2017-06-28 15:11:05 +00:00
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/*
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* Copyright (C) 2015-2017 Josh Poimboeuf <jpoimboe@redhat.com>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <string.h>
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#include <stdlib.h>
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#include "check.h"
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#include "elf.h"
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#include "special.h"
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#include "arch.h"
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#include "warn.h"
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#include <linux/hashtable.h>
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#include <linux/kernel.h>
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struct alternative {
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struct list_head list;
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struct instruction *insn;
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};
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const char *objname;
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static bool nofp;
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2017-06-28 15:11:07 +00:00
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struct cfi_state initial_func_cfi;
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2017-06-28 15:11:05 +00:00
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2017-07-11 15:33:42 +00:00
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struct instruction *find_insn(struct objtool_file *file,
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struct section *sec, unsigned long offset)
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2017-06-28 15:11:05 +00:00
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{
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struct instruction *insn;
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hash_for_each_possible(file->insn_hash, insn, hash, offset)
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if (insn->sec == sec && insn->offset == offset)
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return insn;
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return NULL;
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}
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static struct instruction *next_insn_same_sec(struct objtool_file *file,
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struct instruction *insn)
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{
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struct instruction *next = list_next_entry(insn, list);
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2017-06-28 15:11:07 +00:00
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if (!next || &next->list == &file->insn_list || next->sec != insn->sec)
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2017-06-28 15:11:05 +00:00
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return NULL;
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return next;
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}
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static bool gcov_enabled(struct objtool_file *file)
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{
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struct section *sec;
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struct symbol *sym;
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2017-06-28 15:11:07 +00:00
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for_each_sec(file, sec)
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2017-06-28 15:11:05 +00:00
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list_for_each_entry(sym, &sec->symbol_list, list)
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if (!strncmp(sym->name, "__gcov_.", 8))
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return true;
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return false;
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}
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#define func_for_each_insn(file, func, insn) \
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for (insn = find_insn(file, func->sec, func->offset); \
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insn && &insn->list != &file->insn_list && \
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insn->sec == func->sec && \
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insn->offset < func->offset + func->len; \
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insn = list_next_entry(insn, list))
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#define func_for_each_insn_continue_reverse(file, func, insn) \
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for (insn = list_prev_entry(insn, list); \
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&insn->list != &file->insn_list && \
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insn->sec == func->sec && insn->offset >= func->offset; \
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insn = list_prev_entry(insn, list))
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#define sec_for_each_insn_from(file, insn) \
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for (; insn; insn = next_insn_same_sec(file, insn))
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2017-06-28 15:11:07 +00:00
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#define sec_for_each_insn_continue(file, insn) \
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for (insn = next_insn_same_sec(file, insn); insn; \
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insn = next_insn_same_sec(file, insn))
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2017-06-28 15:11:05 +00:00
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/*
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* Check if the function has been manually whitelisted with the
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* STACK_FRAME_NON_STANDARD macro, or if it should be automatically whitelisted
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* due to its use of a context switching instruction.
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*/
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static bool ignore_func(struct objtool_file *file, struct symbol *func)
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{
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struct rela *rela;
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2017-06-30 14:09:34 +00:00
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struct instruction *insn;
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2017-06-28 15:11:05 +00:00
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/* check for STACK_FRAME_NON_STANDARD */
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if (file->whitelist && file->whitelist->rela)
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list_for_each_entry(rela, &file->whitelist->rela->rela_list, list) {
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if (rela->sym->type == STT_SECTION &&
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rela->sym->sec == func->sec &&
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rela->addend == func->offset)
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return true;
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if (rela->sym->type == STT_FUNC && rela->sym == func)
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return true;
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}
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2017-06-30 14:09:34 +00:00
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/* check if it has a context switching instruction */
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func_for_each_insn(file, func, insn)
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if (insn->type == INSN_CONTEXT_SWITCH)
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return true;
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2017-06-28 15:11:05 +00:00
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return false;
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}
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/*
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* This checks to see if the given function is a "noreturn" function.
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*
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* For global functions which are outside the scope of this object file, we
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* have to keep a manual list of them.
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*
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* For local functions, we have to detect them manually by simply looking for
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* the lack of a return instruction.
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*
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* Returns:
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* -1: error
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* 0: no dead end
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* 1: dead end
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*/
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static int __dead_end_function(struct objtool_file *file, struct symbol *func,
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int recursion)
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{
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int i;
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struct instruction *insn;
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bool empty = true;
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/*
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* Unfortunately these have to be hard coded because the noreturn
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* attribute isn't provided in ELF data.
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*/
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static const char * const global_noreturns[] = {
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"__stack_chk_fail",
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"panic",
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"do_exit",
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"do_task_dead",
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"__module_put_and_exit",
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"complete_and_exit",
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"kvm_spurious_fault",
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"__reiserfs_panic",
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"lbug_with_loc",
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"fortify_panic",
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};
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if (func->bind == STB_WEAK)
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return 0;
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if (func->bind == STB_GLOBAL)
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for (i = 0; i < ARRAY_SIZE(global_noreturns); i++)
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if (!strcmp(func->name, global_noreturns[i]))
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return 1;
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if (!func->sec)
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return 0;
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func_for_each_insn(file, func, insn) {
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empty = false;
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if (insn->type == INSN_RETURN)
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return 0;
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}
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if (empty)
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return 0;
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/*
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* A function can have a sibling call instead of a return. In that
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* case, the function's dead-end status depends on whether the target
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* of the sibling call returns.
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*/
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func_for_each_insn(file, func, insn) {
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if (insn->sec != func->sec ||
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insn->offset >= func->offset + func->len)
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break;
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if (insn->type == INSN_JUMP_UNCONDITIONAL) {
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struct instruction *dest = insn->jump_dest;
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struct symbol *dest_func;
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if (!dest)
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/* sibling call to another file */
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return 0;
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if (dest->sec != func->sec ||
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dest->offset < func->offset ||
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dest->offset >= func->offset + func->len) {
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/* local sibling call */
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dest_func = find_symbol_by_offset(dest->sec,
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dest->offset);
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if (!dest_func)
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continue;
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if (recursion == 5) {
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WARN_FUNC("infinite recursion (objtool bug!)",
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dest->sec, dest->offset);
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return -1;
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}
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return __dead_end_function(file, dest_func,
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recursion + 1);
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}
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}
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if (insn->type == INSN_JUMP_DYNAMIC && list_empty(&insn->alts))
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/* sibling call */
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return 0;
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}
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return 1;
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}
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static int dead_end_function(struct objtool_file *file, struct symbol *func)
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{
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return __dead_end_function(file, func, 0);
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}
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2017-06-28 15:11:07 +00:00
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static void clear_insn_state(struct insn_state *state)
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{
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int i;
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memset(state, 0, sizeof(*state));
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state->cfa.base = CFI_UNDEFINED;
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for (i = 0; i < CFI_NUM_REGS; i++)
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state->regs[i].base = CFI_UNDEFINED;
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state->drap_reg = CFI_UNDEFINED;
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}
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2017-06-28 15:11:05 +00:00
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/*
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* Call the arch-specific instruction decoder for all the instructions and add
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* them to the global instruction list.
