Kernel documentation of L2TP has not been kept up to date and lacks
coverage of some L2TP APIs. While addressing this, refactor to improve
readability, separating the parts which focus on user APIs and
internal implementation into sections.

Changes in v2:

 - fix checkpatch warnings about trailing whitespace and long lines
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We've been warning about SO_BSDCOMPAT usage for many years. We may remove
this code completely now.
Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Florian Fainelli says:

====================
net: dsa: loop: Expose VLAN table through devlink

Changes in v2:

- set the DSA configure_vlan_while_not_filtering boolean
- return the actual occupancy
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

We return the VLAN table size through devlink as a simple parameter, we
do not support altering it at runtime:

devlink resource show mdio_bus/fixed-0:1f
mdio_bus/fixed-0:1f:
  name VTU size 4096 occ 0 unit entry dpipe_tables none

and after configure a bridge with VLAN filtering:

devlink resource show mdio_bus/fixed-0:1f
mdio_bus/fixed-0:1f:
  name VTU size 4096 occ 1 unit entry dpipe_tables none
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since this is a mock-up driver with no real data path for now, but we
will have one at some point, enable VLANs while not filtering.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

The frags of skb_shared_info of the data is assigned in following loop. It
is meaningless to do a memcpy of frags here.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove a couple of unused #defines in cs89x0.h.
Signed-off-by: Alex Dewar <alex.dewar90@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Convert the uses of fallthrough comments to fallthrough macro.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Johannes Berg says:

====================
netlink: allow NLA_BINARY length range validation

In quite a few places (perhaps particularly in wireless) we need to
validation an NLA_BINARY attribute with both a minimum and a maximum
length. Currently, we can do either of the two, but not both, given
that we have NLA_MIN_LEN (minimum length) and NLA_BINARY (maximum).

Extend the range mechanisms that we use for integer validation to
apply to NLA_BINARY as well.

After converting everything to use NLA_POLICY_MIN_LEN() we can thus
get rid of the NLA_MIN_LEN type since that's now a special case of
NLA_BINARY with a minimum length validation. Similarly, NLA_EXACT_LEN
can be specified using NLA_POLICY_EXACT_LEN() and also maps to the
new NLA_BINARY validation (min == max == desired length).

Finally, NLA_POLICY_EXACT_LEN_WARN() also gets to be a somewhat
special case of this.

I haven't included the patch here now that converts nl82011 to use
this because it doesn't apply without another cleanup patch, but
we can remove a number of hand-coded min/max length checks and get
better error messages from the general validation code while doing
that.

As I had originally built the netlink policy export to userspace in
a way that has min/max length for NLA_BINARY (for the types that we
used to call NLA_MIN_LEN, NLA_BINARY and NLA_EXACT_LEN) anyway, it
doesn't really change anything there except that now there's a chance
that userspace sees min length < max length, which previously wasn't
possible.

v2:
 * fix the min<max comment to correctly say min<=max
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add range validation for NLA_BINARY, allowing validation of any
combination of combination minimum or maximum lengths, using the
existing NLA_POLICY_RANGE()/NLA_POLICY_FULL_RANGE() macros, just
like for integers where the value is checked.

Also make NLA_POLICY_EXACT_LEN(), NLA_POLICY_EXACT_LEN_WARN()
and NLA_POLICY_MIN_LEN() special cases of this, removing the old
types NLA_EXACT_LEN and NLA_MIN_LEN.

This allows us to save some code where both minimum and maximum
lengths are requires, currently the policy only allows maximum
(NLA_BINARY), minimum (NLA_MIN_LEN) or exact (NLA_EXACT_LEN), so
a range of lengths cannot be accepted and must be checked by the
code that consumes the attributes later.

