Commit Graph

173 Commits

Author SHA1 Message Date
Julian Wiedmann
125d7d3011 s390/qeth: sanitize ARP requests
The ARP_{ADD,REMOVE}_ENTRY cmd structs contain reserved fields.
Introduce a common helper that doesn't raw-copy the user-provided data
into the cmd, but only sets those fields that are strictly needed for
the command.

This also sets the correct command length for ARP_REMOVE_ENTRY.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:06 -07:00
Julian Wiedmann
9fae5c3b60 s390/qeth: fix initial operstate
Setting the carrier 'on' for an unregistered netdevice doesn't update
its operstate. Fix this by delaying the update until the netdevice has
been registered.

Fixes: 91cc98f51e ("s390/qeth: remove duplicated carrier state tracking")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
30356d0815 s390/qeth: unregister netdevice only when registered
qeth only registers its netdevice when the qeth device is first set
online. Thus a device that has never been set online will trigger
a WARN ("network todo 'hsi%d' but state 0") in unregister_netdev() when
removed.

Fix this by protecting the unregister step, just like we already protect
against repeated registering of the netdevice.

Fixes: d3d1b205e8 ("s390/qeth: allocate netdevice early")
Reported-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
e19e5be8b4 s390/qeth: sanitize strings in debug messages
As Documentation/s390/s390dbf.txt states quite clearly, using any
pointer in sprinf-formatted s390dbf debug entries is dangerous.
The pointers are dereferenced whenever the trace file is read from.
So if the referenced data has a shorter life-time than the trace file,
any read operation can result in a use-after-free.

So rip out all hazardous use of indirect data, and replace any usage of
dev_name() and such by the Bus ID number.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-03 10:44:05 -07:00
Julian Wiedmann
0aef8392d2 s390/qeth: add TSO support for L2 devices
Except for the new HW header id, this works just like TSO6 on L3 devices
and reuses all the existing data path support in qeth_xmit().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 11:27:01 -07:00
Julian Wiedmann
82bf5c0867 s390/qeth: add support for IPv6 TSO
This adds TSO6 support for L3 qeth devices.
Just like for standard IPv6 traffic, TSO6 doesn't use IP offload and
thus runs over the normal qeth_xmit() path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 11:27:01 -07:00
Julian Wiedmann
91cc98f51e s390/qeth: remove duplicated carrier state tracking
The netdevice is always available, apply any carrier state changes to it
without caching them.
On a STARTLAN event (ie. carrier-up), defer updating the state to
qeth_core_hardsetup_card() in the subsequent recovery action.

Also remove the carrier-state checks from the xmit routines. Stopping
transmission on carrier-down is the responsibility of upper-level code
(eg see dev_direct_xmit()).

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:08 -07:00
Julian Wiedmann
8f6637b878 s390/qeth: pass card pointer in iob callback
This allows us to remove the CARD_FROM_CDEV calls in the iob callbacks.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:07 -07:00
Julian Wiedmann
4fda335476 s390/qeth: convert layer attribute to enum
While the raw values are fixed due to their use in a sysfs attribute,
we can still use the proper QETH_DISCIPLINE_* enum within the driver.

Also move the initialization into qeth_set_initial_options(), along with
all other user-configurable fields.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 09:56:07 -07:00
Julian Wiedmann
ed47155bdc s390/qeth: fine-tune spinlocks
For quite a lot of code paths it's obvious that they will never run in
IRQ context. So replace their spin_lock_irqsave() calls with
spin_lock_irq().

While at it, get rid of the redundant card pointer in struct qeth_reply
that was used by qeth_send_control_data() to access the card's lock.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
69d7ce80df s390/qeth: remove qeth_hdr_chk_and_bounce()
Restructure the OSN xmit path to handle misaligned HW headers properly,
without shifting the packet data around.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
356156b60a s390/qeth: speed up TSO transmission
Switch TSO over to the faster transmit path, and remove all the unused
old TSO code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
e517b649b3 s390/qeth: prepare for copy-free TSO transmission
Add all the necessary TSO plumbing to the copy-less transmit path.
This includes calculating the right length of required protocol headers,
and always building a separate buffer element for the TSO headers.

