From: Prasad J Pandit Date: Thu, 2 Feb 2017 16:16:24 +0530 Subject: [PATCH] net: imx: limit buffer descriptor count 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 (cherry picked from commit 81f17e0d435c3db3a3e67e0d32ebf9c98973211f) --- 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 1c415ab3b1..6b42c10d96 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;