[PATCH 4.9 00/33] 4.9.116-stable review

[PATCH 4.9 00/33] 4.9.116-stable review

[Greg Kroah-Hartman]

This is the start of the stable review cycle for the 4.9.116 release.
There are 33 patches in this series, all will be posted as a response
to this one.  If anyone has any issues with these being applied, please
let me know.

Responses should be made by Sun Jul 29 10:08:17 UTC 2018.
Anything received after that time might be too late.

The whole patch series can be found in one patch at:
	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.116-rc1.gz
or in the git tree and branch at:
	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Linux 4.9.116-rc1

Arnd Bergmann <arnd@arndb.de>
    exec: avoid gcc-8 warning for get_task_comm

Arnd Bergmann <arnd@arndb.de>
    turn off -Wattribute-alias

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix RX overflow interrupt not being enabled

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix incorrect clear of non-processed interrupts

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: keep only 1-2 frames in TX FIFO to fix TX accounting

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix device dropping off bus on RX overrun

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix recovery from error states not being propagated

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix power management handling

Anssi Hannula <anssi.hannula@bitwise.fi>
    can: xilinx_can: fix RX loop if RXNEMP is asserted without RXOK

Rafael J. Wysocki <rafael.j.wysocki@intel.com>
    driver core: Partially revert "driver core: correct device's shutdown order"

Jerry Zhang <zhangjerry@google.com>
    usb: gadget: f_fs: Only return delayed status when len is 0

Bin Liu <b-liu@ti.com>
    usb: core: handle hub C_PORT_OVER_CURRENT condition

Lubomir Rintel <lkundrak@v3.sk>
    usb: cdc_acm: Add quirk for Castles VEGA3000

Eric Dumazet <edumazet@google.com>
    tcp: call tcp_drop() from tcp_data_queue_ofo()

Eric Dumazet <edumazet@google.com>
    tcp: detect malicious patterns in tcp_collapse_ofo_queue()

Eric Dumazet <edumazet@google.com>
    tcp: avoid collapses in tcp_prune_queue() if possible

Eric Dumazet <edumazet@google.com>
    tcp: free batches of packets in tcp_prune_ofo_queue()

Yuchung Cheng <ycheng@google.com>
    tcp: do not delay ACK in DCTCP upon CE status change

Yuchung Cheng <ycheng@google.com>
    tcp: do not cancel delay-AcK on DCTCP special ACK

Yuchung Cheng <ycheng@google.com>
    tcp: helpers to send special DCTCP ack

Yuchung Cheng <ycheng@google.com>
    tcp: fix dctcp delayed ACK schedule

Roopa Prabhu <roopa@cumulusnetworks.com>
    rtnetlink: add rtnl_link_state check in rtnl_configure_link

Heiner Kallweit <hkallweit1@gmail.com>
    net: phy: consider PHY_IGNORE_INTERRUPT in phy_start_aneg_priv

Hangbin Liu <liuhangbin@gmail.com>
    multicast: do not restore deleted record source filter mode to new one

Eran Ben Elisha <eranbe@mellanox.com>
    net/mlx5e: Fix quota counting in aRFS expire flow

Eran Ben Elisha <eranbe@mellanox.com>
    net/mlx5e: Don't allow aRFS for encapsulated packets

Ariel Levkovich <lariel@mellanox.com>
    net/mlx5: Adjust clock overflow work period

Eric Dumazet <edumazet@google.com>
    net: skb_segment() should not return NULL

Jack Morgenstein <jackm@dev.mellanox.co.il>
    net/mlx4_core: Save the qpn from the input modifier in RST2INIT wrapper

Willem de Bruijn <willemb@google.com>
    ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull

Paolo Abeni <pabeni@redhat.com>
    ip: hash fragments consistently

Paul Burton <paul.burton@mips.com>
    MIPS: Fix off-by-one in pci_resource_to_user()

Felix Fietkau <nbd@nbd.name>
    MIPS: ath79: fix register address in ath79_ddr_wb_flush()


-------------

Diffstat:

 Makefile                                           |   5 +-
 arch/mips/ath79/common.c                           |   2 +-
 arch/mips/pci/pci.c                                |   2 +-
 drivers/base/dd.c                                  |   8 -
 drivers/net/can/xilinx_can.c                       | 392 +++++++++++++++------
 .../net/ethernet/mellanox/mlx4/resource_tracker.c  |   2 +-
 drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c  |   7 +-
 drivers/net/ethernet/mellanox/mlx5/core/en_clock.c |  12 +-
 drivers/net/phy/phy.c                              |   2 +-
 drivers/usb/class/cdc-acm.c                        |   3 +
 drivers/usb/core/hub.c                             |   8 +-
 drivers/usb/gadget/function/f_fs.c                 |   2 +-
 fs/exec.c                                          |   7 +-
 include/linux/sched.h                              |   6 +-
 include/linux/skbuff.h                             |   2 +
 include/net/tcp.h                                  |   2 +
 net/core/rtnetlink.c                               |   9 +-
 net/core/skbuff.c                                  |  10 +-
 net/ipv4/igmp.c                                    |   3 +-
 net/ipv4/ip_output.c                               |   2 +
 net/ipv4/ip_sockglue.c                             |   7 +-
 net/ipv4/tcp_dctcp.c                               |  50 +--
 net/ipv4/tcp_input.c                               |  40 ++-
 net/ipv4/tcp_output.c                              |  33 +-
 net/ipv6/datagram.c                                |   7 +-
 net/ipv6/ip6_output.c                              |   2 +
 net/ipv6/mcast.c                                   |   3 +-
 27 files changed, 431 insertions(+), 197 deletions(-)

[PATCH 4.9 01/33] MIPS: ath79: fix register address in ath79_ddr_wb_flush()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Felix Fietkau <nbd@nbd.name>

commit bc88ad2efd11f29e00a4fd60fcd1887abfe76833 upstream.

ath79_ddr_wb_flush_base has the type void __iomem *, so register offsets
need to be a multiple of 4 in order to access the intended register.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 24b0e3e84fbf ("MIPS: ath79: Improve the DDR controller interface")
Patchwork: https://patchwork.linux-mips.org/patch/19912/
Cc: Alban Bedel <albeu@free.fr>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/ath79/common.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/ath79/common.c
+++ b/arch/mips/ath79/common.c
@@ -58,7 +58,7 @@ EXPORT_SYMBOL_GPL(ath79_ddr_ctrl_init);
 
 void ath79_ddr_wb_flush(u32 reg)
 {
-	void __iomem *flush_reg = ath79_ddr_wb_flush_base + reg;
+	void __iomem *flush_reg = ath79_ddr_wb_flush_base + (reg * 4);
 
 	/* Flush the DDR write buffer. */
 	__raw_writel(0x1, flush_reg);

[PATCH 4.9 02/33] MIPS: Fix off-by-one in pci_resource_to_user()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paul Burton <paul.burton@mips.com>

commit 38c0a74fe06da3be133cae3fb7bde6a9438e698b upstream.

The MIPS implementation of pci_resource_to_user() introduced in v3.12 by
commit 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci
memory space properly") incorrectly sets *end to the address of the
byte after the resource, rather than the last byte of the resource.

This results in userland seeing resources as a byte larger than they
actually are, for example a 32 byte BAR will be reported by a tool such
as lspci as being 33 bytes in size:

    Region 2: I/O ports at 1000 [disabled] [size=33]

Correct this by subtracting one from the calculated end address,
reporting the correct address to userland.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Reported-by: Rui Wang <rui.wang@windriver.com>
Fixes: 4c2924b725fb ("MIPS: PCI: Use pci_resource_to_user to map pci memory space properly")
Cc: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org # v3.12+
Patchwork: https://patchwork.linux-mips.org/patch/19829/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/pci/pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -55,7 +55,7 @@ void pci_resource_to_user(const struct p
 	phys_addr_t size = resource_size(rsrc);
 
 	*start = fixup_bigphys_addr(rsrc->start, size);
-	*end = rsrc->start + size;
+	*end = rsrc->start + size - 1;
 }
 
 int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,

[PATCH 4.9 03/33] ip: hash fragments consistently

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Paolo Abeni <pabeni@redhat.com>

[ Upstream commit 3dd1c9a1270736029ffca670e9bd0265f4120600 ]

The skb hash for locally generated ip[v6] fragments belonging
to the same datagram can vary in several circumstances:
* for connected UDP[v6] sockets, the first fragment get its hash
  via set_owner_w()/skb_set_hash_from_sk()
* for unconnected IPv6 UDPv6 sockets, the first fragment can get
  its hash via ip6_make_flowlabel()/skb_get_hash_flowi6(), if
  auto_flowlabel is enabled

For the following frags the hash is usually computed via
skb_get_hash().
The above can cause OoO for unconnected IPv6 UDPv6 socket: in that
scenario the egress tx queue can be selected on a per packet basis
via the skb hash.
It may also fool flow-oriented schedulers to place fragments belonging
to the same datagram in different flows.

Fix the issue by copying the skb hash from the head frag into
the others at fragmentation time.

Before this commit:
perf probe -a "dev_queue_xmit skb skb->hash skb->l4_hash:b1@0/8 skb->sw_hash:b1@1/8"
netperf -H $IPV4 -t UDP_STREAM -l 5 -- -m 2000 -n &
perf record -e probe:dev_queue_xmit -e probe:skb_set_owner_w -a sleep 0.1
perf script
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=3713014309 l4_hash=1 sw_hash=0
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=0 l4_hash=0 sw_hash=0

After this commit:
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0

Fixes: b73c3d0e4f0e ("net: Save TX flow hash in sock and set in skbuf on xmit")
Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/ip_output.c  |    2 ++
 net/ipv6/ip6_output.c |    2 ++
 2 files changed, 4 insertions(+)

--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -497,6 +497,8 @@ static void ip_copy_metadata(struct sk_b
 	to->dev = from->dev;
 	to->mark = from->mark;
 
+	skb_copy_hash(to, from);
+
 	/* Copy the flags to each fragment. */
 	IPCB(to)->flags = IPCB(from)->flags;
 
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -576,6 +576,8 @@ static void ip6_copy_metadata(struct sk_
 	to->dev = from->dev;
 	to->mark = from->mark;
 
+	skb_copy_hash(to, from);
+
 #ifdef CONFIG_NET_SCHED
 	to->tc_index = from->tc_index;
 #endif

[PATCH 4.9 04/33] ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Willem de Bruijn <willemb@google.com>

[ Upstream commit 2efd4fca703a6707cad16ab486eaab8fc7f0fd49 ]

Syzbot reported a read beyond the end of the skb head when returning
IPV6_ORIGDSTADDR:

  BUG: KMSAN: kernel-infoleak in put_cmsg+0x5ef/0x860 net/core/scm.c:242
  CPU: 0 PID: 4501 Comm: syz-executor128 Not tainted 4.17.0+ #9
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
  Google 01/01/2011
  Call Trace:
    __dump_stack lib/dump_stack.c:77 [inline]
    dump_stack+0x185/0x1d0 lib/dump_stack.c:113
    kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
    kmsan_internal_check_memory+0x138/0x1f0 mm/kmsan/kmsan.c:1219
    kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1261
    copy_to_user include/linux/uaccess.h:184 [inline]
    put_cmsg+0x5ef/0x860 net/core/scm.c:242
    ip6_datagram_recv_specific_ctl+0x1cf3/0x1eb0 net/ipv6/datagram.c:719
    ip6_datagram_recv_ctl+0x41c/0x450 net/ipv6/datagram.c:733
    rawv6_recvmsg+0x10fb/0x1460 net/ipv6/raw.c:521
    [..]

This logic and its ipv4 counterpart read the destination port from
the packet at skb_transport_offset(skb) + 4.

With MSG_MORE and a local SOCK_RAW sender, syzbot was able to cook a
packet that stores headers exactly up to skb_transport_offset(skb) in
the head and the remainder in a frag.

Call pskb_may_pull before accessing the pointer to ensure that it lies
in skb head.