Also, this allows advertising the correct ranges in the policy
export to userspace. Here, NLA_MIN_LEN and NLA_EXACT_LEN already
were special cases of NLA_BINARY with min and min/max length
respectively.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change places that open-code NLA_POLICY_MIN_LEN() to
use the macro instead, giving us flexibility in how we
handle the details of the macro.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Change places that open-code NLA_POLICY_EXACT_LEN() to
use the macro instead, giving us flexibility in how we
handle the details of the macro.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull mailmap update from Kees Cook:
 "This was originally part of my pstore tree, but when I realized that
  mailmap needed re-alphabetizing, I decided to wait until -rc1 to send
  this, as I saw a lot of mailmap additions pending in -next for the
  merge window.

  It's a programmatic reordering and the addition of a pstore
  contributor's preferred email address"

* tag 'pstore-v5.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  mailmap: Add WeiXiong Liao
  mailmap: Restore dictionary sorting

Pull networking fixes from David Miller:
 "Another batch of fixes:

  1) Remove nft_compat counter flush optimization, it generates warnings
     from the refcount infrastructure. From Florian Westphal.

  2) Fix BPF to search for build id more robustly, from Jiri Olsa.

  3) Handle bogus getopt lengths in ebtables, from Florian Westphal.

  4) Infoleak and other fixes to j1939 CAN driver, from Eric Dumazet and
     Oleksij Rempel.

  5) Reset iter properly on mptcp sendmsg() error, from Florian
     Westphal.

  6) Show a saner speed in bonding broadcast mode, from Jarod Wilson.

  7) Various kerneldoc fixes in bonding and elsewhere, from Lee Jones.

  8) Fix double unregister in bonding during namespace tear down, from
     Cong Wang.

  9) Disable RP filter during icmp_redirect selftest, from David Ahern"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (75 commits)
  otx2_common: Use devm_kcalloc() in otx2_config_npa()
  net: qrtr: fix usage of idr in port assignment to socket
  selftests: disable rp_filter for icmp_redirect.sh
  Revert "net: xdp: pull ethernet header off packet after computing skb->protocol"
  phylink: <linux/phylink.h>: fix function prototype kernel-doc warning
  mptcp: sendmsg: reset iter on error redux
  net: devlink: Remove overzealous WARN_ON with snapshots
  tipc: not enable tipc when ipv6 works as a module
  tipc: fix uninit skb->data in tipc_nl_compat_dumpit()
  net: Fix potential wrong skb->protocol in skb_vlan_untag()
  net: xdp: pull ethernet header off packet after computing skb->protocol
  ipvlan: fix device features
  bonding: fix a potential double-unregister
  can: j1939: add rxtimer for multipacket broadcast session
  can: j1939: abort multipacket broadcast session when timeout occurs
  can: j1939: cancel rxtimer on multipacket broadcast session complete
  can: j1939: fix support for multipacket broadcast message
  net: fddi: skfp: cfm: Remove seemingly unused variable 'ID_sccs'
  net: fddi: skfp: cfm: Remove set but unused variable 'oldstate'
  net: fddi: skfp: smt: Remove seemingly unused variable 'ID_sccs'
  ...

A multiplication for the size determination of a memory allocation
indicated that an array data structure should be processed.
Thus use the corresponding function "devm_kcalloc".
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

Passing large uint32 sockaddr_qrtr.port numbers for port allocation
triggers a warning within idr_alloc() since the port number is cast
to int, and thus interpreted as a negative number. This leads to
the rejection of such valid port numbers in qrtr_port_assign() as
idr_alloc() fails.

To avoid the problem, switch to idr_alloc_u32() instead.

Fixes: bdabad3e ("net: Add Qualcomm IPC router")
Reported-by: syzbot+f31428628ef672716ea8@syzkaller.appspotmail.com
Signed-off-by: Necip Fazil Yildiran <necip@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

h1 is initially configured to reach h2 via r1 rather than the
more direct path through r2. If rp_filter is set and inherited
for r2, forwarding fails since the source address of h1 is
reachable from eth0 vs the packet coming to it via r1 and eth1.
Since rp_filter setting affects the test, explicitly reset it.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

WeiXiong Liao noted to me offlist that his preference for email address
had changed and that he'd like it updated in the mailmap so people
discussing pstore/blk would be able to reach him.

