From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47117) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XTtL1-0008V7-1Z for qemu-devel@nongnu.org; Tue, 16 Sep 2014 10:02:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XTtKu-0008TJ-Tp for qemu-devel@nongnu.org; Tue, 16 Sep 2014 10:02:34 -0400 Date: Tue, 16 Sep 2014 10:02:21 -0400 From: Luiz Capitulino Message-ID: <20140916100221.70999af3@redhat.com> In-Reply-To: <20140916150254.GA12989@redhat.com> References: <20140916093950.4339b5b9@redhat.com> <20140916150254.GA12989@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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: "Michael S. Tsirkin" Cc: armbru@redhat.com, qemu-devel , qemu-stable@nongnu.org On Tue, 16 Sep 2014 18:02:54 +0300 "Michael S. Tsirkin" wrote: > 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. I did. > > > --- > > > 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 > > >