Link: http://lkml.kernel.org/r/CAF=yD-LEJwZj5a1-bAAj2Oy_hKmGygV6rsJ_WOrAYnv-fnayiQ@mail.gmail.com
Reported-by: syzbot+9adb4b567003cac781f0@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/ip_sockglue.c |    7 +++++--
 net/ipv6/datagram.c    |    7 +++++--
 2 files changed, 10 insertions(+), 4 deletions(-)

--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -135,15 +135,18 @@ static void ip_cmsg_recv_dstaddr(struct
 {
 	struct sockaddr_in sin;
 	const struct iphdr *iph = ip_hdr(skb);
-	__be16 *ports = (__be16 *)skb_transport_header(skb);
+	__be16 *ports;
+	int end;
 
-	if (skb_transport_offset(skb) + 4 > (int)skb->len)
+	end = skb_transport_offset(skb) + 4;
+	if (end > 0 && !pskb_may_pull(skb, end))
 		return;
 
 	/* All current transport protocols have the port numbers in the
 	 * first four bytes of the transport header and this function is
 	 * written with this assumption in mind.
 	 */
+	ports = (__be16 *)skb_transport_header(skb);
 
 	sin.sin_family = AF_INET;
 	sin.sin_addr.s_addr = iph->daddr;
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -694,13 +694,16 @@ void ip6_datagram_recv_specific_ctl(stru
 	}
 	if (np->rxopt.bits.rxorigdstaddr) {
 		struct sockaddr_in6 sin6;
-		__be16 *ports = (__be16 *) skb_transport_header(skb);
+		__be16 *ports;
+		int end;
 
-		if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
+		end = skb_transport_offset(skb) + 4;
+		if (end <= 0 || pskb_may_pull(skb, end)) {
 			/* All current transport protocols have the port numbers in the
 			 * first four bytes of the transport header and this function is
 			 * written with this assumption in mind.
 			 */
+			ports = (__be16 *)skb_transport_header(skb);
 
 			sin6.sin6_family = AF_INET6;
 			sin6.sin6_addr = ipv6_hdr(skb)->daddr;

[PATCH 4.9 05/33] net/mlx4_core: Save the qpn from the input modifier in RST2INIT wrapper

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jack Morgenstein <jackm@dev.mellanox.co.il>

[ Upstream commit 958c696f5a7274d9447a458ad7aa70719b29a50a ]

Function mlx4_RST2INIT_QP_wrapper saved the qp number passed in the qp
context, rather than the one passed in the input modifier.

However, the qp number in the qp context is not defined as a
required parameter by the FW. Therefore, drivers may choose to not
specify the qp number in the qp context for the reset-to-init transition.

Thus, we must save the qp number passed in the command input modifier --
which is always present. (This saved qp number is used as the input
modifier for command 2RST_QP when a slave's qp's are destroyed).

Fixes: c82e9aa0a8bc ("mlx4_core: resource tracking for HCA resources used by guests")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx4/resource_tracker.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
+++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
@@ -2916,7 +2916,7 @@ int mlx4_RST2INIT_QP_wrapper(struct mlx4
 	u32 srqn = qp_get_srqn(qpc) & 0xffffff;
 	int use_srq = (qp_get_srqn(qpc) >> 24) & 1;
 	struct res_srq *srq;
-	int local_qpn = be32_to_cpu(qpc->local_qpn) & 0xffffff;
+	int local_qpn = vhcr->in_modifier & 0xffffff;
 
 	err = adjust_qp_sched_queue(dev, slave, qpc, inbox);
 	if (err)

[PATCH 4.9 06/33] net: skb_segment() should not return NULL

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit ff907a11a0d68a749ce1a321f4505c03bf72190c ]

syzbot caught a NULL deref [1], caused by skb_segment()

skb_segment() has many "goto err;" that assume the @err variable
contains -ENOMEM.

A successful call to __skb_linearize() should not clear @err,
otherwise a subsequent memory allocation error could return NULL.

While we are at it, we might use -EINVAL instead of -ENOMEM when
MAX_SKB_FRAGS limit is reached.

[1]
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 0 PID: 13285 Comm: syz-executor3 Not tainted 4.18.0-rc4+ #146
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_gso_segment+0x3dc/0x1780 net/ipv4/tcp_offload.c:106
Code: f0 ff ff 0f 87 1c fd ff ff e8 00 88 0b fb 48 8b 75 d0 48 b9 00 00 00 00 00 fc ff df 48 8d be 90 00 00 00 48 89 f8 48 c1 e8 03 <0f> b6 14 08 48 8d 86 94 00 00 00 48 89 c6 83 e0 07 48 c1 ee 03 0f
RSP: 0018:ffff88019b7fd060 EFLAGS: 00010206
RAX: 0000000000000012 RBX: 0000000000000020 RCX: dffffc0000000000
RDX: 0000000000040000 RSI: 0000000000000000 RDI: 0000000000000090
RBP: ffff88019b7fd0f0 R08: ffff88019510e0c0 R09: ffffed003b5c46d6
R10: ffffed003b5c46d6 R11: ffff8801dae236b3 R12: 0000000000000001
R13: ffff8801d6c581f4 R14: 0000000000000000 R15: ffff8801d6c58128
FS:  00007fcae64d6700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004e8664 CR3: 00000001b669b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp4_gso_segment+0x1c3/0x440 net/ipv4/tcp_offload.c:54
 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342
 inet_gso_segment+0x64e/0x12d0 net/ipv4/af_inet.c:1342
 skb_mac_gso_segment+0x3b5/0x740 net/core/dev.c:2792
 __skb_gso_segment+0x3c3/0x880 net/core/dev.c:2865
 skb_gso_segment include/linux/netdevice.h:4099 [inline]
 validate_xmit_skb+0x640/0xf30 net/core/dev.c:3104
 __dev_queue_xmit+0xc14/0x3910 net/core/dev.c:3561
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602
 neigh_hh_output include/net/neighbour.h:473 [inline]
 neigh_output include/net/neighbour.h:481 [inline]
 ip_finish_output2+0x1063/0x1860 net/ipv4/ip_output.c:229
 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x223/0x880 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 iptunnel_xmit+0x567/0x850 net/ipv4/ip_tunnel_core.c:91
 ip_tunnel_xmit+0x1598/0x3af1 net/ipv4/ip_tunnel.c:778
 ipip_tunnel_xmit+0x264/0x2c0 net/ipv4/ipip.c:308
 __netdev_start_xmit include/linux/netdevice.h:4148 [inline]
 netdev_start_xmit include/linux/netdevice.h:4157 [inline]
 xmit_one net/core/dev.c:3034 [inline]
 dev_hard_start_xmit+0x26c/0xc30 net/core/dev.c:3050
 __dev_queue_xmit+0x29ef/0x3910 net/core/dev.c:3569
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3602
 neigh_direct_output+0x15/0x20 net/core/neighbour.c:1403
 neigh_output include/net/neighbour.h:483 [inline]
 ip_finish_output2+0xa67/0x1860 net/ipv4/ip_output.c:229
 ip_finish_output+0x841/0xfa0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x223/0x880 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0xc5/0x1b0 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x9df/0x1f80 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1bf9/0x3f10 net/ipv4/tcp_output.c:1168
 tcp_write_xmit+0x1641/0x5c20 net/ipv4/tcp_output.c:2363
 __tcp_push_pending_frames+0xb2/0x290 net/ipv4/tcp_output.c:2536
 tcp_push+0x638/0x8c0 net/ipv4/tcp.c:735
 tcp_sendmsg_locked+0x2ec5/0x3f00 net/ipv4/tcp.c:1410
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1447
 inet_sendmsg+0x1a1/0x690 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:641 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:651
 __sys_sendto+0x3d7/0x670 net/socket.c:1797
 __do_sys_sendto net/socket.c:1809 [inline]
 __se_sys_sendto net/socket.c:1805 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1805
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455ab9
Code: 1d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb b9 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fcae64d5c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcae64d66d4 RCX: 0000000000455ab9
RDX: 0000000000000001 RSI: 0000000020000200 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000014
R13: 00000000004c1145 R14: 00000000004d1818 R15: 0000000000000006
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)

Fixes: ddff00d42043 ("net: Move skb_has_shared_frag check out of GRE code and into segmentation")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/core/skbuff.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3253,6 +3253,7 @@ normal:
 				net_warn_ratelimited(
 					"skb_segment: too many frags: %u %u\n",
 					pos, mss);
+				err = -EINVAL;
 				goto err;
 			}
 
@@ -3289,11 +3290,10 @@ skip_fraglist:
 
 perform_csum_check:
 		if (!csum) {
-			if (skb_has_shared_frag(nskb)) {
-				err = __skb_linearize(nskb);
-				if (err)
-					goto err;
-			}
+			if (skb_has_shared_frag(nskb) &&
+			    __skb_linearize(nskb))
+				goto err;
+
 			if (!nskb->remcsum_offload)
 				nskb->ip_summed = CHECKSUM_NONE;
 			SKB_GSO_CB(nskb)->csum =

[PATCH 4.9 07/33] net/mlx5: Adjust clock overflow work period

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ariel Levkovich <lariel@mellanox.com>

[ Upstream commit 33180bee86a8940a84950edca46315cd9dd6deb5 ]

When driver converts HW timestamp to wall clock time it subtracts
the last saved cycle counter from the HW timestamp and converts the
difference to nanoseconds.
The conversion is done by multiplying the cycles difference with the
clock multiplier value as a first step and therefore the cycles
difference should be small enough so that the multiplication product
doesn't exceed 64bit.

The overflow handling routine is in charge of updating the last saved
cycle counter in driver and it is called periodically using kernel
delayed workqueue.

The delay period for this work is calculated using the max HW cycle
counter value (a 41 bit mask) as a base which doesn't take the 64bit
limit into account so the delay period may be incorrect and too
long to prevent a large difference between the HW counter and the last
saved counter in SW.

This change adjusts the work period for the HW clock overflow work by
taking the minimum between the previous value and the quotient of max
u64 value and the clock multiplier value.

Fixes: ef9814deafd0 ("net/mlx5e: Add HW timestamping (TS) support")
Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Reviewed-by: Eran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_clock.c |   12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
@@ -233,6 +233,7 @@ static void mlx5e_timestamp_init_config(
 void mlx5e_timestamp_init(struct mlx5e_priv *priv)
 {
 	struct mlx5e_tstamp *tstamp = &priv->tstamp;
+	u64 overflow_cycles;
 	u64 ns;
 	u64 frac = 0;
 	u32 dev_freq;
@@ -257,10 +258,17 @@ void mlx5e_timestamp_init(struct mlx5e_p
 
 	/* Calculate period in seconds to call the overflow watchdog - to make
 	 * sure counter is checked at least once every wrap around.
+	 * The period is calculated as the minimum between max HW cycles count
+	 * (The clock source mask) and max amount of cycles that can be
+	 * multiplied by clock multiplier where the result doesn't exceed
+	 * 64bits.
 	 */
-	ns = cyclecounter_cyc2ns(&tstamp->cycles, tstamp->cycles.mask,
+	overflow_cycles = div64_u64(~0ULL >> 1, tstamp->cycles.mult);
+	overflow_cycles = min(overflow_cycles, tstamp->cycles.mask >> 1);
+
+	ns = cyclecounter_cyc2ns(&tstamp->cycles, overflow_cycles,
 				 frac, &frac);
-	do_div(ns, NSEC_PER_SEC / 2 / HZ);
+	do_div(ns, NSEC_PER_SEC / HZ);
 	tstamp->overflow_period = ns;
 
 	INIT_DELAYED_WORK(&tstamp->overflow_work, mlx5e_timestamp_overflow);

[PATCH 4.9 08/33] net/mlx5e: Dont allow aRFS for encapsulated packets

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eran Ben Elisha <eranbe@mellanox.com>

[ Upstream commit d2e1c57bcf9a07cbb67f30ecf238f298799bce1c ]

Driver is yet to support aRFS for encapsulated packets, return early
error in such case.

Fixes: 18c908e477dc ("net/mlx5e: Add accelerated RFS support")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c
@@ -715,6 +715,9 @@ int mlx5e_rx_flow_steer(struct net_devic
 	    skb->protocol != htons(ETH_P_IPV6))
 		return -EPROTONOSUPPORT;
 
+	if (skb->encapsulation)
+		return -EPROTONOSUPPORT;
+
 	arfs_t = arfs_get_table(arfs, arfs_get_ip_proto(skb), skb->protocol);
 	if (!arfs_t)
 		return -EPROTONOSUPPORT;

[PATCH 4.9 09/33] net/mlx5e: Fix quota counting in aRFS expire flow

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eran Ben Elisha <eranbe@mellanox.com>

[ Upstream commit 2630bae8018823c3b88788b69fb9f16ea3b4a11e ]

Quota should follow the amount of rules which do expire, and not the
number of rules that were examined, fixed that.

Fixes: 18c908e477dc ("net/mlx5e: Add accelerated RFS support")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_arfs.c
@@ -383,14 +383,14 @@ static void arfs_may_expire_flow(struct
 	HLIST_HEAD(del_list);
 	spin_lock_bh(&priv->fs.arfs.arfs_lock);
 	mlx5e_for_each_arfs_rule(arfs_rule, htmp, priv->fs.arfs.arfs_tables, i, j) {
-		if (quota++ > MLX5E_ARFS_EXPIRY_QUOTA)
-			break;
 		if (!work_pending(&arfs_rule->arfs_work) &&
 		    rps_may_expire_flow(priv->netdev,
 					arfs_rule->rxq, arfs_rule->flow_id,
 					arfs_rule->filter_id)) {
 			hlist_del_init(&arfs_rule->hlist);
 			hlist_add_head(&arfs_rule->hlist, &del_list);
+			if (quota++ > MLX5E_ARFS_EXPIRY_QUOTA)
+				break;
 		}
 	}
 	spin_unlock_bh(&priv->fs.arfs.arfs_lock);

[PATCH 4.9 10/33] multicast: do not restore deleted record source filter mode to new one

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hangbin Liu <liuhangbin@gmail.com>

There are two scenarios that we will restore deleted records. The first is
when device down and up(or unmap/remap). In this scenario the new filter
mode is same with previous one. Because we get it from in_dev->mc_list and
we do not touch it during device down and up.

