s390/iucv: use new address translation helpers

Use virt_to_dma32() and friends to properly convert virtual to physical and
physical to virtual addresses so that "make C=1" does not generate any
warnings anymore.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

net/af_iucv: fix virtual vs physical address confusion

Fix virtual vs physical address confusion. This does not fix a bug
since virtual and physical address spaces are currently the same.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240215080500.2616848-1-agordeev@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: keep sk->sk_forward_alloc as small as possible

Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast.

Each TCP socket can forward allocate up to 2 MB of memory, even after
flow became less active.

10,000 sockets can have reserved 20 GB of memory,
and we have no shrinker in place to reclaim that.

Instead of trying to reclaim the extra allocations in some places,
just keep sk->sk_forward_alloc values as small as possible.

This should not impact performance too much now we have per-cpu
reserves: Changes to tcp_memory_allocated should not be too frequent.

For sockets not using SO_RESERVE_MEM:
- idle sockets (no packets in tx/rx queues) have zero forward alloc.
- non idle sockets have a forward alloc smaller than one page.

Note:

- Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD
is left to MPTCP maintainers as a follow up.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: remove noblock parameter from skb_recv_datagram()

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Don't include filter.h from net/sock.h

sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org

net/af_iucv: Use struct_group() to zero struct iucv_sock region

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark the region of struct iucv_sock that gets
initialized to zero. Avoid the future warning:

In function 'fortify_memset_chk',
inlined from 'iucv_sock_alloc' at net/iucv/af_iucv.c:476:2:
./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
199 | __write_overflow_field(p_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Acked-by: Karsten Graul <kgraul@linux.ibm.com>
Link: https://lore.kernel.org/lkml/19ff61a0-0cda-6000-ce56-dc6b367c00d6@linux.ibm.com/
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: fix kernel doc comments

Fix kernel doc comments where appropriate, or remove incorrect kernel
doc indicators.

Acked-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: remove wrappers around iucv (de-)registration

These wrappers are just unnecessary obfuscation.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: clean up a try_then_request_module()

Use IS_ENABLED(CONFIG_IUCV) to determine whether the iucv_if symbol
is available, and let depmod deal with the module dependency.

This was introduced back with commit 6fcd61f7bf5d ("af_iucv: use
loadable iucv interface"). And to avoid sprinkling IS_ENABLED() over
all the code, we're keeping the indirection through pr_iucv->...().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: support drop monitoring

Change the good paths to use consume_skb() instead of kfree_skb(). This
avoids flooding dropwatch with false-positives.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: clean up some forward declarations

The forward declarations for the iucv_handler callbacks are causing
various compile warnings with gcc-11. Reshuffle the code to get rid
of these prototypes.

Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: af_iucv.c: Couple of typo fixes

s/unitialized/uninitialized/
s/notifcations/notifications/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: build SG skbs for TRANS_HIPER sockets

The TX path no longer falls apart when some of its SG skbs are later
linearized by lower layers of the stack. So enable the use of SG skbs
in iucv_sock_sendmsg() again.

This effectively reverts
commit dc5367bcc556 ("net/af_iucv: don't use paged skbs for TX on HiperSockets").

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: don't track individual TX skbs for TRANS_HIPER sockets

Stop maintaining the skb_send_q list for TRANS_HIPER sockets.

Not only is it extra overhead, but keeping around a list of skb clones
means that we later also have to match the ->sk_txnotify() calls
against these clones and free them accordingly.
The current matching logic (comparing the skbs' shinfo location) is
frustratingly fragile, and breaks if the skb's head is mangled in any
sort of way while passing from dev_queue_xmit() to the device's
HW queue.

Also adjust the interface for ->sk_txnotify(), to make clear that we
don't actually care about any skb internals.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: count packets in the xmit path

The TX code keeps track of all skbs that are in-flight but haven't
actually been sent out yet. For native IUCV sockets that's not a huge
deal, but with TRANS_HIPER sockets it would be much better if we
didn't need to maintain a list of skb clones.

Note that we actually only care about the _count_ of skbs in this stage
of the TX pipeline. So as prep work for removing the skb tracking on
TRANS_HIPER sockets, keep track of the skb count in a separate variable
and pair any list {enqueue, unlink} with a count {increment, decrement}.

Then replace all occurences where we currently look at the skb list's
fill level.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: don't lookup the socket on TX notification

Whoever called iucv_sk(sk)->sk_txnotify() must already know that they're
dealing with an af_iucv socket.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: remove WARN_ONCE on malformed RX packets

syzbot reported the following finding:

AF_IUCV failed to receive skb, len=0
WARNING: CPU: 0 PID: 522 at net/iucv/af_iucv.c:2039 afiucv_hs_rcv+0x174/0x190 net/iucv/af_iucv.c:2039
CPU: 0 PID: 522 Comm: syz-executor091 Not tainted 5.10.0-rc1-syzkaller-07082-g55027a88ec9f #0
Hardware name: IBM 3906 M04 701 (KVM/Linux)
Call Trace:
[<00000000b87ea538>] afiucv_hs_rcv+0x178/0x190 net/iucv/af_iucv.c:2039
([<00000000b87ea534>] afiucv_hs_rcv+0x174/0x190 net/iucv/af_iucv.c:2039)
[<00000000b796533e>] __netif_receive_skb_one_core+0x13e/0x188 net/core/dev.c:5315
[<00000000b79653ce>] __netif_receive_skb+0x46/0x1c0 net/core/dev.c:5429
[<00000000b79655fe>] netif_receive_skb_internal+0xb6/0x220 net/core/dev.c:5534
[<00000000b796ac3a>] netif_receive_skb+0x42/0x318 net/core/dev.c:5593
[<00000000b6fd45f4>] tun_rx_batched.isra.0+0x6fc/0x860 drivers/net/tun.c:1485
[<00000000b6fddc4e>] tun_get_user+0x1c26/0x27f0 drivers/net/tun.c:1939
[<00000000b6fe0f00>] tun_chr_write_iter+0x158/0x248 drivers/net/tun.c:1968
[<00000000b4f22bfa>] call_write_iter include/linux/fs.h:1887 [inline]
[<00000000b4f22bfa>] new_sync_write+0x442/0x648 fs/read_write.c:518
[<00000000b4f238fe>] vfs_write.part.0+0x36e/0x5d8 fs/read_write.c:605
[<00000000b4f2984e>] vfs_write+0x10e/0x148 fs/read_write.c:615
[<00000000b4f29d0e>] ksys_write+0x166/0x290 fs/read_write.c:658
[<00000000b8dc4ab4>] system_call+0xe0/0x28c arch/s390/kernel/entry.S:415
Last Breaking-Event-Address:
[<00000000b8dc64d4>] __s390_indirect_jump_r14+0x0/0xc

Malformed RX packets shouldn't generate any warnings because
debugging info already flows to dropmon via the kfree_skb().