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*/
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static int decode_instructions(struct objtool_file *file)
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{
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struct section *sec;
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struct symbol *func;
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unsigned long offset;
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struct instruction *insn;
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int ret;
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2017-06-28 15:11:07 +00:00
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for_each_sec(file, sec) {
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2017-06-28 15:11:05 +00:00
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if (!(sec->sh.sh_flags & SHF_EXECINSTR))
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continue;
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2017-07-11 15:33:42 +00:00
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if (strcmp(sec->name, ".altinstr_replacement") &&
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strcmp(sec->name, ".altinstr_aux") &&
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strncmp(sec->name, ".discard.", 9))
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sec->text = true;
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2017-06-28 15:11:05 +00:00
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for (offset = 0; offset < sec->len; offset += insn->len) {
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insn = malloc(sizeof(*insn));
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2017-06-28 15:11:07 +00:00
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if (!insn) {
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WARN("malloc failed");
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return -1;
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}
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2017-06-28 15:11:05 +00:00
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memset(insn, 0, sizeof(*insn));
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INIT_LIST_HEAD(&insn->alts);
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2017-06-28 15:11:07 +00:00
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clear_insn_state(&insn->state);
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2017-06-28 15:11:05 +00:00
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insn->sec = sec;
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insn->offset = offset;
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ret = arch_decode_instruction(file->elf, sec, offset,
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sec->len - offset,
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&insn->len, &insn->type,
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2017-06-28 15:11:07 +00:00
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&insn->immediate,
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&insn->stack_op);
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2017-06-28 15:11:05 +00:00
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if (ret)
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return ret;
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if (!insn->type || insn->type > INSN_LAST) {
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WARN_FUNC("invalid instruction type %d",
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insn->sec, insn->offset, insn->type);
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return -1;
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}
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hash_add(file->insn_hash, &insn->hash, insn->offset);
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list_add_tail(&insn->list, &file->insn_list);
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}
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list_for_each_entry(func, &sec->symbol_list, list) {
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if (func->type != STT_FUNC)
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continue;
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if (!find_insn(file, sec, func->offset)) {
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WARN("%s(): can't find starting instruction",
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func->name);
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return -1;
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}
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func_for_each_insn(file, func, insn)
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if (!insn->func)
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insn->func = func;
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}
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}
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return 0;
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}
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/*
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* Find all uses of the unreachable() macro, which are code path dead ends.
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*/
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static int add_dead_ends(struct objtool_file *file)
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{
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struct section *sec;
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struct rela *rela;
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struct instruction *insn;
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bool found;
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sec = find_section_by_name(file->elf, ".rela.discard.unreachable");
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if (!sec)
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return 0;
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list_for_each_entry(rela, &sec->rela_list, list) {
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if (rela->sym->type != STT_SECTION) {
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WARN("unexpected relocation symbol type in %s", sec->name);
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return -1;
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}
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insn = find_insn(file, rela->sym->sec, rela->addend);
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if (insn)
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insn = list_prev_entry(insn, list);
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else if (rela->addend == rela->sym->sec->len) {
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found = false;
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list_for_each_entry_reverse(insn, &file->insn_list, list) {
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if (insn->sec == rela->sym->sec) {
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found = true;
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break;
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}
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}
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if (!found) {
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WARN("can't find unreachable insn at %s+0x%x",
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rela->sym->sec->name, rela->addend);
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return -1;
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}
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} else {
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WARN("can't find unreachable insn at %s+0x%x",
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rela->sym->sec->name, rela->addend);
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return -1;
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}
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insn->dead_end = true;
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}
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return 0;
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}
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/*
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* Warnings shouldn't be reported for ignored functions.
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*/
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static void add_ignores(struct objtool_file *file)
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{
|
|
|
|
struct instruction *insn;
|
|
|
|
struct section *sec;
|
|
|
|
struct symbol *func;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
for_each_sec(file, sec) {
|
2017-06-28 15:11:05 +00:00
|
|
|
list_for_each_entry(func, &sec->symbol_list, list) {
|
|
|
|
if (func->type != STT_FUNC)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (!ignore_func(file, func))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
func_for_each_insn(file, func, insn)
|
2017-06-28 15:11:07 +00:00
|
|
|
insn->ignore = true;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Find the destination instructions for all jumps.
|
|
|
|
*/
|
|
|
|
static int add_jump_destinations(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct instruction *insn;
|
|
|
|
struct rela *rela;
|
|
|
|
struct section *dest_sec;
|
|
|
|
unsigned long dest_off;
|
|
|
|
|
|
|
|
for_each_insn(file, insn) {
|
|
|
|
if (insn->type != INSN_JUMP_CONDITIONAL &&
|
|
|
|
insn->type != INSN_JUMP_UNCONDITIONAL)
|
|
|
|
continue;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
if (insn->ignore)
|
2017-06-28 15:11:05 +00:00
|
|
|
continue;
|
|
|
|
|
|
|
|
rela = find_rela_by_dest_range(insn->sec, insn->offset,
|
|
|
|
insn->len);
|
|
|
|
if (!rela) {
|
|
|
|
dest_sec = insn->sec;
|
|
|
|
dest_off = insn->offset + insn->len + insn->immediate;
|
|
|
|
} else if (rela->sym->type == STT_SECTION) {
|
|
|
|
dest_sec = rela->sym->sec;
|
|
|
|
dest_off = rela->addend + 4;
|
|
|
|
} else if (rela->sym->sec->idx) {
|
|
|
|
dest_sec = rela->sym->sec;
|
|
|
|
dest_off = rela->sym->sym.st_value + rela->addend + 4;
|
|
|
|
} else {
|
|
|
|
/* sibling call */
|
|
|
|
insn->jump_dest = 0;
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
|
|
|
insn->jump_dest = find_insn(file, dest_sec, dest_off);
|
|
|
|
if (!insn->jump_dest) {
|
|
|
|
|
|
|
|
/*
|
|
|
|
* This is a special case where an alt instruction
|
|
|
|
* jumps past the end of the section. These are
|
|
|
|
* handled later in handle_group_alt().
|
|
|
|
*/
|
|
|
|
if (!strcmp(insn->sec->name, ".altinstr_replacement"))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
WARN_FUNC("can't find jump dest instruction at %s+0x%lx",
|
|
|
|
insn->sec, insn->offset, dest_sec->name,
|
|
|
|
dest_off);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Find the destination instructions for all calls.
|
|
|
|
*/
|
|
|
|
static int add_call_destinations(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct instruction *insn;
|
|
|
|
unsigned long dest_off;
|
|
|
|
struct rela *rela;
|
|
|
|
|
|
|
|
for_each_insn(file, insn) {
|
|
|
|
if (insn->type != INSN_CALL)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
rela = find_rela_by_dest_range(insn->sec, insn->offset,
|
|
|
|
insn->len);
|
|
|
|
if (!rela) {
|
|
|
|
dest_off = insn->offset + insn->len + insn->immediate;
|
|
|
|
insn->call_dest = find_symbol_by_offset(insn->sec,
|
|
|
|
dest_off);
|
|
|
|
if (!insn->call_dest) {
|
|
|
|
WARN_FUNC("can't find call dest symbol at offset 0x%lx",
|
|
|
|
insn->sec, insn->offset, dest_off);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
} else if (rela->sym->type == STT_SECTION) {
|
|
|
|
insn->call_dest = find_symbol_by_offset(rela->sym->sec,
|
|
|
|
rela->addend+4);
|
|
|
|
if (!insn->call_dest ||
|
|
|
|
insn->call_dest->type != STT_FUNC) {
|
|
|
|
WARN_FUNC("can't find call dest symbol at %s+0x%x",
|
|
|
|
insn->sec, insn->offset,
|
|
|
|
rela->sym->sec->name,
|
|
|
|
rela->addend + 4);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
} else
|
|
|
|
insn->call_dest = rela->sym;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The .alternatives section requires some extra special care, over and above
|
|
|
|
* what other special sections require:
|
|
|
|
*
|
|
|
|
* 1. Because alternatives are patched in-place, we need to insert a fake jump
|
|
|
|
* instruction at the end so that validate_branch() skips all the original
|
|
|
|
* replaced instructions when validating the new instruction path.
