liquidio: read sc->iq_no before release sc

The function lio_vf_rep_packet_sent_callback releases the occupation of
sc via octeon_free_soft_command. sc should not be used after that.
Unfortunately, sc->iq_no is read. To fix this, the patch stores sc->iq_no
into a local variable before releasing sc and then uses the local variable
instead of sc->iq_no.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
index ea9859e028d4..de61060721c4 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_rep.c
@@ -349,13 +349,15 @@ lio_vf_rep_packet_sent_callback(struct octeon_device *oct,
         struct octeon_soft_command *sc = (struct octeon_soft_command *)buf;
         struct sk_buff *skb = sc->ctxptr;
         struct net_device *ndev = skb->dev;
+        u32 iq_no;
 
         dma_unmap_single(&oct->pci_dev->dev, sc->dmadptr,
                          sc->datasize, DMA_TO_DEVICE);
         dev_kfree_skb_any(skb);
+        iq_no = sc->iq_no;
         octeon_free_soft_command(oct, sc);
 
-        if (octnet_iq_is_full(oct, sc->iq_no))
+        if (octnet_iq_is_full(oct, iq_no))
                 return;
 
         if (netif_queue_stopped(ndev))