Since control vNICs don't have a netdev, they can't use napi and
queuing stack provides.  Add simple tasklet-based data receive
and send of control messages with queuing on a skb_list.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Out of the three stages of ifup/ifdown (allocate, configure, start)
- this commit prepares the configuration stage for working with
control vNICs.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vNICs used for sending and receiving control messages shouldn't
really have a netdev.  Add the ability to initialize vNICs for
netdev-less operation.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We want to be able to inspect the state of descriptor rings of
the control vNIC, so it will use the same interface as data vNICs.

Make sure the code doesn't use netdevs to determine state
of the rings and names things appropriately.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

To be able to reuse print macros easily with control vNICs make the
macros check if netdev pointer is populated and use dev_* print
functions otherwise.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move nfp_net_vecs_init() after all datapath functions.  We will need
to init poll() callbacks from this function soon.

No functional changes.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On the close path reuse the ring free helpers introduced for runtime
reconfiguration.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Our open/close implementations have 3 stages:
 - allocation/freeing of ring resources, irqs etc.,
 - device config,
 - device/stack enable (can't fail).

Right now all of those stages are placed in separate functions,
apart from allocation during open.  Fix that.  It will make it
easier for us to allocate resources for netdev-less vNICs.
Because we want to reuse allocation code in netdev-less vNICs
leave the netif_set_real_num_[rt]x_queues() calls inside open.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We will soon reuse parts of .ndo_stop() for clean up after errors
in .ndo_open().  Reorder the associated functions to make that possible.

No functional changes.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Both the IMX51 and IMX53 datasheet indicates that the MIB counters
should be cleared during setup. Otherwise random numbers are returned
via ethtool -S.  Add a quirk and a function to do this.

Tested on an IMX51.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Just some simple overlapping changes in marvell PHY driver
and the DSA core code.
Signed-off-by: David S. Miller <davem@davemloft.net>

Russell King says:

====================
net: Add phylib support for MV88X3310 10G phy

This patch series adds support for the Marvell 88x3310 PHY found on
the SolidRun Macchiatobin board.

The first patch introduces a set of generic Clause 45 PHY helpers that
C45 PHY drivers can make use of if they wish.

Patch 2 ensures that the Clause 22 aneg_done function will not be
called for incompatible Clause 45 PHYs.

Patch 3 fixes the aneg restart to be compatible with C45 PHYs - it can
currently only cope with C22 PHYs.

Patch 4 moves the "gen10g" driver into the Clause 45 code, grouping all
core clause 45 code together.

Patch 5 adds the phy_interface_t types for XAUI and 10GBase-KR links.
As 10GBase-KR appears to be compatible with XFI and SFI, XFI and SFI,
I currently see no reason to add XFI and SFI interface modes.  There
seems to be vendor code out there using these, but they all alias back
to the same hardware settings.

Patch 6 adds support for the MV88X3310 PHY, which supports both the
copper and fiber interfaces.  It should be noted that the MV88X3310
automatically switches its MAC facing interface between 10GBase-KR
and SGMII depending on the negotiated speed.  This was discussed with
Florian, and we agreed to update the phy interface mode depending on
the properties of the actual link mode to the PHY.

v2:
- update sysfs-class-net-phydev documentation
- avoid genphy_aneg_done for non-C22 PHYs
- expand comment about 0x30 constant
- add comment about lack of reset
- configure driver using MARVELL_10G_PHY
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add phylib support for the Marvell Alaska X 10 Gigabit PHY (MV88X3310).
This phy is able to operate at 10G, 1G, 100M and 10M speeds, and only
supports Clause 45 accesses.

The PHY appears (based on the vendor IDs) to be two different vendors
IP, with each devad containing several instances.

This PHY driver has only been tested with the RJ45 copper port, fiber
port and a Marvell Armada 8040-based ethernet interface.

It should be noted that to use the full range of speeds, MAC drivers
need to also reconfigure the link mode as per phydev->interface, since
the PHY automatically changes its interface mode depending on the
negotiated speed.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

XAUI allows XGMII to reach an extended distance by using a XGXS layer at
each end of the MAC to PHY link, operating over four Serdes lanes.