A follow-up patch will then switch TSO traffic over to this path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
f231dc9dbd s390/qeth: limit csum offload erratum to L3 devices
Combined L3+L4 csum offload is only required for some L3 HW. So for
L2 devices, don't offload the IP header csum calculation.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reference-ID: JUP 394553
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
40e6a22584 s390/qeth: remove qeth_get_elements_no()
Convert the last remaining user of qeth_get_elements_no() to
qeth_count_elements(), so this helper can be removed.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:25 -07:00
Julian Wiedmann
fc69660bbd s390/qeth: move L2 xmit code to core module
We need the exact same transmit path for non-offload-eligible traffic on
L3 OSAs. So make it accessible from both sub-drivers.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-17 09:10:24 -07:00
Julian Wiedmann
f15cdaf237 s390/qeth: don't restrict qeth_card to DMA memory
Allocating the main qeth_card struct with GFP_DMA blocks us from moving
it into netdev_priv(). But the only reason why we need DMA memory is the
ccw1 structs embedded into each ccw channel. So extract those into
separate allocations, like we already do for the cmd buffers.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
45ca2fd646 s390/qeth: use qeth_setup_ccw() to set up all CCWs
Re-work the helper a little bit, so that it can be used for all CCWs
that qeth issues.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
73657a3e5b s390/qeth: extract helper for MPC protocol type
Just a little code deduplication.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 14:02:50 -07:00
Julian Wiedmann
a7c2f4a332 s390/qeth: add support for constrained HW headers
Some transmit modes require that the HW header is located in the same
page as the initial protocol headers in skb->data. Let callers specify
the size of this contiguous header range, and enforce it when building
the HW header.

While at it, apply some gentle renaming to the relevant L2 code so that
it matches the L3 code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
ba86ceee9d s390/qeth: merge linearize-check into HW header construction
When checking whether an skb needs to be linearized to fit into an IO
buffer, it's desirable to consider the skb's final size and layout
(ie. after the HW header was added). But a subsequent linearization can
then cause the re-positioned HW header to violate its alignment
restrictions.

Dealing with this situation in two different code paths is quite tricky.
This patch integrates a) linearize-check and b) HW header construction
into one 3 step-sequence:
1. evaluate how the HW header needs to be added (to identify if it takes
   up an additional buffer element), then
2. check if the required buffer elements exceed the device's limit.
   Linearize when necessary and re-evaluate the HW header placement.
3. Add the HW header in the best-possible way:
   a) push, without taking up an additional buffer element
   b) push, but consume another buffer element
   c) allocate a header object from the cache.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
d2a274b25b s390/qeth: add statistics for consumed buffer elements
Nowadays an skb fragment typically spans over multiple pages. So replace
the obsolete, SG-only 'fragments' counter with one that tracks the
consumed buffer elements. This is what actually matters for performance.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
72f219da79 s390/qeth: use core MTU range checking
qeth's ndo_change_mtu() only applies some trivial bounds checking. Set
up dev->min_mtu properly, so that dev_set_mtu() can do this for us.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
8ce7a9e064 s390/qeth: simplify max MTU handling
When the MPC initialization code discovers the HW-specific max MTU,
apply the resulting changes straight to the netdevice.

If this is the device's first initialization, also set its MTU
(HiperSockets: the max MTU; else: a layer-specific default value).
Then cap the current MTU by the new max MTU.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
92d2720969 s390/qeth: don't cache HW port number
The netdevice is always available now, so get the portno from there.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:30 -07:00
Julian Wiedmann
d3d1b205e8 s390/qeth: allocate netdevice early
Allocation of the netdevice is currently delayed until a qeth card first
goes online. This complicates matters in several places, where we need
to cache values instead of applying them straight to the netdevice.

Improve on this by moving the allocation up to where the qeth card
itself is created. This is also one step in direction of eventually
placing the qeth card into netdev_priv().

In all subsequent code, remove the now redundant checks whether
card->dev is valid.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-21 10:12:29 -07:00
Julian Wiedmann
09960b3a0a s390/qeth: clean up exported symbols
Remove some redundant EXPORTs. While at it, also move some L2-only
prototypes into the proper header file.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
86c0cdb9e0 s390/qeth: clean up Output Queue selection
Consolidate duplicated code, fix the misuse of RTN_UNSPEC and simplify
the handling of non-unicast traffic on IQD devices.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
f67a43a73b s390/qeth: remove unused buffer->aob pointer
Except for tracing, the pointer is not used.

