linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: akpm@linux-foundation.org, andreyknvl@google.com,
	aryabinin@virtuozzo.com, cai@lca.pw, dvyukov@google.com,
	elver@google.com, glider@google.com, linux-mm@kvack.org,
	mm-commits@vger.kernel.org, rong.a.chen@intel.com,
	stable@vger.kernel.org, torvalds@linux-foundation.org
Subject: [patch 06/11] kasan: disable branch tracing for core runtime
Date: Fri, 22 May 2020 22:22:59 -0700	[thread overview]
Message-ID: <20200523052259.86QThphG9%akpm@linux-foundation.org> (raw)
In-Reply-To: <20200522222217.ee14ad7eda7aab1e6697da6c@linux-foundation.org>

From: Marco Elver <elver@google.com>
Subject: kasan: disable branch tracing for core runtime

During early boot, while KASAN is not yet initialized, it is possible to
enter reporting code-path and end up in kasan_report().  While
uninitialized, the branch there prevents generating any reports, however,
under certain circumstances when branches are being traced
(TRACE_BRANCH_PROFILING), we may recurse deep enough to cause kernel
reboots without warning.

To prevent similar issues in future, we should disable branch tracing for
the core runtime.

[elver@google.com: remove duplicate DISABLE_BRANCH_PROFILING, per Qian Cai]
  Link: https://lore.kernel.org/lkml/20200517011732.GE24705@shao2-debian/
  Link: http://lkml.kernel.org/r/20200522075207.157349-1-elver@google.com
Link: http://lkml.kernel.org/r//20200517011732.GE24705@shao2-debian/
Link: http://lkml.kernel.org/r/20200519182459.87166-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Qian Cai <cai@lca.pw>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kasan/Makefile  |   16 ++++++++--------
 mm/kasan/generic.c |    1 -
 mm/kasan/tags.c    |    1 -
 3 files changed, 8 insertions(+), 10 deletions(-)

--- a/mm/kasan/generic.c~kasan-disable-branch-tracing-for-core-runtime
+++ a/mm/kasan/generic.c
@@ -15,7 +15,6 @@
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#define DISABLE_BRANCH_PROFILING
 
 #include <linux/export.h>
 #include <linux/interrupt.h>
--- a/mm/kasan/Makefile~kasan-disable-branch-tracing-for-core-runtime
+++ a/mm/kasan/Makefile
@@ -15,14 +15,14 @@ CFLAGS_REMOVE_tags_report.o = $(CC_FLAGS
 
 # Function splitter causes unnecessary splits in __asan_load1/__asan_store1
 # see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533
-CFLAGS_common.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_generic.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_generic_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_init.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_quarantine.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_tags.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
-CFLAGS_tags_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector)
+CFLAGS_common.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_generic.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_generic_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_init.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_quarantine.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_tags.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
+CFLAGS_tags_report.o := $(call cc-option, -fno-conserve-stack -fno-stack-protector) -DDISABLE_BRANCH_PROFILING
 
 obj-$(CONFIG_KASAN) := common.o init.o report.o
 obj-$(CONFIG_KASAN_GENERIC) += generic.o generic_report.o quarantine.o
--- a/mm/kasan/tags.c~kasan-disable-branch-tracing-for-core-runtime
+++ a/mm/kasan/tags.c
@@ -12,7 +12,6 @@
  */
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#define DISABLE_BRANCH_PROFILING
 
 #include <linux/export.h>
 #include <linux/interrupt.h>
_


  parent reply	other threads:[~2020-05-23  5:23 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-23  5:22 incoming Andrew Morton
2020-05-23  5:22 ` [patch 01/11] device-dax: don't leak kernel memory to user space after unloading kmem Andrew Morton
2020-05-23  5:22 ` [patch 02/11] x86: bitops: fix build regression Andrew Morton
2020-05-23  5:22 ` [patch 03/11] rapidio: fix an error in get_user_pages_fast() error handling Andrew Morton
2020-05-23  5:22 ` [patch 04/11] selftests/vm/.gitignore: add mremap_dontunmap Andrew Morton
2020-05-23  5:22 ` [patch 05/11] selftests/vm/write_to_hugetlbfs.c: fix unused variable warning Andrew Morton
2020-05-23  5:22 ` Andrew Morton [this message]
2020-05-23  5:23 ` [patch 07/11] sh: include linux/time_types.h for sockios Andrew Morton
2020-05-23  5:23 ` [patch 08/11] MAINTAINERS: update email address for Naoya Horiguchi Andrew Morton
2020-05-23  5:23 ` [patch 09/11] sparc32: use PUD rather than PGD to get PMD in srmmu_nocache_init() Andrew Morton
2020-05-23 19:01   ` Mike Rapoport
2020-05-23 19:10     ` Linus Torvalds
2020-05-23 19:57       ` Mike Rapoport
2020-05-23  5:23 ` [patch 10/11] z3fold: fix use-after-free when freeing handles Andrew Morton
2020-05-23  5:23 ` [patch 11/11] MAINTAINERS: add files related to kdump Andrew Morton
2020-05-25  5:10 ` mmotm 2020-05-24-22-09 uploaded Andrew Morton
2020-05-25 23:57 ` mmotm 2020-05-25-16-56 uploaded Andrew Morton
2020-05-26  3:49   ` mmotm 2020-05-25-16-56 uploaded (drm/nouveau) Randy Dunlap
2020-05-26  4:23     ` Dave Airlie
2020-05-26  4:31       ` Randy Dunlap
2020-05-26  6:56   ` mmotm 2020-05-25-16-56 uploaded (mtd/nand/raw/arasan-nand-controller) Randy Dunlap
2020-05-26 19:37     ` Miquel Raynal

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200523052259.86QThphG9%akpm@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=andreyknvl@google.com \
    --cc=aryabinin@virtuozzo.com \
    --cc=cai@lca.pw \
    --cc=dvyukov@google.com \
    --cc=elver@google.com \
    --cc=glider@google.com \
    --cc=linux-mm@kvack.org \
    --cc=mm-commits@vger.kernel.org \
    --cc=rong.a.chen@intel.com \
    --cc=stable@vger.kernel.org \
    --cc=torvalds@linux-foundation.org \
    --subject='Re: [patch 06/11] kasan: disable branch tracing for core runtime' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).