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: use DECLARE_SOCKADDR to cast from sockaddr

This gets us compile-time size checking.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: set correct sk_protocol for child sockets

Child sockets erroneously inherit their parent's sk_type (ie. SOCK_*),
instead of the PF_IUCV protocol that the parent was created with in
iucv_sock_create().

We're currently not using sk->sk_protocol ourselves, so this shouldn't
have much impact (except eg. getting the output in skb_dump() right).

Fixes: eac3731bd04c ("[S390]: Add AF_IUCV socket support")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Link: https://lore.kernel.org/r/20201120100657.34407-1-jwi@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: fix null pointer dereference on shutdown

syzbot reported the following KASAN finding:

BUG: KASAN: nullptr-dereference in iucv_send_ctrl+0x390/0x3f0 net/iucv/af_iucv.c:385
Read of size 2 at addr 000000000000021e by task syz-executor907/519

CPU: 0 PID: 519 Comm: syz-executor907 Not tainted 5.9.0-syzkaller-07043-gbcf9877ad213 #0
Hardware name: IBM 3906 M04 701 (KVM/Linux)
Call Trace:
[<00000000c576af60>] unwind_start arch/s390/include/asm/unwind.h:65 [inline]
[<00000000c576af60>] show_stack+0x180/0x228 arch/s390/kernel/dumpstack.c:135
[<00000000c9dcd1f8>] __dump_stack lib/dump_stack.c:77 [inline]
[<00000000c9dcd1f8>] dump_stack+0x268/0x2f0 lib/dump_stack.c:118
[<00000000c5fed016>] print_address_description.constprop.0+0x5e/0x218 mm/kasan/report.c:383
[<00000000c5fec82a>] __kasan_report mm/kasan/report.c:517 [inline]
[<00000000c5fec82a>] kasan_report+0x11a/0x168 mm/kasan/report.c:534
[<00000000c98b5b60>] iucv_send_ctrl+0x390/0x3f0 net/iucv/af_iucv.c:385
[<00000000c98b6262>] iucv_sock_shutdown+0x44a/0x4c0 net/iucv/af_iucv.c:1457
[<00000000c89d3a54>] __sys_shutdown+0x12c/0x1c8 net/socket.c:2204
[<00000000c89d3b70>] __do_sys_shutdown net/socket.c:2212 [inline]
[<00000000c89d3b70>] __s390x_sys_shutdown+0x38/0x48 net/socket.c:2210
[<00000000c9e36eac>] system_call+0xe0/0x28c arch/s390/kernel/entry.S:415

There is nothing to shutdown if a connection has never been established.
Besides that iucv->hs_dev is not yet initialized if a socket is in
IUCV_OPEN state and iucv->path is not yet initialized if socket is in
IUCV_BOUND state.
So, just skip the shutdown calls for a socket in these states.

Fixes: eac3731bd04c ("[S390]: Add AF_IUCV socket support")
Fixes: 82492a355fac ("af_iucv: add shutdown for HS transport")
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
[jwi: correct one Fixes tag]
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/af_iucv: right-size the uid variable in iucv_sock_bind()

smatch complains about
net/iucv/af_iucv.c:624 iucv_sock_bind() error: memcpy() 'sa->siucv_user_id' too small (8 vs 9)

Which is absolutely correct - the memcpy() takes 9 bytes (sizeof(uid))
from an 8-byte field (sa->siucv_user_id).
Luckily the sockaddr_iucv struct contains more data after the
.siucv_user_id field, and we checked the size of the passed data earlier
on. So the memcpy() won't accidentally read from an invalid location.

Fix the warning by reducing the size of the uid variable to what's
actually needed, and thus reducing the amount of copied data.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

net: pass a sockptr_t into ->setsockopt

Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer. This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: clean up function prototypes

Remove a bunch of forward declarations (trivially shifting code around
where needed), and make a few functions static.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: remove a redundant zero initialization

txmsg is declared as {0}, no need to clear individual fields later on.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: replace open-coded U16_MAX

Improve the readability of a range check.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: remove pm support

commit 394216275c7d ("s390: remove broken hibernate / power management support")
removed support for ARCH_HIBERNATION_POSSIBLE from s390.

So drop the unused pm ops from the s390-only af_iucv socket code.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Use sizeof_field() macro

Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().

This patch is generated using following script:

EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"

git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do

if [[ "$file" =~ $EXCLUDE_FILES ]]; then
continue
fi
sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done

Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net

net/af_iucv: mark expected switch fall-throughs

Mark switch cases where we are expecting to fall through.

This patch fixes the following warnings:

net/iucv/af_iucv.c: warning: this statement may fall
through [-Wimplicit-fallthrough=]: => 537:3, 519:6, 2246:6, 510:6

Notice that, in this particular case, the code comment is
modified in accordance with what GCC is expecting to find.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: always register net_device notifier

Even when running as VM guest (ie pr_iucv != NULL), af_iucv can still
open HiperTransport-based connections. For robust operation these
connections require the af_iucv_netdev_notifier, so register it
unconditionally.

Also handle any error that register_netdevice_notifier() returns.

Fixes: 9fbd87d41392 ("af_iucv: handle netdev events")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: build proper skbs for HiperTransport

The HiperSockets-based transport path in af_iucv is still too closely
entangled with qeth.
With commit a647a02512ca ("s390/qeth: speed-up L3 IQD xmit"), the
relevant xmit code in qeth has begun to use skb_cow_head(). So to avoid
unnecessary skb head expansions, af_iucv must learn to
1) respect dev->needed_headroom when allocating skbs, and
2) drop the header reference before cloning the skb.

While at it, also stop hard-coding the LL-header creation stage and just
use the appropriate helper.

Fixes: a647a02512ca ("s390/qeth: speed-up L3 IQD xmit")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: remove GFP_DMA restriction for HiperTransport

af_iucv sockets over z/VM IUCV require that their skbs are allocated
in DMA memory. This restriction doesn't apply to connections over
HiperSockets. So only set this limit for z/VM IUCV sockets, thereby
increasing the likelihood that the large (and linear!) allocations for
HiperTransport messages succeed.

Fixes: 3881ac441f64 ("af_iucv: add HiperSockets transport")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Add SPDX license identifier for more missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

iucv: Remove SKB list assumptions.

Eliminate the assumption that SKBs and SKB list heads can
be cast to eachother in SKB list handling code.

This change also appears to fix a bug since the list->next pointer is
sampled outside of holding the SKB queue lock.

Signed-off-by: David S. Miller <davem@davemloft.net>

Revert "net: simplify sock_poll_wait"

This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317.

This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: locate IUCV header via skb_network_header()

This patch attempts to untangle the TX and RX code in qeth from
af_iucv's respective HiperTransport path:
On the TX side, pointing skb_network_header() at the IUCV header
means that qeth_l3_fill_af_iucv_hdr() no longer needs a magical offset
to access the header.
On the RX side, qeth pulls the (fake) L2 header off the skb like any
normal ethernet driver would. This makes working with the IUCV header
in af_iucv easier, since we no longer have to assume a fixed skb layout.