|
|
|
|
*
|
|
|
|
* 2. An added wrinkle is that the new instruction length might be zero. In
|
|
|
|
* that case the old instructions are replaced with noops. We simulate that
|
|
|
|
* by creating a fake jump as the only new instruction.
|
|
|
|
*
|
|
|
|
* 3. In some cases, the alternative section includes an instruction which
|
|
|
|
* conditionally jumps to the _end_ of the entry. We have to modify these
|
|
|
|
* jumps' destinations to point back to .text rather than the end of the
|
|
|
|
* entry in .altinstr_replacement.
|
|
|
|
*
|
|
|
|
* 4. It has been requested that we don't validate the !POPCNT feature path
|
|
|
|
* which is a "very very small percentage of machines".
|
|
|
|
*/
|
|
|
|
static int handle_group_alt(struct objtool_file *file,
|
|
|
|
struct special_alt *special_alt,
|
|
|
|
struct instruction *orig_insn,
|
|
|
|
struct instruction **new_insn)
|
|
|
|
{
|
|
|
|
struct instruction *last_orig_insn, *last_new_insn, *insn, *fake_jump;
|
|
|
|
unsigned long dest_off;
|
|
|
|
|
|
|
|
last_orig_insn = NULL;
|
|
|
|
insn = orig_insn;
|
|
|
|
sec_for_each_insn_from(file, insn) {
|
|
|
|
if (insn->offset >= special_alt->orig_off + special_alt->orig_len)
|
|
|
|
break;
|
|
|
|
|
|
|
|
if (special_alt->skip_orig)
|
|
|
|
insn->type = INSN_NOP;
|
|
|
|
|
|
|
|
insn->alt_group = true;
|
|
|
|
last_orig_insn = insn;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!next_insn_same_sec(file, last_orig_insn)) {
|
|
|
|
WARN("%s: don't know how to handle alternatives at end of section",
|
|
|
|
special_alt->orig_sec->name);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
fake_jump = malloc(sizeof(*fake_jump));
|
|
|
|
if (!fake_jump) {
|
|
|
|
WARN("malloc failed");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
memset(fake_jump, 0, sizeof(*fake_jump));
|
|
|
|
INIT_LIST_HEAD(&fake_jump->alts);
|
2017-06-28 15:11:07 +00:00
|
|
|
clear_insn_state(&fake_jump->state);
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
fake_jump->sec = special_alt->new_sec;
|
|
|
|
fake_jump->offset = -1;
|
|
|
|
fake_jump->type = INSN_JUMP_UNCONDITIONAL;
|
|
|
|
fake_jump->jump_dest = list_next_entry(last_orig_insn, list);
|
2017-06-28 15:11:07 +00:00
|
|
|
fake_jump->ignore = true;
|
2017-06-28 15:11:05 +00:00
|
|
|
|
|
|
|
if (!special_alt->new_len) {
|
|
|
|
*new_insn = fake_jump;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
last_new_insn = NULL;
|
|
|
|
insn = *new_insn;
|
|
|
|
sec_for_each_insn_from(file, insn) {
|
|
|
|
if (insn->offset >= special_alt->new_off + special_alt->new_len)
|
|
|
|
break;
|
|
|
|
|
|
|
|
last_new_insn = insn;
|
|
|
|
|
|
|
|
if (insn->type != INSN_JUMP_CONDITIONAL &&
|
|
|
|
insn->type != INSN_JUMP_UNCONDITIONAL)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (!insn->immediate)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
dest_off = insn->offset + insn->len + insn->immediate;
|
|
|
|
if (dest_off == special_alt->new_off + special_alt->new_len)
|
|
|
|
insn->jump_dest = fake_jump;
|
|
|
|
|
|
|
|
if (!insn->jump_dest) {
|
|
|
|
WARN_FUNC("can't find alternative jump destination",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!last_new_insn) {
|
|
|
|
WARN_FUNC("can't find last new alternative instruction",
|
|
|
|
special_alt->new_sec, special_alt->new_off);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
list_add(&fake_jump->list, &last_new_insn->list);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* A jump table entry can either convert a nop to a jump or a jump to a nop.
|
|
|
|
* If the original instruction is a jump, make the alt entry an effective nop
|
|
|
|
* by just skipping the original instruction.
|
|
|
|
*/
|
|
|
|
static int handle_jump_alt(struct objtool_file *file,
|
|
|
|
struct special_alt *special_alt,
|
|
|
|
struct instruction *orig_insn,
|
|
|
|
struct instruction **new_insn)
|
|
|
|
{
|
|
|
|
if (orig_insn->type == INSN_NOP)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
|
|
|
|
WARN_FUNC("unsupported instruction at jump label",
|
|
|
|
orig_insn->sec, orig_insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
*new_insn = list_next_entry(orig_insn, list);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Read all the special sections which have alternate instructions which can be
|
|
|
|
* patched in or redirected to at runtime. Each instruction having alternate
|
|
|
|
* instruction(s) has them added to its insn->alts list, which will be
|
|
|
|
* traversed in validate_branch().
|
|
|
|
*/
|
|
|
|
static int add_special_section_alts(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct list_head special_alts;
|
|
|
|
struct instruction *orig_insn, *new_insn;
|
|
|
|
struct special_alt *special_alt, *tmp;
|
|
|
|
struct alternative *alt;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = special_get_alts(file->elf, &special_alts);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
list_for_each_entry_safe(special_alt, tmp, &special_alts, list) {
|
|
|
|
alt = malloc(sizeof(*alt));
|
|
|
|
if (!alt) {
|
|
|
|
WARN("malloc failed");
|
|
|
|
ret = -1;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
orig_insn = find_insn(file, special_alt->orig_sec,
|
|
|
|
special_alt->orig_off);
|
|
|
|
if (!orig_insn) {
|
|
|
|
WARN_FUNC("special: can't find orig instruction",
|
|
|
|
special_alt->orig_sec, special_alt->orig_off);
|
|
|
|
ret = -1;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
new_insn = NULL;
|
|
|
|
if (!special_alt->group || special_alt->new_len) {
|
|
|
|
new_insn = find_insn(file, special_alt->new_sec,
|
|
|
|
special_alt->new_off);
|
|
|
|
if (!new_insn) {
|
|
|
|
WARN_FUNC("special: can't find new instruction",
|
|
|
|
special_alt->new_sec,
|
|
|
|
special_alt->new_off);
|
|
|
|
ret = -1;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
if (special_alt->group) {
|
|
|
|
ret = handle_group_alt(file, special_alt, orig_insn,
|
|
|
|
&new_insn);
|
|
|
|
if (ret)
|
|
|
|
goto out;
|
|
|
|
} else if (special_alt->jump_or_nop) {
|
|
|
|
ret = handle_jump_alt(file, special_alt, orig_insn,
|
|
|
|
&new_insn);
|
|
|
|
if (ret)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
alt->insn = new_insn;
|
|
|
|
list_add_tail(&alt->list, &orig_insn->alts);
|
|
|
|
|
|
|
|
list_del(&special_alt->list);
|
|
|
|
free(special_alt);
|
|
|
|
}
|
|
|
|
|
|
|
|
out:
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int add_switch_table(struct objtool_file *file, struct symbol *func,
|
|
|
|
struct instruction *insn, struct rela *table,
|
|
|
|
struct rela *next_table)
|
|
|
|
{
|
|
|
|
struct rela *rela = table;
|
|
|
|
struct instruction *alt_insn;
|
|
|
|
struct alternative *alt;
|
|
|
|
|
|
|
|
list_for_each_entry_from(rela, &file->rodata->rela->rela_list, list) {
|
|
|
|
if (rela == next_table)
|
|
|
|
break;
|
|
|
|
|
|
|
|
if (rela->sym->sec != insn->sec ||
|
|
|
|
rela->addend <= func->offset ||
|
|
|
|
rela->addend >= func->offset + func->len)
|
|
|
|
break;
|
|
|
|
|
|
|
|
alt_insn = find_insn(file, insn->sec, rela->addend);
|
|
|
|
if (!alt_insn) {
|
|
|
|
WARN("%s: can't find instruction at %s+0x%x",
|
|
|
|
file->rodata->rela->name, insn->sec->name,
|
|
|
|
rela->addend);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
alt = malloc(sizeof(*alt));
|
|
|
|
if (!alt) {
|
|
|
|
WARN("malloc failed");
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
alt->insn = alt_insn;
|
|
|
|
list_add_tail(&alt->list, &insn->alts);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* find_switch_table() - Given a dynamic jump, find the switch jump table in
|
|
|
|
* .rodata associated with it.
