From: Kees Cook <keescook@chromium.org>
To: kernel-hardening@lists.openwall.com
Cc: Kees Cook <keescook@chromium.org>, Arnd Bergmann <arnd@arndb.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Andrew Morton <akpm@linux-foundation.org>,
"David S. Miller" <davem@davemloft.net>,
Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
Jiri Slaby <jslaby@suse.cz>, Guenter Roeck <linux@roeck-us.net>,
linux-kernel@vger.kernel.org
Subject: [PATCH 5/5] lkdtm: split atomic test into over and underflow
Date: Tue, 7 Jun 2016 14:57:08 -0700 [thread overview]
Message-ID: <1465336628-18219-6-git-send-email-keescook@chromium.org> (raw)
In-Reply-To: <1465336628-18219-1-git-send-email-keescook@chromium.org>
Each direction of the atomic wrapping should be individually testable.
Signed-off-by: Kees Cook <keescook@chromium.org>
---
drivers/misc/lkdtm_core.c | 26 ++++++++++++++++++++------
1 file changed, 20 insertions(+), 6 deletions(-)
diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c
index f212f865f9c6..b5a544f2b645 100644
--- a/drivers/misc/lkdtm_core.c
+++ b/drivers/misc/lkdtm_core.c
@@ -111,7 +111,8 @@ enum ctype {
CT_WRITE_RO,
CT_WRITE_RO_AFTER_INIT,
CT_WRITE_KERN,
- CT_WRAP_ATOMIC,
+ CT_ATOMIC_UNDERFLOW,
+ CT_ATOMIC_OVERFLOW,
CT_USERCOPY_HEAP_SIZE_TO,
CT_USERCOPY_HEAP_SIZE_FROM,
CT_USERCOPY_HEAP_FLAG_TO,
@@ -160,7 +161,8 @@ static char* cp_type[] = {
"WRITE_RO",
"WRITE_RO_AFTER_INIT",
"WRITE_KERN",
- "WRAP_ATOMIC",
+ "ATOMIC_UNDERFLOW",
+ "ATOMIC_OVERFLOW",
"USERCOPY_HEAP_SIZE_TO",
"USERCOPY_HEAP_SIZE_FROM",
"USERCOPY_HEAP_FLAG_TO",
@@ -894,13 +896,25 @@ static void lkdtm_do_action(enum ctype which)
do_overwritten();
break;
}
- case CT_WRAP_ATOMIC: {
+ case CT_ATOMIC_UNDERFLOW: {
atomic_t under = ATOMIC_INIT(INT_MIN);
- atomic_t over = ATOMIC_INIT(INT_MAX);
- pr_info("attempting atomic underflow\n");
+ pr_info("attempting good atomic increment\n");
+ atomic_inc(&under);
+ atomic_dec(&under);
+
+ pr_info("attempting bad atomic underflow\n");
atomic_dec(&under);
- pr_info("attempting atomic overflow\n");
+ break;
+ }
+ case CT_ATOMIC_OVERFLOW: {
+ atomic_t over = ATOMIC_INIT(INT_MAX);
+
+ pr_info("attempting good atomic decrement\n");
+ atomic_dec(&over);
+ atomic_inc(&over);
+
+ pr_info("attempting bad atomic overflow\n");
atomic_inc(&over);
return;
--
2.7.4
prev parent reply other threads:[~2016-06-07 21:57 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-07 21:57 [PATCH 0/5] lkdtm: add usercopy and rodata, fix atomic Kees Cook
2016-06-07 21:57 ` [PATCH 1/5] lkdtm: split build into multiple source files Kees Cook
2016-06-07 21:57 ` [PATCH 2/5] lkdtm: clean up after rename Kees Cook
2016-06-07 21:57 ` [PATCH 3/5] lkdtm: add function for testing .rodata section Kees Cook
2016-06-08 1:02 ` Laura Abbott
2016-06-08 15:46 ` Kees Cook
2016-06-08 16:15 ` Laura Abbott
2016-06-08 21:26 ` Kees Cook
2016-06-10 1:14 ` Laura Abbott
[not found] ` <87h9b4oebf.fsf@concordia.ellerman.id.au>
2016-08-01 19:45 ` Linker segfault on powerpc when CONFIG_LKDTM=y (was Re: [kernel-hardening] [PATCH 3/5] lkdtm: add function for testing .rodata section) Kees Cook
2016-08-02 3:12 ` [kernel-hardening] " Michael Ellerman
2016-08-02 19:12 ` Kees Cook
2016-08-03 4:46 ` Michael Ellerman
2016-06-07 21:57 ` [PATCH 4/5] lkdtm: add usercopy tests Kees Cook
2016-06-07 23:36 ` kbuild test robot
2016-06-08 0:07 ` kbuild test robot
2016-06-07 21:57 ` Kees Cook [this message]
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