[Qemu-devel] [PATCH for v2.6.0] net: imx: check buffer descriptor length

[P J P]

From: Prasad J Pandit <address@hidden>

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. Add check to avoid it.

Reported-by: Li Qiang <address@hidden>
Signed-off-by: Prasad J Pandit <address@hidden>
---
 hw/net/imx_fec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c
index e60e338..31870b0 100644
--- a/hw/net/imx_fec.c
+++ b/hw/net/imx_fec.c
@@ -276,7 +276,7 @@ static void imx_fec_do_tx(IMXFECState *s)
         imx_fec_read_bd(&bd, addr);
         FEC_PRINTF("tx_bd %x flags %04x len %d data %08x\n",
                    addr, bd.flags, bd.length, bd.data);
-        if ((bd.flags & FEC_BD_R) == 0) {
+        if (!bd.length || (bd.flags & FEC_BD_R) == 0) {
             /* Run out of descriptors to transmit.  */
             break;
         }
-- 
2.5.5