|
|
|
|
*
|
|
|
|
* There are 3 basic patterns:
|
|
|
|
*
|
|
|
|
* 1. jmpq *[rodata addr](,%reg,8)
|
|
|
|
*
|
|
|
|
* This is the most common case by far. It jumps to an address in a simple
|
|
|
|
* jump table which is stored in .rodata.
|
|
|
|
*
|
|
|
|
* 2. jmpq *[rodata addr](%rip)
|
|
|
|
*
|
|
|
|
* This is caused by a rare GCC quirk, currently only seen in three driver
|
|
|
|
* functions in the kernel, only with certain obscure non-distro configs.
|
|
|
|
*
|
|
|
|
* As part of an optimization, GCC makes a copy of an existing switch jump
|
|
|
|
* table, modifies it, and then hard-codes the jump (albeit with an indirect
|
|
|
|
* jump) to use a single entry in the table. The rest of the jump table and
|
|
|
|
* some of its jump targets remain as dead code.
|
|
|
|
*
|
|
|
|
* In such a case we can just crudely ignore all unreachable instruction
|
|
|
|
* warnings for the entire object file. Ideally we would just ignore them
|
|
|
|
* for the function, but that would require redesigning the code quite a
|
|
|
|
* bit. And honestly that's just not worth doing: unreachable instruction
|
|
|
|
* warnings are of questionable value anyway, and this is such a rare issue.
|
|
|
|
*
|
|
|
|
* 3. mov [rodata addr],%reg1
|
|
|
|
* ... some instructions ...
|
|
|
|
* jmpq *(%reg1,%reg2,8)
|
|
|
|
*
|
|
|
|
* This is a fairly uncommon pattern which is new for GCC 6. As of this
|
|
|
|
* writing, there are 11 occurrences of it in the allmodconfig kernel.
|
|
|
|
*
|
|
|
|
* TODO: Once we have DWARF CFI and smarter instruction decoding logic,
|
|
|
|
* ensure the same register is used in the mov and jump instructions.
|
|
|
|
*/
|
|
|
|
static struct rela *find_switch_table(struct objtool_file *file,
|
|
|
|
struct symbol *func,
|
|
|
|
struct instruction *insn)
|
|
|
|
{
|
|
|
|
struct rela *text_rela, *rodata_rela;
|
|
|
|
struct instruction *orig_insn = insn;
|
|
|
|
|
|
|
|
text_rela = find_rela_by_dest_range(insn->sec, insn->offset, insn->len);
|
|
|
|
if (text_rela && text_rela->sym == file->rodata->sym) {
|
|
|
|
/* case 1 */
|
|
|
|
rodata_rela = find_rela_by_dest(file->rodata,
|
|
|
|
text_rela->addend);
|
|
|
|
if (rodata_rela)
|
|
|
|
return rodata_rela;
|
|
|
|
|
|
|
|
/* case 2 */
|
|
|
|
rodata_rela = find_rela_by_dest(file->rodata,
|
|
|
|
text_rela->addend + 4);
|
|
|
|
if (!rodata_rela)
|
|
|
|
return NULL;
|
|
|
|
file->ignore_unreachables = true;
|
|
|
|
return rodata_rela;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* case 3 */
|
|
|
|
func_for_each_insn_continue_reverse(file, func, insn) {
|
|
|
|
if (insn->type == INSN_JUMP_DYNAMIC)
|
|
|
|
break;
|
|
|
|
|
|
|
|
/* allow small jumps within the range */
|
|
|
|
if (insn->type == INSN_JUMP_UNCONDITIONAL &&
|
|
|
|
insn->jump_dest &&
|
|
|
|
(insn->jump_dest->offset <= insn->offset ||
|
|
|
|
insn->jump_dest->offset > orig_insn->offset))
|
|
|
|
break;
|
|
|
|
|
|
|
|
/* look for a relocation which references .rodata */
|
|
|
|
text_rela = find_rela_by_dest_range(insn->sec, insn->offset,
|
|
|
|
insn->len);
|
|
|
|
if (!text_rela || text_rela->sym != file->rodata->sym)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Make sure the .rodata address isn't associated with a
|
|
|
|
* symbol. gcc jump tables are anonymous data.
|
|
|
|
*/
|
|
|
|
if (find_symbol_containing(file->rodata, text_rela->addend))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
return find_rela_by_dest(file->rodata, text_rela->addend);
|
|
|
|
}
|
|
|
|
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int add_func_switch_tables(struct objtool_file *file,
|
|
|
|
struct symbol *func)
|
|
|
|
{
|
|
|
|
struct instruction *insn, *prev_jump = NULL;
|
|
|
|
struct rela *rela, *prev_rela = NULL;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
func_for_each_insn(file, func, insn) {
|
|
|
|
if (insn->type != INSN_JUMP_DYNAMIC)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
rela = find_switch_table(file, func, insn);
|
|
|
|
if (!rela)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We found a switch table, but we don't know yet how big it
|
|
|
|
* is. Don't add it until we reach the end of the function or
|
|
|
|
* the beginning of another switch table in the same function.
|
|
|
|
*/
|
|
|
|
if (prev_jump) {
|
|
|
|
ret = add_switch_table(file, func, prev_jump, prev_rela,
|
|
|
|
rela);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
prev_jump = insn;
|
|
|
|
prev_rela = rela;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (prev_jump) {
|
|
|
|
ret = add_switch_table(file, func, prev_jump, prev_rela, NULL);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* For some switch statements, gcc generates a jump table in the .rodata
|
|
|
|
* section which contains a list of addresses within the function to jump to.
|
|
|
|
* This finds these jump tables and adds them to the insn->alts lists.
