RDMA/iw_cxgb4: Avoid freeing skb twice in arp failure case

BugLink: https://bugs.launchpad.net/bugs/1853519
[ Upstream commit d4934f45693651ea15357dd6c7c36be28b6da884 ]

_put_ep_safe() and _put_pass_ep_safe() free the skb before it is freed by
process_work(). fix double free by freeing the skb only in process_work().

Fixes: 1dad0ebeea1c ("iw_cxgb4: Avoid touch after free error in ARP failure handlers")
Link: https://lore.kernel.org/r/1572006880-5800-1-git-send-email-bharat@chelsio.com
Signed-off-by: Dakshaja Uppalapati <dakshaja@chelsio.com>
Signed-off-by: Potnuri Bharat Teja <bharat@chelsio.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 94399885eb0d9a942b5eb9478a07f23943014bea..dae073a2579b56307df2cb04e60727a0fc751986 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -493,7 +493,6 @@ static int _put_ep_safe(struct c4iw_dev *dev, struct sk_buff *skb)
 
        ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
        release_ep_resources(ep);
-       kfree_skb(skb);
        return 0;
 }
 
@@ -504,7 +503,6 @@ static int _put_pass_ep_safe(struct c4iw_dev *dev, struct sk_buff *skb)
        ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
        c4iw_put_ep(&ep->parent_ep->com);
        release_ep_resources(ep);
-       kfree_skb(skb);
        return 0;
 }