The other scenario is when a new socket join a group which was just delete
and not finish sending status reports. In this scenario, we should use the
current filter mode instead of restore old one. Here are 4 cases in total.

old_socket        new_socket       before_fix       after_fix
  IN(A)             IN(A)           ALLOW(A)         ALLOW(A)
  IN(A)             EX( )           TO_IN( )         TO_EX( )
  EX( )             IN(A)           TO_EX( )         ALLOW(A)
  EX( )             EX( )           TO_EX( )         TO_EX( )

Fixes: 24803f38a5c0b (igmp: do not remove igmp souce list info when set link down)
Fixes: 1666d49e1d416 (mld: do not remove mld souce list info when set link down)
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/igmp.c  |    3 +--
 net/ipv6/mcast.c |    3 +--
 2 files changed, 2 insertions(+), 4 deletions(-)

--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1193,8 +1193,7 @@ static void igmpv3_del_delrec(struct in_
 	if (pmc) {
 		im->interface = pmc->interface;
 		im->crcount = in_dev->mr_qrv ?: net->ipv4.sysctl_igmp_qrv;
-		im->sfmode = pmc->sfmode;
-		if (pmc->sfmode == MCAST_INCLUDE) {
+		if (im->sfmode == MCAST_INCLUDE) {
 			im->tomb = pmc->tomb;
 			im->sources = pmc->sources;
 			for (psf = im->sources; psf; psf = psf->sf_next)
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -771,8 +771,7 @@ static void mld_del_delrec(struct inet6_
 	if (pmc) {
 		im->idev = pmc->idev;
 		im->mca_crcount = idev->mc_qrv;
-		im->mca_sfmode = pmc->mca_sfmode;
-		if (pmc->mca_sfmode == MCAST_INCLUDE) {
+		if (im->mca_sfmode == MCAST_INCLUDE) {
 			im->mca_tomb = pmc->mca_tomb;
 			im->mca_sources = pmc->mca_sources;
 			for (psf = im->mca_sources; psf; psf = psf->sf_next)

[PATCH 4.9 11/33] net: phy: consider PHY_IGNORE_INTERRUPT in phy_start_aneg_priv

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Heiner Kallweit <hkallweit1@gmail.com>

[ Upstream commit 215d08a85b9acf5e1fe9dbf50f1774cde333efef ]

The situation described in the comment can occur also with
PHY_IGNORE_INTERRUPT, therefore change the condition to include it.

Fixes: f555f34fdc58 ("net: phy: fix auto-negotiation stall due to unavailable interrupt")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/phy/phy.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -598,7 +598,7 @@ static int phy_start_aneg_priv(struct ph
 	 * negotiation may already be done and aneg interrupt may not be
 	 * generated.
 	 */
-	if (phy_interrupt_is_valid(phydev) && (phydev->state == PHY_AN)) {
+	if (phydev->irq != PHY_POLL && phydev->state == PHY_AN) {
 		err = phy_aneg_done(phydev);
 		if (err > 0) {
 			trigger = true;

[PATCH 4.9 12/33] rtnetlink: add rtnl_link_state check in rtnl_configure_link

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Roopa Prabhu <roopa@cumulusnetworks.com>

[ Upstream commit 5025f7f7d506fba9b39e7fe8ca10f6f34cb9bc2d ]

rtnl_configure_link sets dev->rtnl_link_state to
RTNL_LINK_INITIALIZED and unconditionally calls
__dev_notify_flags to notify user-space of dev flags.

current call sequence for rtnl_configure_link
rtnetlink_newlink
    rtnl_link_ops->newlink
    rtnl_configure_link (unconditionally notifies userspace of
                         default and new dev flags)

If a newlink handler wants to call rtnl_configure_link
early, we will end up with duplicate notifications to
user-space.

This patch fixes rtnl_configure_link to check rtnl_link_state
and call __dev_notify_flags with gchanges = 0 if already
RTNL_LINK_INITIALIZED.

Later in the series, this patch will help the following sequence
where a driver implementing newlink can call rtnl_configure_link
to initialize the link early.

makes the following call sequence work:
rtnetlink_newlink
    rtnl_link_ops->newlink (vxlan) -> rtnl_configure_link (initializes
                                                link and notifies
                                                user-space of default
                                                dev flags)
    rtnl_configure_link (updates dev flags if requested by user ifm
                         and notifies user-space of new dev flags)

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/core/rtnetlink.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2339,9 +2339,12 @@ int rtnl_configure_link(struct net_devic
 			return err;
 	}
 
-	dev->rtnl_link_state = RTNL_LINK_INITIALIZED;
-
-	__dev_notify_flags(dev, old_flags, ~0U);
+	if (dev->rtnl_link_state == RTNL_LINK_INITIALIZED) {
+		__dev_notify_flags(dev, old_flags, 0U);
+	} else {
+		dev->rtnl_link_state = RTNL_LINK_INITIALIZED;
+		__dev_notify_flags(dev, old_flags, ~0U);
+	}
 	return 0;
 }
 EXPORT_SYMBOL(rtnl_configure_link);

[PATCH 4.9 13/33] tcp: fix dctcp delayed ACK schedule

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yuchung Cheng <ycheng@google.com>

[ Upstream commit b0c05d0e99d98d7f0cd41efc1eeec94efdc3325d ]

Previously, when a data segment was sent an ACK was piggybacked
on the data segment without generating a CA_EVENT_NON_DELAYED_ACK
event to notify congestion control modules. So the DCTCP
ca->delayed_ack_reserved flag could incorrectly stay set when
in fact there were no delayed ACKs being reserved. This could result
in sending a special ECN notification ACK that carries an older
ACK sequence, when in fact there was no need for such an ACK.
DCTCP keeps track of the delayed ACK status with its own separate
state ca->delayed_ack_reserved. Previously it may accidentally cancel
the delayed ACK without updating this field upon sending a special
ACK that carries a older ACK sequence. This inconsistency would
lead to DCTCP receiver never acknowledging the latest data until the
sender times out and retry in some cases.

Packetdrill script (provided by Larry Brakmo)

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 setsockopt(3, SOL_TCP, TCP_CONGESTION, "dctcp", 5) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0

0.100 < [ect0] SEW 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>
0.100 > SE. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
0.110 < [ect0] . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4

0.200 < [ect0] . 1:1001(1000) ack 1 win 257
0.200 > [ect01] . 1:1(0) ack 1001

0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 1:2(1) ack 1001

0.200 < [ect0] . 1001:2001(1000) ack 2 win 257
0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 2:3(1) ack 2001

0.200 < [ect0] . 2001:3001(1000) ack 3 win 257
0.200 < [ect0] . 3001:4001(1000) ack 3 win 257
0.200 > [ect01] . 3:3(0) ack 4001

0.210 < [ce] P. 4001:4501(500) ack 3 win 257

+0.001 read(4, ..., 4500) = 4500
+0 write(4, ..., 1) = 1
+0 > [ect01] PE. 3:4(1) ack 4501

+0.010 < [ect0] W. 4501:5501(1000) ack 4 win 257
// Previously the ACK sequence below would be 4501, causing a long RTO
+0.040~+0.045 > [ect01] . 4:4(0) ack 5501   // delayed ack

+0.311 < [ect0] . 5501:6501(1000) ack 4 win 257  // More data
+0 > [ect01] . 4:4(0) ack 6501     // now acks everything

+0.500 < F. 9501:9501(0) ack 4 win 257

Reported-by: Larry Brakmo <brakmo@fb.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_dctcp.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -134,7 +134,8 @@ static void dctcp_ce_state_0_to_1(struct
 	/* State has changed from CE=0 to CE=1 and delayed
 	 * ACK has not sent yet.
 	 */
-	if (!ca->ce_state && ca->delayed_ack_reserved) {
+	if (!ca->ce_state &&
+	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
 		u32 tmp_rcv_nxt;
 
 		/* Save current rcv_nxt. */
@@ -164,7 +165,8 @@ static void dctcp_ce_state_1_to_0(struct
 	/* State has changed from CE=1 to CE=0 and delayed
 	 * ACK has not sent yet.
 	 */
-	if (ca->ce_state && ca->delayed_ack_reserved) {
+	if (ca->ce_state &&
+	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
 		u32 tmp_rcv_nxt;
 
 		/* Save current rcv_nxt. */

[PATCH 4.9 14/33] tcp: helpers to send special DCTCP ack

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yuchung Cheng <ycheng@google.com>

[ Upstream commit 2987babb6982306509380fc11b450227a844493b ]

Refactor and create helpers to send the special ACK in DCTCP.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_output.c |   22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -905,8 +905,8 @@ out:
  * We are working here with either a clone of the original
  * SKB, or a fresh unique copy made by the retransmit engine.
  */
-static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
-			    gfp_t gfp_mask)
+static int __tcp_transmit_skb(struct sock *sk, struct sk_buff *skb,
+			      int clone_it, gfp_t gfp_mask, u32 rcv_nxt)
 {
 	const struct inet_connection_sock *icsk = inet_csk(sk);
 	struct inet_sock *inet;
@@ -969,7 +969,7 @@ static int tcp_transmit_skb(struct sock
 	th->source		= inet->inet_sport;
 	th->dest		= inet->inet_dport;
 	th->seq			= htonl(tcb->seq);
-	th->ack_seq		= htonl(tp->rcv_nxt);
+	th->ack_seq		= htonl(rcv_nxt);
 	*(((__be16 *)th) + 6)	= htons(((tcp_header_size >> 2) << 12) |
 					tcb->tcp_flags);
 
@@ -1046,6 +1046,13 @@ static int tcp_transmit_skb(struct sock
 	return err;
 }
 
+static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
+			    gfp_t gfp_mask)
+{
+	return __tcp_transmit_skb(sk, skb, clone_it, gfp_mask,
+				  tcp_sk(sk)->rcv_nxt);
+}
+
 /* This routine just queues the buffer for sending.
  *
  * NOTE: probe0 timer is not checked, do not forget tcp_push_pending_frames,
@@ -3482,7 +3489,7 @@ void tcp_send_delayed_ack(struct sock *s
 }
 
 /* This routine sends an ack and also updates the window. */
-void tcp_send_ack(struct sock *sk)
+void __tcp_send_ack(struct sock *sk, u32 rcv_nxt)
 {
 	struct sk_buff *buff;
 
@@ -3520,7 +3527,12 @@ void tcp_send_ack(struct sock *sk)
 
 	/* Send it off, this clears delayed acks for us. */
 	skb_mstamp_get(&buff->skb_mstamp);
-	tcp_transmit_skb(sk, buff, 0, (__force gfp_t)0);
+	__tcp_transmit_skb(sk, buff, 0, (__force gfp_t)0, rcv_nxt);
+}
+
+void tcp_send_ack(struct sock *sk)
+{
+	__tcp_send_ack(sk, tcp_sk(sk)->rcv_nxt);
 }
 EXPORT_SYMBOL_GPL(tcp_send_ack);
 

[PATCH 4.9 15/33] tcp: do not cancel delay-AcK on DCTCP special ACK

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yuchung Cheng <ycheng@google.com>

[ Upstream commit 27cde44a259c380a3c09066fc4b42de7dde9b1ad ]

Currently when a DCTCP receiver delays an ACK and receive a
data packet with a different CE mark from the previous one's, it
sends two immediate ACKs acking previous and latest sequences
respectly (for ECN accounting).

Previously sending the first ACK may mark off the delayed ACK timer
(tcp_event_ack_sent). This may subsequently prevent sending the
second ACK to acknowledge the latest sequence (tcp_ack_snd_check).
The culprit is that tcp_send_ack() assumes it always acknowleges
the latest sequence, which is not true for the first special ACK.

The fix is to not make the assumption in tcp_send_ack and check the
actual ack sequence before cancelling the delayed ACK. Further it's
safer to pass the ack sequence number as a local variable into
tcp_send_ack routine, instead of intercepting tp->rcv_nxt to avoid
future bugs like this.

