Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging

# gpg: Signature made Mon 22 Mar 2021 09:35:08 GMT
# gpg:                using RSA key EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  net/eth: Add an assert() and invert if() statement to simplify code
  net/eth: Read ip6_ext_hdr_routing buffer before accessing it
  net/eth: Check iovec has enough data earlier
  net/eth: Check size earlier in _eth_get_rss_ex_dst_addr()
  net/eth: Better describe _eth_get_rss_ex_dst_addr's offset argument
  net/eth: Simplify _eth_get_rss_ex_dst_addr()
  net/eth: Use correct in6_address offset in _eth_get_rss_ex_dst_addr()
  net/colo-compare.c: Optimize removal of secondary packet
  net/colo-compare.c: Fix memory leak for non-tcp packet
  hw/net: virtio-net: Initialize nc->do_not_pad to true
  net: Pad short frames to minimum size before sending from SLiRP/TAP
  net: Add a 'do_not_pad" to NetClientState
  net: eth: Add a helper to pad a short Ethernet frame

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/net/tap.c b/net/tap.c
index 12a08d54fe..d6d8456188 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -32,6 +32,7 @@
 #include <sys/socket.h>
 #include <net/if.h>
 
+#include "net/eth.h"
 #include "net/net.h"
 #include "clients.h"
 #include "monitor/monitor.h"
@@ -189,6 +190,8 @@ static void tap_send(void *opaque)
 
     while (true) {
         uint8_t *buf = s->buf;
+        uint8_t min_pkt[ETH_ZLEN];
+        size_t min_pktsz = sizeof(min_pkt);
 
         size = tap_read_packet(s->fd, s->buf, sizeof(s->buf));
         if (size <= 0) {
@@ -200,6 +203,13 @@ static void tap_send(void *opaque)
             size -= s->host_vnet_hdr_len;
         }
 
+        if (!s->nc.peer->do_not_pad) {
+            if (eth_pad_short_frame(min_pkt, &min_pktsz, buf, size)) {
+                buf = min_pkt;
+                size = min_pktsz;
+            }
+        }
+
         size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed);
         if (size == 0) {
             tap_read_poll(s, false);