From a92e92d1a749e9bae9828f34f632d56ac2c6d2c3 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 10 Mar 2020 18:07:44 +0100 Subject: [PATCH] objtool: Introduce validate_return() Trivial 'cleanup' to save one indentation level and match validate_call(). Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Acked-by: Josh Poimboeuf Link: https://lkml.kernel.org/r/20200324160923.963996225@infradead.org --- tools/objtool/check.c | 64 ++++++++++++++++++++++++------------------- 1 file changed, 36 insertions(+), 28 deletions(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 6b6178ef4464..da17b5acc504 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1975,6 +1975,41 @@ static int validate_sibling_call(struct instruction *insn, struct insn_state *st return validate_call(insn, state); } +static int validate_return(struct symbol *func, struct instruction *insn, struct insn_state *state) +{ + if (state->uaccess && !func_uaccess_safe(func)) { + WARN_FUNC("return with UACCESS enabled", + insn->sec, insn->offset); + return 1; + } + + if (!state->uaccess && func_uaccess_safe(func)) { + WARN_FUNC("return with UACCESS disabled from a UACCESS-safe function", + insn->sec, insn->offset); + return 1; + } + + if (state->df) { + WARN_FUNC("return with DF set", + insn->sec, insn->offset); + return 1; + } + + if (func && has_modified_stack_frame(state)) { + WARN_FUNC("return with modified stack frame", + insn->sec, insn->offset); + return 1; + } + + if (state->bp_scratch) { + WARN("%s uses BP as a scratch register", + func->name); + return 1; + } + + return 0; +} + /* * Follow the branch starting at the given instruction, and recursively follow * any other branches (jumps). Meanwhile, track the frame pointer state at @@ -2090,34 +2125,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, switch (insn->type) { case INSN_RETURN: - if (state.uaccess && !func_uaccess_safe(func)) { - WARN_FUNC("return with UACCESS enabled", sec, insn->offset); - return 1; - } - - if (!state.uaccess && func_uaccess_safe(func)) { - WARN_FUNC("return with UACCESS disabled from a UACCESS-safe function", sec, insn->offset); - return 1; - } - - if (state.df) { - WARN_FUNC("return with DF set", sec, insn->offset); - return 1; - } - - if (func && has_modified_stack_frame(&state)) { - WARN_FUNC("return with modified stack frame", - sec, insn->offset); - return 1; - } - - if (state.bp_scratch) { - WARN("%s uses BP as a scratch register", - func->name); - return 1; - } - - return 0; + return validate_return(func, insn, &state); case INSN_CALL: case INSN_CALL_DYNAMIC: -- 2.25.1