From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:58010) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gor0x-0006sT-6m for qemu-devel@nongnu.org; Wed, 30 Jan 2019 09:38:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gor0w-0001Jl-Ab for qemu-devel@nongnu.org; Wed, 30 Jan 2019 09:38:55 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:49876) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gor0w-0001JB-2M for qemu-devel@nongnu.org; Wed, 30 Jan 2019 09:38:54 -0500 From: Liam Merwick Date: Wed, 30 Jan 2019 14:37:02 +0000 Message-Id: <1548859022-3969-3-git-send-email-liam.merwick@oracle.com> In-Reply-To: <1548859022-3969-1-git-send-email-liam.merwick@oracle.com> References: <1548859022-3969-1-git-send-email-liam.merwick@oracle.com> Subject: [Qemu-devel] [PATCH 2/2] usb: deal with potential Null pointer returned by usb_ep_get() List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: kraxel@redhat.com, qemu-devel@nongnu.org Cc: liam.merwick@oracle.com, Darren.Kenny@oracle.com, Mark.Kanda@oracle.com, ameya.more@oracle.com From: Liam Merwick usb_ep_get() can return a Null pointer in the (albeit unlikely) case that a NULL USBDevice is passed in via the 'dev' parameter. Before dereferencing the return value from usb_ep_get(), check its validity and use a default (invalid) value where needed. Reported by the Parfait static code analysis tool Signed-off-by: Liam Merwick Reviewed-by: Darren Kenny Reviewed-by: Mark Kanda Reviewed-by: Ameya More --- hw/usb/core.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/hw/usb/core.c b/hw/usb/core.c index 1aa0051b2b2d..9d46a4b41e99 100644 --- a/hw/usb/core.c +++ b/hw/usb/core.c @@ -733,19 +733,23 @@ struct USBEndpoint *usb_ep_get(USBDevice *dev, int pid, int ep) uint8_t usb_ep_get_type(USBDevice *dev, int pid, int ep) { struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); - return uep->type; + return uep ? uep->type : USB_ENDPOINT_XFER_INVALID; } void usb_ep_set_type(USBDevice *dev, int pid, int ep, uint8_t type) { struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); - uep->type = type; + if (uep) { + uep->type = type; + } } void usb_ep_set_ifnum(USBDevice *dev, int pid, int ep, uint8_t ifnum) { struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); - uep->ifnum = ifnum; + if (uep) { + uep->ifnum = ifnum; + } } void usb_ep_set_max_packet_size(USBDevice *dev, int pid, int ep, @@ -754,6 +758,10 @@ void usb_ep_set_max_packet_size(USBDevice *dev, int pid, int ep, struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); int size, microframes; + if (!uep) { + return; + } + size = raw & 0x7ff; switch ((raw >> 11) & 3) { case 1: @@ -774,6 +782,10 @@ void usb_ep_set_max_streams(USBDevice *dev, int pid, int ep, uint8_t raw) struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); int MaxStreams; + if (!uep) { + return; + } + MaxStreams = raw & 0x1f; if (MaxStreams) { uep->max_streams = 1 << MaxStreams; @@ -785,7 +797,9 @@ void usb_ep_set_max_streams(USBDevice *dev, int pid, int ep, uint8_t raw) void usb_ep_set_halted(USBDevice *dev, int pid, int ep, bool halted) { struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); - uep->halted = halted; + if (uep) { + uep->halted = halted; + } } USBPacket *usb_ep_find_packet_by_id(USBDevice *dev, int pid, int ep, @@ -794,6 +808,10 @@ USBPacket *usb_ep_find_packet_by_id(USBDevice *dev, int pid, int ep, struct USBEndpoint *uep = usb_ep_get(dev, pid, ep); USBPacket *p; + if (!uep) { + return NULL; + } + QTAILQ_FOREACH(p, &uep->queue, queue) { if (p->id == id) { return p; -- 1.8.3.1