Reported-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/net/tcp.h     |    1 +
 net/ipv4/tcp_dctcp.c  |   34 ++++------------------------------
 net/ipv4/tcp_output.c |   11 ++++++++---
 3 files changed, 13 insertions(+), 33 deletions(-)

--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -553,6 +553,7 @@ void tcp_send_fin(struct sock *sk);
 void tcp_send_active_reset(struct sock *sk, gfp_t priority);
 int tcp_send_synack(struct sock *);
 void tcp_push_one(struct sock *, unsigned int mss_now);
+void __tcp_send_ack(struct sock *sk, u32 rcv_nxt);
 void tcp_send_ack(struct sock *sk);
 void tcp_send_delayed_ack(struct sock *sk);
 void tcp_send_loss_probe(struct sock *sk);
--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -135,21 +135,8 @@ static void dctcp_ce_state_0_to_1(struct
 	 * ACK has not sent yet.
 	 */
 	if (!ca->ce_state &&
-	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
-		u32 tmp_rcv_nxt;
-
-		/* Save current rcv_nxt. */
-		tmp_rcv_nxt = tp->rcv_nxt;
-
-		/* Generate previous ack with CE=0. */
-		tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
-		tp->rcv_nxt = ca->prior_rcv_nxt;
-
-		tcp_send_ack(sk);
-
-		/* Recover current rcv_nxt. */
-		tp->rcv_nxt = tmp_rcv_nxt;
-	}
+	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+		__tcp_send_ack(sk, ca->prior_rcv_nxt);
 
 	ca->prior_rcv_nxt = tp->rcv_nxt;
 	ca->ce_state = 1;
@@ -166,21 +153,8 @@ static void dctcp_ce_state_1_to_0(struct
 	 * ACK has not sent yet.
 	 */
 	if (ca->ce_state &&
-	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER) {
-		u32 tmp_rcv_nxt;
-
-		/* Save current rcv_nxt. */
-		tmp_rcv_nxt = tp->rcv_nxt;
-
-		/* Generate previous ack with CE=1. */
-		tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
-		tp->rcv_nxt = ca->prior_rcv_nxt;
-
-		tcp_send_ack(sk);
-
-		/* Recover current rcv_nxt. */
-		tp->rcv_nxt = tmp_rcv_nxt;
-	}
+	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+		__tcp_send_ack(sk, ca->prior_rcv_nxt);
 
 	ca->prior_rcv_nxt = tp->rcv_nxt;
 	ca->ce_state = 0;
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -174,8 +174,13 @@ static void tcp_event_data_sent(struct t
 }
 
 /* Account for an ACK we sent. */
-static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts)
+static inline void tcp_event_ack_sent(struct sock *sk, unsigned int pkts,
+				      u32 rcv_nxt)
 {
+	struct tcp_sock *tp = tcp_sk(sk);
+
+	if (unlikely(rcv_nxt != tp->rcv_nxt))
+		return;  /* Special ACK sent by DCTCP to reflect ECN */
 	tcp_dec_quickack_mode(sk, pkts);
 	inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
 }
@@ -1010,7 +1015,7 @@ static int __tcp_transmit_skb(struct soc
 	icsk->icsk_af_ops->send_check(sk, skb);
 
 	if (likely(tcb->tcp_flags & TCPHDR_ACK))
-		tcp_event_ack_sent(sk, tcp_skb_pcount(skb));
+		tcp_event_ack_sent(sk, tcp_skb_pcount(skb), rcv_nxt);
 
 	if (skb->len != tcp_header_size) {
 		tcp_event_data_sent(tp, sk);
@@ -3529,12 +3534,12 @@ void __tcp_send_ack(struct sock *sk, u32
 	skb_mstamp_get(&buff->skb_mstamp);
 	__tcp_transmit_skb(sk, buff, 0, (__force gfp_t)0, rcv_nxt);
 }
+EXPORT_SYMBOL_GPL(__tcp_send_ack);
 
 void tcp_send_ack(struct sock *sk)
 {
 	__tcp_send_ack(sk, tcp_sk(sk)->rcv_nxt);
 }
-EXPORT_SYMBOL_GPL(tcp_send_ack);
 
 /* This routine sends a packet with an out of date sequence
  * number. It assumes the other end will try to ack it.

[PATCH 4.9 16/33] tcp: do not delay ACK in DCTCP upon CE status change

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yuchung Cheng <ycheng@google.com>

[ Upstream commit a0496ef2c23b3b180902dd185d0d63ccbc624cf8 ]

Per DCTCP RFC8257 (Section 3.2) the ACK reflecting the CE status change
has to be sent immediately so the sender can respond quickly:

""" When receiving packets, the CE codepoint MUST be processed as follows:

   1.  If the CE codepoint is set and DCTCP.CE is false, set DCTCP.CE to
       true and send an immediate ACK.

   2.  If the CE codepoint is not set and DCTCP.CE is true, set DCTCP.CE
       to false and send an immediate ACK.
"""

Previously DCTCP implementation may continue to delay the ACK. This
patch fixes that to implement the RFC by forcing an immediate ACK.

Tested with this packetdrill script provided by Larry Brakmo

0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
0.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
0.000 setsockopt(3, SOL_TCP, TCP_CONGESTION, "dctcp", 5) = 0
0.000 bind(3, ..., ...) = 0
0.000 listen(3, 1) = 0

0.100 < [ect0] SEW 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7>
0.100 > SE. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 8>
0.110 < [ect0] . 1:1(0) ack 1 win 257
0.200 accept(3, ..., ...) = 4
   +0 setsockopt(4, SOL_SOCKET, SO_DEBUG, [1], 4) = 0

0.200 < [ect0] . 1:1001(1000) ack 1 win 257
0.200 > [ect01] . 1:1(0) ack 1001

0.200 write(4, ..., 1) = 1
0.200 > [ect01] P. 1:2(1) ack 1001

0.200 < [ect0] . 1001:2001(1000) ack 2 win 257
+0.005 < [ce] . 2001:3001(1000) ack 2 win 257

+0.000 > [ect01] . 2:2(0) ack 2001
// Previously the ACK below would be delayed by 40ms
+0.000 > [ect01] E. 2:2(0) ack 3001

+0.500 < F. 9501:9501(0) ack 4 win 257

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/net/tcp.h    |    1 +
 net/ipv4/tcp_dctcp.c |   30 ++++++++++++++++++------------
 net/ipv4/tcp_input.c |    3 ++-
 3 files changed, 21 insertions(+), 13 deletions(-)

--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -363,6 +363,7 @@ ssize_t tcp_splice_read(struct socket *s
 			struct pipe_inode_info *pipe, size_t len,
 			unsigned int flags);
 
+void tcp_enter_quickack_mode(struct sock *sk);
 static inline void tcp_dec_quickack_mode(struct sock *sk,
 					 const unsigned int pkts)
 {
--- a/net/ipv4/tcp_dctcp.c
+++ b/net/ipv4/tcp_dctcp.c
@@ -131,12 +131,15 @@ static void dctcp_ce_state_0_to_1(struct
 	struct dctcp *ca = inet_csk_ca(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	/* State has changed from CE=0 to CE=1 and delayed
-	 * ACK has not sent yet.
-	 */
-	if (!ca->ce_state &&
-	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
-		__tcp_send_ack(sk, ca->prior_rcv_nxt);
+	if (!ca->ce_state) {
+		/* State has changed from CE=0 to CE=1, force an immediate
+		 * ACK to reflect the new CE state. If an ACK was delayed,
+		 * send that first to reflect the prior CE state.
+		 */
+		if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+			__tcp_send_ack(sk, ca->prior_rcv_nxt);
+		tcp_enter_quickack_mode(sk);
+	}
 
 	ca->prior_rcv_nxt = tp->rcv_nxt;
 	ca->ce_state = 1;
@@ -149,12 +152,15 @@ static void dctcp_ce_state_1_to_0(struct
 	struct dctcp *ca = inet_csk_ca(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	/* State has changed from CE=1 to CE=0 and delayed
-	 * ACK has not sent yet.
-	 */
-	if (ca->ce_state &&
-	    inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
-		__tcp_send_ack(sk, ca->prior_rcv_nxt);
+	if (ca->ce_state) {
+		/* State has changed from CE=1 to CE=0, force an immediate
+		 * ACK to reflect the new CE state. If an ACK was delayed,
+		 * send that first to reflect the prior CE state.
+		 */
+		if (inet_csk(sk)->icsk_ack.pending & ICSK_ACK_TIMER)
+			__tcp_send_ack(sk, ca->prior_rcv_nxt);
+		tcp_enter_quickack_mode(sk);
+	}
 
 	ca->prior_rcv_nxt = tp->rcv_nxt;
 	ca->ce_state = 0;
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -209,13 +209,14 @@ static void tcp_incr_quickack(struct soc
 		icsk->icsk_ack.quick = min(quickacks, TCP_MAX_QUICKACKS);
 }
 
-static void tcp_enter_quickack_mode(struct sock *sk)
+void tcp_enter_quickack_mode(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	tcp_incr_quickack(sk);
 	icsk->icsk_ack.pingpong = 0;
 	icsk->icsk_ack.ato = TCP_ATO_MIN;
 }
+EXPORT_SYMBOL(tcp_enter_quickack_mode);
 
 /* Send ACKs quickly, if "quick" count is not exhausted
  * and the session is not interactive.

[PATCH 4.9 17/33] tcp: free batches of packets in tcp_prune_ofo_queue()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 72cd43ba64fc172a443410ce01645895850844c8 ]

Juha-Matti Tilli reported that malicious peers could inject tiny
packets in out_of_order_queue, forcing very expensive calls
to tcp_collapse_ofo_queue() and tcp_prune_ofo_queue() for
every incoming packet. out_of_order_queue rb-tree can contain
thousands of nodes, iterating over all of them is not nice.

Before linux-4.9, we would have pruned all packets in ofo_queue
in one go, every XXXX packets. XXXX depends on sk_rcvbuf and skbs
truesize, but is about 7000 packets with tcp_rmem[2] default of 6 MB.

Since we plan to increase tcp_rmem[2] in the future to cope with
modern BDP, can not revert to the old behavior, without great pain.

Strategy taken in this patch is to purge ~12.5 % of the queue capacity.

Fixes: 36a6503fedda ("tcp: refine tcp_prune_ofo_queue() to not drop all packets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/skbuff.h |    2 ++
 net/ipv4/tcp_input.c   |   15 +++++++++++----
 2 files changed, 13 insertions(+), 4 deletions(-)

--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2982,6 +2982,8 @@ static inline int __skb_grow_rcsum(struc
 	return __skb_grow(skb, len);
 }
 
+#define rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode)
+
 #define skb_queue_walk(queue, skb) \
 		for (skb = (queue)->next;					\
 		     skb != (struct sk_buff *)(queue);				\
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4965,6 +4965,7 @@ new_range:
  * 2) not add too big latencies if thousands of packets sit there.
  *    (But if application shrinks SO_RCVBUF, we could still end up
  *     freeing whole queue here)
+ * 3) Drop at least 12.5 % of sk_rcvbuf to avoid malicious attacks.
  *
  * Return true if queue has shrunk.
  */
@@ -4972,20 +4973,26 @@ static bool tcp_prune_ofo_queue(struct s
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct rb_node *node, *prev;
+	int goal;
 
 	if (RB_EMPTY_ROOT(&tp->out_of_order_queue))
 		return false;
 
 	NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED);
+	goal = sk->sk_rcvbuf >> 3;
 	node = &tp->ooo_last_skb->rbnode;
 	do {
 		prev = rb_prev(node);
 		rb_erase(node, &tp->out_of_order_queue);
+		goal -= rb_to_skb(node)->truesize;
 		tcp_drop(sk, rb_entry(node, struct sk_buff, rbnode));
-		sk_mem_reclaim(sk);
-		if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
-		    !tcp_under_memory_pressure(sk))
-			break;
+		if (!prev || goal <= 0) {
+			sk_mem_reclaim(sk);
+			if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
+			    !tcp_under_memory_pressure(sk))
+				break;
+			goal = sk->sk_rcvbuf >> 3;
+		}
 		node = prev;
 	} while (node);
 	tp->ooo_last_skb = rb_entry(prev, struct sk_buff, rbnode);

[PATCH 4.9 18/33] tcp: avoid collapses in tcp_prune_queue() if possible

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit f4a3313d8e2ca9fd8d8f45e40a2903ba782607e7 ]

Right after a TCP flow is created, receiving tiny out of order
packets allways hit the condition :

if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
	tcp_clamp_window(sk);

tcp_clamp_window() increases sk_rcvbuf to match sk_rmem_alloc
(guarded by tcp_rmem[2])

Calling tcp_collapse_ofo_queue() in this case is not useful,
and offers a O(N^2) surface attack to malicious peers.

Better not attempt anything before full queue capacity is reached,
forcing attacker to spend lots of resource and allow us to more
easily detect the abuse.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_input.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5027,6 +5027,9 @@ static int tcp_prune_queue(struct sock *
 	else if (tcp_under_memory_pressure(sk))
 		tp->rcv_ssthresh = min(tp->rcv_ssthresh, 4U * tp->advmss);
 
+	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf)
+		return 0;
+
 	tcp_collapse_ofo_queue(sk);
 	if (!skb_queue_empty(&sk->sk_receive_queue))
 		tcp_collapse(sk, &sk->sk_receive_queue, NULL,

[PATCH 4.9 19/33] tcp: detect malicious patterns in tcp_collapse_ofo_queue()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 3d4bf93ac12003f9b8e1e2de37fe27983deebdcf ]

In case an attacker feeds tiny packets completely out of order,
tcp_collapse_ofo_queue() might scan the whole rb-tree, performing
expensive copies, but not changing socket memory usage at all.

1) Do not attempt to collapse tiny skbs.
2) Add logic to exit early when too many tiny skbs are detected.

We prefer not doing aggressive collapsing (which copies packets)
for pathological flows, and revert to tcp_prune_ofo_queue() which
will be less expensive.

