Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Fix BUG when decrypting empty packets in mac80211, from Ronald Wahl.

 2) nf_nat_range is not fully initialized and this is copied back to
    userspace, from Daniel Borkmann.

 3) Fix read past end of b uffer in netfilter ipset, also from Dan
    Carpenter.

 4) Signed integer overflow in ipv4 address mask creation helper
    inet_make_mask(), from Vincent BENAYOUN.

 5) VXLAN, be2net, mlx4_en, and qlcnic need ->ndo_gso_check() methods to
    properly describe the device's capabilities, from Joe Stringer.

 6) Fix memory leaks and checksum miscalculations in openvswitch, from
    Pravin B SHelar and Jesse Gross.

 7) FIB rules passes back ambiguous error code for unreachable routes,
    making behavior confusing for userspace.  Fix from Panu Matilainen.

 8) ieee802154fake_probe() doesn't release resources properly on error,
    from Alexey Khoroshilov.

 9) Fix skb_over_panic in add_grhead(), from Daniel Borkmann.

10) Fix access of stale slave pointers in bonding code, from Nikolay
    Aleksandrov.

11) Fix stack info leak in PPP pptp code, from Mathias Krause.

12) Cure locking bug in IPX stack, from Jiri Bohac.

13) Revert SKB fclone memory freeing optimization that is racey and can
    allow accesses to freed up memory, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (71 commits)
  tcp: Restore RFC5961-compliant behavior for SYN packets
  net: Revert "net: avoid one atomic operation in skb_clone()"
  virtio-net: validate features during probe
  cxgb4 : Fix DCB priority groups being returned in wrong order
  ipx: fix locking regression in ipx_sendmsg and ipx_recvmsg
  openvswitch: Don't validate IPv6 label masks.
  pptp: fix stack info leak in pptp_getname()
  brcmfmac: don't include linux/unaligned/access_ok.h
  cxgb4i : Don't block unload/cxgb4 unload when remote closes TCP connection
  ipv6: delete protocol and unregister rtnetlink when cleanup
  net/mlx4_en: Add VXLAN ndo calls to the PF net device ops too
  bonding: fix curr_active_slave/carrier with loadbalance arp monitoring
  mac80211: minstrel_ht: fix a crash in rate sorting
  vxlan: Inline vxlan_gso_check().
  can: m_can: update to support CAN FD features
  can: m_can: fix incorrect error messages
  can: m_can: add missing delay after setting CCCR_INIT bit
  can: m_can: fix not set can_dlc for remote frame
  can: m_can: fix possible sleep in napi poll
  can: m_can: add missing message RAM initialization
  ...

1 files changed, 6 insertions, 17 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index c16615bfb61e..32e31c299631 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -552,20 +552,13 @@ static void kfree_skbmem(struct sk_buff *skb)
         case SKB_FCLONE_CLONE:
                 fclones = container_of(skb, struct sk_buff_fclones, skb2);
 
-                /* Warning : We must perform the atomic_dec_and_test() before
-                 * setting skb->fclone back to SKB_FCLONE_FREE, otherwise
-                 * skb_clone() could set clone_ref to 2 before our decrement.
-                 * Anyway, if we are going to free the structure, no need to
-                 * rewrite skb->fclone.
+                /* The clone portion is available for
+                 * fast-cloning again.
                  */
-                if (atomic_dec_and_test(&fclones->fclone_ref)) {
+                skb->fclone = SKB_FCLONE_FREE;
+
+                if (atomic_dec_and_test(&fclones->fclone_ref))
                         kmem_cache_free(skbuff_fclone_cache, fclones);
-                } else {
-                        /* The clone portion is available for
-                         * fast-cloning again.
-                         */
-                        skb->fclone = SKB_FCLONE_FREE;
-                }
                 break;
         }
 }
@@ -887,11 +880,7 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
         if (skb->fclone == SKB_FCLONE_ORIG &&
             n->fclone == SKB_FCLONE_FREE) {
                 n->fclone = SKB_FCLONE_CLONE;
-                /* As our fastclone was free, clone_ref must be 1 at this point.
-                 * We could use atomic_inc() here, but it is faster
-                 * to set the final value.
-                 */
-                atomic_set(&fclones->fclone_ref, 2);
+                atomic_inc(&fclones->fclone_ref);
         } else {
                 if (skb_pfmemalloc(skb))
                         gfp_mask |= __GFP_MEMALLOC;