Re: [ 030/143] proc connector: fix info leaks

Willy Tarreau
2014-05-12T08:57:13Z

On Mon, May 12, 2014 at 10:51:31AM +0200, Mathias Krause wrote:
> On 12 May 2014 02:32, Willy Tarreau <w@1wt.eu> wrote:
> > 2.6.32-longterm review patch. If anyone has any objections, please let me know.
> >
> > ------------------
> >
> > From: Mathias Krause <minipli@googlemail.com>
> >
> > [ Upstream commit e727ca82e0e9616ab4844301e6bae60ca7327682 ]
> >
> > Initialize event_data for all possible message types to prevent leaking
> > kernel stack contents to userland (up to 20 bytes). Also set the flags
> > member of the connector message to 0 to prevent leaking two more stack
> > bytes this way.
> >
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Mathias Krause <minipli@googlemail.com>
> > Signed-off-by: David S. Miller <davem@davemloft.net>
> > Signed-off-by: Willy Tarreau <w@1wt.eu>
> > ---
> > drivers/connector/cn_proc.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
> > index 6069790..3a2587a 100644
> > --- a/drivers/connector/cn_proc.c
> > +++ b/drivers/connector/cn_proc.c
> > [...]
> > module_init(cn_proc_init);
> > + memset(&ev->event_data, 0, sizeof(ev->event_data));
> > + msg->flags = 0; /* not used */
>
> That last hunk looks bogus. Probably the source of Christoph's compile error.

Thank you guys, I'll check. I don't know why I didn't see them on an
allmodconfig build.

Willy