In the future, we might add the possibility of terminating flows
that are proven to be malicious.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_input.c |   15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4918,6 +4918,7 @@ end:
 static void tcp_collapse_ofo_queue(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
+	u32 range_truesize, sum_tiny = 0;
 	struct sk_buff *skb, *head;
 	struct rb_node *p;
 	u32 start, end;
@@ -4936,6 +4937,7 @@ new_range:
 	}
 	start = TCP_SKB_CB(skb)->seq;
 	end = TCP_SKB_CB(skb)->end_seq;
+	range_truesize = skb->truesize;
 
 	for (head = skb;;) {
 		skb = tcp_skb_next(skb, NULL);
@@ -4946,11 +4948,20 @@ new_range:
 		if (!skb ||
 		    after(TCP_SKB_CB(skb)->seq, end) ||
 		    before(TCP_SKB_CB(skb)->end_seq, start)) {
-			tcp_collapse(sk, NULL, &tp->out_of_order_queue,
-				     head, skb, start, end);
+			/* Do not attempt collapsing tiny skbs */
+			if (range_truesize != head->truesize ||
+			    end - start >= SKB_WITH_OVERHEAD(SK_MEM_QUANTUM)) {
+				tcp_collapse(sk, NULL, &tp->out_of_order_queue,
+					     head, skb, start, end);
+			} else {
+				sum_tiny += range_truesize;
+				if (sum_tiny > sk->sk_rcvbuf >> 3)
+					return;
+			}
 			goto new_range;
 		}
 
+		range_truesize += skb->truesize;
 		if (unlikely(before(TCP_SKB_CB(skb)->seq, start)))
 			start = TCP_SKB_CB(skb)->seq;
 		if (after(TCP_SKB_CB(skb)->end_seq, end))

[PATCH 4.9 20/33] tcp: call tcp_drop() from tcp_data_queue_ofo()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 8541b21e781a22dce52a74fef0b9bed00404a1cd ]

In order to be able to give better diagnostics and detect
malicious traffic, we need to have better sk->sk_drops tracking.

Fixes: 9f5afeae5152 ("tcp: use an RB tree for ooo receive queue")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/ipv4/tcp_input.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4517,7 +4517,7 @@ coalesce_done:
 				/* All the bits are present. Drop. */
 				NET_INC_STATS(sock_net(sk),
 					      LINUX_MIB_TCPOFOMERGE);
-				__kfree_skb(skb);
+				tcp_drop(sk, skb);
 				skb = NULL;
 				tcp_dsack_set(sk, seq, end_seq);
 				goto add_sack;
@@ -4536,7 +4536,7 @@ coalesce_done:
 						 TCP_SKB_CB(skb1)->end_seq);
 				NET_INC_STATS(sock_net(sk),
 					      LINUX_MIB_TCPOFOMERGE);
-				__kfree_skb(skb1);
+				tcp_drop(sk, skb1);
 				goto merge_right;
 			}
 		} else if (tcp_try_coalesce(sk, skb1, skb, &fragstolen)) {

[PATCH 4.9 21/33] usb: cdc_acm: Add quirk for Castles VEGA3000

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Lubomir Rintel <lkundrak@v3.sk>

commit 1445cbe476fc3dd09c0b380b206526a49403c071 upstream.

The device (a POS terminal) implements CDC ACM, but has not union
descriptor.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/class/cdc-acm.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1785,6 +1785,9 @@ static const struct usb_device_id acm_id
 	{ USB_DEVICE(0x09d8, 0x0320), /* Elatec GmbH TWN3 */
 	.driver_info = NO_UNION_NORMAL, /* has misplaced union descriptor */
 	},
+	{ USB_DEVICE(0x0ca6, 0xa050), /* Castles VEGA3000 */
+	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
+	},
 
 	{ USB_DEVICE(0x2912, 0x0001), /* ATOL FPrint */
 	.driver_info = CLEAR_HALT_CONDITIONS,

[PATCH 4.9 22/33] usb: core: handle hub C_PORT_OVER_CURRENT condition

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Bin Liu <b-liu@ti.com>

commit 249a32b7eeb3edb6897dd38f89651a62163ac4ed upstream.

Based on USB2.0 Spec Section 11.12.5,

  "If a hub has per-port power switching and per-port current limiting,
  an over-current on one port may still cause the power on another port
  to fall below specific minimums. In this case, the affected port is
  placed in the Power-Off state and C_PORT_OVER_CURRENT is set for the
  port, but PORT_OVER_CURRENT is not set."

so let's check C_PORT_OVER_CURRENT too for over current condition.

Fixes: 08d1dec6f405 ("usb:hub set hub->change_bits when over-current happens")
Cc: <stable@vger.kernel.org>
Tested-by: Alessandro Antenucci <antenucci@korg.it>
Signed-off-by: Bin Liu <b-liu@ti.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/core/hub.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1139,10 +1139,14 @@ static void hub_activate(struct usb_hub
 
 		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
 			/* Tell hub_wq to disconnect the device or
-			 * check for a new connection
+			 * check for a new connection or over current condition.
+			 * Based on USB2.0 Spec Section 11.12.5,
+			 * C_PORT_OVER_CURRENT could be set while
+			 * PORT_OVER_CURRENT is not. So check for any of them.
 			 */
 			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
-			    (portstatus & USB_PORT_STAT_OVERCURRENT))
+			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
+			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
 				set_bit(port1, hub->change_bits);
 
 		} else if (portstatus & USB_PORT_STAT_ENABLE) {

[PATCH 4.9 23/33] usb: gadget: f_fs: Only return delayed status when len is 0

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jerry Zhang <zhangjerry@google.com>

commit 4d644abf25698362bd33d17c9ddc8f7122c30f17 upstream.

Commit 1b9ba000 ("Allow function drivers to pause control
transfers") states that USB_GADGET_DELAYED_STATUS is only
supported if data phase is 0 bytes.

It seems that when the length is not 0 bytes, there is no
need to explicitly delay the data stage since the transfer
is not completed until the user responds. However, when the
length is 0, there is no data stage and the transfer is
finished once setup() returns, hence there is a need to
explicitly delay completion.

This manifests as the following bugs:

Prior to 946ef68ad4e4 ('Let setup() return
USB_GADGET_DELAYED_STATUS'), when setup is 0 bytes, ffs
would require user to queue a 0 byte request in order to
clear setup state. However, that 0 byte request was actually
not needed and would hang and cause errors in other setup
requests.

After the above commit, 0 byte setups work since the gadget
now accepts empty queues to ep0 to clear the delay, but all
other setups hang.

Fixes: 946ef68ad4e4 ("Let setup() return USB_GADGET_DELAYED_STATUS")
Signed-off-by: Jerry Zhang <zhangjerry@google.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/gadget/function/f_fs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -3243,7 +3243,7 @@ static int ffs_func_setup(struct usb_fun
 	__ffs_event_add(ffs, FUNCTIONFS_SETUP);
 	spin_unlock_irqrestore(&ffs->ev.waitq.lock, flags);
 
-	return USB_GADGET_DELAYED_STATUS;
+	return creq->wLength == 0 ? USB_GADGET_DELAYED_STATUS : 0;
 }
 
 static bool ffs_func_req_match(struct usb_function *f,

[PATCH 4.9 24/33] driver core: Partially revert "driver core: correct devices shutdown order"

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

commit 722e5f2b1eec7de61117b7c0a7914761e3da2eda upstream.

Commit 52cdbdd49853 (driver core: correct device's shutdown order)
introduced a regression by breaking device shutdown on some systems.

Namely, the devices_kset_move_last() call in really_probe() added by
that commit is a mistake as it may cause parents to follow children
in the devices_kset list which then causes shutdown to fail.  For
example, if a device has children before really_probe() is called
for it (which is not uncommon), that call will cause it to be
reordered after the children in the devices_kset list and the
ordering of that list will not reflect the correct device shutdown
order any more.

Also it causes the devices_kset list to be constantly reordered
until all drivers have been probed which is totally pointless
overhead in the majority of cases and it only covered an issue
with system shutdown, while system-wide suspend/resume potentially
had the same issue on the affected platforms (which was not covered).

Moreover, the shutdown issue originally addressed by the change in
really_probe() made by commit 52cdbdd49853 is not present in 4.18-rc
any more, since dra7 started to use the sdhci-omap driver which
doesn't disable any regulators during shutdown, so the really_probe()
part of commit 52cdbdd49853 can be safely reverted.  [The original
issue was related to the omap_hsmmc driver used by dra7 previously.]

For the above reasons, revert the really_probe() modifications made
by commit 52cdbdd49853.

The other code changes made by commit 52cdbdd49853 are useful and
they need not be reverted.

Fixes: 52cdbdd49853 (driver core: correct device's shutdown order)
Link: https://lore.kernel.org/lkml/CAFgQCTt7VfqM=UyCnvNFxrSw8Z6cUtAi3HUwR4_xPAc03SgHjQ@mail.gmail.com/
Reported-by: Pingfan Liu <kernelfans@gmail.com>
Tested-by: Pingfan Liu <kernelfans@gmail.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/base/dd.c |    8 --------
 1 file changed, 8 deletions(-)

--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -363,14 +363,6 @@ re_probe:
 			goto probe_failed;
 	}
 
-	/*
-	 * Ensure devices are listed in devices_kset in correct order
-	 * It's important to move Dev to the end of devices_kset before
-	 * calling .probe, because it could be recursive and parent Dev
-	 * should always go first
-	 */
-	devices_kset_move_last(dev);
-
 	if (dev->bus->probe) {
 		ret = dev->bus->probe(dev);
 		if (ret)

[PATCH 4.9 25/33] can: xilinx_can: fix RX loop if RXNEMP is asserted without RXOK

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 32852c561bffd613d4ed7ec464b1e03e1b7b6c5c upstream.

If the device gets into a state where RXNEMP (RX FIFO not empty)
interrupt is asserted without RXOK (new frame received successfully)
interrupt being asserted, xcan_rx_poll() will continue to try to clear
RXNEMP without actually reading frames from RX FIFO. If the RX FIFO is
not empty, the interrupt will not be cleared and napi_schedule() will
just be called again.

This situation can occur when:

(a) xcan_rx() returns without reading RX FIFO due to an error condition.
The code tries to clear both RXOK and RXNEMP but RXNEMP will not clear
due to a frame still being in the FIFO. The frame will never be read
from the FIFO as RXOK is no longer set.

(b) A frame is received between xcan_rx_poll() reading interrupt status
and clearing RXOK. RXOK will be cleared, but RXNEMP will again remain
set as the new message is still in the FIFO.

I'm able to trigger case (b) by flooding the bus with frames under load.

There does not seem to be any benefit in using both RXNEMP and RXOK in
the way the driver does, and the polling example in the reference manual
(UG585 v1.10 18.3.7 Read Messages from RxFIFO) also says that either
RXOK or RXNEMP can be used for detecting incoming messages.

Fix the issue and simplify the RX processing by only using RXNEMP
without RXOK.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |   18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -101,7 +101,7 @@ enum xcan_reg {
 #define XCAN_INTR_ALL		(XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
 				 XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
 				 XCAN_IXR_RXNEMP_MASK | XCAN_IXR_ERROR_MASK | \
-				 XCAN_IXR_ARBLST_MASK | XCAN_IXR_RXOK_MASK)
+				 XCAN_IXR_ARBLST_MASK)
 
 /* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
 #define XCAN_BTR_SJW_SHIFT		7  /* Synchronous jump width */
@@ -709,15 +709,7 @@ static int xcan_rx_poll(struct napi_stru
 
 	isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
 	while ((isr & XCAN_IXR_RXNEMP_MASK) && (work_done < quota)) {
-		if (isr & XCAN_IXR_RXOK_MASK) {
-			priv->write_reg(priv, XCAN_ICR_OFFSET,
-				XCAN_IXR_RXOK_MASK);
-			work_done += xcan_rx(ndev);
-		} else {
-			priv->write_reg(priv, XCAN_ICR_OFFSET,
-				XCAN_IXR_RXNEMP_MASK);
-			break;
-		}
+		work_done += xcan_rx(ndev);
 		priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_RXNEMP_MASK);
 		isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
 	}
@@ -728,7 +720,7 @@ static int xcan_rx_poll(struct napi_stru
 	if (work_done < quota) {
 		napi_complete(napi);
 		ier = priv->read_reg(priv, XCAN_IER_OFFSET);
-		ier |= (XCAN_IXR_RXOK_MASK | XCAN_IXR_RXNEMP_MASK);
+		ier |= XCAN_IXR_RXNEMP_MASK;
 		priv->write_reg(priv, XCAN_IER_OFFSET, ier);
 	}
 	return work_done;
@@ -800,9 +792,9 @@ static irqreturn_t xcan_interrupt(int ir
 	}
 
 	/* Check for the type of receive interrupt and Processing it */
-	if (isr & (XCAN_IXR_RXNEMP_MASK | XCAN_IXR_RXOK_MASK)) {
+	if (isr & XCAN_IXR_RXNEMP_MASK) {
 		ier = priv->read_reg(priv, XCAN_IER_OFFSET);
-		ier &= ~(XCAN_IXR_RXNEMP_MASK | XCAN_IXR_RXOK_MASK);
+		ier &= ~XCAN_IXR_RXNEMP_MASK;
 		priv->write_reg(priv, XCAN_IER_OFFSET, ier);
 		napi_schedule(&priv->napi);
 	}

[PATCH 4.9 26/33] can: xilinx_can: fix power management handling

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 8ebd83bdb027f29870d96649dba18b91581ea829 upstream.

