diff options
Diffstat (limited to 'tools/objtool/check.c')
-rw-r--r-- | tools/objtool/check.c | 109 |
1 files changed, 66 insertions, 43 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 06aaf04e629c..a814917e3f8d 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -136,6 +136,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "panic", "do_exit", "do_task_dead", + "make_task_dead", "__module_put_and_exit", "complete_and_exit", "__reiserfs_panic", @@ -143,7 +144,8 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "fortify_panic", "usercopy_abort", "machine_real_restart", - "rewind_stack_do_exit", + "rewind_stack_and_make_dead", + "cpu_bringup_and_idle", }; if (!func) @@ -161,7 +163,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, return false; insn = find_insn(file, func->sec, func->offset); - if (!insn->func) + if (!insn || !insn->func) return false; func_for_each_insn_all(file, func, insn) { @@ -253,6 +255,7 @@ static int decode_instructions(struct objtool_file *file) } memset(insn, 0, sizeof(*insn)); INIT_LIST_HEAD(&insn->alts); + INIT_LIST_HEAD(&insn->stack_ops); clear_insn_state(&insn->state); insn->sec = sec; @@ -262,7 +265,7 @@ static int decode_instructions(struct objtool_file *file) sec->len - offset, &insn->len, &insn->type, &insn->immediate, - &insn->stack_op); + &insn->stack_ops); if (ret) goto err; @@ -732,6 +735,7 @@ static int handle_group_alt(struct objtool_file *file, } memset(fake_jump, 0, sizeof(*fake_jump)); INIT_LIST_HEAD(&fake_jump->alts); + INIT_LIST_HEAD(&fake_jump->stack_ops); clear_insn_state(&fake_jump->state); fake_jump->sec = special_alt->new_sec; @@ -1403,10 +1407,11 @@ static bool has_valid_stack_frame(struct insn_state *state) return false; } -static int update_insn_state_regs(struct instruction *insn, struct insn_state *state) +static int update_insn_state_regs(struct instruction *insn, + struct insn_state *state, + struct stack_op *op) { struct cfi_reg *cfa = &state->cfa; - struct stack_op *op = &insn->stack_op; if (cfa->base != CFI_SP && cfa->base != CFI_SP_INDIRECT) return 0; @@ -1496,9 +1501,9 @@ static void restore_reg(struct insn_state *state, unsigned char reg) * 41 5d pop %r13 * c3 retq */ -static int update_insn_state(struct instruction *insn, struct insn_state *state) +static int update_insn_state(struct instruction *insn, struct insn_state *state, + struct stack_op *op) { - struct stack_op *op = &insn->stack_op; struct cfi_reg *cfa = &state->cfa; struct cfi_reg *regs = state->regs; @@ -1512,7 +1517,7 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state) } if (state->type == ORC_TYPE_REGS || state->type == ORC_TYPE_REGS_IRET) - return update_insn_state_regs(insn, state); + return update_insn_state_regs(insn, state, op); switch (op->dest.type) { @@ -1851,6 +1856,42 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state) return 0; } +static int handle_insn_ops(struct instruction *insn, struct insn_state *state) +{ + struct stack_op *op; + + list_for_each_entry(op, &insn->stack_ops, list) { + int res; + + res = update_insn_state(insn, state, op); + if (res) + return res; + + if (op->dest.type == OP_DEST_PUSHF) { + if (!state->uaccess_stack) { + state->uaccess_stack = 1; + } else if (state->uaccess_stack >> 31) { + WARN_FUNC("PUSHF stack exhausted", + insn->sec, insn->offset); + return 1; + } + state->uaccess_stack <<= 1; + state->uaccess_stack |= state->uaccess; + } + + if (op->src.type == OP_SRC_POPF) { + if (state->uaccess_stack) { + state->uaccess = state->uaccess_stack & 1; + state->uaccess_stack >>= 1; + if (state->uaccess_stack == 1) + state->uaccess_stack = 0; + } + } + } + + return 0; +} + static bool insn_state_match(struct instruction *insn, struct insn_state *state) { struct insn_state *state1 = &insn->state, *state2 = state; @@ -1944,15 +1985,14 @@ static int validate_sibling_call(struct instruction *insn, struct insn_state *st * tools/objtool/Documentation/stack-validation.txt. */ static int validate_branch(struct objtool_file *file, struct symbol *func, - struct instruction *first, struct insn_state state) + struct instruction *insn, struct insn_state state) { struct alternative *alt; - struct instruction *insn, *next_insn; + struct instruction *next_insn; struct section *sec; u8 visited; int ret; - insn = first; sec = insn->sec; if (insn->alt_group && list_empty(&insn->alts)) { @@ -2005,16 +2045,6 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, } if (!save_insn->visited) { - /* - * Oops, no state to copy yet. - * Hopefully we can reach this - * instruction from another branch - * after the save insn has been - * visited. - */ - if (insn == first) - return 0; - WARN_FUNC("objtool isn't smart enough to handle this CFI save/restore combo", sec, insn->offset); return 1; @@ -2134,6 +2164,20 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, break; + case INSN_EXCEPTION_RETURN: + if (handle_insn_ops(insn, &state)) + return 1; + + /* + * This handles x86's sync_core() case, where we use an + * IRET to self. All 'normal' IRET instructions are in + * STT_NOTYPE entry symbols. + */ + if (func) + break; + + return 0; + case INSN_CONTEXT_SWITCH: if (func && (!next_insn || !next_insn->hint)) { WARN_FUNC("unsupported instruction in callable function", @@ -2143,29 +2187,8 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, return 0; case INSN_STACK: - if (update_insn_state(insn, &state)) + if (handle_insn_ops(insn, &state)) return 1; - - if (insn->stack_op.dest.type == OP_DEST_PUSHF) { - if (!state.uaccess_stack) { - state.uaccess_stack = 1; - } else if (state.uaccess_stack >> 31) { - WARN_FUNC("PUSHF stack exhausted", sec, insn->offset); - return 1; - } - state.uaccess_stack <<= 1; - state.uaccess_stack |= state.uaccess; - } - - if (insn->stack_op.src.type == OP_SRC_POPF) { - if (state.uaccess_stack) { - state.uaccess = state.uaccess_stack & 1; - state.uaccess_stack >>= 1; - if (state.uaccess_stack == 1) - state.uaccess_stack = 0; - } - } - break; case INSN_STAC: |