1. 29 Jul, 2014 40 commits
    • Suresh Reddy's avatar
      be2net: set EQ DB clear-intr bit in be_open() · a67b16e2
      Suresh Reddy authored
      [ Upstream commit 4cad9f3b ]
      
      On BE3, if the clear-interrupt bit of the EQ doorbell is not set the first
      time it is armed, ocassionally we have observed that the EQ doesn't raise
      anymore interrupts even if it is in armed state.
      This patch fixes this by setting the clear-interrupt bit when EQs are
      armed for the first time in be_open().
      Signed-off-by: default avatarSuresh Reddy <Suresh.Reddy@emulex.com>
      Signed-off-by: default avatarSathya Perla <sathya.perla@emulex.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      a67b16e2
    • Ben Pfaff's avatar
      netlink: Fix handling of error from netlink_dump(). · 8df19ce7
      Ben Pfaff authored
      [ Upstream commit ac30ef83 ]
      
      netlink_dump() returns a negative errno value on error.  Until now,
      netlink_recvmsg() directly recorded that negative value in sk->sk_err, but
      that's wrong since sk_err takes positive errno values.  (This manifests as
      userspace receiving a positive return value from the recv() system call,
      falsely indicating success.) This bug was introduced in the commit that
      started checking the netlink_dump() return value, commit b44d211e (netlink:
      handle errors from netlink_dump()).
      
      Multithreaded Netlink dumps are one way to trigger this behavior in
      practice, as described in the commit message for the userspace workaround
      posted here:
          http://openvswitch.org/pipermail/dev/2014-June/042339.html
      
      This commit also fixes the same bug in netlink_poll(), introduced in commit
      cd1df525 (netlink: add flow control for memory mapped I/O).
      Signed-off-by: default avatarBen Pfaff <blp@nicira.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      8df19ce7
    • Thomas Petazzoni's avatar
      net: mvneta: fix operation in 10 Mbit/s mode · 477e05a6
      Thomas Petazzoni authored
      [ Upstream commit 4d12bc63 ]
      
      As reported by Maggie Mae Roxas, the mvneta driver doesn't behave
      properly in 10 Mbit/s mode. This is due to a misconfiguration of the
      MVNETA_GMAC_AUTONEG_CONFIG register: bit MVNETA_GMAC_CONFIG_MII_SPEED
      must be set for a 100 Mbit/s speed, but cleared for a 10 Mbit/s speed,
      which the driver was not properly doing. This commit adjusts that by
      setting the MVNETA_GMAC_CONFIG_MII_SPEED bit only in 100 Mbit/s mode,
      and relying on the fact that all the speed related bits of this
      register are cleared at the beginning of the mvneta_adjust_link()
      function.
      
      This problem exists since c5aff182 ("net: mvneta: driver for
      Marvell Armada 370/XP network unit") which is the commit that
      introduced the mvneta driver in the kernel.
      
      Cc: <stable@vger.kernel.org> # v3.8+
      Fixes: c5aff182 ("net: mvneta: driver for Marvell Armada 370/XP network unit")
      Reported-by: default avatarMaggie Mae Roxas <maggie.mae.roxas@gmail.com>
      Cc: Maggie Mae Roxas <maggie.mae.roxas@gmail.com>
      Signed-off-by: default avatarThomas Petazzoni <thomas.petazzoni@free-electrons.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      477e05a6
    • Andrey Utkin's avatar
      appletalk: Fix socket referencing in skb · aabe442e
      Andrey Utkin authored
      [ Upstream commit 36beddc2 ]
      
      Setting just skb->sk without taking its reference and setting a
      destructor is invalid. However, in the places where this was done, skb
      is used in a way not requiring skb->sk setting. So dropping the setting
      of skb->sk.
      Thanks to Eric Dumazet <eric.dumazet@gmail.com> for correct solution.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79441Reported-by: default avatarEd Martin <edman007@edman007.com>
      Signed-off-by: default avatarAndrey Utkin <andrey.krieger.utkin@gmail.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      aabe442e
    • Yuchung Cheng's avatar
      tcp: fix false undo corner cases · 06fc671a
      Yuchung Cheng authored
      [ Upstream commit 6e08d5e3 ]
      
      The undo code assumes that, upon entering loss recovery, TCP
      1) always retransmit something
      2) the retransmission never fails locally (e.g., qdisc drop)
      
      so undo_marker is set in tcp_enter_recovery() and undo_retrans is
      incremented only when tcp_retransmit_skb() is successful.
      
      When the assumption is broken because TCP's cwnd is too small to
      retransmit or the retransmit fails locally. The next (DUP)ACK
      would incorrectly revert the cwnd and the congestion state in
      tcp_try_undo_dsack() or tcp_may_undo(). Subsequent (DUP)ACKs
      may enter the recovery state. The sender repeatedly enter and
      (incorrectly) exit recovery states if the retransmits continue to
      fail locally while receiving (DUP)ACKs.
      
