[ Upstream commit 3ef7cf57c72f32f61e97f8fa401bc39ea1f1a5d4 ]

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 89ab066d4229acd32e323f1569833302544a4186 ]

This reverts commit dd979b4d.

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: NKarsten Graul <kgraul@linux.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The wait_address argument is always directly derived from the filp
argument, so remove it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a missing rcu_read_unlock in the error path

Fixes: c95567c8 ("caif: added check for potential null return")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NLinus Torvalds <torvalds@linux-foundation.org>

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

Trivial fix to spelling mistake
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Init method just allocates memory for new cfg, and
assigns net_generic(net, caif_net_id). Despite there is
synchronize_rcu() on error path in cfcnfg_create(),
in real this function does not use global lists,
so it looks like this synchronize_rcu() is some legacy
inheritance. Exit method removes caif devices under
rtnl_lock().

There could be a problem, if someone from foreign net
pernet_operations dereference caif_net_id of this net.
It's dereferenced in get_cfcnfg() and caif_device_list().

get_cfcnfg() is used from netdevice notifiers, where
they are called under rtnl_lock(). The notifiers can't
be called from foreign nets pernet_operations. Also,
it's used from caif_disconnect_client() and from
caif_connect_client(). The both of the functions work
with caif socket, and there is the only possibility
to have a socket, when the net is dead. This may happen
only of the socket was created as kern using sk_alloc().
Grep by PF_CAIF shows we do not create kern caif sockets,
so get_cfcnfg() is safe.

caif_device_list() is used in netdevice notifiers and exit
method under rtnl lock. Also, from caif_get() used in
the netdev notifiers and in caif_flow_cb(). The last item
is skb destructor. Since there are no kernel caif sockets
nobody can send net a packet in parallel with init/exit,
so this is also safe.

So, these pernet_operations are safe to be async.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When CONFIG_KASAN is set, we can use relatively large amounts of kernel
stack space:

net/caif/cfctrl.c:555:1: warning: the frame size of 1600 bytes is larger than 1280 bytes [-Wframe-larger-than=]

This adds convenience wrappers around cfpkt_extr_head(), which is responsible
for most of the stack growth. With those wrapper functions, gcc apparently
starts reusing the stack slots for each instance, thus avoiding the
problem.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The CAIF channel connection request parameters need to be copied to/from
userspace. In support of usercopy hardening, this patch defines a region
in the struct proto slab cache in which userspace copy operations are
allowed.

example usage trace:

    net/caif/caif_socket.c:
        setsockopt(...):
            ...
            copy_from_user(&cf_sk->conn_req.param.data, ..., ol)

This region is known as the slab cache's usercopy region. Slab caches
can now check that each dynamically sized copy operation involving
cache-managed memory falls entirely within the slab's usercopy region.

This patch is modified from Brad Spengler/PaX Team's PAX_USERCOPY
whitelisting code in the last public patch of grsecurity/PaX based on my
understanding of the code. Changes or omissions from the original code are
mine and don't reflect the original grsecurity/PaX code.
Signed-off-by: NDavid Windsor <dave@nullcore.net>
[kees: split from network patch, provide usage trace]
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>

gcc-8 reports

net/caif/caif_usb.c: In function 'cfusbl_device_notify':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

The compiler require that the input param 'len' of strncpy() should be
greater than the length of the src string, so that '\0' is copied as
well. We can just use strlcpy() to avoid this warning.
Signed-off-by: NXiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gcc-8 reports

net/caif/caif_dev.c: In function 'caif_enroll_dev':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfctrl.c: In function 'cfctrl_linkup_request':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfcnfg.c: In function 'caif_connect_client':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

The compiler require that the input param 'len' of strncpy() should be
greater than the length of the src string, so that '\0' is copied as
well. We can just use strlcpy() to avoid this warning.
Signed-off-by: NXiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Preempt counter APIs have been split out, currently, hardirq.h just
includes irq_enter/exit APIs which are not used by caif at all.