While at it, replace the open-coded length checks in af_iucv's RX path
with pskb_may_pull().

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: iucv: Use FIELD_SIZEOF directly instead of reimplementing its function

FIELD_SIZEOF is defined as a macro to calculate the specified value. Therefore,
We prefer to use the macro rather than calculating its value.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: fix skb handling on HiperTransport xmit error

When sending an skb, afiucv_hs_send() bails out on various error
conditions. But currently the caller has no way of telling whether the
skb was freed or not - resulting in potentially either
a) leaked skbs from iucv_send_ctrl(), or
b) double-free's from iucv_sock_sendmsg().

As dev_queue_xmit() will always consume the skb (even on error), be
consistent and also free the skb from all other error paths. This way
callers no longer need to care about managing the skb.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/af_iucv: drop inbound packets with invalid flags

Inbound packets may have any combination of flag bits set in their iucv
header. If we don't know how to handle a specific combination, drop the
skb instead of leaking it.

To clarify what error is returned in this case, replace the hard-coded
0 with the corresponding macro.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net:af_iucv: get rid of the unneeded variable 'err' in afiucv_pm_freeze

We will not use the variable 'err' after initalization, So remove it and
return 0.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: simplify sock_poll_wait

The wait_address argument is always directly derived from the filp
argument, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove blank lines at end of file

Several files have extra line at end of file.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL

The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net/iucv: convert to ->poll_mask

Signed-off-by: Christoph Hellwig <hch@lst.de>

net/iucv: Free memory obtained by kzalloc

Free memory by calling put_device(), if afiucv_iucv_init is not
successful.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: make getname() functions return length rather than use int* parameter

Changes since v1:
Added changes in these files:
drivers/infiniband/hw/usnic/usnic_transport.c
drivers/staging/lustre/lnet/lnet/lib-socket.c
drivers/target/iscsi/iscsi_target_login.c
drivers/vhost/net.c
fs/dlm/lowcomms.c
fs/ocfs2/cluster/tcp.c
security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

text data bss dec hex filename
30108430 2633624 873672 33615726 200ef6e vmlinux.before.o
30108109 2633612 873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

vfs: do bulk POLL* -> EPOLL* replacement

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net: annotate ->poll() instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

iucv: Convert sk_wmem_alloc accesses to refcount_t.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Move sockaddr length checks to before accessing sa_family in bind and connect handlers

Verify that the caller-provided sockaddr structure is large enough to
contain the sa_family field, before accessing it in bind() and connect()
handlers of the AF_IUCV socket. Since neither syscall enforces a minimum
size of the corresponding memory region, very short sockaddrs (zero or
one byte long) result in operating on uninitialized memory while
referencing .sa_family.

Fixes: 52a82e23b9f2 ("af_iucv: Validate socket address length in iucv_sock_bind()")
Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>
[jwi: removed unneeded null-check for addr]
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/iucv: improve endianness handling

Use proper endianness conversion for an skb protocol assignment. Given
that IUCV is only available on big endian systems (s390), this simply
avoids an endianness warning reported by sparse.

Signed-off-by: Hans Wippel <hwippel@linux.vnet.ibm.com>
Reviewed-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Reviewed-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>

networking: make skb_push & __skb_push return void pointers

It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:

@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)

@@
expression E, SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)

@@
expression SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- fn(SKB, LEN)[0]
+ *(u8 *)fn(SKB, LEN)

Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Work around lockdep limitation in sockets that use sockets

Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

(1) If the pagefault handler decides it needs to read pages from AFS, it
calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
creating a call requires the socket lock:

mmap_sem must be taken before sk_lock-AF_RXRPC

(2) afs_open_socket() opens an AF_RXRPC socket and binds it. rxrpc_bind()
binds the underlying UDP socket whilst holding its socket lock.
inet_bind() takes its own socket lock:

sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

(3) Reading from a TCP socket into a userspace buffer might cause a fault
and thus cause the kernel to take the mmap_sem, but the TCP socket is
locked whilst doing this:

sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks. The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace. This is
a limitation in the design of lockdep.

Fix the general case by:

(1) Double up all the locking keys used in sockets so that one set are
used if the socket is created by userspace and the other set is used
if the socket is created by the kernel.

(2) Store the kern parameter passed to sk_alloc() in a variable in the
sock struct (sk_kern_sock). This informs sock_lock_init(),
sock_init_data() and sk_clone_lock() as to the lock keys to be used.

Note that the child created by sk_clone_lock() inherits the parent's
kern setting.

(3) Add a 'kern' parameter to ->accept() that is analogous to the one
passed in to ->create() that distinguishes whether kernel_accept() or
sys_accept4() was the caller and can be passed to sk_alloc().

Note that a lot of accept functions merely dequeue an already
allocated socket. I haven't touched these as the new socket already
exists before we get the parameter.

Note also that there are a couple of places where I've made the accepted
socket unconditionally kernel-based:

irda_accept()
rds_rcp_accept_one()
tcp_accept_from_sock()

because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal. I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

net/af_iucv: don't use paged skbs for TX on HiperSockets

With commit e53743994e21
("af_iucv: use paged SKBs for big outbound messages"),
we transmit paged skbs for both of AF_IUCV's transport modes
(IUCV or HiperSockets).
The qeth driver for Layer 3 HiperSockets currently doesn't
support NETIF_F_SG, so these skbs would just be linearized again
by the stack.
Avoid that overhead by using paged skbs only for IUCV transport.

cc stable, since this also circumvents a significant skb leak when
sending large messages (where the skb then needs to be linearized).

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # v4.8+
Fixes: e53743994e21 ("af_iucv: use paged SKBs for big outbound messages")
Signed-off-by: David S. Miller <davem@davemloft.net>

Subject: [PATCH] af_iucv: drop skbs rejected by filter

A packet filter might be installed for instance with setsockopt
SO_ATTACH_FILTER. af_iucv currently queues skbs rejected by filter
into the backlog queue. This does not make sense, since packets
rejected by filter can be dropped immediately. This patch adds
separate sk_filter return code checking, and dropping of packets
if applicable.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Subject: [PATCH] af_iucv: enable control sends in case of SEND_SHUTDOWN

If a socket program has shut down the socket for sending, it can still
receive an undetermined number of packets. The AF_IUCV protocol for
HIPER transport requires sending of a WIN flag from time to time
from the receiver to the sender, otherwise the peer cannot continue
sending. That means sending of control flags must still work, even
though the AF_IUCV socket is shutdown for sending data.
sock_alloc_send_skb() returns with error EPIPE, if socket sk_shutdown
is SEND_SHUTDOWN. Thus this patch temporarily removes the send
shutdown attribute from the socket to enable transfer of control
flags.