      The fix is to initialize undo_retrans to -1 and start counting on
      the first retransmission. Always increment undo_retrans even if the
      retransmissions fail locally because they couldn't cause DSACKs to
      undo the cwnd reduction.
      Signed-off-by: default avatarYuchung Cheng <ycheng@google.com>
      Signed-off-by: default avatarNeal Cardwell <ncardwell@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      06fc671a
    • dingtianhong's avatar
      igmp: fix the problem when mc leave group · 31ae2665
      dingtianhong authored
      [ Upstream commit 52ad353a ]
      
      The problem was triggered by these steps:
      
      1) create socket, bind and then setsockopt for add mc group.
         mreq.imr_multiaddr.s_addr = inet_addr("255.0.0.37");
         mreq.imr_interface.s_addr = inet_addr("192.168.1.2");
         setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
      
      2) drop the mc group for this socket.
         mreq.imr_multiaddr.s_addr = inet_addr("255.0.0.37");
         mreq.imr_interface.s_addr = inet_addr("0.0.0.0");
         setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
      
      3) and then drop the socket, I found the mc group was still used by the dev:
      
         netstat -g
      
         Interface       RefCnt Group
         --------------- ------ ---------------------
         eth2		   1	  255.0.0.37
      
      Normally even though the IP_DROP_MEMBERSHIP return error, the mc group still need
      to be released for the netdev when drop the socket, but this process was broken when
      route default is NULL, the reason is that:
      
      The ip_mc_leave_group() will choose the in_dev by the imr_interface.s_addr, if input addr
      is NULL, the default route dev will be chosen, then the ifindex is got from the dev,
      then polling the inet->mc_list and return -ENODEV, but if the default route dev is NULL,
      the in_dev and ifIndex is both NULL, when polling the inet->mc_list, the mc group will be
      released from the mc_list, but the dev didn't dec the refcnt for this mc group, so
      when dropping the socket, the mc_list is NULL and the dev still keep this group.
      
      v1->v2: According Hideaki's suggestion, we should align with IPv6 (RFC3493) and BSDs,
      	so I add the checking for the in_dev before polling the mc_list, make sure when
      	we remove the mc group, dec the refcnt to the real dev which was using the mc address.
      	The problem would never happened again.
      Signed-off-by: default avatarDing Tianhong <dingtianhong@huawei.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      31ae2665
    • Loic Prylli's avatar
      net: Fix NETDEV_CHANGE notifier usage causing spurious arp flush · 4c824ea2
      Loic Prylli authored
      [ Upstream commit 54951194 ]
      
      A bug was introduced in NETDEV_CHANGE notifier sequence causing the
      arp table to be sometimes spuriously cleared (including manual arp
      entries marked permanent), upon network link carrier changes.
      
      The changed argument for the notifier was applied only to a single
      caller of NETDEV_CHANGE, missing among others netdev_state_change().
      So upon net_carrier events induced by the network, which are
      triggering a call to netdev_state_change(), arp_netdev_event() would
      decide whether to clear or not arp cache based on random/junk stack
      values (a kind of read buffer overflow).
      
      Fixes: be9efd36 ("net: pass changed flags along with NETDEV_CHANGE event")
      Fixes: 6c8b4e3f ("arp: flush arp cache on IFF_NOARP change")
      Signed-off-by: default avatarLoic Prylli <loicp@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      4c824ea2
    • Bjørn Mork's avatar
      net: qmi_wwan: add two Sierra Wireless/Netgear devices · 196162de
      Bjørn Mork authored
      [ Upstream commit 53433300 ]
      
      Add two device IDs found in an out-of-tree driver downloadable
      from Netgear.
      Signed-off-by: default avatarBjørn Mork <bjorn@mork.no>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      196162de
    • Bernd Wachter's avatar
      net: qmi_wwan: Add ID for Telewell TW-LTE 4G v2 · 0b92a040
      Bernd Wachter authored
      [ Upstream commit 8dcb4b15 ]
      
      There's a new version of the Telewell 4G modem working with, but not
      recognized by this driver.
      Signed-off-by: default avatarBernd Wachter <bernd.wachter@jolla.com>
      Acked-by: default avatarBjørn Mork <bjorn@mork.no>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      0b92a040
    • Edward Allcutt's avatar
      ipv4: icmp: Fix pMTU handling for rare case · 1f947b07
      Edward Allcutt authored
      [ Upstream commit 68b7107b ]
      
      Some older router implementations still send Fragmentation Needed
      errors with the Next-Hop MTU field set to zero. This is explicitly
      described as an eventuality that hosts must deal with by the
      standard (RFC 1191) since older standards specified that those
      bits must be zero.
      
      Linux had a generic (for all of IPv4) implementation of the algorithm
      described in the RFC for searching a list of MTU plateaus for a good
      value. Commit 46517008 ("ipv4: Kill ip_rt_frag_needed().")
      removed this as part of the changes to remove the routing cache.
      Subsequently any Fragmentation Needed packet with a zero Next-Hop
      MTU has been discarded without being passed to the per-protocol
      handlers or notifying userspace for raw sockets.
      
      When there is a router which does not implement RFC 1191 on an
      MTU limited path then this results in stalled connections since
      large packets are discarded and the local protocols are not
      notified so they never attempt to lower the pMTU.
      
      One example I have seen is an OpenBSD router terminating IPSec
      tunnels. It's worth pointing out that this case is distinct from
      the BSD 4.2 bug which incorrectly calculated the Next-Hop MTU
      since the commit in question dismissed that as a valid concern.
      
      All of the per-protocols handlers implement the simple approach from
      RFC 1191 of immediately falling back to the minimum value. Although
      this is sub-optimal it is vastly preferable to connections hanging
      indefinitely.
      
      Remove the Next-Hop MTU != 0 check and allow such packets
      to follow the normal path.
      
