[Qemu-commits] [qemu/qemu] 915976: hw/net/dp8393x: fix integer underflow in dp8393x_d...

[Paolo Bonzini]

  Branch: refs/heads/staging
  Home:   https://github.com/qemu/qemu
  Commit: 915976bd98a9286efe6f2e573cb4f1360603adf9
      
https://github.com/qemu/qemu/commit/915976bd98a9286efe6f2e573cb4f1360603adf9
  Author: Mauro Matteo Cascella <mcascell@redhat.com>
  Date:   2020-12-01 (Tue, 01 Dec 2020)

  Changed paths:
    M hw/net/dp8393x.c

  Log Message:
  -----------
  hw/net/dp8393x: fix integer underflow in dp8393x_do_transmit_packets()

An integer underflow could occur during packet transmission due to 'tx_len' not
being updated if SONIC_TFC register is set to zero. Check for negative 'tx_len'
when removing existing FCS.

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1899722
Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
Reported-by: Gaoning Pan <pgn@zju.edu.cn>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-id: 20201124092445.658647-1-mcascell@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>