From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from list by lists.gnu.org with archive (Exim 4.71) id 1XqK15-0004Sf-2X for mharc-qemu-trivial@gnu.org; Mon, 17 Nov 2014 05:58:43 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48541) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqK0z-0004J9-E2 for qemu-trivial@nongnu.org; Mon, 17 Nov 2014 05:58:42 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqK0u-0007RV-LR for qemu-trivial@nongnu.org; Mon, 17 Nov 2014 05:58:37 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51842) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqK0u-0007RR-Ca; Mon, 17 Nov 2014 05:58:32 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sAHAwIJh012259 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 17 Nov 2014 05:58:18 -0500 Received: from [10.36.112.46] (ovpn-112-46.ams2.redhat.com [10.36.112.46]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sAHAwDiG008987 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Mon, 17 Nov 2014 05:58:15 -0500 Message-ID: <5469D4C4.5090407@redhat.com> Date: Mon, 17 Nov 2014 11:58:12 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: arei.gonglei@huawei.com, qemu-devel@nongnu.org References: <1416046008-7880-1-git-send-email-arei.gonglei@huawei.com> <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> In-Reply-To: <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: weidong.huang@huawei.com, zhang.zhanghailiang@huawei.com, qemu-trivial@nongnu.org, mjt@tls.msk.ru, peter.huangpeng@huawei.com, Gerd Hoffmann Subject: Re: [Qemu-trivial] [PATCH 9/9] hcd-musb: fix dereference null return value X-BeenThere: qemu-trivial@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Nov 2014 10:58:42 -0000 On 15/11/2014 11:06, arei.gonglei@huawei.com wrote: > From: Gonglei > > Signed-off-by: Gonglei > --- > hw/usb/hcd-musb.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c > index 66bc61a..f2cb73c 100644 > --- a/hw/usb/hcd-musb.c > +++ b/hw/usb/hcd-musb.c > @@ -624,6 +624,10 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > > /* A wild guess on the FADDR semantics... */ > dev = usb_find_device(&s->port, ep->faddr[idx]); > + if (!dev) { > + TRACE("Do not find an usb device"); > + return; > + } > uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); > usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, > (dev->addr << 16) | (uep->nr << 8) | pid, false, true); > I think this patch is not the real fix. usb_ep_get and usb_handle_packet can deal with a NULL device, but we have to avoid dereferencing NULL pointers when building the id. Paolo diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c index 66bc61a..40809f6 100644 --- a/hw/usb/hcd-musb.c +++ b/hw/usb/hcd-musb.c @@ -608,6 +608,7 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, USBDevice *dev; USBEndpoint *uep; int idx = epnum && dir; + int id; int ttype; /* ep->type[0,1] contains: @@ -625,8 +626,11 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, /* A wild guess on the FADDR semantics... */ dev = usb_find_device(&s->port, ep->faddr[idx]); uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); - usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, - (dev->addr << 16) | (uep->nr << 8) | pid, false, true); + id = pid; + if (uep) { + id |= (dev->addr << 16) | (uep->nr << 8); + } + usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, id, false, true); usb_packet_addbuf(&ep->packey[dir].p, ep->buf[idx], len); ep->packey[dir].ep = ep; ep->packey[dir].dir = dir; From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48561) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqK19-0004cR-1S for qemu-devel@nongnu.org; Mon, 17 Nov 2014 05:58:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqK14-0007Sj-8E for qemu-devel@nongnu.org; Mon, 17 Nov 2014 05:58:46 -0500 Message-ID: <5469D4C4.5090407@redhat.com> Date: Mon, 17 Nov 2014 11:58:12 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1416046008-7880-1-git-send-email-arei.gonglei@huawei.com> <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> In-Reply-To: <1416046008-7880-10-git-send-email-arei.gonglei@huawei.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 9/9] hcd-musb: fix dereference null return value List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: arei.gonglei@huawei.com, qemu-devel@nongnu.org Cc: weidong.huang@huawei.com, zhang.zhanghailiang@huawei.com, qemu-trivial@nongnu.org, mjt@tls.msk.ru, peter.huangpeng@huawei.com, Gerd Hoffmann On 15/11/2014 11:06, arei.gonglei@huawei.com wrote: > From: Gonglei > > Signed-off-by: Gonglei > --- > hw/usb/hcd-musb.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c > index 66bc61a..f2cb73c 100644 > --- a/hw/usb/hcd-musb.c > +++ b/hw/usb/hcd-musb.c > @@ -624,6 +624,10 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, > > /* A wild guess on the FADDR semantics... */ > dev = usb_find_device(&s->port, ep->faddr[idx]); > + if (!dev) { > + TRACE("Do not find an usb device"); > + return; > + } > uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); > usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, > (dev->addr << 16) | (uep->nr << 8) | pid, false, true); > I think this patch is not the real fix. usb_ep_get and usb_handle_packet can deal with a NULL device, but we have to avoid dereferencing NULL pointers when building the id. Paolo diff --git a/hw/usb/hcd-musb.c b/hw/usb/hcd-musb.c index 66bc61a..40809f6 100644 --- a/hw/usb/hcd-musb.c +++ b/hw/usb/hcd-musb.c @@ -608,6 +608,7 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, USBDevice *dev; USBEndpoint *uep; int idx = epnum && dir; + int id; int ttype; /* ep->type[0,1] contains: @@ -625,8 +626,11 @@ static void musb_packet(MUSBState *s, MUSBEndPoint *ep, /* A wild guess on the FADDR semantics... */ dev = usb_find_device(&s->port, ep->faddr[idx]); uep = usb_ep_get(dev, pid, ep->type[idx] & 0xf); - usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, - (dev->addr << 16) | (uep->nr << 8) | pid, false, true); + id = pid; + if (uep) { + id |= (dev->addr << 16) | (uep->nr << 8); + } + usb_packet_setup(&ep->packey[dir].p, pid, uep, 0, id, false, true); usb_packet_addbuf(&ep->packey[dir].p, ep->buf[idx], len); ep->packey[dir].ep = ep; ep->packey[dir].dir = dir;