There are several issues with the suspend/resume handling code of the
driver:

- The device is attached and detached in the runtime_suspend() and
  runtime_resume() callbacks if the interface is running. However,
  during xcan_chip_start() the interface is considered running,
  causing the resume handler to incorrectly call netif_start_queue()
  at the beginning of xcan_chip_start(), and on xcan_chip_start() error
  return the suspend handler detaches the device leaving the user
  unable to bring-up the device anymore.

- The device is not brought properly up on system resume. A reset is
  done and the code tries to determine the bus state after that.
  However, after reset the device is always in Configuration mode
  (down), so the state checking code does not make sense and
  communication will also not work.

- The suspend callback tries to set the device to sleep mode (low-power
  mode which monitors the bus and brings the device back to normal mode
  on activity), but then immediately disables the clocks (possibly
  before the device reaches the sleep mode), which does not make sense
  to me. If a clean shutdown is wanted before disabling clocks, we can
  just bring it down completely instead of only sleep mode.

Reorganize the PM code so that only the clock logic remains in the
runtime PM callbacks and the system PM callbacks contain the device
bring-up/down logic. This makes calling the runtime PM callbacks during
e.g. xcan_chip_start() safe.

The system PM callbacks now simply call common code to start/stop the
HW if the interface was running, replacing the broken code from before.

xcan_chip_stop() is updated to use the common reset code so that it will
wait for the reset to complete. Reset also disables all interrupts so do
not do that separately.

Also, the device_may_wakeup() checks are removed as the driver does not
have wakeup support.

Tested on Zynq-7000 integrated CAN.

Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |   69 +++++++++++++++++--------------------------
 1 file changed, 28 insertions(+), 41 deletions(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -811,13 +811,9 @@ static irqreturn_t xcan_interrupt(int ir
 static void xcan_chip_stop(struct net_device *ndev)
 {
 	struct xcan_priv *priv = netdev_priv(ndev);
-	u32 ier;
 
 	/* Disable interrupts and leave the can in configuration mode */
-	ier = priv->read_reg(priv, XCAN_IER_OFFSET);
-	ier &= ~XCAN_INTR_ALL;
-	priv->write_reg(priv, XCAN_IER_OFFSET, ier);
-	priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
+	set_reset_mode(ndev);
 	priv->can.state = CAN_STATE_STOPPED;
 }
 
@@ -950,10 +946,15 @@ static const struct net_device_ops xcan_
  */
 static int __maybe_unused xcan_suspend(struct device *dev)
 {
-	if (!device_may_wakeup(dev))
-		return pm_runtime_force_suspend(dev);
+	struct net_device *ndev = dev_get_drvdata(dev);
 
-	return 0;
+	if (netif_running(ndev)) {
+		netif_stop_queue(ndev);
+		netif_device_detach(ndev);
+		xcan_chip_stop(ndev);
+	}
+
+	return pm_runtime_force_suspend(dev);
 }
 
 /**
@@ -965,11 +966,27 @@ static int __maybe_unused xcan_suspend(s
  */
 static int __maybe_unused xcan_resume(struct device *dev)
 {
-	if (!device_may_wakeup(dev))
-		return pm_runtime_force_resume(dev);
+	struct net_device *ndev = dev_get_drvdata(dev);
+	int ret;
 
-	return 0;
+	ret = pm_runtime_force_resume(dev);
+	if (ret) {
+		dev_err(dev, "pm_runtime_force_resume failed on resume\n");
+		return ret;
+	}
+
+	if (netif_running(ndev)) {
+		ret = xcan_chip_start(ndev);
+		if (ret) {
+			dev_err(dev, "xcan_chip_start failed on resume\n");
+			return ret;
+		}
+
+		netif_device_attach(ndev);
+		netif_start_queue(ndev);
+	}
 
+	return 0;
 }
 
 /**
@@ -984,14 +1001,6 @@ static int __maybe_unused xcan_runtime_s
 	struct net_device *ndev = dev_get_drvdata(dev);
 	struct xcan_priv *priv = netdev_priv(ndev);
 
-	if (netif_running(ndev)) {
-		netif_stop_queue(ndev);
-		netif_device_detach(ndev);
-	}
-
-	priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK);
-	priv->can.state = CAN_STATE_SLEEPING;
-
 	clk_disable_unprepare(priv->bus_clk);
 	clk_disable_unprepare(priv->can_clk);
 
@@ -1010,7 +1019,6 @@ static int __maybe_unused xcan_runtime_r
 	struct net_device *ndev = dev_get_drvdata(dev);
 	struct xcan_priv *priv = netdev_priv(ndev);
 	int ret;
-	u32 isr, status;
 
 	ret = clk_prepare_enable(priv->bus_clk);
 	if (ret) {
@@ -1024,27 +1032,6 @@ static int __maybe_unused xcan_runtime_r
 		return ret;
 	}
 
-	priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
-	isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
-	status = priv->read_reg(priv, XCAN_SR_OFFSET);
-
-	if (netif_running(ndev)) {
-		if (isr & XCAN_IXR_BSOFF_MASK) {
-			priv->can.state = CAN_STATE_BUS_OFF;
-			priv->write_reg(priv, XCAN_SRR_OFFSET,
-					XCAN_SRR_RESET_MASK);
-		} else if ((status & XCAN_SR_ESTAT_MASK) ==
-					XCAN_SR_ESTAT_MASK) {
-			priv->can.state = CAN_STATE_ERROR_PASSIVE;
-		} else if (status & XCAN_SR_ERRWRN_MASK) {
-			priv->can.state = CAN_STATE_ERROR_WARNING;
-		} else {
-			priv->can.state = CAN_STATE_ERROR_ACTIVE;
-		}
-		netif_device_attach(ndev);
-		netif_start_queue(ndev);
-	}
-
 	return 0;
 }
 

[PATCH 4.9 27/33] can: xilinx_can: fix recovery from error states not being propagated

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 877e0b75947e2c7acf5624331bb17ceb093c98ae upstream.

The xilinx_can driver contains no mechanism for propagating recovery
from CAN_STATE_ERROR_WARNING and CAN_STATE_ERROR_PASSIVE.

Add such a mechanism by factoring the handling of
XCAN_STATE_ERROR_PASSIVE and XCAN_STATE_ERROR_WARNING out of
xcan_err_interrupt and checking for recovery after RX and TX if the
interface is in one of those states.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |  155 +++++++++++++++++++++++++++++++++++--------
 1 file changed, 127 insertions(+), 28 deletions(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -2,6 +2,7 @@
  *
  * Copyright (C) 2012 - 2014 Xilinx, Inc.
  * Copyright (C) 2009 PetaLogix. All rights reserved.
+ * Copyright (C) 2017 Sandvik Mining and Construction Oy
  *
  * Description:
  * This driver is developed for Axi CAN IP and for Zynq CANPS Controller.
@@ -530,6 +531,123 @@ static int xcan_rx(struct net_device *nd
 }
 
 /**
+ * xcan_current_error_state - Get current error state from HW
+ * @ndev:	Pointer to net_device structure
+ *
+ * Checks the current CAN error state from the HW. Note that this
+ * only checks for ERROR_PASSIVE and ERROR_WARNING.
+ *
+ * Return:
+ * ERROR_PASSIVE or ERROR_WARNING if either is active, ERROR_ACTIVE
+ * otherwise.
+ */
+static enum can_state xcan_current_error_state(struct net_device *ndev)
+{
+	struct xcan_priv *priv = netdev_priv(ndev);
+	u32 status = priv->read_reg(priv, XCAN_SR_OFFSET);
+
+	if ((status & XCAN_SR_ESTAT_MASK) == XCAN_SR_ESTAT_MASK)
+		return CAN_STATE_ERROR_PASSIVE;
+	else if (status & XCAN_SR_ERRWRN_MASK)
+		return CAN_STATE_ERROR_WARNING;
+	else
+		return CAN_STATE_ERROR_ACTIVE;
+}
+
+/**
+ * xcan_set_error_state - Set new CAN error state
+ * @ndev:	Pointer to net_device structure
+ * @new_state:	The new CAN state to be set
+ * @cf:		Error frame to be populated or NULL
+ *
+ * Set new CAN error state for the device, updating statistics and
+ * populating the error frame if given.
+ */
+static void xcan_set_error_state(struct net_device *ndev,
+				 enum can_state new_state,
+				 struct can_frame *cf)
+{
+	struct xcan_priv *priv = netdev_priv(ndev);
+	u32 ecr = priv->read_reg(priv, XCAN_ECR_OFFSET);
+	u32 txerr = ecr & XCAN_ECR_TEC_MASK;
+	u32 rxerr = (ecr & XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT;
+
+	priv->can.state = new_state;
+
+	if (cf) {
+		cf->can_id |= CAN_ERR_CRTL;
+		cf->data[6] = txerr;
+		cf->data[7] = rxerr;
+	}
+
+	switch (new_state) {
+	case CAN_STATE_ERROR_PASSIVE:
+		priv->can.can_stats.error_passive++;
+		if (cf)
+			cf->data[1] = (rxerr > 127) ?
+					CAN_ERR_CRTL_RX_PASSIVE :
+					CAN_ERR_CRTL_TX_PASSIVE;
+		break;
+	case CAN_STATE_ERROR_WARNING:
+		priv->can.can_stats.error_warning++;
+		if (cf)
+			cf->data[1] |= (txerr > rxerr) ?
+					CAN_ERR_CRTL_TX_WARNING :
+					CAN_ERR_CRTL_RX_WARNING;
+		break;
+	case CAN_STATE_ERROR_ACTIVE:
+		if (cf)
+			cf->data[1] |= CAN_ERR_CRTL_ACTIVE;
+		break;
+	default:
+		/* non-ERROR states are handled elsewhere */
+		WARN_ON(1);
+		break;
+	}
+}
+
+/**
+ * xcan_update_error_state_after_rxtx - Update CAN error state after RX/TX
+ * @ndev:	Pointer to net_device structure
+ *
+ * If the device is in a ERROR-WARNING or ERROR-PASSIVE state, check if
+ * the performed RX/TX has caused it to drop to a lesser state and set
+ * the interface state accordingly.
+ */
+static void xcan_update_error_state_after_rxtx(struct net_device *ndev)
+{
+	struct xcan_priv *priv = netdev_priv(ndev);
+	enum can_state old_state = priv->can.state;
+	enum can_state new_state;
+
+	/* changing error state due to successful frame RX/TX can only
+	 * occur from these states
+	 */
+	if (old_state != CAN_STATE_ERROR_WARNING &&
+	    old_state != CAN_STATE_ERROR_PASSIVE)
+		return;
+
+	new_state = xcan_current_error_state(ndev);
+
+	if (new_state != old_state) {
+		struct sk_buff *skb;
+		struct can_frame *cf;
+
+		skb = alloc_can_err_skb(ndev, &cf);
+
+		xcan_set_error_state(ndev, new_state, skb ? cf : NULL);
+
+		if (skb) {
+			struct net_device_stats *stats = &ndev->stats;
+
+			stats->rx_packets++;
+			stats->rx_bytes += cf->can_dlc;
+			netif_rx(skb);
+		}
+	}
+}
+
+/**
  * xcan_err_interrupt - error frame Isr
  * @ndev:	net_device pointer
  * @isr:	interrupt status register value
@@ -544,16 +662,12 @@ static void xcan_err_interrupt(struct ne
 	struct net_device_stats *stats = &ndev->stats;
 	struct can_frame *cf;
 	struct sk_buff *skb;
-	u32 err_status, status, txerr = 0, rxerr = 0;
+	u32 err_status;
 
 	skb = alloc_can_err_skb(ndev, &cf);
 
 	err_status = priv->read_reg(priv, XCAN_ESR_OFFSET);
 	priv->write_reg(priv, XCAN_ESR_OFFSET, err_status);
-	txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
-	rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
-			XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);
-	status = priv->read_reg(priv, XCAN_SR_OFFSET);
 
 	if (isr & XCAN_IXR_BSOFF_MASK) {
 		priv->can.state = CAN_STATE_BUS_OFF;
@@ -563,28 +677,10 @@ static void xcan_err_interrupt(struct ne
 		can_bus_off(ndev);
 		if (skb)
 			cf->can_id |= CAN_ERR_BUSOFF;
-	} else if ((status & XCAN_SR_ESTAT_MASK) == XCAN_SR_ESTAT_MASK) {
-		priv->can.state = CAN_STATE_ERROR_PASSIVE;
-		priv->can.can_stats.error_passive++;
-		if (skb) {
-			cf->can_id |= CAN_ERR_CRTL;
-			cf->data[1] = (rxerr > 127) ?
-					CAN_ERR_CRTL_RX_PASSIVE :
-					CAN_ERR_CRTL_TX_PASSIVE;
-			cf->data[6] = txerr;
-			cf->data[7] = rxerr;
-		}
-	} else if (status & XCAN_SR_ERRWRN_MASK) {
-		priv->can.state = CAN_STATE_ERROR_WARNING;
-		priv->can.can_stats.error_warning++;
-		if (skb) {
-			cf->can_id |= CAN_ERR_CRTL;
-			cf->data[1] |= (txerr > rxerr) ?
-					CAN_ERR_CRTL_TX_WARNING :
-					CAN_ERR_CRTL_RX_WARNING;
-			cf->data[6] = txerr;
-			cf->data[7] = rxerr;
-		}
+	} else {
+		enum can_state new_state = xcan_current_error_state(ndev);
+
+		xcan_set_error_state(ndev, new_state, skb ? cf : NULL);
 	}
 
 	/* Check for Arbitration lost interrupt */
@@ -714,8 +810,10 @@ static int xcan_rx_poll(struct napi_stru
 		isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
 	}
 
-	if (work_done)
+	if (work_done) {
 		can_led_event(ndev, CAN_LED_EVENT_RX);
+		xcan_update_error_state_after_rxtx(ndev);
+	}
 
 	if (work_done < quota) {
 		napi_complete(napi);
@@ -746,6 +844,7 @@ static void xcan_tx_interrupt(struct net
 		isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
 	}
 	can_led_event(ndev, CAN_LED_EVENT_TX);
+	xcan_update_error_state_after_rxtx(ndev);
 	netif_wake_queue(ndev);
 }
 

[PATCH 4.9 28/33] can: xilinx_can: fix device dropping off bus on RX overrun

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 2574fe54515ed3487405de329e4e9f13d7098c10 upstream.

