| From c2cb511634012344e3d0fe49a037a33b12d8a98a Mon Sep 17 00:00:00 2001 |
| From: Prasad J Pandit <pjp@fedoraproject.org> |
| Date: Wed, 11 Nov 2020 18:36:36 +0530 |
| Subject: [PATCH] hw/net/e1000e: advance desc_offset in case of null |
| descriptor |
| |
| While receiving packets via e1000e_write_packet_to_guest() routine, |
| 'desc_offset' is advanced only when RX descriptor is processed. And |
| RX descriptor is not processed if it has NULL buffer address. |
| This may lead to an infinite loop condition. Increament 'desc_offset' |
| to process next descriptor in the ring to avoid infinite loop. |
| |
| Reported-by: Cheol-woo Myung <330cjfdn@gmail.com> |
| Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org> |
| Signed-off-by: Jason Wang <jasowang@redhat.com> |
| |
| Upstream-Status: Backport |
| CVE: CVE-2020-28916 |
| [https://git.qemu.org/?p=qemu.git;a=commit;h=c2cb511634012344e3d0fe49a037a33b12d8a98a] |
| Signed-off-by: Li Wang <li.wang@windriver.com> |
| --- |
| hw/net/e1000e_core.c | 8 ++++---- |
| 1 file changed, 4 insertions(+), 4 deletions(-) |
| |
| diff --git a/hw/net/e1000e_core.c b/hw/net/e1000e_core.c |
| index bcd186c..d3e3cdc 100644 |
| --- a/hw/net/e1000e_core.c |
| +++ b/hw/net/e1000e_core.c |
| @@ -1596,13 +1596,13 @@ e1000e_write_packet_to_guest(E1000ECore *core, struct NetRxPkt *pkt, |
| (const char *) &fcs_pad, e1000x_fcs_len(core->mac)); |
| } |
| } |
| - desc_offset += desc_size; |
| - if (desc_offset >= total_size) { |
| - is_last = true; |
| - } |
| } else { /* as per intel docs; skip descriptors with null buf addr */ |
| trace_e1000e_rx_null_descriptor(); |
| } |
| + desc_offset += desc_size; |
| + if (desc_offset >= total_size) { |
| + is_last = true; |
| + } |
| |
| e1000e_write_rx_descr(core, desc, is_last ? core->rx_pkt : NULL, |
| rss_info, do_ps ? ps_hdr_len : 0, &bastate.written); |
| -- |
| 2.17.1 |
| |