10GBASE-KR is a single lane Serdes backplane ethernet connection method
with autonegotiation on the link.  Some PHYs use this to connect to the
ethernet interface at 10G speeds, switching to other connection types
when utilising slower speeds.

10GBASE-KR is also used for XFI and SFI to connect to XFP and SFP fiber
modules.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move the old 10G genphy support to sit beside the new clause 45 library
functions, so all the 10G phy code is together.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

genphy_restart_aneg() can only restart autonegotiation on clause 22
PHYs.  Add a phy_restart_aneg() function which selects between the
clause 22 and clause 45 restart functionality depending on the PHY
type and whether the Clause 45 PHY supports the Clause 22 register set.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Avoid calling genphy_aneg_done() for PHYs that do not implement the
Clause 22 register set.

Clause 45 PHYs may implement the Clause 22 register set along with the
Clause 22 extension MMD.  Hence, we can't simply block access to the
Clause 22 functions based on the PHY being a Clause 45 PHY.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Add generic helpers for 802.3 clause 45 PHYs for >= 10Gbps support.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:

 1) Made TCP congestion control documentation match current reality,
    from Anmol Sarma.

 2) Various build warning and failure fixes from Arnd Bergmann.

 3) Fix SKB list leak in ipv6_gso_segment().

 4) Use after free in ravb driver, from Eugeniu Rosca.

 5) Don't use udp_poll() in ping protocol driver, from Eric Dumazet.

 6) Don't crash in PCI error recovery of cxgb4 driver, from Guilherme
    Piccoli.

 7) _SRC_NAT_DONE_BIT needs to be cleared using atomics, from Liping
    Zhang.

 8) Use after free in vxlan deletion, from Mark Bloch.

 9) Fix ordering of NAPI poll enabled in ethoc driver, from Max
    Filippov.

10) Fix stmmac hangs with TSO, from Niklas Cassel.

11) Fix crash in CALIPSO ipv6, from Richard Haines.

12) Clear nh_flags properly on mpls link up. From Roopa Prabhu.

13) Fix regression in sk_err socket error queue handling, noticed by
    ping applications. From Soheil Hassas Yeganeh.

14) Update mlx4/mlx5 MAINTAINERS information.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (78 commits)
  net: stmmac: fix a broken u32 less than zero check
  net: stmmac: fix completely hung TX when using TSO
  net: ethoc: enable NAPI before poll may be scheduled
  net: bridge: fix a null pointer dereference in br_afspec
  ravb: Fix use-after-free on `ifconfig eth0 down`
  net/ipv6: Fix CALIPSO causing GPF with datagram support
  net: stmmac: ensure jumbo_frm error return is correctly checked for -ve value
  Revert "sit: reload iphdr in ipip6_rcv"
  i40e/i40evf: proper update of the page_offset field
  i40e: Fix state flags for bit set and clean operations of PF
  iwlwifi: fix host command memory leaks
  iwlwifi: fix min API version for 7265D, 3168, 8000 and 8265
  iwlwifi: mvm: clear new beacon command template struct
  iwlwifi: mvm: don't fail when removing a key from an inexisting sta
  iwlwifi: pcie: only use d0i3 in suspend/resume if system_pm is set to d0i3
  iwlwifi: mvm: fix firmware debug restart recording
  iwlwifi: tt: move ucode_loaded check under mutex
  iwlwifi: mvm: support ibss in dqa mode
  iwlwifi: mvm: Fix command queue number on d0i3 flow
  iwlwifi: mvm: rs: start using LQ command color
  ...

Pull sparc fixes from David Miller:

 1) Fix TLB context wrap races, from Pavel Tatashin.

 2) Cure some gcc-7 build issues.

 3) Handle invalid setup_hugepagesz command line values properly, from
    Liam R Howlett.