      Fixes: 46517008 ("ipv4: Kill ip_rt_frag_needed().")
      Signed-off-by: default avatarEdward Allcutt <edward.allcutt@openmarket.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1f947b07
    • Christoph Paasch's avatar
      tcp: Fix divide by zero when pushing during tcp-repair · 9f22c5c1
      Christoph Paasch authored
      [ Upstream commit 5924f17a ]
      
      When in repair-mode and TCP_RECV_QUEUE is set, we end up calling
      tcp_push with mss_now being 0. If data is in the send-queue and
      tcp_set_skb_tso_segs gets called, we crash because it will divide by
      mss_now:
      
      [  347.151939] divide error: 0000 [#1] SMP
      [  347.152907] Modules linked in:
      [  347.152907] CPU: 1 PID: 1123 Comm: packetdrill Not tainted 3.16.0-rc2 #4
      [  347.152907] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
      [  347.152907] task: f5b88540 ti: f3c82000 task.ti: f3c82000
      [  347.152907] EIP: 0060:[<c1601359>] EFLAGS: 00210246 CPU: 1
      [  347.152907] EIP is at tcp_set_skb_tso_segs+0x49/0xa0
      [  347.152907] EAX: 00000b67 EBX: f5acd080 ECX: 00000000 EDX: 00000000
      [  347.152907] ESI: f5a28f40 EDI: f3c88f00 EBP: f3c83d10 ESP: f3c83d00
      [  347.152907]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
      [  347.152907] CR0: 80050033 CR2: 083158b0 CR3: 35146000 CR4: 000006b0
      [  347.152907] Stack:
      [  347.152907]  c167f9d9 f5acd080 000005b4 00000002 f3c83d20 c16013e6 f3c88f00 f5acd080
      [  347.152907]  f3c83da0 c1603b5a f3c83d38 c10a0188 00000000 00000000 f3c83d84 c10acc85
      [  347.152907]  c1ad5ec0 00000000 00000000 c1ad679c 010003e0 00000000 00000000 f3c88fc8
      [  347.152907] Call Trace:
      [  347.152907]  [<c167f9d9>] ? apic_timer_interrupt+0x2d/0x34
      [  347.152907]  [<c16013e6>] tcp_init_tso_segs+0x36/0x50
      [  347.152907]  [<c1603b5a>] tcp_write_xmit+0x7a/0xbf0
      [  347.152907]  [<c10a0188>] ? up+0x28/0x40
      [  347.152907]  [<c10acc85>] ? console_unlock+0x295/0x480
      [  347.152907]  [<c10ad24f>] ? vprintk_emit+0x1ef/0x4b0
      [  347.152907]  [<c1605716>] __tcp_push_pending_frames+0x36/0xd0
      [  347.152907]  [<c15f4860>] tcp_push+0xf0/0x120
      [  347.152907]  [<c15f7641>] tcp_sendmsg+0xf1/0xbf0
      [  347.152907]  [<c116d920>] ? kmem_cache_free+0xf0/0x120
      [  347.152907]  [<c106a682>] ? __sigqueue_free+0x32/0x40
      [  347.152907]  [<c106a682>] ? __sigqueue_free+0x32/0x40
      [  347.152907]  [<c114f0f0>] ? do_wp_page+0x3e0/0x850
      [  347.152907]  [<c161c36a>] inet_sendmsg+0x4a/0xb0
      [  347.152907]  [<c1150269>] ? handle_mm_fault+0x709/0xfb0
      [  347.152907]  [<c15a006b>] sock_aio_write+0xbb/0xd0
      [  347.152907]  [<c1180b79>] do_sync_write+0x69/0xa0
      [  347.152907]  [<c1181023>] vfs_write+0x123/0x160
      [  347.152907]  [<c1181d55>] SyS_write+0x55/0xb0
      [  347.152907]  [<c167f0d8>] sysenter_do_call+0x12/0x28
      
      This can easily be reproduced with the following packetdrill-script (the
      "magic" with netem, sk_pacing and limit_output_bytes is done to prevent
      the kernel from pushing all segments, because hitting the limit without
      doing this is not so easy with packetdrill):
      
      0   socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
      +0  setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
      
      +0  bind(3, ..., ...) = 0
      +0  listen(3, 1) = 0
      
      +0  < S 0:0(0) win 32792 <mss 1460>
      +0  > S. 0:0(0) ack 1 <mss 1460>
      +0.1  < . 1:1(0) ack 1 win 65000
      
      +0  accept(3, ..., ...) = 4
      
      // This forces that not all segments of the snd-queue will be pushed
      +0 `tc qdisc add dev tun0 root netem delay 10ms`
      +0 `sysctl -w net.ipv4.tcp_limit_output_bytes=2`
      +0 setsockopt(4, SOL_SOCKET, 47, [2], 4) = 0
      
      +0 write(4,...,10000) = 10000
      +0 write(4,...,10000) = 10000
      
      // Set tcp-repair stuff, particularly TCP_RECV_QUEUE
      +0 setsockopt(4, SOL_TCP, 19, [1], 4) = 0
      +0 setsockopt(4, SOL_TCP, 20, [1], 4) = 0
      
      // This now will make the write push the remaining segments
      +0 setsockopt(4, SOL_SOCKET, 47, [20000], 4) = 0
      +0 `sysctl -w net.ipv4.tcp_limit_output_bytes=130000`
      
      // Now we will crash
      +0 write(4,...,1000) = 1000
      
      This happens since ec342325 (tcp: fix retransmission in repair
      mode). Prior to that, the call to tcp_push was prevented by a check for
      tp->repair.
      
      The patch fixes it, by adding the new goto-label out_nopush. When exiting
      tcp_sendmsg and a push is not required, which is the case for tp->repair,
      we go to this label.
      
      When repairing and calling send() with TCP_RECV_QUEUE, the data is
      actually put in the receive-queue. So, no push is required because no
      data has been added to the send-queue.
      