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: use paged SKBs for big inbound messages

When an inbound message is bigger than a page, allocate a paged SKB,
and subsequently use IUCV receive primitive with IPBUFLST flag.
This relaxes the pressure to allocate big contiguous kernel buffers.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: remove fragment_skb() to use paged SKBs

Before introducing paged skbs in the receive path, get rid of the
function `iucv_fragment_skb()` that replaces one large linear skb
with several smaller linear skbs.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: use paged SKBs for big outbound messages

When an outbound message is bigger than a page, allocate and fill
a paged SKB, and subsequently use IUCV send primitive with IPBUFLST
flag. This relaxes the pressure to allocate big contiguous kernel
buffers.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: properly clone LSM attributes to newly created child sockets

Much like we had to do for AF_BLUETOOTH and AF_ALG, make sure we
properly clone the parent socket's LSM attributes to newly created
child sockets.

Signed-off-by: Paul Moore <paul@paul-moore.com>

af_iucv: Validate socket address length in iucv_sock_bind()

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Evgeny Cherkashin <Eugene.Crosser@ru.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: call skb_linearize() when needed

When the linear buffer of the received sk_buff is shorter than
the header, use skb_linearize(). sk_buffs with short linear buffer
happen on the sending side under high traffic, and some kernel
configurations, when allocated buffer starts just before page
boundary, and IUCV transport has to send it as two separate QDIO
buffer elements, with fist element shorter than the header.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: prevent information leak in iucv_message

Initialize storage for the future IUCV header that will be included
in the transmitted packet. Some of the header fields are unused with
HiperSockets transport, and will contain data left from some other
functions.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA

This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Generalise wq_has_sleeper helper

The memory barrier in the helper wq_has_sleeper is needed by just
about every user of waitqueue_active. This patch generalises it
by making it take a wait_queue_head_t directly. The existing
helper is renamed to skwq_has_sleeper.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

s390/iucv: do not use arrays as argument

The iucv code uses arrays as arguments. Even though this does not
really cause a problem, it could be misleading, since the compiler
turns array arguments into just a pointer argument. To be more
precise this patch changes the array arguments into pointers.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Pass kern from net_proto_family.create to sk_alloc

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: fix AF_IUCV sendmsg() errno

When sending over AF_IUCV socket, errno was incorrectly set to
ENOMEM even when other values where appropriate, notably EAGAIN.
With this patch, error indicator returned by sock_alloc_send_skb()
is passed to the caller, rather than being overwritten with ENOMEM.

Signed-off-by: Eugene Crosser <Eugene.Crosser@ru.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove iocb argument from sendmsg and recvmsg

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: introduce helper macro for_each_cmsghdr

Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

new helper: memcpy_from_msg()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net: Add and use skb_copy_datagram_msg() helper.

This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: avoid path quiesce of severed path in shutdown()

An af_iucv stress test showed -EPIPE results for sendmsg()
calls. They are caused by quiescing a path even though it has
been already severed by peer. For IUCV transport shutdown()
consists of 2 steps:
(1) sending the shutdown message to peer
(2) quiescing the iucv path
If the iucv path between these 2 steps is severed due to peer
closing the path, the quiesce step is no longer needed.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Reported-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: remove unnecessary break after goto

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: correct cleanup if listen backlog is full

In case of transport HIPER a sock struct is allocated for an incoming
connect request. If the backlog queue is full this socket is not
needed, but is left in the list of af_iucv sockets. Final socket
release posts console message "Attempt to release alive iucv socket".
This patch makes sure the new created socket is cleaned up correctly
if the backlog queue is full.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Reported-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Add automatic (source) iucv_name to bind

If a socket is bound to an address using before calling connect
it is usual to leave it to the network system to choose an appropriate
outgoing application name respective port address.
af_iucv on VM uses a counter and uses simple numbers as unique identifiers.
This behaviour was missing when af_iucv is used with HiperSockets.

This patch contains a simple approach to harmonize af_iucv's behaviour.

Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: wrong mapping of sent and confirmed skbs

When sending data through IUCV a MESSAGE COMPLETE interrupt
signals that sent data memory can be freed or reused again.
With commit f9c41a62bba3f3f7ef3541b2a025e3371bcbba97
"af_iucv: fix recvmsg by replacing skb_pull() function" the
MESSAGE COMPLETE callback iucv_callback_txdone() identifies
the wrong skb as being confirmed, which leads to data corruption.
This patch fixes the skb mapping logic in iucv_callback_txdone().

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Fix use after free by removing length arg from sk_data_ready callbacks.

Several spots in the kernel perform a sequence like:

skb_queue_tail(&sk->s_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up. So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument. And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: recvmsg problem for SOCK_STREAM sockets

Commit f9c41a62bba3f3f7ef3541b2a025e3371bcbba97 introduced
a problem for SOCK_STREAM sockets, when only part of the
incoming iucv message is received by user space. In this
case the remaining data of the iucv message is lost.
This patch makes sure an incompletely received iucv message
is queued back to the receive queue.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reported-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rework recvmsg handler msg_name and msg_namelen logic

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: pass info struct via netdevice notifier

So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
shortened dev_getter
shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: fix recvmsg by replacing skb_pull() function

When receiving data messages, the "BUG_ON(skb->len < skb->data_len)" in
the skb_pull() function triggers a kernel panic.

Replace the skb_pull logic by a per skb offset as advised by
Eric Dumazet.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: Fix missing msg_namelen update in iucv_sock_recvmsg()

The current code does not fill the msg_name member in case it is set.
It also does not set the msg_namelen member to 0 and therefore makes
net/socket.c leak the local, uninitialized sockaddr_storage variable
to userland -- 128 bytes of kernel stack memory.

Fix that by simply setting msg_namelen to 0 as obviously nobody cared
about iucv_sock_recvmsg() not filling the msg_name in case it was set.

Cc: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: fix smatch warnings inside datagram_poll

Commit 7d4c04fc170087119727119074e72445f2bb192b ("net: add option to enable
error queue packets waking select") has an issue due to operator precedence
causing the bit-wise OR to bind to the sock_flags call instead of the result of
the terniary conditional. This fixes the *_poll functions to work properly. The
old code results in "mask |= POLLPRI" instead of what was intended, which is to
only include POLLPRI when the socket option is enabled.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add option to enable error queue packets waking select

Currently, when a socket receives something on the error queue it only wakes up
the socket on select if it is in the "read" list, that is the socket has
something to read. It is useful also to wake the socket if it is in the error
list, which would enable software to wait on error queue packets without waking
up for regular data on the socket. The main use case is for receiving
timestamped transmit packets which return the timestamp to the socket via the
error queue. This enables an application to select on the socket for the error
queue only instead of for the regular traffic.