The xilinx_can driver performs a software reset when an RX overrun is
detected. This causes the device to enter Configuration mode where no
messages are received or transmitted.

The documentation does not mention any need to perform a reset on an RX
overrun, and testing by inducing an RX overflow also indicated that the
device continues to work just fine without a reset.

Remove the software reset.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |    1 -
 1 file changed, 1 deletion(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -696,7 +696,6 @@ static void xcan_err_interrupt(struct ne
 	if (isr & XCAN_IXR_RXOFLW_MASK) {
 		stats->rx_over_errors++;
 		stats->rx_errors++;
-		priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
 		if (skb) {
 			cf->can_id |= CAN_ERR_CRTL;
 			cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;

[PATCH 4.9 29/33] can: xilinx_can: keep only 1-2 frames in TX FIFO to fix TX accounting

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 620050d9c2be15c47017ba95efe59e0832e99a56 upstream.

The xilinx_can driver assumes that the TXOK interrupt only clears after
it has been acknowledged as many times as there have been successfully
sent frames.

However, the documentation does not mention such behavior, instead
saying just that the interrupt is cleared when the clear bit is set.

Similarly, testing seems to also suggest that it is immediately cleared
regardless of the amount of frames having been sent. Performing some
heavy TX load and then going back to idle has the tx_head drifting
further away from tx_tail over time, steadily reducing the amount of
frames the driver keeps in the TX FIFO (but not to zero, as the TXOK
interrupt always frees up space for 1 frame from the driver's
perspective, so frames continue to be sent) and delaying the local echo
frames.

The TX FIFO tracking is also otherwise buggy as it does not account for
TX FIFO being cleared after software resets, causing
  BUG!, TX FIFO full when queue awake!
messages to be output.

There does not seem to be any way to accurately track the state of the
TX FIFO for local echo support while using the full TX FIFO.

The Zynq version of the HW (but not the soft-AXI version) has watermark
programming support and with it an additional TX-FIFO-empty interrupt
bit.

Modify the driver to only put 1 frame into TX FIFO at a time on soft-AXI
and 2 frames at a time on Zynq. On Zynq the TXFEMP interrupt bit is used
to detect whether 1 or 2 frames have been sent at interrupt processing
time.

Tested with the integrated CAN on Zynq-7000 SoC. The 1-frame-FIFO mode
was also tested.

An alternative way to solve this would be to drop local echo support but
keep using the full TX FIFO.

v2: Add FIFO space check before TX queue wake with locking to
synchronize with queue stop. This avoids waking the queue when xmit()
had just filled it.

v3: Keep local echo support and reduce the amount of frames in FIFO
instead as suggested by Marc Kleine-Budde.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |  139 ++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 123 insertions(+), 16 deletions(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -26,8 +26,10 @@
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/skbuff.h>
+#include <linux/spinlock.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/can/dev.h>
@@ -119,6 +121,7 @@ enum xcan_reg {
 /**
  * struct xcan_priv - This definition define CAN driver instance
  * @can:			CAN private data structure.
+ * @tx_lock:			Lock for synchronizing TX interrupt handling
  * @tx_head:			Tx CAN packets ready to send on the queue
  * @tx_tail:			Tx CAN packets successfully sended on the queue
  * @tx_max:			Maximum number packets the driver can send
@@ -133,6 +136,7 @@ enum xcan_reg {
  */
 struct xcan_priv {
 	struct can_priv can;
+	spinlock_t tx_lock;
 	unsigned int tx_head;
 	unsigned int tx_tail;
 	unsigned int tx_max;
@@ -160,6 +164,11 @@ static const struct can_bittiming_const
 	.brp_inc = 1,
 };
 
+#define XCAN_CAP_WATERMARK	0x0001
+struct xcan_devtype_data {
+	unsigned int caps;
+};
+
 /**
  * xcan_write_reg_le - Write a value to the device register little endian
  * @priv:	Driver private data structure
@@ -239,6 +248,10 @@ static int set_reset_mode(struct net_dev
 		usleep_range(500, 10000);
 	}
 
+	/* reset clears FIFOs */
+	priv->tx_head = 0;
+	priv->tx_tail = 0;
+
 	return 0;
 }
 
@@ -393,6 +406,7 @@ static int xcan_start_xmit(struct sk_buf
 	struct net_device_stats *stats = &ndev->stats;
 	struct can_frame *cf = (struct can_frame *)skb->data;
 	u32 id, dlc, data[2] = {0, 0};
+	unsigned long flags;
 
 	if (can_dropped_invalid_skb(ndev, skb))
 		return NETDEV_TX_OK;
@@ -440,6 +454,9 @@ static int xcan_start_xmit(struct sk_buf
 		data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
 
 	can_put_echo_skb(skb, ndev, priv->tx_head % priv->tx_max);
+
+	spin_lock_irqsave(&priv->tx_lock, flags);
+
 	priv->tx_head++;
 
 	/* Write the Frame to Xilinx CAN TX FIFO */
@@ -455,10 +472,16 @@ static int xcan_start_xmit(struct sk_buf
 		stats->tx_bytes += cf->can_dlc;
 	}
 
+	/* Clear TX-FIFO-empty interrupt for xcan_tx_interrupt() */
+	if (priv->tx_max > 1)
+		priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXFEMP_MASK);
+
 	/* Check if the TX buffer is full */
 	if ((priv->tx_head - priv->tx_tail) == priv->tx_max)
 		netif_stop_queue(ndev);
 
+	spin_unlock_irqrestore(&priv->tx_lock, flags);
+
 	return NETDEV_TX_OK;
 }
 
@@ -832,19 +855,71 @@ static void xcan_tx_interrupt(struct net
 {
 	struct xcan_priv *priv = netdev_priv(ndev);
 	struct net_device_stats *stats = &ndev->stats;
+	unsigned int frames_in_fifo;
+	int frames_sent = 1; /* TXOK => at least 1 frame was sent */
+	unsigned long flags;
+	int retries = 0;
+
+	/* Synchronize with xmit as we need to know the exact number
+	 * of frames in the FIFO to stay in sync due to the TXFEMP
+	 * handling.
+	 * This also prevents a race between netif_wake_queue() and
+	 * netif_stop_queue().
+	 */
+	spin_lock_irqsave(&priv->tx_lock, flags);
+
+	frames_in_fifo = priv->tx_head - priv->tx_tail;
+
+	if (WARN_ON_ONCE(frames_in_fifo == 0)) {
+		/* clear TXOK anyway to avoid getting back here */
+		priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXOK_MASK);
+		spin_unlock_irqrestore(&priv->tx_lock, flags);
+		return;
+	}
+
+	/* Check if 2 frames were sent (TXOK only means that at least 1
+	 * frame was sent).
+	 */
+	if (frames_in_fifo > 1) {
+		WARN_ON(frames_in_fifo > priv->tx_max);
+
+		/* Synchronize TXOK and isr so that after the loop:
+		 * (1) isr variable is up-to-date at least up to TXOK clear
+		 *     time. This avoids us clearing a TXOK of a second frame
+		 *     but not noticing that the FIFO is now empty and thus
+		 *     marking only a single frame as sent.
+		 * (2) No TXOK is left. Having one could mean leaving a
+		 *     stray TXOK as we might process the associated frame
+		 *     via TXFEMP handling as we read TXFEMP *after* TXOK
+		 *     clear to satisfy (1).
+		 */
+		while ((isr & XCAN_IXR_TXOK_MASK) && !WARN_ON(++retries == 100)) {
+			priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXOK_MASK);
+			isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
+		}
 
-	while ((priv->tx_head - priv->tx_tail > 0) &&
-			(isr & XCAN_IXR_TXOK_MASK)) {
+		if (isr & XCAN_IXR_TXFEMP_MASK) {
+			/* nothing in FIFO anymore */
+			frames_sent = frames_in_fifo;
+		}
+	} else {
+		/* single frame in fifo, just clear TXOK */
 		priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXOK_MASK);
+	}
+
+	while (frames_sent--) {
 		can_get_echo_skb(ndev, priv->tx_tail %
 					priv->tx_max);
 		priv->tx_tail++;
 		stats->tx_packets++;
-		isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
 	}
+
+	netif_wake_queue(ndev);
+
+	spin_unlock_irqrestore(&priv->tx_lock, flags);
+
 	can_led_event(ndev, CAN_LED_EVENT_TX);
 	xcan_update_error_state_after_rxtx(ndev);
-	netif_wake_queue(ndev);
 }
 
 /**
@@ -1138,6 +1213,18 @@ static const struct dev_pm_ops xcan_dev_
 	SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL)
 };
 
+static const struct xcan_devtype_data xcan_zynq_data = {
+	.caps = XCAN_CAP_WATERMARK,
+};
+
+/* Match table for OF platform binding */
+static const struct of_device_id xcan_of_match[] = {
+	{ .compatible = "xlnx,zynq-can-1.0", .data = &xcan_zynq_data },
+	{ .compatible = "xlnx,axi-can-1.00.a", },
+	{ /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, xcan_of_match);
+
 /**
  * xcan_probe - Platform registration call
  * @pdev:	Handle to the platform device structure
@@ -1152,8 +1239,10 @@ static int xcan_probe(struct platform_de
 	struct resource *res; /* IO mem resources */
 	struct net_device *ndev;
 	struct xcan_priv *priv;
+	const struct of_device_id *of_id;
+	int caps = 0;
 	void __iomem *addr;
-	int ret, rx_max, tx_max;
+	int ret, rx_max, tx_max, tx_fifo_depth;
 
 	/* Get the virtual base address for the device */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1163,7 +1252,8 @@ static int xcan_probe(struct platform_de
 		goto err;
 	}
 
-	ret = of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth", &tx_max);
+	ret = of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth",
+				   &tx_fifo_depth);
 	if (ret < 0)
 		goto err;
 
@@ -1171,6 +1261,30 @@ static int xcan_probe(struct platform_de
 	if (ret < 0)
 		goto err;
 
+	of_id = of_match_device(xcan_of_match, &pdev->dev);
+	if (of_id) {
+		const struct xcan_devtype_data *devtype_data = of_id->data;
+
+		if (devtype_data)
+			caps = devtype_data->caps;
+	}
+
+	/* There is no way to directly figure out how many frames have been
+	 * sent when the TXOK interrupt is processed. If watermark programming
+	 * is supported, we can have 2 frames in the FIFO and use TXFEMP
+	 * to determine if 1 or 2 frames have been sent.
+	 * Theoretically we should be able to use TXFWMEMP to determine up
+	 * to 3 frames, but it seems that after putting a second frame in the
+	 * FIFO, with watermark at 2 frames, it can happen that TXFWMEMP (less
+	 * than 2 frames in FIFO) is set anyway with no TXOK (a frame was
+	 * sent), which is not a sensible state - possibly TXFWMEMP is not
+	 * completely synchronized with the rest of the bits?
+	 */
+	if (caps & XCAN_CAP_WATERMARK)
+		tx_max = min(tx_fifo_depth, 2);
+	else
+		tx_max = 1;
+
 	/* Create a CAN device instance */
 	ndev = alloc_candev(sizeof(struct xcan_priv), tx_max);
 	if (!ndev)
@@ -1185,6 +1299,7 @@ static int xcan_probe(struct platform_de
 					CAN_CTRLMODE_BERR_REPORTING;
 	priv->reg_base = addr;
 	priv->tx_max = tx_max;
+	spin_lock_init(&priv->tx_lock);
 
 	/* Get IRQ for the device */
 	ndev->irq = platform_get_irq(pdev, 0);
@@ -1249,9 +1364,9 @@ static int xcan_probe(struct platform_de
 
 	pm_runtime_put(&pdev->dev);
 
-	netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth:%d\n",
+	netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth: actual %d, using %d\n",
 			priv->reg_base, ndev->irq, priv->can.clock.freq,
-			priv->tx_max);
+			tx_fifo_depth, priv->tx_max);
 
 	return 0;
 
@@ -1285,14 +1400,6 @@ static int xcan_remove(struct platform_d
 	return 0;
 }
 
-/* Match table for OF platform binding */
-static const struct of_device_id xcan_of_match[] = {
-	{ .compatible = "xlnx,zynq-can-1.0", },
-	{ .compatible = "xlnx,axi-can-1.00.a", },
-	{ /* end of list */ },
-};
-MODULE_DEVICE_TABLE(of, xcan_of_match);
-
 static struct platform_driver xcan_driver = {
 	.probe = xcan_probe,
 	.remove	= xcan_remove,

[PATCH 4.9 30/33] can: xilinx_can: fix incorrect clear of non-processed interrupts

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 2f4f0f338cf453bfcdbcf089e177c16f35f023c8 upstream.

xcan_interrupt() clears ERROR|RXOFLV|BSOFF|ARBLST interrupts if any of
them is asserted. This does not take into account that some of them
could have been asserted between interrupt status read and interrupt
clear, therefore clearing them without handling them.

Fix the code to only clear those interrupts that it knows are asserted
and therefore going to be processed in xcan_err_interrupt().

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -938,6 +938,7 @@ static irqreturn_t xcan_interrupt(int ir
 	struct net_device *ndev = (struct net_device *)dev_id;
 	struct xcan_priv *priv = netdev_priv(ndev);
 	u32 isr, ier;
+	u32 isr_errors;
 
 	/* Get the interrupt status from Xilinx CAN */
 	isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
@@ -956,11 +957,10 @@ static irqreturn_t xcan_interrupt(int ir
 		xcan_tx_interrupt(ndev, isr);
 
 	/* Check for the type of error interrupt and Processing it */
-	if (isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
-			XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK)) {
-		priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_ERROR_MASK |
-				XCAN_IXR_RXOFLW_MASK | XCAN_IXR_BSOFF_MASK |
-				XCAN_IXR_ARBLST_MASK));
+	isr_errors = isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
+			    XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK);
+	if (isr_errors) {
+		priv->write_reg(priv, XCAN_ICR_OFFSET, isr_errors);
 		xcan_err_interrupt(ndev, isr);
 	}
 

[PATCH 4.9 31/33] can: xilinx_can: fix RX overflow interrupt not being enabled

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Anssi Hannula <anssi.hannula@bitwise.fi>

commit 83997997252f5d3fc7f04abc24a89600c2b504ab upstream.

RX overflow interrupt (RXOFLW) is disabled even though xcan_interrupt()
processes it. This means that an RX overflow interrupt will only be
processed when another interrupt gets asserted (e.g. for RX/TX).

Fix that by enabling the RXOFLW interrupt.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula <anssi.hannula@bitwise.fi>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/can/xilinx_can.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/can/xilinx_can.c
+++ b/drivers/net/can/xilinx_can.c
@@ -104,7 +104,7 @@ enum xcan_reg {
 #define XCAN_INTR_ALL		(XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
 				 XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
 				 XCAN_IXR_RXNEMP_MASK | XCAN_IXR_ERROR_MASK | \
-				 XCAN_IXR_ARBLST_MASK)
+				 XCAN_IXR_RXOFLW_MASK | XCAN_IXR_ARBLST_MASK)
 
 /* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
 #define XCAN_BTR_SJW_SHIFT		7  /* Synchronous jump width */

[PATCH 4.9 32/33] turn off -Wattribute-alias

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arnd Bergmann <arnd@arndb.de>

Starting with gcc-8.1, we get a warning about all system call definitions,
which use an alias between functions with incompatible prototypes, e.g.:

In file included from ../mm/process_vm_access.c:19:
../include/linux/syscalls.h:211:18: warning: 'sys_process_vm_readv' alias between functions of incompatible types 'long int(pid_t,  const struct iovec *, long unsigned int,  const struct iovec *, long unsigned int,  long unsigned int)' {aka 'long int(int,  const struct iovec *, long unsigned int,  const struct iovec *, long unsigned int,  long unsigned int)'} and 'long int(long int,  long int,  long int,  long int,  long int,  long int)' [-Wattribute-alias]
  asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
                  ^~~
../include/linux/syscalls.h:207:2: note: in expansion of macro '__SYSCALL_DEFINEx'
  __SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
  ^~~~~~~~~~~~~~~~~
../include/linux/syscalls.h:201:36: note: in expansion of macro 'SYSCALL_DEFINEx'
 #define SYSCALL_DEFINE6(name, ...) SYSCALL_DEFINEx(6, _##name, __VA_ARGS__)
                                    ^~~~~~~~~~~~~~~
../mm/process_vm_access.c:300:1: note: in expansion of macro 'SYSCALL_DEFINE6'
 SYSCALL_DEFINE6(process_vm_readv, pid_t, pid, const struct iovec __user *, lvec,
 ^~~~~~~~~~~~~~~
../include/linux/syscalls.h:215:18: note: aliased declaration here
  asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
                  ^~~
../include/linux/syscalls.h:207:2: note: in expansion of macro '__SYSCALL_DEFINEx'
  __SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
  ^~~~~~~~~~~~~~~~~
../include/linux/syscalls.h:201:36: note: in expansion of macro 'SYSCALL_DEFINEx'
 #define SYSCALL_DEFINE6(name, ...) SYSCALL_DEFINEx(6, _##name, __VA_ARGS__)
                                    ^~~~~~~~~~~~~~~
../mm/process_vm_access.c:300:1: note: in expansion of macro 'SYSCALL_DEFINE6'
 SYSCALL_DEFINE6(process_vm_readv, pid_t, pid, const struct iovec __user *, lvec,

This is really noisy and does not indicate a real problem. In the latest
mainline kernel, this was addressed by commit bee20031772a ("disable
-Wattribute-alias warning for SYSCALL_DEFINEx()"), which seems too invasive
to backport.

This takes a much simpler approach and just disables the warning across the
kernel.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 Makefile |    1 +
 1 file changed, 1 insertion(+)

--- a/Makefile
+++ b/Makefile
@@ -635,6 +635,7 @@ KBUILD_CFLAGS	+= $(call cc-disable-warni
 KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
 KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
 KBUILD_CFLAGS	+= $(call cc-disable-warning, int-in-bool-context)
+KBUILD_CFLAGS	+= $(call cc-disable-warning, attribute-alias)
 
 ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
 KBUILD_CFLAGS	+= $(call cc-option,-ffunction-sections,)

[PATCH 4.9 33/33] exec: avoid gcc-8 warning for get_task_comm

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Arnd Bergmann <arnd@arndb.de>

commit 3756f6401c302617c5e091081ca4d26ab604bec5 upstream.

gcc-8 warns about using strncpy() with the source size as the limit:

  fs/exec.c:1223:32: error: argument to 'sizeof' in 'strncpy' call is the same expression as the source; did you mean to use the size of the destination? [-Werror=sizeof-pointer-memaccess]

This is indeed slightly suspicious, as it protects us from source
arguments without NUL-termination, but does not guarantee that the
destination is terminated.

This keeps the strncpy() to ensure we have properly padded target
buffer, but ensures that we use the correct length, by passing the
actual length of the destination buffer as well as adding a build-time
check to ensure it is exactly TASK_COMM_LEN.

There are only 23 callsites which I all reviewed to ensure this is
currently the case.  We could get away with doing only the check or
passing the right length, but it doesn't hurt to do both.

Link: http://lkml.kernel.org/r/20171205151724.1764896-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Aleksa Sarai <asarai@suse.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/exec.c             |    7 +++----
 include/linux/sched.h |    6 +++++-
 2 files changed, 8 insertions(+), 5 deletions(-)

--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1228,15 +1228,14 @@ killed:
 	return -EAGAIN;
 }
 
-char *get_task_comm(char *buf, struct task_struct *tsk)
+char *__get_task_comm(char *buf, size_t buf_size, struct task_struct *tsk)
 {
-	/* buf must be at least sizeof(tsk->comm) in size */
 	task_lock(tsk);
-	strncpy(buf, tsk->comm, sizeof(tsk->comm));
+	strncpy(buf, tsk->comm, buf_size);
 	task_unlock(tsk);
 	return buf;
 }
-EXPORT_SYMBOL_GPL(get_task_comm);
+EXPORT_SYMBOL_GPL(__get_task_comm);
 
 /*
  * These functions flushes out all traces of the currently running executable
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2999,7 +2999,11 @@ static inline void set_task_comm(struct
 {
 	__set_task_comm(tsk, from, false);
 }
-extern char *get_task_comm(char *to, struct task_struct *tsk);
+extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
+#define get_task_comm(buf, tsk) ({			\
+	BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN);	\
+	__get_task_comm(buf, sizeof(buf), tsk);		\
+})
 
 #ifdef CONFIG_SMP
 void scheduler_ipi(void);

Re: [PATCH 4.9 00/33] 4.9.116-stable review

[Nathan Chancellor]

On Fri, Jul 27, 2018 at 12:08:41PM +0200, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.116 release.
> There are 33 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Sun Jul 29 10:08:17 UTC 2018.
> Anything received after that time might be too late.
> 
> The whole patch series can be found in one patch at:
> 	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.116-rc1.gz
> or in the git tree and branch at:
> 	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
> 
> thanks,
> 
> greg k-h
> 

Merged, compiled with -Werror, and installed onto my OnePlus 6.

No initial issues noticed in dmesg or general usage.

Thanks!
Nathan

Re: [PATCH 4.9 00/33] 4.9.116-stable review

[Guenter Roeck]

On Fri, Jul 27, 2018 at 12:08:41PM +0200, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.116 release.
> There are 33 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Sun Jul 29 10:08:17 UTC 2018.
> Anything received after that time might be too late.
> 

Build results:
	total: 148 pass: 148 fail: 0
Qemu test results:
	total: 166 pass: 166 fail: 0

Details are available at http://kerneltests.org/builders/.

Guenter

Re: [PATCH 4.9 00/33] 4.9.116-stable review

[Shuah Khan]

On 07/27/2018 04:08 AM, Greg Kroah-Hartman wrote:
> This is the start of the stable review cycle for the 4.9.116 release.
> There are 33 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
> 
> Responses should be made by Sun Jul 29 10:08:17 UTC 2018.
> Anything received after that time might be too late.
> 
> The whole patch series can be found in one patch at:
> 	https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.116-rc1.gz
> or in the git tree and branch at:
> 	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
> 
> thanks,
> 
> greg k-h
> 

Compiled and booted on my test system. No dmesg regressions.

thanks,
-- Shuah

Re: [PATCH 4.9 00/33] 4.9.116-stable review

[Naresh Kamboju]

On 27 July 2018 at 15:38, Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
> This is the start of the stable review cycle for the 4.9.116 release.
> There are 33 patches in this series, all will be posted as a response
> to this one.  If anyone has any issues with these being applied, please
> let me know.
>
> Responses should be made by Sun Jul 29 10:08:17 UTC 2018.
> Anything received after that time might be too late.
>
> The whole patch series can be found in one patch at:
>         https://www.kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.9.116-rc1.gz
> or in the git tree and branch at:
>         git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.9.y
> and the diffstat can be found below.
>
> thanks,
>
> greg k-h

Results from Linaro’s test farm.
No regressions on arm64, arm and x86_64.

Summary
------------------------------------------------------------------------

kernel: 4.9.116-rc1
git repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
git branch: linux-4.9.y
git commit: 91355182b00639864b0312b2406735b3c0d9d879
git describe: v4.9.115-34-g91355182b006
Test details: https://qa-reports.linaro.org/lkft/linux-stable-rc-4.9-oe/build/v4.9.115-34-g91355182b006

No regressions (compared to build v4.9.115)


Ran 16484 total tests in the following environments and test suites.

Environments
--------------
- dragonboard-410c - arm64
- hi6220-hikey - arm64
- juno-r2 - arm64
- qemu_arm
- qemu_arm64
- qemu_x86_64
- x15 - arm
- x86_64

Test Suites
-----------
* boot
* kselftest
* libhugetlbfs
* ltp-cap_bounds-tests
* ltp-containers-tests
* ltp-cve-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-math-tests
* ltp-nptl-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* ltp-syscalls-tests
* ltp-timers-tests
* ltp-open-posix-tests
* kselftest-vsyscall-mode-native
* kselftest-vsyscall-mode-none

-- 
Linaro LKFT
https://lkft.linaro.org