      Cc: Andrew Vagin <avagin@openvz.org>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Fixes: ec342325 (tcp: fix retransmission in repair mode)
      Signed-off-by: default avatarChristoph Paasch <christoph.paasch@uclouvain.be>
      Acked-by: default avatarAndrew Vagin <avagin@openvz.org>
      Acked-by: default avatarPavel Emelyanov <xemul@parallels.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      9f22c5c1
    • Eric Dumazet's avatar
      bnx2x: fix possible panic under memory stress · 7ec8d47a
      Eric Dumazet authored
      [ Upstream commit 07b0f009 ]
      
      While it is legal to kfree(NULL), it is not wise to use :
      put_page(virt_to_head_page(NULL))
      
       BUG: unable to handle kernel paging request at ffffeba400000000
       IP: [<ffffffffc01f5928>] virt_to_head_page+0x36/0x44 [bnx2x]
      Reported-by: default avatarMichel Lespinasse <walken@google.com>
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Ariel Elior <ariel.elior@qlogic.com>
      Fixes: d46d132c ("bnx2x: use netdev_alloc_frag()")
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      7ec8d47a
    • Eric Dumazet's avatar
      ipv4: irq safe sk_dst_[re]set() and ipv4_sk_update_pmtu() fix · 8728b0c1
      Eric Dumazet authored
      [ Upstream commit 7f502361 ]
      
      We have two different ways to handle changes to sk->sk_dst
      
      First way (used by TCP) assumes socket lock is owned by caller, and use
      no extra lock : __sk_dst_set() & __sk_dst_reset()
      
      Another way (used by UDP) uses sk_dst_lock because socket lock is not
      always taken. Note that sk_dst_lock is not softirq safe.
      
      These ways are not inter changeable for a given socket type.
      
      ipv4_sk_update_pmtu(), added in linux-3.8, added a race, as it used
      the socket lock as synchronization, but users might be UDP sockets.
      
      Instead of converting sk_dst_lock to a softirq safe version, use xchg()
      as we did for sk_rx_dst in commit e47eb5df ("udp: ipv4: do not use
      sk_dst_lock from softirq context")
      
      In a follow up patch, we probably can remove sk_dst_lock, as it is
      only used in IPv6.
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Steffen Klassert <steffen.klassert@secunet.com>
      Fixes: 9cb3a50c ("ipv4: Invalidate the socket cached route on pmtu events if possible")
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      8728b0c1
    • Eric Dumazet's avatar
      ipv4: fix dst race in sk_dst_get() · 591b1e1b
      Eric Dumazet authored
      [ Upstream commit f8864972 ]
      
      When IP route cache had been removed in linux-3.6, we broke assumption
      that dst entries were all freed after rcu grace period. DST_NOCACHE
      dst were supposed to be freed from dst_release(). But it appears
      we want to keep such dst around, either in UDP sockets or tunnels.
      
      In sk_dst_get() we need to make sure dst refcount is not 0
      before incrementing it, or else we might end up freeing a dst
      twice.
      
      DST_NOCACHE set on a dst does not mean this dst can not be attached
      to a socket or a tunnel.
      
      Then, before actual freeing, we need to observe a rcu grace period
      to make sure all other cpus can catch the fact the dst is no longer
      usable.
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Reported-by: default avatarDormando <dormando@rydia.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      591b1e1b
    • Wei-Chun Chao's avatar
      net: fix UDP tunnel GSO of frag_list GRO packets · 1ea46433
      Wei-Chun Chao authored
      [ Upstream commit 5882a07c ]
      
      This patch fixes a kernel BUG_ON in skb_segment. It is hit when
      testing two VMs on openvswitch with one VM acting as VXLAN gateway.
      
      During VXLAN packet GSO, skb_segment is called with skb->data
      pointing to inner TCP payload. skb_segment calls skb_network_protocol
      to retrieve the inner protocol. skb_network_protocol actually expects
      skb->data to point to MAC and it calls pskb_may_pull with ETH_HLEN.
      This ends up pulling in ETH_HLEN data from header tail. As a result,
      pskb_trim logic is skipped and BUG_ON is hit later.
      
      Move skb_push in front of skb_network_protocol so that skb->data
      lines up properly.
      
      kernel BUG at net/core/skbuff.c:2999!
      Call Trace:
      [<ffffffff816ac412>] tcp_gso_segment+0x122/0x410
      [<ffffffff816bc74c>] inet_gso_segment+0x13c/0x390
      [<ffffffff8164b39b>] skb_mac_gso_segment+0x9b/0x170
      [<ffffffff816b3658>] skb_udp_tunnel_segment+0xd8/0x390
      [<ffffffff816b3c00>] udp4_ufo_fragment+0x120/0x140
      [<ffffffff816bc74c>] inet_gso_segment+0x13c/0x390
      [<ffffffff8109d742>] ? default_wake_function+0x12/0x20
      [<ffffffff8164b39b>] skb_mac_gso_segment+0x9b/0x170
      [<ffffffff8164b4d0>] __skb_gso_segment+0x60/0xc0
      [<ffffffff8164b6b3>] dev_hard_start_xmit+0x183/0x550
      [<ffffffff8166c91e>] sch_direct_xmit+0xfe/0x1d0
      [<ffffffff8164bc94>] __dev_queue_xmit+0x214/0x4f0
      [<ffffffff8164bf90>] dev_queue_xmit+0x10/0x20
      [<ffffffff81687edb>] ip_finish_output+0x66b/0x890
      [<ffffffff81688a58>] ip_output+0x58/0x90
      [<ffffffff816c628f>] ? fib_table_lookup+0x29f/0x350
      [<ffffffff816881c9>] ip_local_out_sk+0x39/0x50
      [<ffffffff816cbfad>] iptunnel_xmit+0x10d/0x130
      [<ffffffffa0212200>] vxlan_xmit_skb+0x1d0/0x330 [vxlan]
      [<ffffffffa02a3919>] vxlan_tnl_send+0x129/0x1a0 [openvswitch]
      [<ffffffffa02a2cd6>] ovs_vport_send+0x26/0xa0 [openvswitch]
      [<ffffffffa029931e>] do_output+0x2e/0x50 [openvswitch]
      Signed-off-by: default avatarWei-Chun Chao <weichunc@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1ea46433
    • Li RongQing's avatar
      8021q: fix a potential memory leak · 50cd0c76
      Li RongQing authored
      [ Upstream commit 916c1689 ]
      
      skb_cow called in vlan_reorder_header does not free the skb when it failed,
      and vlan_reorder_header returns NULL to reset original skb when it is called
      in vlan_untag, lead to a memory leak.
      Signed-off-by: default avatarLi RongQing <roy.qing.li@gmail.com>
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      50cd0c76
    • Daniel Borkmann's avatar
      net: sctp: check proc_dointvec result in proc_sctp_do_auth · a6c33e4d
      Daniel Borkmann authored
      [ Upstream commit 24599e61 ]
      
