From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51509) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ai3dp-0001j3-97 for qemu-devel@nongnu.org; Mon, 21 Mar 2016 13:29:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ai3dl-0000wH-Vd for qemu-devel@nongnu.org; Mon, 21 Mar 2016 13:29:21 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:58272) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ai3dl-0000vj-Nq for qemu-devel@nongnu.org; Mon, 21 Mar 2016 13:29:17 -0400 Received: from localhost by e33.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 21 Mar 2016 11:29:17 -0600 From: Michael Roth Date: Mon, 21 Mar 2016 12:28:14 -0500 Message-Id: <1458581313-19045-17-git-send-email-mdroth@linux.vnet.ibm.com> In-Reply-To: <1458581313-19045-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1458581313-19045-1-git-send-email-mdroth@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 16/35] net: ne2000: check ring buffer control registers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Michael Roth , Jason Wang , qemu-stable@nongnu.org, Prasad J Pandit From: Prasad J Pandit Ne2000 NIC uses ring buffer of NE2000_MEM_SIZE(49152) bytes to process network packets. Registers PSTART & PSTOP define ring buffer size & location. Setting these registers to invalid values could lead to infinite loop or OOB r/w access issues. Add check to avoid it. Reported-by: Yang Hongke Tested-by: Yang Hongke Signed-off-by: Prasad J Pandit Signed-off-by: Jason Wang (cherry picked from commit 415ab35a441eca767d033a2702223e785b9d5190) Signed-off-by: Michael Roth --- hw/net/ne2000.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c index 010f9ef..84a7263 100644 --- a/hw/net/ne2000.c +++ b/hw/net/ne2000.c @@ -154,6 +154,10 @@ static int ne2000_buffer_full(NE2000State *s) { int avail, index, boundary; + if (s->stop <= s->start) { + return 1; + } + index = s->curpag << 8; boundary = s->boundary << 8; if (index < boundary) -- 1.9.1