At the same time, accessing it from qeth_qdio_output_handler() is racy:
whenever qeth_qdio_cq_handler() gets control, its call to
qeth_qdio_handle_aob() frees the AOB.

So the AOB pointer that qeth_qdio_output_handler() stores into 'buffer'
can go stale at any time, and trigger a use-after-free.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-12 16:42:39 -07:00
Julian Wiedmann
d025da9eb1 s390/qeth: consistently re-enable device features
commit e830baa9c3 ("qeth: restore device features after recovery") and
commit ce34435641 ("s390/qeth: rely on kernel for feature recovery")
made sure that the HW functions for device features get re-programmed
after recovery.

But we missed that the same handling is also required when a card is
first set offline (destroying all HW context), and then online again.
Fix this by moving the re-enable action out of the recovery-only path.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-30 21:19:48 +09:00
Julian Wiedmann
ce28867fd2 s390/qeth: don't clobber buffer on async TX completion
If qeth_qdio_output_handler() detects that a transmit requires async
completion, it replaces the pending buffer's metadata object
(qeth_qdio_out_buffer) so that this queue buffer can be re-used while
the data is pending completion.

Later when the CQ indicates async completion of such a metadata object,
qeth_qdio_cq_handler() tries to free any data associated with this
object (since HW has now completed the transfer). By calling
qeth_clear_output_buffer(), it erronously operates on the queue buffer
that _previously_ belonged to this transfer ... but which has been
potentially re-used several times by now.
This results in double-free's of the buffer's data, and failing
transmits as the buffer descriptor is scrubbed in mid-air.

The correct way of handling this situation is to
1. scrub the queue buffer when it is prepared for re-use, and
2. later obtain the data addresses from the async-completion notifier
   (ie. the AOB), instead of the queue buffer.

All this only affects qeth devices used for af_iucv HiperTransport.

Fixes: 0da9581ddb ("qeth: exploit asynchronous delivery of storage blocks")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-30 21:19:48 +09:00
Kittipon Meesompop
571f9dd802 s390/qeth: add IPv6 TX checksum offload support
Check if a qeth device supports IPv6 TX checksum offload, and advertise
NETIF_F_IPV6_CSUM accordingly. Add support for setting the relevant bits
in IPv6 packet descriptors.

Currently this has only limited use (ie. UDP, or Jumbo Frames). For any
TCP traffic with a standard MSS, the TCP checksum gets calculated
as part of the linear GSO segmentation.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop
a8155b009f s390/qeth: extend Checksum Offload Assists for IPv6
Add some wrappers to make the protocol-specific Assist code a little
more generic, and use them for sending protocol-agnostic commands in
the Checksum Offload Assist code.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:49 -04:00
Kittipon Meesompop
3aade31b2f s390/qeth: add stats counter for RX csum offload
This matches the statistics we gather for the TX offload path.

Signed-off-by: Kittipon Meesompop <kmeesomp@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Julian Wiedmann
b339c24ebf s390/qeth: disregard IPv4 header for RX csum offload
The kernel does its own validation of the IPv4 header checksum,
drivers/HW are not required to handle this.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Julian Wiedmann
6195b93661 s390/qeth: extract csum offload helpers
This consolidates the checksum offload code that was duplicated
over the two qeth subdrivers.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:48 -04:00
Julian Wiedmann
d4ac024688 s390/qeth: convert vlan spinlock to mutex
As the vid_list is only accessed from process context, there's no need to
protect it with a spinlock.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
Julian Wiedmann
7bcd64eb8c s390/qeth: skip QDIO queue handler indirection
Both qeth sub drivers use the same QDIO queue handlers, there's no need
to expose them via the driver's discipline. No functional change.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-27 13:38:47 -04:00
Julian Wiedmann
901e3f49fa s390/qeth: avoid control IO completion stalls
For control IO, qeth currently tracks the index of the buffer that it
expects to complete the next IO on each qeth_channel. If the channel
presents an IRQ while this buffer has not yet completed, no completion
processing for _any_ completed buffer takes place.
So if the 'next buffer' is skipped for any sort of reason* (eg. when it
is released due to error conditions, before the IO is started), the
buffer obviously won't switch to PROCESSED until it is eventually
allocated for a _different_ IO and completes.
Until this happens, all completion processing on that channel stalls
and pending requests possibly time out.

