2020-03-24 16:12:48

by Peter Zijlstra

Subject: [PATCH v3 01/26] objtool: Introduce validate_return()

Trivial 'cleanup' to save one indentation level and match
validate_call().

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Josh Poimboeuf <[email protected]>
---
tools/objtool/check.c | 64 ++++++++++++++++++++++++++++----------------------
1 file changed, 36 insertions(+), 28 deletions(-)

--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1935,6 +1935,41 @@ static int validate_sibling_call(struct
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
@@ -2050,34 +2085,7 @@ static int validate_branch(struct objtoo
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:

2020-03-25 08:39:35

by Miroslav Benes

Subject: Re: [PATCH v3 01/26] objtool: Introduce validate_return()

On Tue, 24 Mar 2020, Peter Zijlstra wrote:

> Trivial 'cleanup' to save one indentation level and match
> validate_call().
>
> Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
> Acked-by: Josh Poimboeuf <[email protected]>

Reviewed-by: Miroslav Benes <[email protected]>

M

2020-03-26 10:09:35

by tip-bot2 for Alexey Makhalov

Subject: [tip: core/objtool] objtool: Introduce validate_return()

The following commit has been merged into the core/objtool branch of tip:

Commit-ID: a92e92d1a749e9bae9828f34f632d56ac2c6d2c3
Gitweb: https://git.kernel.org/tip/a92e92d1a749e9bae9828f34f632d56ac2c6d2c3
Author: Peter Zijlstra <[email protected]>
AuthorDate: Tue, 10 Mar 2020 18:07:44 +01:00
Committer: Peter Zijlstra <[email protected]>
CommitterDate: Wed, 25 Mar 2020 18:28:27 +01:00

objtool: Introduce validate_return()

Trivial 'cleanup' to save one indentation level and match
validate_call().

Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Miroslav Benes <[email protected]>
Acked-by: Josh Poimboeuf <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
---
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 6b6178e..da17b5a 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: