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

Pull networking fixes from David Miller:

 1) Prevent index integer overflow in ptr_ring, from Jason Wang.

 2) Program mvpp2 multicast filter properly, from Mikulas Patocka.

 3) The bridge brport attribute file is write only and doesn't have a
    ->show() method, don't blindly invoke it. From Xin Long.

 4) Inverted mask used in genphy_setup_forced(), from Ingo van Lil.

 5) Fix multiple definition issue with if_ether.h UAPI header, from
    Hauke Mehrtens.

 6) Fix GFP_KERNEL usage in atomic in RDS protocol code, from Sowmini
    Varadhan.

 7) Revert XDP redirect support from thunderx driver, it is not
    implemented properly. From Jesper Dangaard Brouer.

 8) Fix missing RTNL protection across some tipc operations, from Ying
    Xue.

 9) Return the correct IV bytes in the TLS getsockopt code, from Boris
    Pismenny.

10) Take tclassid into consideration properly when doing FIB rule
    matching. From Stefano Brivio.

11) cxgb4 device needs more PCI VPD quirks, from Casey Leedom.

12) TUN driver doesn't align frags properly, and we can end up doing
    unaligned atomics on misaligned metadata. From Eric Dumazet.

13) Fix various crashes found using DEBUG_PREEMPT in rmnet driver, from
    Subash Abhinov Kasiviswanathan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (56 commits)
  tg3: APE heartbeat changes
  mlxsw: spectrum_router: Do not unconditionally clear route offload indication
  net: qualcomm: rmnet: Fix possible null dereference in command processing
  net: qualcomm: rmnet: Fix warning seen with 64 bit stats
  net: qualcomm: rmnet: Fix crash on real dev unregistration
  sctp: remove the left unnecessary check for chunk in sctp_renege_events
  rxrpc: Work around usercopy check
  tun: fix tun_napi_alloc_frags() frag allocator
  udplite: fix partial checksum initialization
  skbuff: Fix comment mis-spelling.
  dn_getsockoptdecnet: move nf_{get/set}sockopt outside sock lock
  PCI/cxgb4: Extend T3 PCI quirk to T4+ devices
  cxgb4: fix trailing zero in CIM LA dump
  cxgb4: free up resources of pf 0-3
  fib_semantics: Don't match route with mismatching tclassid
  NFC: llcp: Limit size of SDP URI
  tls: getsockopt return record sequence number
  tls: reset the crypto info if copy_from_user fails
  tls: retrun the correct IV in getsockopt
  docs: segmentation-offloads.txt: add SCTP info
  ...

1 files changed, 34 insertions, 4 deletions

diff --git a/Documentation/networking/segmentation-offloads.txt b/Documentation/networking/segmentation-offloads.txt
index 2f09455a993a..d47480b61ac6 100644
--- a/Documentation/networking/segmentation-offloads.txt
+++ b/Documentation/networking/segmentation-offloads.txt
@@ -13,6 +13,7 @@ The following technologies are described:
  * Generic Segmentation Offload - GSO
  * Generic Receive Offload - GRO
  * Partial Generic Segmentation Offload - GSO_PARTIAL
+ * SCTP accelleration with GSO - GSO_BY_FRAGS
 
 TCP Segmentation Offload
 ========================
@@ -49,6 +50,10 @@ datagram into multiple IPv4 fragments.  Many of the requirements for UDP
 fragmentation offload are the same as TSO.  However the IPv4 ID for
 fragments should not increment as a single IPv4 datagram is fragmented.
 
+UFO is deprecated: modern kernels will no longer generate UFO skbs, but can
+still receive them from tuntap and similar devices. Offload of UDP-based
+tunnel protocols is still supported.
+
 IPIP, SIT, GRE, UDP Tunnel, and Remote Checksum Offloads
 ========================================================
 
@@ -83,10 +88,10 @@ SKB_GSO_UDP_TUNNEL_CSUM.  These two additional tunnel types reflect the
 fact that the outer header also requests to have a non-zero checksum
 included in the outer header.
 
-Finally there is SKB_GSO_REMCSUM which indicates that a given tunnel header
-has requested a remote checksum offload.  In this case the inner headers
-will be left with a partial checksum and only the outer header checksum
-will be computed.
+Finally there is SKB_GSO_TUNNEL_REMCSUM which indicates that a given tunnel
+header has requested a remote checksum offload.  In this case the inner
+headers will be left with a partial checksum and only the outer header
+checksum will be computed.
 
 Generic Segmentation Offload
 ============================
@@ -128,3 +133,28 @@ values for if the header was simply duplicated.  The one exception to this
 is the outer IPv4 ID field.  It is up to the device drivers to guarantee
 that the IPv4 ID field is incremented in the case that a given header does
 not have the DF bit set.
+
+SCTP accelleration with GSO
+===========================
+
+SCTP - despite the lack of hardware support - can still take advantage of
+GSO to pass one large packet through the network stack, rather than
+multiple small packets.
+
+This requires a different approach to other offloads, as SCTP packets
+cannot be just segmented to (P)MTU. Rather, the chunks must be contained in
+IP segments, padding respected. So unlike regular GSO, SCTP can't just
+generate a big skb, set gso_size to the fragmentation point and deliver it
+to IP layer.
+
+Instead, the SCTP protocol layer builds an skb with the segments correctly
+padded and stored as chained skbs, and skb_segment() splits based on those.
+To signal this, gso_size is set to the special value GSO_BY_FRAGS.
+
+Therefore, any code in the core networking stack must be aware of the
+possibility that gso_size will be GSO_BY_FRAGS and handle that case
+appropriately. (For size checks, the skb_gso_validate_*_len family of
+helpers do this automatically.)
+
+This also affects drivers with the NETIF_F_FRAGLIST & NETIF_F_GSO_SCTP bits
+set. Note also that NETIF_F_GSO_SCTP is included in NETIF_F_GSO_SOFTWARE.