Re: [patch] Input: potential info leak in input_event_to_user()
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2011-09-23 07:30:04
Also in:
kernel-janitors
On Fri, Sep 23, 2011 at 09:22:07AM +0300, Dan Carpenter wrote:
Smatch has a new check for Rosenberg type information leaks where
structs are copied to the user with uninitialized stack data in them.
The issue here is that struct input_event_compat has a hole in it.
struct input_event_compat {
struct compat_timeval {
} time; /* 0 0 */
/* XXX 8 bytes hole, try to pack */
short unsigned int type; /* 8 2 */Hm, are you sure? 8-bytes is way too much. I'd expect type to be aligned on 2-byte boundary, at least on x86_64...
quoted hunk ↗ jump to hunk
Signed-off-by: Dan Carpenter <redacted>diff --git a/drivers/input/input-compat.c b/drivers/input/input-compat.c index e46a867..007850a 100644 --- a/drivers/input/input-compat.c +++ b/drivers/input/input-compat.c@@ -44,6 +44,8 @@ int input_event_to_user(char __user *buffer, if (INPUT_COMPAT_TEST) { struct input_event_compat compat_event; + memset(&compat_event, 0, sizeof(compat_event)); + compat_event.time.tv_sec = event->time.tv_sec; compat_event.time.tv_usec = event->time.tv_usec; compat_event.type = event->type;
-- Dmitry