Messages in this thread | | | Date | Mon, 8 Jul 2013 06:09:50 -0700 | Subject | Re: [PATCH 1/4] lkdtm: fix stack protector trigger | From | Kees Cook <> |
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Hi,
I'd like to get this series added to lkdtm. Can someone take a moment to review or ack them?
Thanks,
-Kees
On Sat, Jun 22, 2013 at 11:37 AM, Kees Cook <keescook@chromium.org> wrote: > The -fstack-protector compiler flag will only build stack protections if > a character array is seen. Additionally, the offset to the saved > instruction pointer changes based on architecture, so stomp much harder > (64 bytes) when corrupting the stack. > > Signed-off-by: Kees Cook <keescook@chromium.org> > --- > drivers/misc/lkdtm.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/misc/lkdtm.c b/drivers/misc/lkdtm.c > index 08aad69..adb6bde 100644 > --- a/drivers/misc/lkdtm.c > +++ b/drivers/misc/lkdtm.c > @@ -295,10 +295,10 @@ static void lkdtm_do_action(enum ctype which) > (void) recursive_loop(0); > break; > case CT_CORRUPT_STACK: { > - volatile u32 data[8]; > - volatile u32 *p = data; > + /* Make sure the compiler creates and uses an 8 char array. */ > + volatile char data[8]; > > - p[12] = 0x12345678; > + memset((void *)data, 0, 64); > break; > } > case CT_UNALIGNED_LOAD_STORE_WRITE: { > -- > 1.7.9.5 >
-- Kees Cook Chrome OS Security
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