|
|
|
|
*/
|
|
|
|
static int add_switch_table_alts(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct section *sec;
|
|
|
|
struct symbol *func;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
if (!file->rodata || !file->rodata->rela)
|
|
|
|
return 0;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
for_each_sec(file, sec) {
|
2017-06-28 15:11:05 +00:00
|
|
|
list_for_each_entry(func, &sec->symbol_list, list) {
|
|
|
|
if (func->type != STT_FUNC)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
ret = add_func_switch_tables(file, func);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int decode_sections(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = decode_instructions(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
ret = add_dead_ends(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
add_ignores(file);
|
|
|
|
|
|
|
|
ret = add_jump_destinations(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
ret = add_call_destinations(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
ret = add_special_section_alts(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
ret = add_switch_table_alts(file);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static bool is_fentry_call(struct instruction *insn)
|
|
|
|
{
|
|
|
|
if (insn->type == INSN_CALL &&
|
|
|
|
insn->call_dest->type == STT_NOTYPE &&
|
|
|
|
!strcmp(insn->call_dest->name, "__fentry__"))
|
|
|
|
return true;
|
|
|
|
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
static bool has_modified_stack_frame(struct insn_state *state)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
2017-06-28 15:11:07 +00:00
|
|
|
int i;
|
|
|
|
|
|
|
|
if (state->cfa.base != initial_func_cfi.cfa.base ||
|
|
|
|
state->cfa.offset != initial_func_cfi.cfa.offset ||
|
|
|
|
state->stack_size != initial_func_cfi.cfa.offset ||
|
|
|
|
state->drap)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
for (i = 0; i < CFI_NUM_REGS; i++)
|
|
|
|
if (state->regs[i].base != initial_func_cfi.regs[i].base ||
|
|
|
|
state->regs[i].offset != initial_func_cfi.regs[i].offset)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
static bool has_valid_stack_frame(struct insn_state *state)
|
|
|
|
{
|
|
|
|
if (state->cfa.base == CFI_BP && state->regs[CFI_BP].base == CFI_CFA &&
|
|
|
|
state->regs[CFI_BP].offset == -16)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
if (state->drap && state->regs[CFI_BP].base == CFI_BP)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
return false;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
static int update_insn_state_regs(struct instruction *insn, struct insn_state *state)
|
|
|
|
{
|
|
|
|
struct cfi_reg *cfa = &state->cfa;
|
|
|
|
struct stack_op *op = &insn->stack_op;
|
|
|
|
|
|
|
|
if (cfa->base != CFI_SP)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* push */
|
|
|
|
if (op->dest.type == OP_DEST_PUSH)
|
|
|
|
cfa->offset += 8;
|
|
|
|
|
|
|
|
/* pop */
|
|
|
|
if (op->src.type == OP_SRC_POP)
|
|
|
|
cfa->offset -= 8;
|
|
|
|
|
|
|
|
/* add immediate to sp */
|
|
|
|
if (op->dest.type == OP_DEST_REG && op->src.type == OP_SRC_ADD &&
|
|
|
|
op->dest.reg == CFI_SP && op->src.reg == CFI_SP)
|
|
|
|
cfa->offset -= op->src.offset;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
static void save_reg(struct insn_state *state, unsigned char reg, int base,
|
|
|
|
int offset)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
2017-06-28 15:11:07 +00:00
|
|
|
if ((arch_callee_saved_reg(reg) ||
|
|
|
|
(state->drap && reg == state->drap_reg)) &&
|
|
|
|
state->regs[reg].base == CFI_UNDEFINED) {
|
|
|
|
state->regs[reg].base = base;
|
|
|
|
state->regs[reg].offset = offset;
|
|
|
|
}
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
static void restore_reg(struct insn_state *state, unsigned char reg)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
2017-06-28 15:11:07 +00:00
|
|
|
state->regs[reg].base = CFI_UNDEFINED;
|
|
|
|
state->regs[reg].offset = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* A note about DRAP stack alignment:
|
|
|
|
*
|
|
|
|
* GCC has the concept of a DRAP register, which is used to help keep track of
|
|
|
|
* the stack pointer when aligning the stack. r10 or r13 is used as the DRAP
|
|
|
|
* register. The typical DRAP pattern is:
|
|
|
|
*
|
|
|
|
* 4c 8d 54 24 08 lea 0x8(%rsp),%r10
|
|
|
|
* 48 83 e4 c0 and $0xffffffffffffffc0,%rsp
|
|
|
|
* 41 ff 72 f8 pushq -0x8(%r10)
|
|
|
|
* 55 push %rbp
|
|
|
|
* 48 89 e5 mov %rsp,%rbp
|
|
|
|
* (more pushes)
|
|
|
|
* 41 52 push %r10
|
|
|
|
* ...
|
|
|
|
* 41 5a pop %r10
|
|
|
|
* (more pops)
|
|
|
|
* 5d pop %rbp
|
|
|
|
* 49 8d 62 f8 lea -0x8(%r10),%rsp
|
|
|
|
* c3 retq
|
|
|
|
*
|
|
|
|
* There are some variations in the epilogues, like:
|
|
|
|
*
|
|
|
|
* 5b pop %rbx
|
|
|
|
* 41 5a pop %r10
|
|
|
|
* 41 5c pop %r12
|
|
|
|
* 41 5d pop %r13
|
|
|
|
* 41 5e pop %r14
|
|
|
|
* c9 leaveq
|
|
|
|
* 49 8d 62 f8 lea -0x8(%r10),%rsp
|
|
|
|
* c3 retq
|
|
|
|
*
|
|
|
|
* and:
|
|
|
|
*
|
|
|
|
* 4c 8b 55 e8 mov -0x18(%rbp),%r10
|
|
|
|
* 48 8b 5d e0 mov -0x20(%rbp),%rbx
|
|
|
|
* 4c 8b 65 f0 mov -0x10(%rbp),%r12
|
|
|
|
* 4c 8b 6d f8 mov -0x8(%rbp),%r13
|
|
|
|
* c9 leaveq
|
|
|
|
* 49 8d 62 f8 lea -0x8(%r10),%rsp
|
|
|
|
* c3 retq
|
|
|
|
*
|
|
|
|
* Sometimes r13 is used as the DRAP register, in which case it's saved and
|
|
|
|
* restored beforehand:
|
|
|
|
*
|
|
|
|
* 41 55 push %r13
|
|
|
|
* 4c 8d 6c 24 10 lea 0x10(%rsp),%r13
|
|
|
|
* 48 83 e4 f0 and $0xfffffffffffffff0,%rsp
|
|
|
|
* ...