      When writing to the sysctl field net.sctp.auth_enable, it can well
      be that the user buffer we handed over to proc_dointvec() via
      proc_sctp_do_auth() handler contains something other than integers.
      
      In that case, we would set an uninitialized 4-byte value from the
      stack to net->sctp.auth_enable that can be leaked back when reading
      the sysctl variable, and it can unintentionally turn auth_enable
      on/off based on the stack content since auth_enable is interpreted
      as a boolean.
      
      Fix it up by making sure proc_dointvec() returned sucessfully.
      
      Fixes: b14878cc ("net: sctp: cache auth_enable per endpoint")
      Reported-by: default avatarFlorian Westphal <fwestpha@redhat.com>
      Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
      Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      Acked-by: default avatarVlad Yasevich <vyasevich@gmail.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      a6c33e4d
    • Neal Cardwell's avatar
      tcp: fix tcp_match_skb_to_sack() for unaligned SACK at end of an skb · 5f8c661b
      Neal Cardwell authored
      [ Upstream commit 2cd0d743 ]
      
      If there is an MSS change (or misbehaving receiver) that causes a SACK
      to arrive that covers the end of an skb but is less than one MSS, then
      tcp_match_skb_to_sack() was rounding up pkt_len to the full length of
      the skb ("Round if necessary..."), then chopping all bytes off the skb
      and creating a zero-byte skb in the write queue.
      
      This was visible now because the recently simplified TLP logic in
      bef1909e ("tcp: fixing TLP's FIN recovery") could find that 0-byte
      skb at the end of the write queue, and now that we do not check that
      skb's length we could send it as a TLP probe.
      
      Consider the following example scenario:
      
       mss: 1000
       skb: seq: 0 end_seq: 4000  len: 4000
       SACK: start_seq: 3999 end_seq: 4000
      
      The tcp_match_skb_to_sack() code will compute:
      
       in_sack = false
       pkt_len = start_seq - TCP_SKB_CB(skb)->seq = 3999 - 0 = 3999
       new_len = (pkt_len / mss) * mss = (3999/1000)*1000 = 3000
       new_len += mss = 4000
      
      Previously we would find the new_len > skb->len check failing, so we
      would fall through and set pkt_len = new_len = 4000 and chop off
      pkt_len of 4000 from the 4000-byte skb, leaving a 0-byte segment
      afterward in the write queue.
      
      With this new commit, we notice that the new new_len >= skb->len check
      succeeds, so that we return without trying to fragment.
      
      Fixes: adb92db8 ("tcp: Make SACK code to split only at mss boundaries")
      Reported-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarNeal Cardwell <ncardwell@google.com>
      Cc: Eric Dumazet <edumazet@google.com>
      Cc: Yuchung Cheng <ycheng@google.com>
      Cc: Ilpo Jarvinen <ilpo.jarvinen@helsinki.fi>
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      5f8c661b
    • Daniel Borkmann's avatar
      net: sctp: propagate sysctl errors from proc_do* properly · ad51ee3f
      Daniel Borkmann authored
      [ Upstream commit ff5e92c1 ]
      
      sysctl handler proc_sctp_do_hmac_alg(), proc_sctp_do_rto_min() and
      proc_sctp_do_rto_max() do not properly reflect some error cases
      when writing values via sysctl from internal proc functions such
      as proc_dointvec() and proc_dostring().
      
      In all these cases we pass the test for write != 0 and partially
      do additional work just to notice that additional sanity checks
      fail and we return with hard-coded -EINVAL while proc_do*
      functions might also return different errors. So fix this up by
      simply testing a successful return of proc_do* right after
      calling it.
      
      This also allows to propagate its return value onwards to the user.
      While touching this, also fix up some minor style issues.
      
      Fixes: 4f3fdf3b ("sctp: add check rto_min and rto_max in sysctl")
      Fixes: 3c68198e ("sctp: Make hmac algorithm selection for cookie generation dynamic")
      Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      ad51ee3f
    • Tyler Hall's avatar
      slcan: Port write_wakeup deadlock fix from slip · a0df2450
      Tyler Hall authored
      [ Upstream commit a8e83b17 ]
      
      The commit "slip: Fix deadlock in write_wakeup" fixes a deadlock caused
      by a change made in both slcan and slip. This is a direct port of that
      fix.
      Signed-off-by: default avatarTyler Hall <tylerwhall@gmail.com>
      Cc: Oliver Hartkopp <socketcan@hartkopp.net>
      Cc: Andre Naujoks <nautsch2@gmail.com>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      a0df2450
    • Dmitry Popov's avatar
      ip_tunnel: fix ip_tunnel_lookup · a1258d53
      Dmitry Popov authored
      [ Upstream commit e0056593 ]
      
      This patch fixes 3 similar bugs where incoming packets might be routed into
      wrong non-wildcard tunnels:
      
      1) Consider the following setup:
          ip address add 1.1.1.1/24 dev eth0
          ip address add 1.1.1.2/24 dev eth0
          ip tunnel add ipip1 remote 2.2.2.2 local 1.1.1.1 mode ipip dev eth0
          ip link set ipip1 up
      
      Incoming ipip packets from 2.2.2.2 were routed into ipip1 even if it has dst =
      1.1.1.2. Moreover even if there was wildcard tunnel like
         ip tunnel add ipip0 remote 2.2.2.2 local any mode ipip dev eth0
      but it was created before explicit one (with local 1.1.1.1), incoming ipip
      packets with src = 2.2.2.2 and dst = 1.1.1.2 were still routed into ipip1.
      
      Same issue existed with all tunnels that use ip_tunnel_lookup (gre, vti)
      
      2)  ip address add 1.1.1.1/24 dev eth0
          ip tunnel add ipip1 remote 2.2.146.85 local 1.1.1.1 mode ipip dev eth0
          ip link set ipip1 up
      
      Incoming ipip packets with dst = 1.1.1.1 were routed into ipip1, no matter what
      src address is. Any remote ip address which has ip_tunnel_hash = 0 raised this
      issue, 2.2.146.85 is just an example, there are more than 4 million of them.
      And again, wildcard tunnel like
         ip tunnel add ipip0 remote any local 1.1.1.1 mode ipip dev eth0
      wouldn't be ever matched if it was created before explicit tunnel like above.
      
      Gre & vti tunnels had the same issue.
      
      3)  ip address add 1.1.1.1/24 dev eth0
          ip tunnel add gre1 remote 2.2.146.84 local 1.1.1.1 key 1 mode gre dev eth0
          ip link set gre1 up
      
      Any incoming gre packet with key = 1 were routed into gre1, no matter what
      src/dst addresses are. Any remote ip address which has ip_tunnel_hash = 0 raised
      the issue, 2.2.146.84 is just an example, there are more than 4 million of them.
      Wildcard tunnel like
         ip tunnel add gre2 remote any local any key 1 mode gre dev eth0
      wouldn't be ever matched if it was created before explicit tunnel like above.
      
      All this stuff happened because while looking for a wildcard tunnel we didn't
      check that matched tunnel is a wildcard one. Fixed.
      Signed-off-by: default avatarDmitry Popov <ixaphire@qrator.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      a1258d53
    • David Ertman's avatar
      e1000e: Fix SHRA register access for 82579 · b0d71151
      David Ertman authored
      commit 96dee024 upstream.
      
      Previous commit c3a0dce3 fixed an overrun for the RAR on i218 devices.
      This commit also attempted to homogenize the RAR/SHRA access for all parts
      accessed by the e1000e driver.  This change introduced an error for
      assigning MAC addresses to guest OS's for 82579 devices.
      
      Only RAR[0] is accessible to the driver for 82579 parts, and additional
      addresses must be placed into the SHRA[L|H] registers.  The rar_entry_count
      was changed in the previous commit to an inaccurate value that accounted
      for all RAR and SHRA registers, not just the ones usable by the driver.
      
      This patch fixes the count to the correct value and adjusts the
      e1000_rar_set_pch2lan() function to user the correct index.
      
      Cc: John Greene <jogreene@redhat.com>
      Signed-off-by: default avatarDave Ertman <davidx.m.ertman@intel.com>
      Tested-by: default avatarAaron Brown <aaron.f.brown@intel.com>
      Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
      Cc: "Alexander Y. Fomichev" <aleksandr.fomichev@x5.ru>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      b0d71151
    • Emmanuel Grumbach's avatar
      iwlwifi: dvm: don't enable CTS to self · 3a0722dd
      Emmanuel Grumbach authored
      commit 43d826ca upstream.
      
      We should always prefer to use full RTS protection. Using
      CTS to self gives a meaningless improvement, but this flow
      is much harder for the firmware which is likely to have
      issues with it.
      Signed-off-by: default avatarEmmanuel Grumbach <emmanuel.grumbach@intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      3a0722dd
    • Niu Yawei's avatar
      quota: missing lock in dqcache_shrink_scan() · 51a00934
      Niu Yawei authored
      commit d68aab6b upstream.
      
      Commit 1ab6c499 (fs: convert fs shrinkers to new scan/count API)
      accidentally removed locking from quota shrinker. Fix it -
      dqcache_shrink_scan() should use dq_list_lock to protect the
      scan on free_dquots list.
      
      Fixes: 1ab6c499Signed-off-by: default avatarNiu Yawei <yawei.niu@intel.com>
      Signed-off-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      51a00934
    • Stefan Assmann's avatar
      igb: do a reset on SR-IOV re-init if device is down · 4e873a3d
      Stefan Assmann authored
      commit 76252723 upstream.
      
      To properly re-initialize SR-IOV it is necessary to reset the device
      even if it is already down. Not doing this may result in Tx unit hangs.
      Signed-off-by: default avatarStefan Assmann <sassmann@kpanic.de>
      Tested-by: default avatarAaron Brown <aaron.f.brown@intel.com>
      Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      4e873a3d
    • Todd Fujinaka's avatar
      igb: Workaround for i210 Errata 25: Slow System Clock · 13089c3a
      Todd Fujinaka authored
      commit 94826487 upstream.
      
      On some devices, the internal PLL circuit occasionally provides the
      wrong clock frequency after power up. The probability of failure is less
      than one failure per 1000 power cycles. When the failure occurs, the
      internal clock frequency is around 1/20 of the correct frequency.
      Signed-off-by: default avatarTodd Fujinaka <todd.fujinaka@intel.com>
      Tested-by: default avatarAaron Brown <aaron.f.brown@intel.com>
      Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      13089c3a
    • Guenter Roeck's avatar
      hwmon: (adt7470) Fix writes to temperature limit registers · c37dcd9c
      Guenter Roeck authored
      commit de12d6f4 upstream.
      
      Temperature limit registers are signed. Limits therefore need
      to be clamped to (-128, 127) degrees C and not to (0, 255)
      degrees C.
      
      Without this fix, writing a limit of 128 degrees C sets the
      actual limit to -128 degrees C.
      Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Reviewed-by: default avatarAxel Lin <axel.lin@ingics.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      c37dcd9c
    • Axel Lin's avatar
      hwmon: (da9052) Don't use dash in the name attribute · 9de942f9
      Axel Lin authored
      commit ee14b644 upstream.
      
      Dashes are not allowed in hwmon name attributes.
      Use "da9052" instead of "da9052-hwmon".
      Signed-off-by: default avatarAxel Lin <axel.lin@ingics.com>
      Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      9de942f9
    • Axel Lin's avatar
      hwmon: (da9055) Don't use dash in the name attribute · 6687e933
      Axel Lin authored
      commit 6b00f440 upstream.
      
      Dashes are not allowed in hwmon name attributes.
      Use "da9055" instead of "da9055-hwmon".
      Signed-off-by: default avatarAxel Lin <axel.lin@ingics.com>
      Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      6687e933
    • zhangwei(Jovi)'s avatar
      tracing: Add TRACE_ITER_PRINTK flag check in __trace_puts/__trace_bputs · e12331d9
      zhangwei(Jovi) authored
      commit f0160a5a upstream.
      
      The TRACE_ITER_PRINTK check in __trace_puts/__trace_bputs is missing,
      so add it, to be consistent with __trace_printk/__trace_bprintk.
      Those functions are all called by the same function: trace_printk().
      
      Link: http://lkml.kernel.org/p/51E7A7D6.8090900@huawei.comSigned-off-by: default avatarzhangwei(Jovi) <jovi.zhangwei@huawei.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      e12331d9
    • zhangwei(Jovi)'s avatar
      tracing: Add ftrace_trace_stack into __trace_puts/__trace_bputs · cce7b584
      zhangwei(Jovi) authored
      commit 8abfb872 upstream.
      
      Currently trace option stacktrace is not applicable for
      trace_printk with constant string argument, the reason is
      in __trace_puts/__trace_bputs ftrace_trace_stack is missing.
      
      In contrast, when using trace_printk with non constant string
      argument(will call into __trace_printk/__trace_bprintk), then
      trace option stacktrace is workable, this inconstant result
      will confuses users a lot.
      
      Link: http://lkml.kernel.org/p/51E7A7C9.9040401@huawei.comSigned-off-by: default avatarzhangwei(Jovi) <jovi.zhangwei@huawei.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      cce7b584
    • Steven Rostedt (Red Hat)'s avatar
      tracing: Fix graph tracer with stack tracer on other archs · 48b19dc8
      Steven Rostedt (Red Hat) authored
      commit 5f8bf2d2 upstream.
      
      Running my ftrace tests on PowerPC, it failed the test that checks
      if function_graph tracer is affected by the stack tracer. It was.
      Looking into this, I found that the update_function_graph_func()
      must be called even if the trampoline function is not changed.
      This is because archs like PowerPC do not support ftrace_ops being
      passed by assembly and instead uses a helper function (what the
      trampoline function points to). Since this function is not changed
      even when multiple ftrace_ops are added to the code, the test that
      falls out before calling update_function_graph_func() will miss that
      the update must still be done.
      
      Call update_function_graph_function() for all calls to
      update_ftrace_function()
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      48b19dc8
    • Anand Avati's avatar
      fuse: ignore entry-timeout on LOOKUP_REVAL · 21861467
      Anand Avati authored
      commit 154210cc upstream.
      
      The following test case demonstrates the bug:
      
        sh# mount -t glusterfs localhost:meta-test /mnt/one
      
        sh# mount -t glusterfs localhost:meta-test /mnt/two
      
        sh# echo stuff > /mnt/one/file; rm -f /mnt/two/file; echo stuff > /mnt/one/file
        bash: /mnt/one/file: Stale file handle
      
        sh# echo stuff > /mnt/one/file; rm -f /mnt/two/file; sleep 1; echo stuff > /mnt/one/file
      
      On the second open() on /mnt/one, FUSE would have used the old
      nodeid (file handle) trying to re-open it. Gluster is returning
      -ESTALE. The ESTALE propagates back to namei.c:filename_lookup()
      where lookup is re-attempted with LOOKUP_REVAL. The right
      behavior now, would be for FUSE to ignore the entry-timeout and
      and do the up-call revalidation. Instead FUSE is ignoring
      LOOKUP_REVAL, succeeding the revalidation (because entry-timeout
      has not passed), and open() is again retried on the old file
      handle and finally the ESTALE is going back to the application.
      
      Fix: if revalidation is happening with LOOKUP_REVAL, then ignore
      entry-timeout and always do the up-call.
      Signed-off-by: default avatarAnand Avati <avati@redhat.com>
      Reviewed-by: default avatarNiels de Vos <ndevos@redhat.com>
      Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      21861467
    • Miklos Szeredi's avatar
      fuse: handle large user and group ID · 366a83d6
      Miklos Szeredi authored
      commit 233a01fa upstream.
      
      If the number in "user_id=N" or "group_id=N" mount options was larger than
      INT_MAX then fuse returned EINVAL.
      
      Fix this to handle all valid uid/gid values.
      Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      366a83d6
    • Miklos Szeredi's avatar
      fuse: timeout comparison fix · de6ab0e7
      Miklos Szeredi authored
      commit 126b9d43 upstream.
      
