debian/patches/extra/CVE-2016-7909-net-pcnet-check-rx-tx-descriptor-ring-length.patch

   1 From ed825b783750cbe88aa67bbe83cf662082828efa Mon Sep 17 00:00:00 2001
   2 From: Prasad J Pandit <pjp@fedoraproject.org>
   3 Date: Fri, 30 Sep 2016 00:27:33 +0530
   4 Subject: [PATCH 7/7] net: pcnet: check rx/tx descriptor ring length
   5
   6 The AMD PC-Net II emulator has set of control and status(CSR)
   7 registers. Of these, CSR76 and CSR78 hold receive and transmit
   8 descriptor ring length respectively. This ring length could range
   9 from 1 to 65535. Setting ring length to zero leads to an infinite
  10 loop in pcnet_rdra_addr. Add check to avoid it.
  11
  12 Reported-by: Li Qiang <liqiang6-s@360.cn>
  13 Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
  14 ---
  15  hw/net/pcnet.c | 3 +++
  16  1 file changed, 3 insertions(+)
  17
  18 diff --git a/hw/net/pcnet.c b/hw/net/pcnet.c
  19 index 198a01f..3078de8 100644
  20 --- a/hw/net/pcnet.c
  21 +++ b/hw/net/pcnet.c
  22 @@ -1429,8 +1429,11 @@ static void pcnet_csr_writew(PCNetState *s, uint32_t rap, uint32_t new_value)
  23      case 47: /* POLLINT */
  24      case 72:
  25      case 74:
  26 +        break;
  27      case 76: /* RCVRL */
  28      case 78: /* XMTRL */
  29 +        val = (val > 0) ? val : 512;
  30 +        break;
  31      case 112:
  32         if (CSR_STOP(s) || CSR_SPND(s))
  33             break;
  34 --
  35 2.1.4
  36