|
|
|
|
* 49 8d 65 f0 lea -0x10(%r13),%rsp
|
|
|
|
* 41 5d pop %r13
|
|
|
|
* c3 retq
|
|
|
|
*/
|
|
|
|
static int update_insn_state(struct instruction *insn, struct insn_state *state)
|
|
|
|
{
|
|
|
|
struct stack_op *op = &insn->stack_op;
|
|
|
|
struct cfi_reg *cfa = &state->cfa;
|
|
|
|
struct cfi_reg *regs = state->regs;
|
|
|
|
|
|
|
|
/* stack operations don't make sense with an undefined CFA */
|
|
|
|
if (cfa->base == CFI_UNDEFINED) {
|
|
|
|
if (insn->func) {
|
|
|
|
WARN_FUNC("undefined stack state", insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
if (state->type == ORC_TYPE_REGS || state->type == ORC_TYPE_REGS_IRET)
|
|
|
|
return update_insn_state_regs(insn, state);
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
switch (op->dest.type) {
|
|
|
|
|
|
|
|
case OP_DEST_REG:
|
|
|
|
switch (op->src.type) {
|
|
|
|
|
|
|
|
case OP_SRC_REG:
|
|
|
|
if (cfa->base == op->src.reg && cfa->base == CFI_SP &&
|
|
|
|
op->dest.reg == CFI_BP && regs[CFI_BP].base == CFI_CFA &&
|
|
|
|
regs[CFI_BP].offset == -cfa->offset) {
|
|
|
|
|
|
|
|
/* mov %rsp, %rbp */
|
|
|
|
cfa->base = op->dest.reg;
|
|
|
|
state->bp_scratch = false;
|
|
|
|
} else if (state->drap) {
|
|
|
|
|
|
|
|
/* drap: mov %rsp, %rbp */
|
|
|
|
regs[CFI_BP].base = CFI_BP;
|
|
|
|
regs[CFI_BP].offset = -state->stack_size;
|
|
|
|
state->bp_scratch = false;
|
|
|
|
} else if (!nofp) {
|
|
|
|
|
|
|
|
WARN_FUNC("unknown stack-related register move",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_SRC_ADD:
|
|
|
|
if (op->dest.reg == CFI_SP && op->src.reg == CFI_SP) {
|
|
|
|
|
|
|
|
/* add imm, %rsp */
|
|
|
|
state->stack_size -= op->src.offset;
|
|
|
|
if (cfa->base == CFI_SP)
|
|
|
|
cfa->offset -= op->src.offset;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (op->dest.reg == CFI_SP && op->src.reg == CFI_BP) {
|
|
|
|
|
|
|
|
/* lea disp(%rbp), %rsp */
|
|
|
|
state->stack_size = -(op->src.offset + regs[CFI_BP].offset);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (op->dest.reg != CFI_BP && op->src.reg == CFI_SP &&
|
|
|
|
cfa->base == CFI_SP) {
|
|
|
|
|
|
|
|
/* drap: lea disp(%rsp), %drap */
|
|
|
|
state->drap_reg = op->dest.reg;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (state->drap && op->dest.reg == CFI_SP &&
|
|
|
|
op->src.reg == state->drap_reg) {
|
|
|
|
|
|
|
|
/* drap: lea disp(%drap), %rsp */
|
|
|
|
cfa->base = CFI_SP;
|
|
|
|
cfa->offset = state->stack_size = -op->src.offset;
|
|
|
|
state->drap_reg = CFI_UNDEFINED;
|
|
|
|
state->drap = false;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (op->dest.reg == state->cfa.base) {
|
|
|
|
WARN_FUNC("unsupported stack register modification",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_SRC_AND:
|
|
|
|
if (op->dest.reg != CFI_SP ||
|
|
|
|
(state->drap_reg != CFI_UNDEFINED && cfa->base != CFI_SP) ||
|
|
|
|
(state->drap_reg == CFI_UNDEFINED && cfa->base != CFI_BP)) {
|
|
|
|
WARN_FUNC("unsupported stack pointer realignment",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (state->drap_reg != CFI_UNDEFINED) {
|
|
|
|
/* drap: and imm, %rsp */
|
|
|
|
cfa->base = state->drap_reg;
|
|
|
|
cfa->offset = state->stack_size = 0;
|
|
|
|
state->drap = true;
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Older versions of GCC (4.8ish) realign the stack
|
|
|
|
* without DRAP, with a frame pointer.
|
|
|
|
*/
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_SRC_POP:
|
|
|
|
if (!state->drap && op->dest.type == OP_DEST_REG &&
|
|
|
|
op->dest.reg == cfa->base) {
|
|
|
|
|
|
|
|
/* pop %rbp */
|
|
|
|
cfa->base = CFI_SP;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (regs[op->dest.reg].offset == -state->stack_size) {
|
|
|
|
|
|
|
|
if (state->drap && cfa->base == CFI_BP_INDIRECT &&
|
|
|
|
op->dest.type == OP_DEST_REG &&
|
|
|
|
op->dest.reg == state->drap_reg) {
|
|
|
|
|
|
|
|
/* drap: pop %drap */
|
|
|
|
cfa->base = state->drap_reg;
|
|
|
|
cfa->offset = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
restore_reg(state, op->dest.reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
state->stack_size -= 8;
|
|
|
|
if (cfa->base == CFI_SP)
|
|
|
|
cfa->offset -= 8;
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_SRC_REG_INDIRECT:
|
|
|
|
if (state->drap && op->src.reg == CFI_BP &&
|
|
|
|
op->src.offset == regs[op->dest.reg].offset) {
|
|
|
|
|
|
|
|
/* drap: mov disp(%rbp), %reg */
|
|
|
|
if (op->dest.reg == state->drap_reg) {
|
|
|
|
cfa->base = state->drap_reg;
|
|
|
|
cfa->offset = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
restore_reg(state, op->dest.reg);
|
|
|
|
|
|
|
|
} else if (op->src.reg == cfa->base &&
|
|
|
|
op->src.offset == regs[op->dest.reg].offset + cfa->offset) {
|
|
|
|
|
|
|
|
/* mov disp(%rbp), %reg */
|
|
|
|
/* mov disp(%rsp), %reg */
|
|
|
|
restore_reg(state, op->dest.reg);
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
WARN_FUNC("unknown stack-related instruction",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_DEST_PUSH:
|
|
|
|
state->stack_size += 8;
|
|
|
|
if (cfa->base == CFI_SP)
|
|
|
|
cfa->offset += 8;
|
|
|
|
|
|
|
|
if (op->src.type != OP_SRC_REG)
|
|
|
|
break;
|
|
|
|
|
|
|
|
if (state->drap) {
|
|
|
|
if (op->src.reg == cfa->base && op->src.reg == state->drap_reg) {
|
|
|
|
|
|
|
|
/* drap: push %drap */
|
|
|
|
cfa->base = CFI_BP_INDIRECT;
|
|
|
|
cfa->offset = -state->stack_size;
|
|
|
|
|
|
|
|
/* save drap so we know when to undefine it */
|
|
|
|
save_reg(state, op->src.reg, CFI_CFA, -state->stack_size);
|
|
|
|
|
|
|
|
} else if (op->src.reg == CFI_BP && cfa->base == state->drap_reg) {
|
|
|
|
|
|
|
|
/* drap: push %rbp */
|
|
|
|
state->stack_size = 0;
|
|
|
|
|
|
|
|
} else if (regs[op->src.reg].base == CFI_UNDEFINED) {
|
|
|
|
|
|
|
|
/* drap: push %reg */
|
|
|
|
save_reg(state, op->src.reg, CFI_BP, -state->stack_size);
|
|
|
|
}
|
|
|
|
|
|
|
|
} else {
|
|
|
|
|
|
|
|
/* push %reg */
|
|
|
|
save_reg(state, op->src.reg, CFI_CFA, -state->stack_size);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* detect when asm code uses rbp as a scratch register */
|
|
|
|
if (!nofp && insn->func && op->src.reg == CFI_BP &&
|
|
|
|
cfa->base != CFI_BP)
|
|
|
|
state->bp_scratch = true;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_DEST_REG_INDIRECT:
|
|
|
|
|
|
|
|
if (state->drap) {
|
|
|
|
if (op->src.reg == cfa->base && op->src.reg == state->drap_reg) {
|
|
|
|
|
|
|
|
/* drap: mov %drap, disp(%rbp) */
|
|
|
|
cfa->base = CFI_BP_INDIRECT;
|
|
|
|
cfa->offset = op->dest.offset;
|
|
|
|
|
|
|
|
/* save drap so we know when to undefine it */
|
|
|
|
save_reg(state, op->src.reg, CFI_CFA, op->dest.offset);
|
|
|
|
}
|
|
|
|
|
|
|
|
else if (regs[op->src.reg].base == CFI_UNDEFINED) {
|
|
|
|
|
|
|
|
/* drap: mov reg, disp(%rbp) */
|
|
|
|
save_reg(state, op->src.reg, CFI_BP, op->dest.offset);
|
|
|
|
}
|
|
|
|
|
|
|
|
} else if (op->dest.reg == cfa->base) {
|
|
|
|
|
|
|
|
/* mov reg, disp(%rbp) */
|
|
|
|
/* mov reg, disp(%rsp) */
|
|
|
|
save_reg(state, op->src.reg, CFI_CFA,
|
|
|
|
op->dest.offset - state->cfa.offset);
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_DEST_LEAVE:
|
|
|
|
if ((!state->drap && cfa->base != CFI_BP) ||
|
|
|
|
(state->drap && cfa->base != state->drap_reg)) {
|
|
|
|
WARN_FUNC("leave instruction with modified stack frame",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* leave (mov %rbp, %rsp; pop %rbp) */
|
|
|
|
|
|
|
|
state->stack_size = -state->regs[CFI_BP].offset - 8;
|
|
|
|
restore_reg(state, CFI_BP);
|
|
|
|
|
|
|
|
if (!state->drap) {
|
|
|
|
cfa->base = CFI_SP;
|
|
|
|
cfa->offset -= 8;
|
|
|
|
}
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case OP_DEST_MEM:
