Commit 34e29ce7 authored by Prasad J Pandit's avatar Prasad J Pandit Committed by Jason Wang
Browse files

net: pcnet: check rx/tx descriptor ring length 



The AMD PC-Net II emulator has set of control and status(CSR)
registers. Of these, CSR76 and CSR78 hold receive and transmit
descriptor ring length respectively. This ring length could range
from 1 to 65535. Setting ring length to zero leads to an infinite
loop in pcnet_rdra_addr() or pcnet_transmit(). Add check to avoid it.

Reported-by: default avatarLi Qiang <liqiang6-s@360.cn>
Signed-off-by: default avatarPrasad J Pandit <pjp@fedoraproject.org>
Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
parent ede0cbeb

hw/net/pcnet.c

+3 −0
Original line number Diff line number Diff line
@@ -1429,8 +1429,11 @@ static void pcnet_csr_writew(PCNetState *s, uint32_t rap, uint32_t new_value) 
    case 47: /* POLLINT */

    case 72:

    case 74:

        break;

    case 76: /* RCVRL */

    case 78: /* XMTRL */

        val = (val > 0) ? val : 512;

        break;

    case 112:

       if (CSR_STOP(s) || CSR_SPND(s))

           break;