-v2-
* Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file
* Modified every socket poll function that checks error queue

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Cc: Jeffrey Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Matthew Vick <matthew.vick@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

hlist: drop the node parameter from iterators

I'm not sure why, but the hlist for each entry iterators were conceived

list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net: remove skb_orphan_try()

Orphaning skb in dev_hard_start_xmit() makes bonding behavior
unfriendly for applications sending big UDP bursts : Once packets
pass the bonding device and come to real device, they might hit a full
qdisc and be dropped. Without orphaning, the sender is automatically
throttled because sk->sk_wmemalloc reaches sk->sk_sndbuf (assuming
sk_sndbuf is not too big)

We could try to defer the orphaning adding another test in
dev_hard_start_xmit(), but all this seems of little gain,
now that BQL tends to make packets more likely to be parked
in Qdisc queues instead of NIC TX ring, in cases where performance
matters.

Reverts commits :
fc6055a5ba31 net: Introduce skb_orphan_try()
87fd308cfc6b net: skb_tx_hash() fix relative to skb_orphan_try()
and removes SKBTX_DRV_NEEDS_SK_REF flag

Reported-and-bisected-by: Jean-Michel Hautbois <jhautbois@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: add shutdown for HS transport

AF_IUCV sockets offer a shutdown function. This patch makes sure
shutdown works for HS transport as well.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: handle netdev events

In case of transport through HiperSockets the underlying network
interface may switch to DOWN state or the underlying network device
may recover. In both cases the socket must change to IUCV_DISCONN
state. If the interface goes down, af_iucv has a chance to notify
its connection peer in addition.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: allow retrieval of maximum message size

For HS transport the maximum message size depends on the MTU-size
of the HS-device bound to the AF_IUCV socket. This patch adds a
getsockopt option MSGSIZE returning the maximum message size that
can be handled for this AF_IUCV socket.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: change net_device handling for HS transport

This patch saves the net_device in the iucv_sock structure during
bind in order to fasten skb sending.
In addition some other small improvements are made for HS transport:
- error checking when sending skbs
- locking changes in afiucv_hs_callback_txnotify
- skb freeing in afiucv_hs_callback_txnotify
And finally it contains code cleanup to get rid of iucv_skb_queue_purge.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: block writing if msg limit is exceeded

When polling on an AF_IUCV socket, writing should be blocked if the
number of pending messages exceeds a defined limit.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: remove IUCV-pathes completely

A SEVER is missing in the callback of a receiving SEVERED. This may
inhibit z/VM to remove the corresponding IUCV-path completely.
This patch adds a SEVER in iucv_callback_connrej (together with
additional locking.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: get rid of state IUCV_SEVERED

af_iucv differs unnecessarily between state IUCV_SEVERED and
IUCV_DISCONN. This patch removes state IUCV_SEVERED.
While simplifying af_iucv, this patch removes the 2nd invocation of
cpcmd as well.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: remove unused timer infrastructure

af_iucv contains timer infrastructure which is not exploited.
This patch removes the timer related code parts.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: release reference to HS device

For HiperSockets transport skbs sent are bound to one of the
available HiperSockets devices. Add missing release of reference to
a HiperSockets device before freeing an skb.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: accelerate close for HS transport

Closing an af_iucv socket may wait for confirmation of outstanding
send requests. This patch adds confirmation code for the new
HiperSockets transport.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: support ancillary data with HS transport

The AF_IUCV address family offers support for ancillary data.
This patch enables usage of ancillary data with the new
HiperSockets transport.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: more accurate skb truesize

skb truesize currently accounts for sk_buff struct and part of skb head.
kmalloc() roundings are also ignored.

Considering that skb_shared_info is larger than sk_buff, its time to
take it into account for better memory accounting.

This patch introduces SKB_TRUESIZE(X) macro to centralize various
assumptions into a single place.

At skb alloc phase, we put skb_shared_info struct at the exact end of
skb head, to allow a better use of memory (lowering number of
reallocations), since kmalloc() gives us power-of-two memory blocks.

Unless SLUB/SLUB debug is active, both skb->head and skb_shared_info are
aligned to cache lines, as before.

Note: This patch might trigger performance regressions because of
misconfigured protocol stacks, hitting per socket or global memory
limits that were previously not reached. But its a necessary step for a
more accurate memory accounting.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Andi Kleen <ak@linux.intel.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: add HiperSockets transport

The current transport mechanism for af_iucv is the z/VM offered
communications facility IUCV. To provide equivalent support when
running Linux in an LPAR, HiperSockets transport is added to the
AF_IUCV address family. It requires explicit binding of an AF_IUCV
socket to a HiperSockets device. A new packet_type ETH_P_AF_IUCV
is announced. An af_iucv specific transport header is defined
preceding the skb data. A small protocol is implemented for
connecting and for flow control/congestion management.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: cleanup - use iucv_sk(sk) early

Code cleanup making make use of local variable for struct iucv_sock.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: use loadable iucv interface

For future af_iucv extensions the module should be able to run in LPAR
mode too. For this we use the new dynamic loading iucv interface.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: get rid of compile warning

-Wunused-but-set-variable generates compile warnings. The affected
variables are removed.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

net/iucv: Add missing spin_unlock

Add a spin_unlock missing on the error path. There seems like no reason
why the lock should continue to be held if the kzalloc fail.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E1;
@@

* spin_lock(E1,...);
<+... when != E1
if (...) {
... when != E1
* return ...;
}
...+>
* spin_unlock(E1,...);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove unnecessary returns from void function()s

This patch removes from net/ (but not any netfilter files)
all the unnecessary return; statements that precede the
last closing brace of void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sock_def_readable() and friends RCU conversion

sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
need two atomic operations (and associated dirtying) per incoming
packet.

RCU conversion is pretty much needed :

1) Add a new structure, called "struct socket_wq" to hold all fields
that will need rcu_read_lock() protection (currently: a
wait_queue_head_t and a struct fasync_struct pointer).

[Future patch will add a list anchor for wakeup coalescing]

2) Attach one of such structure to each "struct socket" created in
sock_alloc_inode().

3) Respect RCU grace period when freeing a "struct socket_wq"

4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
socket_wq"

5) Change sk_sleep() function to use new sk->sk_wq instead of
sk->sk_sleep

6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
a rcu_read_lock() section.

7) Change all sk_has_sleeper() callers to :
- Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
- Use wq_has_sleeper() to eventually wakeup tasks.
- Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)

8) sock_wake_async() is modified to use rcu protection as well.

9) Exceptions :
macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
instead of dynamically allocated ones. They dont need rcu freeing.

Some cleanups or followups are probably needed, (possible
sk_callback_lock conversion to a spinlock for example...).

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sk_sleep() helper

Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

const: constify remaining dev_pm_ops

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net: pass kern to net_proto_family create function

The generic __sock_create function has a kern argument which allows the
security system to make decisions based on if a socket is being created by
the kernel or by userspace. This patch passes that flag to the
net_proto_family specific create function, so it can do the same thing.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: remove duplicate sock_set_flag

Remove duplicate sock_set_flag(sk, SOCK_ZAPPED) in iucv_sock_close,
which has been overlooked in September-commit
7514bab04e567c9408fe0facbde4277f09d5eb74.

Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: use sk functions to modify sk->sk_ack_backlog

Instead of modifying sk->sk_ack_backlog directly, use respective
socket functions.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mark net_proto_ops as const

All usages of structure net_proto_ops should be declared const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Make setsockopt() optlen be unsigned.

This provides safety against negative optlen at the type
level instead of depending upon (sometimes non-trivial)
checks against this sprinkled all over the the place, in
each and every implementation.

Based upon work done by Arjan van de Ven and feedback
from Linus Torvalds.

Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: fix race when queueing skbs on the backlog queue

iucv_sock_recvmsg() and iucv_process_message()/iucv_fragment_skb race
for dequeuing an skb from the backlog queue.

If iucv_sock_recvmsg() dequeues first, iucv_process_message() calls
sock_queue_rcv_skb() with an skb that is NULL.

This results in the following kernel panic:

<1>Unable to handle kernel pointer dereference at virtual kernel address (null)
<4>Oops: 0004 [#1] PREEMPT SMP DEBUG_PAGEALLOC
<4>Modules linked in: af_iucv sunrpc qeth_l3 dm_multipath dm_mod vmur qeth ccwgroup
<4>CPU: 0 Not tainted 2.6.30 #4
<4>Process client-iucv (pid: 4787, task: 0000000034e75940, ksp: 00000000353e3710)
<4>Krnl PSW : 0704000180000000 000000000043ebca (sock_queue_rcv_skb+0x7a/0x138)
<4> R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:0 PM:0 EA:3
<4>Krnl GPRS: 0052900000000000 000003e0016e0fe8 0000000000000000 0000000000000000
<4> 000000000043eba8 0000000000000002 0000000000000001 00000000341aa7f0
<4> 0000000000000000 0000000000007800 0000000000000000 0000000000000000
<4> 00000000341aa7f0 0000000000594650 000000000043eba8 000000003fc2fb28
<4>Krnl Code: 000000000043ebbe: a7840006 brc 8,43ebca
<4> 000000000043ebc2: 5930c23c c %r3,572(%r12)
<4> 000000000043ebc6: a724004c brc 2,43ec5e
<4> >000000000043ebca: e3c0b0100024 stg %r12,16(%r11)
<4> 000000000043ebd0: a7190000 lghi %r1,0
<4> 000000000043ebd4: e310b0200024 stg %r1,32(%r11)
<4> 000000000043ebda: c010ffffdce9 larl %r1,43a5ac
<4> 000000000043ebe0: e310b0800024 stg %r1,128(%r11)
<4>Call Trace:
<4>([<000000000043eba8>] sock_queue_rcv_skb+0x58/0x138)
<4> [<000003e0016bcf2a>] iucv_process_message+0x112/0x3cc [af_iucv]
<4> [<000003e0016bd3d4>] iucv_callback_rx+0x1f0/0x274 [af_iucv]
<4> [<000000000053a21a>] iucv_message_pending+0xa2/0x120
<4> [<000000000053b5a6>] iucv_tasklet_fn+0x176/0x1b8
<4> [<000000000014fa82>] tasklet_action+0xfe/0x1f4
<4> [<0000000000150a56>] __do_softirq+0x116/0x284
<4> [<0000000000111058>] do_softirq+0xe4/0xe8
<4> [<00000000001504ba>] irq_exit+0xba/0xd8
<4> [<000000000010e0b2>] do_extint+0x146/0x190
<4> [<00000000001184b6>] ext_no_vtime+0x1e/0x22
<4> [<00000000001fbf4e>] kfree+0x202/0x28c
<4>([<00000000001fbf44>] kfree+0x1f8/0x28c)
<4> [<000000000044205a>] __kfree_skb+0x32/0x124
<4> [<000003e0016bd8b2>] iucv_sock_recvmsg+0x236/0x41c [af_iucv]
<4> [<0000000000437042>] sock_aio_read+0x136/0x160
<4> [<0000000000205e50>] do_sync_read+0xe4/0x13c
<4> [<0000000000206dce>] vfs_read+0x152/0x15c
<4> [<0000000000206ed0>] SyS_read+0x54/0xac
<4> [<0000000000117c8e>] sysc_noemu+0x10/0x16
<4> [<00000042ff8def3c>] 0x42ff8def3c

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: do not call iucv_sock_kill() twice

For non-accepted sockets on the accept queue, iucv_sock_kill()
is called twice (in iucv_sock_close() and iucv_sock_cleanup_listen()).
This typically results in a kernel oops as shown below.

Remove the duplicate call to iucv_sock_kill() and set the SOCK_ZAPPED
flag in iucv_sock_close() only.

The iucv_sock_kill() function frees a socket only if the socket is zapped
and orphaned (sk->sk_socket == NULL):
- Non-accepted sockets are always orphaned and, thus, iucv_sock_kill()
frees the socket twice.
- For accepted sockets or sockets created with iucv_sock_create(),
sk->sk_socket is initialized. This caused the first call to
iucv_sock_kill() to return immediately. To free these sockets,
iucv_sock_release() uses sock_orphan() before calling iucv_sock_kill().

<1>Unable to handle kernel pointer dereference at virtual kernel address 000000003edd3000
<4>Oops: 0011 [#1] PREEMPT SMP DEBUG_PAGEALLOC
<4>Modules linked in: af_iucv sunrpc qeth_l3 dm_multipath dm_mod qeth vmur ccwgroup
<4>CPU: 0 Not tainted 2.6.30 #4
<4>Process iucv_sock_close (pid: 2486, task: 000000003aea4340, ksp: 000000003b75bc68)
<4>Krnl PSW : 0704200180000000 000003e00168e23a (iucv_sock_kill+0x2e/0xcc [af_iucv])
<4> R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
<4>Krnl GPRS: 0000000000000000 000000003b75c000 000000003edd37f0 0000000000000001
<4> 000003e00168ec62 000000003988d960 0000000000000000 000003e0016b0608
<4> 000000003fe81b20 000000003839bb58 00000000399977f0 000000003edd37f0
<4> 000003e00168b000 000003e00168f138 000000003b75bcd0 000000003b75bc98
<4>Krnl Code: 000003e00168e22a: c0c0ffffe6eb larl %r12,3e00168b000
<4> 000003e00168e230: b90400b2 lgr %r11,%r2
<4> 000003e00168e234: e3e0f0980024 stg %r14,152(%r15)
<4> >000003e00168e23a: e310225e0090 llgc %r1,606(%r2)
<4> 000003e00168e240: a7110001 tmll %r1,1
<4> 000003e00168e244: a7840007 brc 8,3e00168e252
<4> 000003e00168e248: d507d00023c8 clc 0(8,%r13),968(%r2)
<4> 000003e00168e24e: a7840009 brc 8,3e00168e260
<4>Call Trace:
<4>([<000003e0016b0608>] afiucv_dbf+0x0/0xfffffffffffdea20 [af_iucv])
<4> [<000003e00168ec6c>] iucv_sock_close+0x130/0x368 [af_iucv]
<4> [<000003e00168ef02>] iucv_sock_release+0x5e/0xe4 [af_iucv]
<4> [<0000000000438e6c>] sock_release+0x44/0x104
<4> [<0000000000438f5e>] sock_close+0x32/0x50
<4> [<0000000000207898>] __fput+0xf4/0x250
<4> [<00000000002038aa>] filp_close+0x7a/0xa8
<4> [<00000000002039ba>] SyS_close+0xe2/0x148
<4> [<0000000000117c8e>] sysc_noemu+0x10/0x16
<4> [<00000042ff8deeac>] 0x42ff8deeac

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: handle non-accepted sockets after resuming from suspend

After resuming from suspend, all af_iucv sockets are disconnected.
Ensure that iucv_accept_dequeue() can handle disconnected sockets
which are not yet accepted.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: fix race in __iucv_sock_wait()

Moving prepare_to_wait before the condition to avoid a race between
schedule_timeout and wake up.
The race can appear during iucv_sock_connect() and iucv_callback_connack().

