From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46583) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XTtIR-0006vF-6L for qemu-devel@nongnu.org; Tue, 16 Sep 2014 10:00:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XTtII-0007dE-Vv for qemu-devel@nongnu.org; Tue, 16 Sep 2014 09:59:55 -0400 Date: Tue, 16 Sep 2014 18:02:54 +0300 From: "Michael S. Tsirkin" Message-ID: <20140916150254.GA12989@redhat.com> References: <20140916093950.4339b5b9@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140916093950.4339b5b9@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2] virtio-balloon: fix integer overflow in memory stats feature List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Luiz Capitulino Cc: armbru@redhat.com, qemu-devel , qemu-stable@nongnu.org On Tue, Sep 16, 2014 at 09:39:50AM -0400, Luiz Capitulino wrote: > When a QMP client changes the polling interval time by setting > the guest-stats-polling-interval property, the interval value > is stored and manipulated as an int64_t variable. > > However, the balloon_stats_change_timer() function, which is > used to set the actual timer with the interval value, takes > an int instead, causing an overflow for big interval values. > > This commit fix this bug by changing balloon_stats_change_timer() > to take an int64_t and also it limits the polling interval value > to UINT_MAX to avoid other kinds of overflow. > > Signed-off-by: Luiz Capitulino OK but pls remember to Cc qemu-stable on bugfixes. > --- > hw/virtio/virtio-balloon.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 2c30b3d..b5cf7ca 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -87,7 +87,7 @@ static void balloon_stats_destroy_timer(VirtIOBalloon *s) > } > } > > -static void balloon_stats_change_timer(VirtIOBalloon *s, int secs) > +static void balloon_stats_change_timer(VirtIOBalloon *s, int64_t secs) > { > timer_mod(s->stats_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + secs * 1000); > } > @@ -170,6 +170,11 @@ static void balloon_stats_set_poll_interval(Object *obj, struct Visitor *v, > return; > } > > + if (value > UINT_MAX) { > + error_setg(errp, "timer value is too big"); > + return; > + } > + > if (value == s->stats_poll_interval) { > return; > } > -- > 1.9.3 >