This is a note to let you know that I've just added the patch titled
tracing/perf: Avoid -Warray-bounds warning for __rel_loc macro
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tracing-perf-avoid-warray-bounds-warning-for-__rel_loc-macro.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c6d777acdf8f62d4ebaef0e5c6cd8fedbd6e8546 Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@xxxxxxxxxxxx>
Date: Tue, 25 Jan 2022 14:00:37 -0800
Subject: tracing/perf: Avoid -Warray-bounds warning for __rel_loc macro
From: Kees Cook <keescook@xxxxxxxxxxxx>
commit c6d777acdf8f62d4ebaef0e5c6cd8fedbd6e8546 upstream.
As done for trace_events.h, also fix the __rel_loc macro in perf.h,
which silences the -Warray-bounds warning:
In file included from ./include/linux/string.h:253,
from ./include/linux/bitmap.h:11,
from ./include/linux/cpumask.h:12,
from ./include/linux/mm_types_task.h:14,
from ./include/linux/mm_types.h:5,
from ./include/linux/buildid.h:5,
from ./include/linux/module.h:14,
from samples/trace_events/trace-events-sample.c:2:
In function '__fortify_strcpy',
inlined from 'perf_trace_foo_rel_loc' at samples/trace_events/./trace-events-sample.h:519:1:
./include/linux/fortify-string.h:47:33: warning: '__builtin_strcpy' offset 12 is out of the bounds [
0, 4] [-Warray-bounds]
47 | #define __underlying_strcpy __builtin_strcpy
| ^
./include/linux/fortify-string.h:445:24: note: in expansion of macro '__underlying_strcpy'
445 | return __underlying_strcpy(p, q);
| ^~~~~~~~~~~~~~~~~~~
Also make __data struct member a proper flexible array to avoid future
problems.
Link: https://lkml.kernel.org/r/20220125220037.2738923-1-keescook@xxxxxxxxxxxx
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Fixes: 55de2c0b5610c ("tracing: Add '__rel_loc' using trace event macros")
Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/trace/perf.h | 5 +++--
include/trace/trace_events.h | 2 +-
2 files changed, 4 insertions(+), 3 deletions(-)
--- a/include/trace/perf.h
+++ b/include/trace/perf.h
@@ -23,8 +23,9 @@
#undef __get_rel_dynamic_array
#define __get_rel_dynamic_array(field) \
- ((void *)(&__entry->__rel_loc_##field) + \
- sizeof(__entry->__rel_loc_##field) + \
+ ((void *)__entry + \
+ offsetof(typeof(*__entry), __rel_loc_##field) + \
+ sizeof(__entry->__rel_loc_##field) + \
(__entry->__rel_loc_##field & 0xffff))
#undef __get_rel_dynamic_array_len
--- a/include/trace/trace_events.h
+++ b/include/trace/trace_events.h
@@ -128,7 +128,7 @@ TRACE_MAKE_SYSTEM_STR();
struct trace_event_raw_##name { \
struct trace_entry ent; \
tstruct \
- char __data[0]; \
+ char __data[]; \
}; \
\
static struct trace_event_class event_class_##name;
Patches currently in stable-queue which might be from keescook@xxxxxxxxxxxx are
queue-5.15/stack-declare-randomize_-kstack_offset-to-fix-sparse.patch
queue-5.15/tracing-avoid-warray-bounds-warning-for-__rel_loc-ma.patch
queue-5.15/tracing-perf-avoid-warray-bounds-warning-for-__rel_loc-macro.patch
queue-5.15/kasan-test-silence-gcc-12-warnings.patch
queue-5.15/selftests-seccomp-fix-compile-warning-when-cc-clang.patch
