target/linux/layerscape/patches-5.4/809-jailhouse-0012-ivshmem-net-fill-in-and-check-used-descriptor-chain-.patch

   1 From ec72823546e39cd486360f44db16cf47f7e8f59e Mon Sep 17 00:00:00 2001
   2 From: Henning Schild <henning.schild@siemens.com>
   3 Date: Mon, 18 Sep 2017 18:02:08 +0200
   4 Subject: [PATCH] ivshmem-net: fill in and check used descriptor chain len
   5
   6 We are using chains of len==1 make that explicit and expect that from
   7 the remote.
   8
   9 Signed-off-by: Henning Schild <henning.schild@siemens.com>
  10 Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
  11 (cherry picked from commit f958c360044184f58605815d428b83fe4329cafd)
  12 ---
  13  drivers/net/ivshmem-net.c | 14 ++++++++------
  14  1 file changed, 8 insertions(+), 6 deletions(-)
  15
  16 --- a/drivers/net/ivshmem-net.c
  17 +++ b/drivers/net/ivshmem-net.c
  18 @@ -335,10 +335,10 @@ static void ivshm_net_tx_clean(struct ne
  19  {
  20         struct ivshm_net *in = netdev_priv(ndev);
  21         struct ivshm_net_queue *tx = &in->tx;
  22 +       struct vring_used_elem *used;
  23         struct vring *vr = &tx->vr;
  24         struct vring_desc *desc;
  25         struct vring_desc *fdesc;
  26 -       unsigned int used;
  27         unsigned int num;
  28         u16 used_idx;
  29         u16 last;
  30 @@ -358,13 +358,14 @@ static void ivshm_net_tx_clean(struct ne
  31                 u32 len;
  32                 u32 tail;
  33
  34 -               used = vr->used->ring[last & (vr->num - 1)].id;
  35 -               if (used >= vr->num) {
  36 -                       netdev_err(ndev, "invalid tx used %d\n", used);
  37 +               used = vr->used->ring + (last % vr->num);
  38 +               if (used->id >= vr->num || used->len != 1) {
  39 +                       netdev_err(ndev, "invalid tx used->id %d ->len %d\n",
  40 +                                  used->id, used->len);
  41                         break;
  42                 }
  43
  44 -               desc = &vr->desc[used];
  45 +               desc = &vr->desc[used->id];
  46
  47                 data = ivshm_net_desc_data(in, &in->tx, desc, &len);
  48                 if (!data) {
  49 @@ -383,7 +384,7 @@ static void ivshm_net_tx_clean(struct ne
  50                 else
  51                         desc->next = fhead;
  52
  53 -               fhead = used;
  54 +               fhead = used->id;
  55                 last++;
  56                 num++;
  57         }
  58 @@ -433,6 +434,7 @@ static void ivshm_net_rx_finish(struct i
  59
  60         used = rx->last_used_idx++ & (vr->num - 1);
  61         vr->used->ring[used].id = desc_id;
  62 +       vr->used->ring[used].len = 1;
  63
  64         virt_store_release(&vr->used->idx, rx->last_used_idx);
  65  }