      As suggested by checkpatch.pl, use time_before64() instead of direct
      comparison of jiffies64 values.
      Signed-off-by: default avatarMiklos Szeredi <mszeredi@suse.cz>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      de6ab0e7
    • Loic Poulain's avatar
      Bluetooth: Ignore H5 non-link packets in non-active state · 5233db85
      Loic Poulain authored
      commit 48439d50 upstream.
      
      When detecting a non-link packet, h5_reset_rx() frees the Rx skb.
      Not returning after that will cause the upcoming h5_rx_payload()
      call to dereference a now NULL Rx skb and trigger a kernel oops.
      Signed-off-by: default avatarLoic Poulain <loic.poulain@intel.com>
      Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      5233db85
    • K. Y. Srinivasan's avatar
      Drivers: hv: util: Fix a bug in the KVP code · 65769bee
      K. Y. Srinivasan authored
      commit 9bd2d0df upstream.
      
      Add code to poll the channel since we process only one message
      at a time and the host may not interrupt us. Also increase the
      receive buffer size since some KVP messages are close to 8K bytes in size.
      Signed-off-by: default avatarK. Y. Srinivasan <kys@microsoft.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      65769bee
    • Takashi Iwai's avatar
      ALSA: hda - Fix broken PM due to incomplete i915 initialization · 02c9a938
      Takashi Iwai authored
      commit 4da63c6f upstream.
      
      When the initialization of Intel HDMI controller fails due to missing
      i915 kernel symbols (e.g. HD-audio is built in while i915 is module),
      the driver discontinues the probe.  However, since the probe was done
      asynchronously, the driver object still remains, thus the relevant PM
      ops are still called at suspend/resume. This results in the bad access
      to the incomplete audio card object, eventually leads to Oops or stall
      at PM.
      
      This patch adds the missing checks of chip->init_failed flag at each
      PM callback in order to fix the problem above.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79561Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      02c9a938
    • Hans de Goede's avatar
      media: gspca_pac7302: Add new usb-id for Genius i-Look 317 · 3f88bf83
      Hans de Goede authored
      commit 242841d3 upstream.
      Tested-and-reported-by: default avataryullaw <yullaw@mageia.cz>
      Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarMauro Carvalho Chehab <m.chehab@samsung.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      3f88bf83
    • Abbas Raza's avatar
      usb: chipidea: udc: Disable auto ZLP generation on ep0 · 1a24f220
      Abbas Raza authored
      commit 953c6646 upstream.
      
      There are 2 methods for ZLP (zero-length packet) generation:
      1) In software
      2) Automatic generation by device controller
      
      1) is implemented in UDC driver and it attaches ZLP to IN packet if
         descriptor->size < wLength
      2) can be enabled/disabled by setting ZLT bit in the QH
      
      When gadget ffs is connected to ubuntu host, the host sends
      get descriptor request and wLength in setup packet is 255 while the
      size of descriptor which will be sent by gadget in IN packet is
      64 byte. So the composite driver sets req->zero = 1.
      In UDC driver following code will be executed then
      
              if (hwreq->req.zero && hwreq->req.length
                  && (hwreq->req.length % hwep->ep.maxpacket == 0))
                      add_td_to_list(hwep, hwreq, 0);
      
      Case-A:
      So in case of ubuntu host, UDC driver will attach a ZLP to the IN packet.
      ubuntu host will request 255 byte in IN request, gadget will send 64 byte
      with ZLP and host will come to know that there is no more data.
      But hold on, by default ZLT=0 for endpoint 0 so hardware also tries to
      automatically generate the ZLP which blocks enumeration for ~6 seconds due
      to endpoint 0 STALL, NAKs are sent to host for any requests (OUT/PING)
      
      Case-B:
      In case when gadget ffs is connected to Apple device, Apple device sends
      setup packet with wLength=64. So descriptor->size = 64 and wLength=64
      therefore req->zero = 0 and UDC driver will not attach any ZLP to the
      IN packet. Apple device requests 64 bytes, gets 64 bytes and doesn't
      further request for IN data. But ZLT=0 by default for endpoint 0 so
      hardware tries to automatically generate the ZLP which blocks enumeration
      for ~6 seconds due to endpoint 0 STALL, NAKs are sent to host for any
      requests (OUT/PING)
      
      According to USB2.0 specs:
      
          8.5.3.2 Variable-length Data Stage
          A control pipe may have a variable-length data phase in which the
          host requests more data than is contained in the specified data
          structure. When all of the data structure is returned to the host,
          the function should indicate that the Data stage is ended by
          returning a packet that is shorter than the MaxPacketSize for the
          pipe. If the data structure is an exact multiple of wMaxPacketSize
          for the pipe, the function will return a zero-length packet to indicate
          the end of the Data stage.
      
      In Case-A mentioned above:
      If we disable software ZLP generation & ZLT=0 for endpoint 0 OR if software
      ZLP generation is not disabled but we set ZLT=1 for endpoint 0 then
      enumeration doesn't block for 6 seconds.
      
      In Case-B mentioned above:
      If we disable software ZLP generation & ZLT=0 for endpoint then enumeration
      still blocks due to ZLP automatically generated by hardware and host not needing
      it. But if we keep software ZLP generation enabled but we set ZLT=1 for
      endpoint 0 then enumeration doesn't block for 6 seconds.
      
      So the proper solution for this issue seems to disable automatic ZLP generation
      by hardware (i.e by setting ZLT=1 for endpoint 0) and let software (UDC driver)
      handle the ZLP generation based on req->zero field.
      Signed-off-by: default avatarAbbas Raza <Abbas_Raza@mentor.com>
      Signed-off-by: default avatarPeter Chen <peter.chen@freescale.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1a24f220