So, remove the unused hardirq.h.
Signed-off-by: NYang Shi <yang.s@alibaba-inc.com>
Cc: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: NKate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: NPhilippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: NElena Reshetova <elena.reshetova@intel.com>
Signed-off-by: NHans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid Windsor <dwindsor@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for extended error reporting.
Signed-off-by: NMatthias Schiffer <mschiffer@universe-factory.net>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for extended error reporting.
Signed-off-by: NMatthias Schiffer <mschiffer@universe-factory.net>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Verify that the caller-provided sockaddr structure is large enough to
contain the sa_family field, before accessing it in the connect()
handler of the AF_CAIF socket. Since the syscall doesn't enforce 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.
Signed-off-by: NMateusz Jurczyk <mjurczyk@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kernel may sleep under a rcu read lock in cfpkt_create_pfx, and the
function call path is:
cfcnfg_linkup_rsp (acquire the lock by rcu_read_lock)
  cfctrl_linkdown_req
    cfpkt_create
      cfpkt_create_pfx
        alloc_skb(GFP_KERNEL) --> may sleep
cfserl_receive (acquire the lock by rcu_read_lock)
  cfpkt_split
    cfpkt_create_pfx
      alloc_skb(GFP_KERNEL) --> may sleep

There is "in_interrupt" in cfpkt_create_pfx to decide use "GFP_KERNEL" or
"GFP_ATOMIC". In this situation, "GFP_KERNEL" is used because the function
is called under a rcu read lock, instead in interrupt.

To fix it, only "GFP_ATOMIC" is used in cfpkt_create_pfx.
Signed-off-by: NJia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Network devices can allocate reasources and private memory using
netdev_ops->ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops->ndo_uninit() or netdev->destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops->ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev->destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev->destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops->ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops->ndo_uninit().  But
it is not able to invoke netdev->destructor().

This is because netdev->destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev->destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev->destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev->priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev->destructor(), except for
free_netdev().

netdev->needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit()
and netdev->priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev->priv_destructor() and optionally call free_netdev().
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: Nlinzhang <xiaolou4617@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.
Acked-by: NLinus 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: NIngo Molnar <mingo@kernel.org>

The stats member of struct chnl_net is used nowhere in the code, so it
might as well be removed.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The check of the return value of sock_register() is ineffective.
"if(!err)" seems to be a typo. It is better to propagate the error code
to the callers of caif_sktinit_module(). This patch removes the check
statment and directly returns the result of sock_register().

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=188751Signed-off-by: NPan Bian <bianpan2016@163.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some of the pr_* messages are missing spaces, so insert these and also
unbreak multi-line literal strings in pr_* messages
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop redundant include of moduleparam.h

The Coccinelle semantic patch used to make this change is as follows:
@ includesmodule @
@@

#include <linux/module.h>

@ depends on includesmodule @
@@

- #include <linux/moduleparam.h>
Signed-off-by: NAmitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gcc points out code that is not indented the way it is
interpreted:

net/caif/cfpkt_skbuff.c: In function 'cfpkt_setlen':
net/caif/cfpkt_skbuff.c:289:4: error: statement is indented as if it were guarded by... [-Werror=misleading-indentation]
    return cfpkt_getlen(pkt);
    ^~~~~~
net/caif/cfpkt_skbuff.c:286:3: note: ...this 'else' clause, but it is not
   else
   ^~~~

It is clear from the context that not returning here would be
a bug, as we'd end up passing a negative length into a function
that takes a u16 length, so it is not missing curly braces
here, and I'm assuming that the indentation is the only part
that's wrong about it.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The cfrfml_receive() function might return positive value EPROTO
Signed-off-by: NAnton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Signed-off-by: NPhil Sutter <phil@nwl.cc>
Cc: Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1) If sk_filter() is applied, skb was leaked (not freed)
2) Testing SOCK_DEAD twice is racy :
   packet could be freed while already queued.
3) Remove obsolete comment about caching skb->len
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

got a rare NULL pointer dereference in clear_bit
Signed-off-by: NMark Salyzyn <salyzyn@android.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
----
v2: switch to sock_flag(sk, SOCK_DEAD) and added net/caif/caif_socket.c
v3: return -ECONNRESET in upstream caller of wait function for SOCK_DEAD
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

It should be checking flags, not msg->msg_flags.  It's ->sendmsg()
instances that need to look for that in ->msg_flags, ->recvmsg() ones
(including the other ->recvmsg() instance in that file, as well as
unix_dgram_recvmsg() this one claims to be imitating) check in flags.
Braino had been introduced in commit dcda13 ("caif: Bugfix - use MSG_TRUNC
in receive") back in 2010, so it goes quite a while back.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The cfpkt_iterate() function can return -EPROTO on error, but the
function is a u16 so the negative value gets truncated to a positive
unsigned short.  This causes a static checker warning.

The only caller which might care is cffrml_receive(), when it's checking
the frame checksum.  I modified cffrml_receive() so that it never says
-EPROTO is a valid checksum.

Also this isn't ever going to be inlined so I removed the "inline".
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>