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: constify remaining proto_ops

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: adding memory barrier to the poll and receive callbacks

Adding memory barrier after the poll_wait function, paired with
receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper
to wrap the memory barrier.

Without the memory barrier, following race can happen.
The race fires, when following code paths meet, and the tp->rcv_nxt
and __add_wait_queue updates stay in CPU caches.

CPU1 CPU2

sys_select receive packet
... ...
__add_wait_queue update tp->rcv_nxt
... ...
tp->rcv_nxt check sock_def_readable
... {
schedule ...
if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
wake_up_interruptible(sk->sk_sleep)
...
}

If there was no cache the code would work ok, since the wait_queue and
rcv_nxt are opposit to each other.

Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already
passed the tp->rcv_nxt check and sleeps, or will get the new value for
tp->rcv_nxt and will return with new data mask.
In both cases the process (CPU1) is being added to the wait queue, so the
waitqueue_active (CPU2) call cannot miss and will wake up CPU1.

The bad case is when the __add_wait_queue changes done by CPU1 stay in its
cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 will then
endup calling schedule and sleep forever if there are no more data on the
socket.

Calls to poll_wait in following modules were ommited:
net/bluetooth/af_bluetooth.c
net/irda/af_irda.c
net/irda/irnet/irnet_ppp.c
net/mac80211/rc80211_pid_debugfs.c
net/phonet/socket.c
net/rds/af_rds.c
net/rfkill/core.c
net/sunrpc/cache.c
net/sunrpc/rpc_pipe.c
net/tipc/socket.c

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Return -EAGAIN if iucv msg limit is exceeded

If the iucv message limit for a communication path is exceeded,
sendmsg() returns -EAGAIN instead of -EPIPE.
The calling application can then handle this error situtation,
e.g. to try again after waiting some time.

For blocking sockets, sendmsg() waits up to the socket timeout
before returning -EAGAIN. For the new wait condition, a macro
has been introduced and the iucv_sock_wait_state() has been
refactored to this macro.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Change if condition in sendmsg() for more readability

Change the if condition to exit sendmsg() if the socket in not connected.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[S390] PM: af_iucv power management callbacks.

Patch establishes a dummy afiucv-device to make sure af_iucv is
notified as iucv-bus device about suspend/resume.

The PM freeze callback severs all iucv pathes of connected af_iucv sockets.
The PM thaw/restore callback switches the state of all previously connected
sockets to IUCV_DISCONN.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

af_iucv: Fix merge.

From: Ursula Braun <ubraun@linux.vnet.ibm.com>

net/iucv/af_iucv.c in net-next-2.6 is almost correct. 4 lines should
still be deleted. These are the remaining changes:

Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: New socket option for setting IUCV MSGLIMITs

The SO_MSGLIMIT socket option modifies the message limit for new
IUCV communication paths.

The message limit specifies the maximum number of outstanding messages
that are allowed for connections. This setting can be lowered by z/VM
when an IUCV connection is established.

Expects an integer value in the range of 1 to 65535.
The default value is 65535.

The message limit must be set before calling connect() or listen()
for sockets.

If sockets are already connected or in state listen, changing the message
limit is not supported.
For reading the message limit value, unconnected sockets return the limit
that has been set or the default limit. For connected sockets, the actual
message limit is returned. The actual message limit is assigned by z/VM
for each connection and it depends on IUCV MSGLIMIT authorizations
specified for the z/VM guest virtual machine.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: cleanup and refactor recvmsg() EFAULT handling

If the skb cannot be copied to user iovec, always return -EFAULT.
The skb is enqueued again, except MSG_PEEK flag is set, to allow user space
applications to correct its iovec pointer.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Provide new socket type SOCK_SEQPACKET

This patch provides the socket type SOCK_SEQPACKET in addition to
SOCK_STREAM.

AF_IUCV sockets of type SOCK_SEQPACKET supports an 1:1 mapping of
socket read or write operations to complete IUCV messages.
Socket data or IUCV message data is not fragmented as this is the
case for SOCK_STREAM sockets.

The intention is to help application developers who write
applications or device drivers using native IUCV interfaces
(Linux kernel or z/VM IUCV interfaces).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Modify iucv msg target class using control msghdr

Allow 'classification' of socket data that is sent or received over
an af_iucv socket. For classification of data, the target class of an
(native) iucv message is used.

This patch provides the cmsg interface for iucv_sock_recvmsg() and
iucv_sock_sendmsg(). Applications can use the msg_control field of
struct msghdr to set or get the target class as a
"socket control message" (SCM/CMSG).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Support data in IUCV msg parameter lists (IPRMDATA)

The patch allows to send and receive data in the parameter list of an
iucv message.
The parameter list is an arry of 8 bytes that are used by af_iucv as
follows:
0..6 7 bytes for socket data and
7 1 byte to store the data length.

Instead of storing the data length directly, the difference
between 0xFF and the data length is used.
This convention does not interfere with the existing use of PRM
messages for shutting down the send direction of an AF_IUCV socket
(shutdown() operation). Data lenghts greater than 7 (or PRM message
byte 8 is less than 0xF8) denotes to special messages.
Currently, the special SEND_SHUTDOWN message is supported only.

To use IPRM messages, both communicators must set the IUCV_IPRMDATA
flag during path negotiation, i.e. in iucv_connect() and
path_pending().

To be compatible to older af_iucv implementations, sending PRM
messages is controlled by the socket option SO_IPRMDATA_MSG.
Receiving PRM messages does not depend on the socket option (but
requires the IUCV_IPRMDATA path flag to be set).

Sending/Receiving data in the parameter list improves performance for
small amounts of data by reducing message_completion() interrupts and
memory copy operations.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: add sockopt() to enable/disable use of IPRM_DATA msgs

Provide the socket operations getsocktopt() and setsockopt() to enable/disable
sending of data in the parameter list of IUCV messages.
The patch sets respective flag only.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: sync sk shutdown flag if iucv path is quiesced

If the af_iucv communication partner quiesces the path to shutdown its
receive direction, provide a quiesce callback implementation to shutdown
the (local) send direction. This ensures that both sides are synchronized.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Fix race when queuing incoming iucv messages

AF_IUCV runs into a race when queuing incoming iucv messages
and receiving the resulting backlog.