 4) Copy TSB using the correct address shift for the huge TSB, from Mike
    Kravetz.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: delete old wrap code
  sparc64: new context wrap
  sparc64: add per-cpu mm of secondary contexts
  sparc64: redefine first version
  sparc64: combine activate_mm and switch_mm
  sparc64: reset mm cpumask after wrap
  sparc/mm/hugepages: Fix setup_hugepagesz for invalid values.
  sparc: Machine description indices can vary
  sparc64: mm: fix copy_tsb to correctly copy huge page TSBs
  arch/sparc: support NR_CPUS = 4096
  sparc64: Add __multi3 for gcc 7.x and later.
  sparc64: Fix build warnings with gcc 7.
  arch/sparc: increase CONFIG_NODES_SHIFT on SPARC64 to 5

GCC explicitly does not warn for unused static inline functions for
-Wunused-function.  The manual states:

	Warn whenever a static function is declared but not defined or
	a non-inline static function is unused.

Clang does warn for static inline functions that are unused.

It turns out that suppressing the warnings avoids potentially complex
#ifdef directives, which also reduces LOC.

Suppress the warning for clang.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pavel Tatashin says:

====================
sparc64: context wrap fixes

This patch series contains fixes for context wrap: when we are out of
context ids, and need to get a new version.

It fixes memory corruption issues which happen when more than number of
context ids (currently set to 8K) number of processes are started
simultaneously, and processes can get a wrong context.

sparc64: new context wrap:
- contains explanation of new wrap method, and also explanation of races
  that it solves
sparc64: reset mm cpumask after wrap
- explains issue of not reseting cpu mask on a wrap
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The old method that is using xcall and softint to get new context id is
deleted, as it is replaced by a method of using per_cpu_secondary_mm
without xcall to perform the context wrap.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The current wrap implementation has a race issue: it is called outside of
the ctx_alloc_lock, and also does not wait for all CPUs to complete the
wrap.  This means that a thread can get a new context with a new version
and another thread might still be running with the same context. The
problem is especially severe on CPUs with shared TLBs, like sun4v. I used
the following test to very quickly reproduce the problem:
- start over 8K processes (must be more than context IDs)
- write and read values at a  memory location in every process.

Very quickly memory corruptions start happening, and what we read back
does not equal what we wrote.

Several approaches were explored before settling on this one:

Approach 1:
Move smp_new_mmu_context_version() inside ctx_alloc_lock, and wait for
every process to complete the wrap. (Note: every CPU must WAIT before
leaving smp_new_mmu_context_version_client() until every one arrives).

This approach ends up with deadlocks, as some threads own locks which other
threads are waiting for, and they never receive softint until these threads
exit smp_new_mmu_context_version_client(). Since we do not allow the exit,
deadlock happens.

Approach 2:
Handle wrap right during mondo interrupt. Use etrap/rtrap to enter into
into C code, and issue new versions to every CPU.
This approach adds some overhead to runtime: in switch_mm() we must add
some checks to make sure that versions have not changed due to wrap while
we were loading the new secondary context. (could be protected by PSTATE_IE
but that degrades performance as on M7 and older CPUs as it takes 50 cycles
for each access). Also, we still need a global per-cpu array of MMs to know
where we need to load new contexts, otherwise we can change context to a
thread that is going way (if we received mondo between switch_mm() and
switch_to() time). Finally, there are some issues with window registers in
rtrap() when context IDs are changed during CPU mondo time.

The approach in this patch is the simplest and has almost no impact on
runtime.  We use the array with mm's where last secondary contexts were
loaded onto CPUs and bump their versions to the new generation without
changing context IDs. If a new process comes in to get a context ID, it
will go through get_new_mmu_context() because of version mismatch. But the
running processes do not need to be interrupted. And wrap is quicker as we
do not need to xcall and wait for everyone to receive and complete wrap.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The new wrap is going to use information from this array to figure out
mm's that currently have valid secondary contexts setup.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

CTX_FIRST_VERSION defines the first context version, but also it defines
first context. This patch redefines it to only include the first context
version.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The only difference between these two functions is that in activate_mm we
unconditionally flush context. However, there is no need to keep this
difference after fixing a bug where cpumask was not reset on a wrap. So, in
this patch we combine these.
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After a wrap (getting a new context version) a process must get a new
context id, which means that we would need to flush the context id from
the TLB before running for the first time with this ID on every CPU. But,
we use mm_cpumask to determine if this process has been running on this CPU
before, and this mask is not reset after a wrap. So, there are two possible
fixes for this issue:

1. Clear mm cpumask whenever mm gets a new context id
2. Unconditionally flush context every time process is running on a CPU

This patch implements the first solution
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

hugetlb_bad_size needs to be called on invalid values.  Also change the
pr_warn to a pr_err to better align with other platforms.
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

VIO devices were being looked up by their index in the machine
description node block, but this often varies over time as devices are
added and removed. Instead, store the ID and look up using the type,
config handle and ID.
Signed-off-by: James Clarke <jrtc27@jrtc27.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112541Signed-off-by: David S. Miller <davem@davemloft.net>

When a TSB grows beyond its current capacity, a new TSB is allocated
and copy_tsb is called to copy entries from the old TSB to the new.
A hash shift based on page size is used to calculate the index of an
entry in the TSB.  copy_tsb has hard coded PAGE_SHIFT in these
calculations.  However, for huge page TSBs the value REAL_HPAGE_SHIFT
should be used.  As a result, when copy_tsb is called for a huge page
TSB the entries are placed at the incorrect index in the newly
allocated TSB.  When doing hardware table walk, the MMU does not
match these entries and we end up in the TSB miss handling code.
This code will then create and write an entry to the correct index
in the TSB.  We take a performance hit for the table walk miss and
recreation of these entries.

Pass a new parameter to copy_tsb that is the page size shift to be
used when copying the TSB.
Suggested-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Linux SPARC64 limits NR_CPUS to 4064 because init_cpu_send_mondo_info()
only allocates a single page for NR_CPUS mondo entries. Thus we cannot
use all 4096 CPUs on some SPARC platforms.

To fix, allocate (2^order) pages where order is set according to the size
of cpu_list for possible cpus. Since cpu_list_pa and cpu_mondo_block_pa
are not used in asm code, there are no imm13 offsets from the base PA
that will break because they can only reach one page.

Orabug: 25505750
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Atish Patra <atish.patra@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit fb9a307d ("bpf: Allow CGROUP_SKB eBPF program to
access sk_buff") enabled programs of BPF_PROG_TYPE_CGROUP_SKB
type to use ld_abs/ind instructions. However, at this point,
we cannot use them, since offsets relative to SKF_LL_OFF will
end up pointing skb_mac_header(skb) out of bounds since in the
egress path it is not yet set at that point in time, but only
after __dev_queue_xmit() did a general reset on the mac header.
bpf_internal_load_pointer_neg_helper() will then end up reading
data from a wrong offset.

BPF_PROG_TYPE_CGROUP_SKB programs can use bpf_skb_load_bytes()
already to access packet data, which is also more flexible than
the insns carried over from cBPF.

Fixes: fb9a307d ("bpf: Allow CGROUP_SKB eBPF program to access sk_buff")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Chenbo Feng <fengc@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The check that queue is less or equal to zero is always true
because queue is a u32; queue is decremented and will wrap around
and never go -ve. Fix this by making queue an int.

Detected by CoverityScan, CID#1428988 ("Unsigned compared against 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

stmmac_tso_allocator can fail to set the Last Descriptor bit
on a descriptor that actually was the last descriptor.

This happens when the buffer of the last descriptor ends
up having a size of exactly TSO_MAX_BUFF_SIZE.

When the IP eventually reaches the next last descriptor,
which actually has the bit set, the DMA will hang.

When the DMA hangs, we get a tx timeout, however,
since stmmac does not do a complete reset of the IP
in stmmac_tx_timeout, we end up in a state with
completely hung TX.
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Acked-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Acked-by: Alexandre TORGUE <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Tun actually expects a symmetric hash for queue selecting to work
correctly, otherwise packets belongs to a single flow may be
redirected to the wrong queue. So this patch switch to use
__skb_get_hash_symmetric().
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethoc_reset enables device interrupts, ethoc_interrupt may schedule a
NAPI poll before NAPI is enabled in the ethoc_open, which results in
device being unable to send or receive anything until it's closed and
reopened. In case the device is flooded with ingress packets it may be
unable to recover at all.
Move napi_enable above ethoc_reset in the ethoc_open to fix that.