|
|
|
|
if (op->src.type != OP_SRC_POP) {
|
|
|
|
WARN_FUNC("unknown stack-related memory operation",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* pop mem */
|
|
|
|
state->stack_size -= 8;
|
|
|
|
if (cfa->base == CFI_SP)
|
|
|
|
cfa->offset -= 8;
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
WARN_FUNC("unknown stack-related instruction",
|
|
|
|
insn->sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static bool insn_state_match(struct instruction *insn, struct insn_state *state)
|
|
|
|
{
|
|
|
|
struct insn_state *state1 = &insn->state, *state2 = state;
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (memcmp(&state1->cfa, &state2->cfa, sizeof(state1->cfa))) {
|
|
|
|
WARN_FUNC("stack state mismatch: cfa1=%d%+d cfa2=%d%+d",
|
|
|
|
insn->sec, insn->offset,
|
|
|
|
state1->cfa.base, state1->cfa.offset,
|
|
|
|
state2->cfa.base, state2->cfa.offset);
|
|
|
|
|
|
|
|
} else if (memcmp(&state1->regs, &state2->regs, sizeof(state1->regs))) {
|
|
|
|
for (i = 0; i < CFI_NUM_REGS; i++) {
|
|
|
|
if (!memcmp(&state1->regs[i], &state2->regs[i],
|
|
|
|
sizeof(struct cfi_reg)))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
WARN_FUNC("stack state mismatch: reg1[%d]=%d%+d reg2[%d]=%d%+d",
|
|
|
|
insn->sec, insn->offset,
|
|
|
|
i, state1->regs[i].base, state1->regs[i].offset,
|
|
|
|
i, state2->regs[i].base, state2->regs[i].offset);
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
} else if (state1->type != state2->type) {
|
|
|
|
WARN_FUNC("stack state mismatch: type1=%d type2=%d",
|
|
|
|
insn->sec, insn->offset, state1->type, state2->type);
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
} else if (state1->drap != state2->drap ||
|
|
|
|
(state1->drap && state1->drap_reg != state2->drap_reg)) {
|
|
|
|
WARN_FUNC("stack state mismatch: drap1=%d(%d) drap2=%d(%d)",
|
|
|
|
insn->sec, insn->offset,
|
|
|
|
state1->drap, state1->drap_reg,
|
|
|
|
state2->drap, state2->drap_reg);
|
|
|
|
|
|
|
|
} else
|
|
|
|
return true;
|
|
|
|
|
|
|
|
return false;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Follow the branch starting at the given instruction, and recursively follow
|
|
|
|
* any other branches (jumps). Meanwhile, track the frame pointer state at
|
|
|
|
* each instruction and validate all the rules described in
|
|
|
|
* tools/objtool/Documentation/stack-validation.txt.
|
|
|
|
*/
|
2017-06-28 15:11:07 +00:00
|
|
|
static int validate_branch(struct objtool_file *file, struct instruction *first,
|
|
|
|
struct insn_state state)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
|
|
|
struct alternative *alt;
|
|
|
|
struct instruction *insn;
|
|
|
|
struct section *sec;
|
|
|
|
struct symbol *func = NULL;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
insn = first;
|
|
|
|
sec = insn->sec;
|
|
|
|
|
|
|
|
if (insn->alt_group && list_empty(&insn->alts)) {
|
|
|
|
WARN_FUNC("don't know how to handle branch to middle of alternative instruction group",
|
|
|
|
sec, insn->offset);
|
2017-06-28 15:11:07 +00:00
|
|
|
return -1;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
while (1) {
|
|
|
|
if (file->c_file && insn->func) {
|
|
|
|
if (func && func != insn->func) {
|
|
|
|
WARN("%s() falls through to next function %s()",
|
|
|
|
func->name, insn->func->name);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
func = insn->func;
|
|
|
|
|
2017-07-07 14:19:42 +00:00
|
|
|
if (func && insn->ignore) {
|
|
|
|
WARN_FUNC("BUG: why am I validating an ignored function?",
|
|
|
|
sec, insn->offset);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
if (insn->visited) {
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!!insn_state_match(insn, &state))
|
2017-06-28 15:11:05 +00:00
|
|
|
return 1;
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
insn->state = state;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
insn->visited = true;
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
list_for_each_entry(alt, &insn->alts, list) {
|
|
|
|
ret = validate_branch(file, alt->insn, state);
|
|
|
|
if (ret)
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
switch (insn->type) {
|
|
|
|
|
|
|
|
case INSN_RETURN:
|
2017-06-28 15:11:07 +00:00
|
|
|
if (func && has_modified_stack_frame(&state)) {
|
|
|
|
WARN_FUNC("return with modified stack frame",
|
2017-06-28 15:11:05 +00:00
|
|
|
sec, insn->offset);
|
|
|
|
return 1;
|
|
|
|
}
|
2017-06-28 15:11:07 +00:00
|
|
|
|
|
|
|
if (state.bp_scratch) {
|
|
|
|
WARN("%s uses BP as a scratch register",
|
|
|
|
insn->func->name);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
case INSN_CALL:
|
2017-06-28 15:11:07 +00:00
|
|
|
if (is_fentry_call(insn))
|
2017-06-28 15:11:05 +00:00
|
|
|
break;
|
|
|
|
|
|
|
|
ret = dead_end_function(file, insn->call_dest);
|
|
|
|
if (ret == 1)
|
|
|
|
return 0;
|
|
|
|
if (ret == -1)
|
|
|
|
return 1;
|
|
|
|
|
|
|
|
/* fallthrough */
|
|
|
|
case INSN_CALL_DYNAMIC:
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!nofp && func && !has_valid_stack_frame(&state)) {
|
2017-06-28 15:11:05 +00:00
|
|
|
WARN_FUNC("call without frame pointer save/setup",
|
|
|
|
sec, insn->offset);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
|
|
|
|
case INSN_JUMP_CONDITIONAL:
|
|
|
|
case INSN_JUMP_UNCONDITIONAL:
|
2017-07-07 14:19:42 +00:00
|
|
|
if (insn->jump_dest &&
|
|
|
|
(!func || !insn->jump_dest->func ||
|
|
|
|
func == insn->jump_dest->func)) {
|
2017-06-28 15:11:05 +00:00
|
|
|
ret = validate_branch(file, insn->jump_dest,
|
|
|
|
state);
|
|
|
|
if (ret)
|
|
|
|
return 1;
|
2017-07-07 14:19:42 +00:00
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
} else if (func && has_modified_stack_frame(&state)) {
|
|
|
|
WARN_FUNC("sibling call from callable instruction with modified stack frame",
|
2017-06-28 15:11:05 +00:00
|
|
|
sec, insn->offset);
|
|
|
|
return 1;
|
2017-07-07 14:19:42 +00:00
|
|
|
}
|
2017-06-28 15:11:05 +00:00
|
|
|
|
|
|
|
if (insn->type == INSN_JUMP_UNCONDITIONAL)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
case INSN_JUMP_DYNAMIC:
|
2017-06-28 15:11:07 +00:00
|
|
|
if (func && list_empty(&insn->alts) &&
|
|
|
|
has_modified_stack_frame(&state)) {
|
|
|
|
WARN_FUNC("sibling call from callable instruction with modified stack frame",
|
2017-06-28 15:11:05 +00:00
|
|
|
sec, insn->offset);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
case INSN_STACK:
|
|
|
|
if (update_insn_state(insn, &state))
|
|
|
|
return -1;
|
|
|
|
|
|
|
|
break;
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
default:
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (insn->dead_end)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
insn = next_insn_same_sec(file, insn);
|
|
|
|
if (!insn) {
|
|
|
|
WARN("%s: unexpected end of section", sec->name);
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static bool is_kasan_insn(struct instruction *insn)
|
|
|
|
{
|
|
|
|
return (insn->type == INSN_CALL &&
|
|
|
|
!strcmp(insn->call_dest->name, "__asan_handle_no_return"));
|
|
|
|
}
|
|
|
|
|
|
|
|
static bool is_ubsan_insn(struct instruction *insn)
|
|
|
|
{
|
|
|
|
return (insn->type == INSN_CALL &&
|
|
|
|
!strcmp(insn->call_dest->name,
|
|
|
|
"__ubsan_handle_builtin_unreachable"));
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
static bool ignore_unreachable_insn(struct instruction *insn)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
if (insn->ignore || insn->type == INSN_NOP)
|
|
|
|
return true;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Ignore any unused exceptions. This can happen when a whitelisted
|
|
|
|
* function has an exception table entry.
