From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45235) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9gC7-0004rS-Op for qemu-devel@nongnu.org; Mon, 29 Jun 2015 17:02:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z9gBz-0007ww-HZ for qemu-devel@nongnu.org; Mon, 29 Jun 2015 17:02:23 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:43586) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z9gBz-0007w6-Bc for qemu-devel@nongnu.org; Mon, 29 Jun 2015 17:02:15 -0400 From: Konrad Rzeszutek Wilk Date: Mon, 29 Jun 2015 17:02:00 -0400 Message-Id: <1435611725-15161-4-git-send-email-konrad.wilk@oracle.com> In-Reply-To: <1435611725-15161-1-git-send-email-konrad.wilk@oracle.com> References: <1435611725-15161-1-git-send-email-konrad.wilk@oracle.com> Subject: [Qemu-devel] [PATCH RFC 1 3/8] xen/pt: Check if reg->init is past the reg->size List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: stefano.stabellini@eu.citrix.com, xen-devel@lists.xenproject.org, qemu-devel@nongnu.org Cc: Konrad Rzeszutek Wilk It should never happen, but in case it does we want to report. The code will only write up to reg->size so there is no runtime danger. Signed-off-by: Konrad Rzeszutek Wilk --- hw/xen/xen_pt_config_init.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/hw/xen/xen_pt_config_init.c b/hw/xen/xen_pt_config_init.c index 91c3a14..bc871c9 100644 --- a/hw/xen/xen_pt_config_init.c +++ b/hw/xen/xen_pt_config_init.c @@ -1901,9 +1901,13 @@ static int xen_pt_config_reg_init(XenPCIPassthroughState *s, } else val = data; + if (val & size_mask) { + XEN_PT_ERR(&s->dev,"Offset 0x%04x:0x%04u expands past register size(%d)!\n", + offset, val, reg->size); + } /* This could be just pci_set_long as we don't modify the bits - * past reg->size, but in case this routine is run in parallel - * we do not want to over-write other registers. */ + * past reg->size, but in case this routine is run in parallel or the + * init value is larger, we do not want to over-write registers. */ switch (reg->size) { case 1: pci_set_byte(s->dev.config + offset, (uint8_t)val); break; case 2: pci_set_word(s->dev.config + offset, (uint16_t)val); break; -- 2.1.0