virtio-net: truncating packet
PATCH v3 1/1 virtio-net: truncating packet
virtio net attempts to peek into virtio queue to determine that we have enough space for the complete packet to fit. However, it fails to account for space consumed by virtio net header when it does this, under stress this results in a failure
with the message 'truncating packet'.
redhat bz 591494.
Signed-off-by Michael S. Tsirkin <[email protected]>
v2 was sent in error.
Now fixed whitespace for real.
--- hw/virtio-net.c | 15 +++++++++------ 1 files changed, 9 insertions(+), 6 deletions(-)
hw/virtio-net.c +9 -6
@@ -532,16 +532,17 @@ static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_if (!virtio_net_can_receive (&n->nic->nc))return -1 ; -if (!virtio_net_has_buffers (n, size)) +/* hdr_len refers to the header we supply to the guest */ + hdr_len = n->mergeable_rx_bufs ? +sizeof (struct virtio_net_hdr_mrg_rxbuf ) :sizeof (struct virtio_net_hdr ); + + +if (!virtio_net_has_buffers (n, size + hdr_len))return 0 ;if (!receive_filter (n, buf, size))return size; -/* hdr_len refers to the header we supply to the guest */ - hdr_len = n->mergeable_rx_bufs ? -sizeof (struct virtio_net_hdr_mrg_rxbuf ) :sizeof (struct virtio_net_hdr ); - offset = i =0 ;while (offset < size) {
@@ -555,7 +556,9 @@ static ssize_t virtio_net_receive(VLANClientState *nc, const uint8_t *buf, size_ virtqueue_pop(n->rx_vq, &elem) == 0) {if (i ==0 )return -1 ; -fprintf (stderr,"virtio-net truncating packet\n" ); +fprintf (stderr,"virtio-net truncating packet: " +"offset %zd, size %zd, hdr_len %zd\n" , + offset, size, hdr_len);exit (1 ); }
Signature · 1 line
1.7.1.12.g42b7f