From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48830) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cdqex-00028t-5D for qemu-devel@nongnu.org; Tue, 14 Feb 2017 22:53:43 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cdqev-0008R3-Po for qemu-devel@nongnu.org; Tue, 14 Feb 2017 22:53:39 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34106) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cdqev-0008Qk-K2 for qemu-devel@nongnu.org; Tue, 14 Feb 2017 22:53:37 -0500 From: Jason Wang Date: Wed, 15 Feb 2017 11:53:21 +0800 Message-Id: <1487130802-27953-5-git-send-email-jasowang@redhat.com> In-Reply-To: <1487130802-27953-1-git-send-email-jasowang@redhat.com> References: <1487130802-27953-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PULL 4/5] net: imx: limit buffer descriptor count List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org Cc: qemu-devel@nongnu.org, Prasad J Pandit , Jason Wang From: Prasad J Pandit i.MX Fast Ethernet Controller uses buffer descriptors to manage data flow to/fro receive & transmit queues. While transmitting packets, it could continue to read buffer descriptors if a buffer descriptor has length of zero and has crafted values in bd.flags. Set an upper limit to number of buffer descriptors. Reported-by: Li Qiang Signed-off-by: Prasad J Pandit Signed-off-by: Jason Wang --- hw/net/imx_fec.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c index 50c7564..90e6ee3 100644 --- a/hw/net/imx_fec.c +++ b/hw/net/imx_fec.c @@ -55,6 +55,8 @@ } \ } while (0) +#define IMX_MAX_DESC 1024 + static const char *imx_default_reg_name(IMXFECState *s, uint32_t index) { static char tmp[20]; @@ -402,12 +404,12 @@ static void imx_eth_update(IMXFECState *s) static void imx_fec_do_tx(IMXFECState *s) { - int frame_size = 0; + int frame_size = 0, descnt = 0; uint8_t frame[ENET_MAX_FRAME_SIZE]; uint8_t *ptr = frame; uint32_t addr = s->tx_descriptor; - while (1) { + while (descnt++ < IMX_MAX_DESC) { IMXFECBufDesc bd; int len; @@ -453,12 +455,12 @@ static void imx_fec_do_tx(IMXFECState *s) static void imx_enet_do_tx(IMXFECState *s) { - int frame_size = 0; + int frame_size = 0, descnt = 0; uint8_t frame[ENET_MAX_FRAME_SIZE]; uint8_t *ptr = frame; uint32_t addr = s->tx_descriptor; - while (1) { + while (descnt++ < IMX_MAX_DESC) { IMXENETBufDesc bd; int len; -- 2.7.4