|
|
|
|
*/
|
|
|
|
if (!strcmp(insn->sec->name, ".fixup"))
|
2017-06-28 15:11:05 +00:00
|
|
|
return true;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check if this (or a subsequent) instruction is related to
|
|
|
|
* CONFIG_UBSAN or CONFIG_KASAN.
|
|
|
|
*
|
|
|
|
* End the search at 5 instructions to avoid going into the weeds.
|
|
|
|
*/
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!insn->func)
|
|
|
|
return false;
|
2017-06-28 15:11:05 +00:00
|
|
|
for (i = 0; i < 5; i++) {
|
|
|
|
|
|
|
|
if (is_kasan_insn(insn) || is_ubsan_insn(insn))
|
|
|
|
return true;
|
|
|
|
|
|
|
|
if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest) {
|
|
|
|
insn = insn->jump_dest;
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
if (insn->offset + insn->len >= insn->func->offset + insn->func->len)
|
2017-06-28 15:11:05 +00:00
|
|
|
break;
|
|
|
|
insn = list_next_entry(insn, list);
|
|
|
|
}
|
|
|
|
|
|
|
|
return false;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int validate_functions(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct section *sec;
|
|
|
|
struct symbol *func;
|
|
|
|
struct instruction *insn;
|
2017-06-28 15:11:07 +00:00
|
|
|
struct insn_state state;
|
2017-06-28 15:11:05 +00:00
|
|
|
int ret, warnings = 0;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
clear_insn_state(&state);
|
|
|
|
|
|
|
|
state.cfa = initial_func_cfi.cfa;
|
|
|
|
memcpy(&state.regs, &initial_func_cfi.regs,
|
|
|
|
CFI_NUM_REGS * sizeof(struct cfi_reg));
|
|
|
|
state.stack_size = initial_func_cfi.cfa.offset;
|
|
|
|
|
|
|
|
for_each_sec(file, sec) {
|
2017-06-28 15:11:05 +00:00
|
|
|
list_for_each_entry(func, &sec->symbol_list, list) {
|
|
|
|
if (func->type != STT_FUNC)
|
|
|
|
continue;
|
|
|
|
|
|
|
|
insn = find_insn(file, sec, func->offset);
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!insn || insn->ignore)
|
2017-06-28 15:11:05 +00:00
|
|
|
continue;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
ret = validate_branch(file, insn, state);
|
2017-06-28 15:11:05 +00:00
|
|
|
warnings += ret;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return warnings;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
static int validate_reachable_instructions(struct objtool_file *file)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
|
|
|
struct instruction *insn;
|
2017-06-28 15:11:07 +00:00
|
|
|
|
|
|
|
if (file->ignore_unreachables)
|
|
|
|
return 0;
|
2017-06-28 15:11:05 +00:00
|
|
|
|
|
|
|
for_each_insn(file, insn) {
|
2017-06-28 15:11:07 +00:00
|
|
|
if (insn->visited || ignore_unreachable_insn(insn))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* gcov produces a lot of unreachable instructions. If we get
|
|
|
|
* an unreachable warning and the file has gcov enabled, just
|
|
|
|
* ignore it, and all other such warnings for the file. Do
|
|
|
|
* this here because this is an expensive function.
|
|
|
|
*/
|
|
|
|
if (gcov_enabled(file))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
WARN_FUNC("unreachable instruction", insn->sec, insn->offset);
|
|
|
|
return 1;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
return 0;
|
2017-06-28 15:11:05 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static void cleanup(struct objtool_file *file)
|
|
|
|
{
|
|
|
|
struct instruction *insn, *tmpinsn;
|
|
|
|
struct alternative *alt, *tmpalt;
|
|
|
|
|
|
|
|
list_for_each_entry_safe(insn, tmpinsn, &file->insn_list, list) {
|
|
|
|
list_for_each_entry_safe(alt, tmpalt, &insn->alts, list) {
|
|
|
|
list_del(&alt->list);
|
|
|
|
free(alt);
|
|
|
|
}
|
|
|
|
list_del(&insn->list);
|
|
|
|
hash_del(&insn->hash);
|
|
|
|
free(insn);
|
|
|
|
}
|
|
|
|
elf_close(file->elf);
|
|
|
|
}
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
int check(const char *_objname, bool _nofp, bool orc)
|
2017-06-28 15:11:05 +00:00
|
|
|
{
|
|
|
|
struct objtool_file file;
|
|
|
|
int ret, warnings = 0;
|
|
|
|
|
|
|
|
objname = _objname;
|
|
|
|
nofp = _nofp;
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
file.elf = elf_open(objname, orc ? O_RDWR : O_RDONLY);
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!file.elf)
|
2017-06-28 15:11:05 +00:00
|
|
|
return 1;
|
|
|
|
|
|
|
|
INIT_LIST_HEAD(&file.insn_list);
|
|
|
|
hash_init(file.insn_hash);
|
|
|
|
file.whitelist = find_section_by_name(file.elf, ".discard.func_stack_frame_non_standard");
|
|
|
|
file.rodata = find_section_by_name(file.elf, ".rodata");
|
|
|
|
file.ignore_unreachables = false;
|
|
|
|
file.c_file = find_section_by_name(file.elf, ".comment");
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
arch_initial_func_cfi_state(&initial_func_cfi);
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
ret = decode_sections(&file);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
warnings += ret;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
if (list_empty(&file.insn_list))
|
2017-06-28 15:11:05 +00:00
|
|
|
goto out;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
ret = validate_functions(&file);
|
2017-06-28 15:11:05 +00:00
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
warnings += ret;
|
|
|
|
|
2017-06-28 15:11:07 +00:00
|
|
|
if (!warnings) {
|
|
|
|
ret = validate_reachable_instructions(&file);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
warnings += ret;
|
|
|
|
}
|
|
|
|
|
2017-07-11 15:33:42 +00:00
|
|
|
if (orc) {
|
|
|
|
ret = create_orc(&file);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
ret = create_orc_sections(&file);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
ret = elf_write(file.elf);
|
|
|
|
if (ret < 0)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
2017-06-28 15:11:05 +00:00
|
|
|
out:
|
|
|
|
cleanup(&file);
|
|
|
|
|
|
|
|
/* ignore warnings for now until we get all the code cleaned up */
|
|
|
|
if (ret || warnings)
|
|
|
|
return 0;
|
|
|
|
return 0;
|
|
|
|
}
|