From 1f9296b51a26650916a2c4191268bb64057bdc5f Mon Sep 17 00:00:00 2001 From: Luiz Capitulino Date: Mon, 15 Sep 2014 12:00:11 -0400 Subject: [PATCH] virtio-balloon: fix integer overflow in memory stats feature 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 Reviewed-by: Eric Blake Reviewed-by: Markus Armbruster --- 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 2c30b3d8bd..b5cf7cacc0 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; }