debian/patches/extra/0002-hw-net-net_tx_pkt-fix-assertion-failure-in-net_tx_pk.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Mauro Matteo Cascella <mcascell@redhat.com>
   3 Date: Sat, 1 Aug 2020 18:42:38 +0200
   4 Subject: [PATCH] hw/net/net_tx_pkt: fix assertion failure in
   5  net_tx_pkt_add_raw_fragment()
   6
   7 An assertion failure issue was found in the code that processes network packets
   8 while adding data fragments into the packet context. It could be abused by a
   9 malicious guest to abort the QEMU process on the host. This patch replaces the
  10 affected assert() with a conditional statement, returning false if the current
  11 data fragment exceeds max_raw_frags.
  12
  13 Reported-by: Alexander Bulekov <alxndr@bu.edu>
  14 Reported-by: Ziming Zhang <ezrakiez@gmail.com>
  15 Reviewed-by: Dmitry Fleytman <dmitry.fleytman@gmail.com>
  16 Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
  17 Signed-off-by: Jason Wang <jasowang@redhat.com>
  18 (cherry picked from commit 035e69b063835a5fd23cacabd63690a3d84532a8)
  19 Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>
  20 ---
  21  hw/net/net_tx_pkt.c | 5 ++++-
  22  1 file changed, 4 insertions(+), 1 deletion(-)
  23
  24 diff --git a/hw/net/net_tx_pkt.c b/hw/net/net_tx_pkt.c
  25 index 162f802dd7..54d4c3bbd0 100644
  26 --- a/hw/net/net_tx_pkt.c
  27 +++ b/hw/net/net_tx_pkt.c
  28 @@ -379,7 +379,10 @@ bool net_tx_pkt_add_raw_fragment(struct NetTxPkt *pkt, hwaddr pa,
  29      hwaddr mapped_len = 0;
  30      struct iovec *ventry;
  31      assert(pkt);
  32 -    assert(pkt->max_raw_frags > pkt->raw_frags);
  33 +
  34 +    if (pkt->raw_frags >= pkt->max_raw_frags) {
  35 +        return false;
  36 +    }
  37
  38      if (!len) {
  39          return true;
  40 --
  41 2.20.1
  42