Merge 4.14-rc5 into char-misc-next

We need the fixes in here to resolve merge issues and for testing.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 63 insertions, 36 deletions

diff --git a/tools/objtool/Documentation/stack-validation.txt b/tools/objtool/Documentation/stack-validation.txt
index 6a1af43862df..3995735a878f 100644
--- a/tools/objtool/Documentation/stack-validation.txt
+++ b/tools/objtool/Documentation/stack-validation.txt
@@ -194,10 +194,10 @@ they mean, and suggestions for how to fix them.
    If it's a GCC-compiled .c file, the error may be because the function
    uses an inline asm() statement which has a "call" instruction.  An
    asm() statement with a call instruction must declare the use of the
-   stack pointer in its output operand.  For example, on x86_64:
+   stack pointer in its output operand.  On x86_64, this means adding
+   the ASM_CALL_CONSTRAINT as an output constraint:
 
-     register void *__sp asm("rsp");
-     asm volatile("call func" : "+r" (__sp));
+     asm volatile("call func" : ASM_CALL_CONSTRAINT);
 
    Otherwise the stack frame may not get created before the call.
 
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 0e8c8ec4fd4e..34a579f806e3 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -208,14 +208,14 @@ int arch_decode_instruction(struct elf *elf, struct section *sec,
 		break;
 
 	case 0x89:
-		if (rex == 0x48 && modrm == 0xe5) {
+		if (rex_w && !rex_r && modrm_mod == 3 && modrm_reg == 4) {
 
-			/* mov %rsp, %rbp */
+			/* mov %rsp, reg */
 			*type = INSN_STACK;
 			op->src.type = OP_SRC_REG;
 			op->src.reg = CFI_SP;
 			op->dest.type = OP_DEST_REG;
-			op->dest.reg = CFI_BP;
+			op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b];
 			break;
 		}
 
@@ -284,11 +284,16 @@ int arch_decode_instruction(struct elf *elf, struct section *sec,
 	case 0x8d:
 		if (sib == 0x24 && rex_w && !rex_b && !rex_x) {
 
-			/* lea disp(%rsp), reg */
 			*type = INSN_STACK;
-			op->src.type = OP_SRC_ADD;
+			if (!insn.displacement.value) {
+				/* lea (%rsp), reg */
+				op->src.type = OP_SRC_REG;
+			} else {
+				/* lea disp(%rsp), reg */
+				op->src.type = OP_SRC_ADD;
+				op->src.offset = insn.displacement.value;
+			}
 			op->src.reg = CFI_SP;
-			op->src.offset = insn.displacement.value;
 			op->dest.type = OP_DEST_REG;
 			op->dest.reg = op_to_cfi_reg[modrm_reg][rex_r];
 
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index f744617c9946..a0c518ecf085 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1203,24 +1203,39 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state)
 		switch (op->src.type) {
 
 		case OP_SRC_REG:
-			if (op->src.reg == CFI_SP && op->dest.reg == CFI_BP) {
+			if (op->src.reg == CFI_SP && op->dest.reg == CFI_BP &&
+			    cfa->base == CFI_SP &&
+			    regs[CFI_BP].base == CFI_CFA &&
+			    regs[CFI_BP].offset == -cfa->offset) {
+
+				/* mov %rsp, %rbp */
+				cfa->base = op->dest.reg;
+				state->bp_scratch = false;
+			}
 
-				if (cfa->base == CFI_SP &&
-				    regs[CFI_BP].base == CFI_CFA &&
-				    regs[CFI_BP].offset == -cfa->offset) {
+			else if (op->src.reg == CFI_SP &&
+				 op->dest.reg == CFI_BP && state->drap) {
 
-					/* mov %rsp, %rbp */
-					cfa->base = op->dest.reg;
-					state->bp_scratch = false;
-				}
+				/* drap: mov %rsp, %rbp */
+				regs[CFI_BP].base = CFI_BP;
+				regs[CFI_BP].offset = -state->stack_size;
+				state->bp_scratch = false;
+			}
 
-				else if (state->drap) {
+			else if (op->src.reg == CFI_SP && cfa->base == CFI_SP) {
 
-					/* drap: mov %rsp, %rbp */
-					regs[CFI_BP].base = CFI_BP;
-					regs[CFI_BP].offset = -state->stack_size;
-					state->bp_scratch = false;
-				}
+				/*
+				 * mov %rsp, %reg
+				 *
+				 * This is needed for the rare case where GCC
+				 * does:
+				 *
+				 *   mov    %rsp, %rax
+				 *   ...
+				 *   mov    %rax, %rsp
+				 */
+				state->vals[op->dest.reg].base = CFI_CFA;
+				state->vals[op->dest.reg].offset = -state->stack_size;
 			}
 
 			else if (op->dest.reg == cfa->base) {
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 6e9f980a7d26..24460155c82c 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -175,19 +175,20 @@ static int read_sections(struct elf *elf)
 			return -1;
 		}
 
-		sec->data = elf_getdata(s, NULL);
-		if (!sec->data) {
-			WARN_ELF("elf_getdata");
-			return -1;
-		}
-
-		if (sec->data->d_off != 0 ||
-		    sec->data->d_size != sec->sh.sh_size) {
-			WARN("unexpected data attributes for %s", sec->name);
-			return -1;
+		if (sec->sh.sh_size != 0) {
+			sec->data = elf_getdata(s, NULL);
+			if (!sec->data) {
+				WARN_ELF("elf_getdata");
+				return -1;
+			}
+			if (sec->data->d_off != 0 ||
+			    sec->data->d_size != sec->sh.sh_size) {
+				WARN("unexpected data attributes for %s",
+				     sec->name);
+				return -1;
+			}
 		}
-
-		sec->len = sec->data->d_size;
+		sec->len = sec->sh.sh_size;
 	}
 
 	/* sanity check, one more call to elf_nextscn() should return NULL */
@@ -508,6 +509,7 @@ struct section *elf_create_rela_section(struct elf *elf, struct section *base)
 	strcat(relaname, base->name);
 
 	sec = elf_create_section(elf, relaname, sizeof(GElf_Rela), 0);
+	free(relaname);
 	if (!sec)
 		return NULL;
 
@@ -561,6 +563,7 @@ int elf_write(struct elf *elf)
 	struct section *sec;
 	Elf_Scn *s;
 
+	/* Update section headers for changed sections: */
 	list_for_each_entry(sec, &elf->sections, list) {
 		if (sec->changed) {
 			s = elf_getscn(elf->elf, sec->idx);
@@ -568,13 +571,17 @@ int elf_write(struct elf *elf)
 				WARN_ELF("elf_getscn");
 				return -1;
 			}
-			if (!gelf_update_shdr (s, &sec->sh)) {
+			if (!gelf_update_shdr(s, &sec->sh)) {
 				WARN_ELF("gelf_update_shdr");
 				return -1;
 			}
 		}
 	}
 
+	/* Make sure the new section header entries get updated properly. */
+	elf_flagelf(elf->elf, ELF_C_SET, ELF_F_DIRTY);
+
+	/* Write all changes to the file. */
 	if (elf_update(elf->elf, ELF_C_WRITE) < 0) {
 		WARN_ELF("elf_update");
 		return -1;