As a fix, remove the whole 'next buffer' logic and simply process any
IO buffer right when it completes. A channel will never have more than
one IO pending, so there's no risk of processing out-of-sequence.

*Note: currently just one location in the code really handles this problem,
       by advancing the 'next' index manually.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-22 14:42:31 -04:00
Julian Wiedmann
b1d5e36b41 s390/qeth: shrink qeth_ipaddr struct
Using up 8 bytes in every ipaddr object to store SETIP/DELIP flags is
rather wasteful. Except for takeover eligibility, the flag values all
just depend on the address type, so determine them on demand.

While at it reorder the struct to fill an alignment hole.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 13:10:05 -05:00
Julian Wiedmann
b9caa98c51 s390/qeth: simplify card look-up on IP notification
On an IP event, current code tries to determine if the netdev belongs
to a L3 card by walking all qeth cards in the system, and then all of
their VLAN devices too. Short-cut the whole thing by identifying a L3
device through its netdev_ops.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 13:10:05 -05:00
Julian Wiedmann
1c5b2216fb s390/qeth: fix SETIP command handling
send_control_data() applies some special handling to SETIP v4 IPA
commands. But current code parses *all* command types for the SETIP
command code. Limit the command code check to IPA commands.

Fixes: 5b54e16f1a ("qeth: do not spin for SETIP ip assist command")
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-09 14:30:23 -05:00
Ursula Braun
89271c65ed s390/qeth: fix underestimated count of buffer elements
For a memory range/skb where the last byte falls onto a page boundary
(ie. 'end' is of the form xxx...xxx001), the PFN_UP() part of the
calculation currently doesn't round up to the next PFN due to an
off-by-one error.
Thus qeth believes that the skb occupies one page less than it
actually does, and may select a IO buffer that doesn't have enough spare
buffer elements to fit all of the skb's data.
HW detects this as a malformed buffer descriptor, and raises an
exception which then triggers device recovery.

Fixes: 2863c61334 ("qeth: refactor calculation of SBALE count")
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-09 14:30:23 -05:00
Julian Wiedmann
a843383a3e s390/qeth: unionize next-hop field in qeth L3 header
The L3 packet descriptor's 'dest_addr' field is used for a different
purpose in RX descriptors. Clean up the hard-coded byte accesses and
try to be more self-documenting.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 15:23:45 -05:00
Julian Wiedmann
a65d141043 s390/qeth: recognize non-IP multicast on L3 transmit
When
1. an skb has no neighbour, and
2. skb->protocol is not IP[V6],

we select the skb's cast type based on its destination MAC address.

The multicast check is currently restricted to Multicast IP-mapped MACs.
Extend it to also cover non-IP Multicast MACs.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 15:23:45 -05:00
Julian Wiedmann
1f9791235b s390/qeth: clean up l3_get_cast_type()
Use the proper helpers to check for multicast IP addressing, and remove
some ancient Token Ring code.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 15:23:45 -05:00
Julian Wiedmann
19e36da61a s390/qeth: robustify qeth_get_ip_version()
Instead of assuming that skb->data points to the Ethernet header, use
the right helper and struct to access the Ethertype field.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 15:23:45 -05:00
Elena Reshetova
ae6959273a qeth: convert qeth_reply.refcnt from atomic_t to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable qeth_reply.refcnt is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
[jwi: removed the WARN_ONs. Use CONFIG_REFCOUNT_FULL if you care.]
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 15:23:44 -05:00
Julian Wiedmann
02f510f326 s390/qeth: update takeover IPs after configuration change
Any modification to the takeover IP-ranges requires that we re-evaluate
which IP addresses are takeover-eligible. Otherwise we might do takeover
for some addresses when we no longer should, or vice-versa.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-15 11:29:43 -05:00
Julian Wiedmann
7fbd9493f0 s390/qeth: apply takeover changes when mode is toggled
Just as for an explicit enable/disable, toggling the takeover mode also
requires that the IP addresses get updated. Otherwise all IPs that were
added to the table before the mode-toggle, get registered with the old
settings.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-15 11:29:42 -05:00