Fixes: a1702857 ("net: Add support for the OpenCores 10/100 Mbps Ethernet MAC.")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Tobias Klauser <tklauser@distanz.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We might call br_afspec() with p == NULL which is a valid use case if
the action is on the bridge device itself, but the bridge tunnel code
dereferences the p pointer without checking, so check if p is null
first.
Reported-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Fixes: efa5356b ("bridge: per vlan dst_metadata netlink support")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The register bits used for the frame mode were masked with DSA (0x1)
instead of the mask value (0x3) in the 6085 implementation of
port_set_frame_mode. Fix this.

Fixes: 56995cbc ("net: dsa: mv88e6xxx: Refactor CPU and DSA port setup")
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit a47b70ea ("ravb: unmap descriptors when freeing rings") has
introduced the issue seen in [1] reproduced on H3ULCB board.

Fix this by relocating the RX skb ringbuffer free operation, so that
swiotlb page unmapping can be done first. Freeing of aligned TX buffers
is not relevant to the issue seen in [1]. Still, reposition TX free
calls as well, to have all kfree() operations performed consistently
_after_ dma_unmap_*()/dma_free_*().

[1] Console screenshot with the problem reproduced:

salvator-x login: root
root@salvator-x:~# ifconfig eth0 up
Micrel KSZ9031 Gigabit PHY e6800000.ethernet-ffffffff:00: \
       attached PHY driver [Micrel KSZ9031 Gigabit PHY]   \
       (mii_bus:phy_addr=e6800000.ethernet-ffffffff:00, irq=235)
IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
root@salvator-x:~#
root@salvator-x:~# ifconfig eth0 down

==================================================================
BUG: KASAN: use-after-free in swiotlb_tbl_unmap_single+0xc4/0x35c
Write of size 1538 at addr ffff8006d884f780 by task ifconfig/1649

CPU: 0 PID: 1649 Comm: ifconfig Not tainted 4.12.0-rc4-00004-g112eb072 #32
Hardware name: Renesas H3ULCB board based on r8a7795 (DT)
Call trace:
[<ffff20000808f11c>] dump_backtrace+0x0/0x3a4
[<ffff20000808f4d4>] show_stack+0x14/0x1c
[<ffff20000865970c>] dump_stack+0xf8/0x150
[<ffff20000831f8b0>] print_address_description+0x7c/0x330
[<ffff200008320010>] kasan_report+0x2e0/0x2f4
[<ffff20000831eac0>] check_memory_region+0x20/0x14c
[<ffff20000831f054>] memcpy+0x48/0x68
[<ffff20000869ed50>] swiotlb_tbl_unmap_single+0xc4/0x35c
[<ffff20000869fcf4>] unmap_single+0x90/0xa4
[<ffff20000869fd14>] swiotlb_unmap_page+0xc/0x14
[<ffff2000080a2974>] __swiotlb_unmap_page+0xcc/0xe4
[<ffff2000088acdb8>] ravb_ring_free+0x514/0x870
[<ffff2000088b25dc>] ravb_close+0x288/0x36c
[<ffff200008aaf8c4>] __dev_close_many+0x14c/0x174
[<ffff200008aaf9b4>] __dev_close+0xc8/0x144
[<ffff200008ac2100>] __dev_change_flags+0xd8/0x194
[<ffff200008ac221c>] dev_change_flags+0x60/0xb0
[<ffff200008ba2dec>] devinet_ioctl+0x484/0x9d4
[<ffff200008ba7b78>] inet_ioctl+0x190/0x194
[<ffff200008a78c44>] sock_do_ioctl+0x78/0xa8
[<ffff200008a7a128>] sock_ioctl+0x110/0x3c4
[<ffff200008365a70>] vfs_ioctl+0x90/0xa0
[<ffff200008365dbc>] do_vfs_ioctl+0x148/0xc38
[<ffff2000083668f0>] SyS_ioctl+0x44/0x74
[<ffff200008083770>] el0_svc_naked+0x24/0x28

The buggy address belongs to the page:
page:ffff7e001b6213c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffff7e001b6213e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8006d884f680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8006d884f700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8006d884f780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8006d884f800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8006d884f880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
Disabling lock debugging due to kernel taint
root@salvator-x:~#

Fixes: a47b70ea ("ravb: unmap descriptors when freeing rings")
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>