If the Linux system is under pressure (high load or steal time),
the message queue grows up, but messages are not received and queued
onto the backlog queue. In that case, applications do not
receive any data with recvmsg() even if AF_IUCV puts incoming
messages onto the message queue.

The race can be avoided if the message queue spinlock in the
message_pending callback is spreaded across the entire callback
function.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Test additional sk states in iucv_sock_shutdown

Add few more sk states in iucv_sock_shutdown().

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Reject incoming msgs if RECV_SHUTDOWN is set

Reject incoming iucv messages if the receive direction has been shut down.
It avoids that the queue of outstanding messages increases and exceeds the
message limit of the iucv communication path.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: fix oops in iucv_sock_recvmsg() for MSG_PEEK flag

If iucv_sock_recvmsg() is called with MSG_PEEK flag set, the skb is enqueued
twice. If the socket is then closed, the pointer to the skb is freed twice.

Remove the skb_queue_head() call for MSG_PEEK, because the skb_recv_datagram()
function already handles MSG_PEEK (does not dequeue the skb).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: consider state IUCV_CLOSING when closing a socket

Make sure a second invocation of iucv_sock_close() guarantees proper
freeing of an iucv path.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

iucv: remove some pointless conditionals before kfree_skb()

Remove some pointless conditionals before kfree_skb().

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Free iucv path/socket in path_pending callback

Free iucv path after iucv_path_sever() calls in iucv_callback_connreq()
(path_pending() iucv callback).
If iucv_path_accept() fails, free path and free/kill newly created socket.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: avoid left over IUCV connections from failing connects

For certain types of AFIUCV socket connect failures IUCV connections
are left over. Add some cleanup-statements to avoid cluttered IUCV
connections.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: New error return codes for connect()

If the iucv_path_connect() call fails then return an error code that
corresponds to the iucv_path_connect() failure condition; instead of
returning -ECONNREFUSED for any failure.

This helps to improve error handling for user space applications
(e.g. inform the user that the z/VM guest is not authorized to
connect to other guest virtual machines).

The error return codes are based on those described in connect(2).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[S390] convert iucv printks to dev_xxx and pr_xxx macros.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

[S390] Cleanup iucv printk messages.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

af_iucv: exploit target message class support of IUCV

The first 4 bytes of data to be sent are stored additionally into
the message class field of the send request. A receiving target
program (not an af_iucv socket program) can make use of this
information to pre-screen incoming messages.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_iucv: Use non-deprecated __RW_LOCK_UNLOCKED macro.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: defensive programming of iucv_callback_txdone

The loop in iucv_callback_txdone presumes existence of an entry
with msg->tag in the send_skb_q list. In error cases this
assumption might be wrong and might cause an endless loop.
Loop is rewritten to guarantee loop end in case of missing
msg->tag entry in send_skb_q.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: broken send_skb_q results in endless loop

A race has been detected in iucv_callback_txdone().
skb_unlink has to be done inside the locked area.

In addition checkings for successful allocations are inserted.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Convert init_timer into setup_timer

Many-many code in the kernel initialized the timer->function
and timer->data together with calling init_timer(timer). There
is already a helper for this. Use it for networking code.

The patch is HUGE, but makes the code 130 lines shorter
(98 insertions(+), 228 deletions(-)).

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Forget the zero_it argument of sk_alloc()

Finally, the zero_it argument can be completely removed from
the callers and from the function prototype.

Besides, fix the checkpatch.pl warnings about using the
assignments inside if-s.

This patch is rather big, and it is a part of the previous one.
I splitted it wishing to make the patches more readable. Hope
this particular split helped.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: postpone receival of iucv-packets

AF_IUCV socket programs may waste Linux storage, because af_iucv
allocates an skb whenever posted by the receive callback routine and
receives the message immediately.
Message receival is now postponed if data from previous callbacks has
not yet been transferred to the receiving socket program. Instead a
message handle is saved in a message queue as a reminder. Once
messages could be given to the receiving socket program, there is
an additional checking for entries in the message queue, followed
by skb allocation and message receival if applicable.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: remove static declarations from header file.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Make socket creation namespace safe.

This patch passes in the namespace a new socket should be created in
and has the socket code do the appropriate reference counting. By
virtue of this all socket create methods are touched. In addition
the socket create methods are modified so that they will fail if
you attempt to create a socket in a non-default network namespace.

Failing if we attempt to create a socket outside of the default
network namespace ensures that as we incrementally make the network stack
network namespace aware we will not export functionality that someone
has not audited and made certain is network namespace safe.
Allowing us to partially enable network namespaces before all of the
exotic protocols are supported.

Any protocol layers I have missed will fail to compile because I now
pass an extra parameter into the socket creation code.

[ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: Add lock when updating accept_q

The accept_queue of an af_iucv socket will be corrupted, if
adding and deleting of entries in this queue occurs at the
same time (connect request from one client, while accept call
is processed for another client).
Solution: add locking when updating accept_q

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Acked-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV]: Compile fix - adopt to skbuff changes.

From: Heiko Carstens <heiko.carstens@de.ibm.com>

CC [M] net/iucv/af_iucv.o
net/iucv/af_iucv.c: In function `iucv_fragment_skb':
net/iucv/af_iucv.c:984: error: structure has no member named `h'
net/iucv/af_iucv.c:985: error: structure has no member named `nh'
net/iucv/af_iucv.c:988: error: incompatible type for argument 1 of
`skb_queue_tail'

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[AF_IUCV/IUCV] : Add missing section annotations

Add missing section annotations and found and fixed some
Coding Style issues.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>

[AF_IUCV]: Implementation of a skb backlog queue

With the inital implementation we missed to implement a skb backlog
queue . The result is that socket receive processing tossed packets.
Since AF_IUCV connections are working synchronously it leads to
connection hangs. Problems with read, close and select also occured.

Using a skb backlog queue is fixing all of these problems .

Signed-off-by: Jennifer Hunt <jenhunt@us.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: cleanup extra semicolons

Spring cleaning time...

There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals. Most commonly is a
bogus semicolon after: switch() { }

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SK_BUFF]: Introduce skb_reset_transport_header(skb)

For the common, open coded 'skb->h.raw = skb->data' operation, so that we can
later turn skb->h.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple cases:

skb->h.raw = skb->data;
skb->h.raw = {skb_push|[__]skb_pull}()

The next ones will handle the slightly more "complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[SK_BUFF]: Introduce skb_reset_network_header(skb)

For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[S390]: Add AF_IUCV socket support

From: Jennifer Hunt <jenhunt@us.ibm.com>

This patch adds AF_IUCV socket support.

Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>