghcb, ctxt, bytes, false);
 		break;
-	case MMIO_READ:
+	case INSN_MMIO_READ:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
@@ -1572,7 +1572,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_ZERO_EXTEND:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
@@ -1581,7 +1581,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 		memset(reg_data, 0, insn->opnd_bytes);
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
@@ -1600,7 +1600,7 @@ static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 		memset(reg_data, sign_byte, insn->opnd_bytes);
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_MOVS:
+	case INSN_MMIO_MOVS:
 		ret = vc_handle_mmio_movs(ctxt, bytes);
 		break;
 	default:

arch/x86/lib/insn-eval.c

@@ -1595,16 +1595,16 @@ bool insn_decode_from_regs(struct insn *insn, struct pt_regs *regs,
  * Returns:
  *
  * Type of the instruction. Size of the memory operand is stored in
- * @bytes. If decode failed, MMIO_DECODE_FAILED returned.
+ * @bytes. If decode failed, INSN_MMIO_DECODE_FAILED returned.
  */
-enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
+enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 {
-	enum mmio_type type = MMIO_DECODE_FAILED;
+	enum insn_mmio_type type = INSN_MMIO_DECODE_FAILED;
 
 	*bytes = 0;
 
 	if (insn_get_opcode(insn))
-		return MMIO_DECODE_FAILED;
+		return INSN_MMIO_DECODE_FAILED;
 
 	switch (insn->opcode.bytes[0]) {
 	case 0x88: /* MOV m8,r8 */
@@ -1613,7 +1613,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 	case 0x89: /* MOV m16/m32/m64, r16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_WRITE;
+		type = INSN_MMIO_WRITE;
 		break;
 
 	case 0xc6: /* MOV m8, imm8 */
@@ -1622,7 +1622,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 	case 0xc7: /* MOV m16/m32/m64, imm16/imm32/imm64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_WRITE_IMM;
+		type = INSN_MMIO_WRITE_IMM;
 		break;
 
 	case 0x8a: /* MOV r8, m8 */
@@ -1631,7 +1631,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 	case 0x8b: /* MOV r16/r32/r64, m16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_READ;
+		type = INSN_MMIO_READ;
 		break;
 
 	case 0xa4: /* MOVS m8, m8 */
@@ -1640,7 +1640,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 	case 0xa5: /* MOVS m16/m32/m64, m16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_MOVS;
+		type = INSN_MMIO_MOVS;
 		break;
 
 	case 0x0f: /* Two-byte instruction */
@@ -1651,7 +1651,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 		case 0xb7: /* MOVZX r32/r64, m16 */
 			if (!*bytes)
 				*bytes = 2;
-			type = MMIO_READ_ZERO_EXTEND;
+			type = INSN_MMIO_READ_ZERO_EXTEND;
 			break;
 
 		case 0xbe: /* MOVSX r16/r32/r64, m8 */
@@ -1660,7 +1660,7 @@ enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 		case 0xbf: /* MOVSX r32/r64, m16 */
 			if (!*bytes)
 				*bytes = 2;
-			type = MMIO_READ_SIGN_EXTEND;
+			type = INSN_MMIO_READ_SIGN_EXTEND;
 			break;
 		}
 		break;

arch/x86/lib/iomap_copy_64.S

@@ -10,6 +10,6 @@
  */
 SYM_FUNC_START(__iowrite32_copy)
 	movl %edx,%ecx
-	rep movsd
+	rep movsl
 	RET
 SYM_FUNC_END(__iowrite32_copy)