From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41056) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bu8Wi-0002NJ-OO for qemu-devel@nongnu.org; Tue, 11 Oct 2016 21:40:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bu8We-0001dY-Qg for qemu-devel@nongnu.org; Tue, 11 Oct 2016 21:40:12 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:30837) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bu8We-0001Vr-6n for qemu-devel@nongnu.org; Tue, 11 Oct 2016 21:40:08 -0400 From: Huawei PSIRT References: <1476203260-5290-1-git-send-email-ppandit@redhat.com> In-Reply-To: <1476203260-5290-1-git-send-email-ppandit@redhat.com> Date: Wed, 12 Oct 2016 09:39:26 +0800 Message-ID: <001901d22429$79adad50$6d0907f0$@com> MIME-Version: 1.0 Content-Type: text/plain; charset="gb2312" Content-Transfer-Encoding: quoted-printable Content-Language: zh-cn Subject: Re: [Qemu-devel] [PATCH] char: serial: check divider value against baud base List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: ppandit@redhat.com, qemu-devel@nongnu.org Cc: mst@redhat.com, pbonzini@redhat.com, pjp@fedoraproject.org, yanghongke , Huawei PSIRT , "Wanglijun (PSIRT)" Dear, Thank you very much for your support. And will you assign a CVE-ID for = the issue? Best regards, Huawei PSIRT -----=D3=CA=BC=FE=D4=AD=BC=FE----- =B7=A2=BC=FE=C8=CB: P J P [mailto:ppandit@redhat.com]=20 =B7=A2=CB=CD=CA=B1=BC=E4: 2016=C4=EA10=D4=C212=C8=D5 0:28 =CA=D5=BC=FE=C8=CB: Qemu Developers =B3=AD=CB=CD: Michael S. Tsirkin; Paolo Bonzini; Huawei PSIRT; Prasad J = Pandit =D6=F7=CC=E2: [PATCH] char: serial: check divider value against baud = base From: Prasad J Pandit 16550A UART device uses an oscillator to generate frequencies (baud = base), which decide communication speed. This speed could be changed by = dividing it by a divider. If the divider is greater than the baud base, speed is set = to zero, leading to a divide by zero error. Add check to avoid it. Reported-by: Huawei PSIRT Signed-off-by: Prasad J Pandit --- hw/char/serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/char/serial.c b/hw/char/serial.c index 3442f47..f659bbd 100644 --- a/hw/char/serial.c +++ b/hw/char/serial.c @@ -153,7 +153,7 @@ static void serial_update_parameters(SerialState *s) int speed, parity, data_bits, stop_bits, frame_size; QEMUSerialSetParams ssp; =20 - if (s->divider =3D=3D 0) + if (s->divider =3D=3D 0 || s->divider > s->baudbase) return; =20 /* Start bit. */ -- 2.5.5