Cc: WeiXiong Liao <gmpy.liaowx@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>

Several names had been recently appended (instead of inserted). While
git-shortlog doesn't need this file to be sorted, it helps humans to
keep it organized this way. Sort the entire file (which includes some
minor shuffling for dictionary order).

Done with the following commands:

	grep -E '^(#|$)' .mailmap > .mailmap.head
	grep -Ev '^(#|$)' .mailmap > .mailmap.body
 	sort -f .mailmap.body > .mailmap.body.sort
	cat .mailmap.head .mailmap.body.sort > .mailmap
	rm .mailmap.head .mailmap.body.sort
Signed-off-by: Kees Cook <keescook@chromium.org>

This reverts commit f8414a8d.

eth_type_trans() does the necessary pull on the skb.
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix a kernel-doc warning for the pcs_config() function prototype:

../include/linux/phylink.h:406: warning: Excess function parameter 'permit_pause_to_mac' description in 'pcs_config'

Fixes: 7137e18f ("net: phylink: add struct phylink_pcs")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

Impose a limit on the number of watches that a user can hold so that
they can't use this mechanism to fill up all the available memory.

This is done by putting a counter in user_struct that's incremented when
a watch is allocated and decreased when it is released.  If the number
exceeds the RLIMIT_NOFILE limit, the watch is rejected with EAGAIN.

This can be tested by the following means:

 (1) Create a watch queue and attach it to fd 5 in the program given - in
     this case, bash:

	keyctl watch_session /tmp/nlog /tmp/gclog 5 bash

 (2) In the shell, set the maximum number of files to, say, 99:

	ulimit -n 99

 (3) Add 200 keyrings:

	for ((i=0; i<200; i++)); do keyctl newring a$i @s || break; done

 (4) Try to watch all of the keyrings:

	for ((i=0; i<200; i++)); do echo $i; keyctl watch_add 5 %:a$i || break; done

     This should fail when the number of watches belonging to the user hits
     99.

 (5) Remove all the keyrings and all of those watches should go away:

	for ((i=0; i<200; i++)); do keyctl unlink %:a$i; done

 (6) Kill off the watch queue by exiting the shell spawned by
     watch_session.

Fixes: c73be61c ("pipe: Add general notification queue support")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This fix wasn't correct: When this function is invoked from the
retransmission worker, the iterator contains garbage and resetting
it causes a crash.

As the work queue should not be performance critical also zero the
msghdr struct.

Fixes: 35759383 "(mptcp: sendmsg: reset iter on error)"
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is possible to trigger this WARN_ON from user space by triggering a
devlink snapshot with an ID which already exists. We don't need both
-EEXISTS being reported and spamming the kernel log.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Chris Healy <cphealy@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When using ipv6_dev_find() in one module, it requires ipv6 not to
work as a module. Otherwise, this error occurs in build:

  undefined reference to `ipv6_dev_find'.

So fix it by adding "depends on IPV6 || IPV6=n" to tipc/Kconfig,
as it does in sctp/Kconfig.

Fixes: 5a6f6f57 ("tipc: set ub->ifindex for local ipv6 address")
Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

__tipc_nl_compat_dumpit() has two callers, and it expects them to
pass a valid nlmsghdr via arg->data. This header is artificial and
crafted just for __tipc_nl_compat_dumpit().

tipc_nl_compat_publ_dump() does so by putting a genlmsghdr as well
as some nested attribute, TIPC_NLA_SOCK. But the other caller
tipc_nl_compat_dumpit() does not, this leaves arg->data uninitialized
on this call path.

Fix this by just adding a similar nlmsghdr without any payload in
tipc_nl_compat_dumpit().

This bug exists since day 1, but the recent commit 6ea67769
("net: tipc: prepare attrs in __tipc_nl_compat_dumpit()") makes it
easier to appear.

Reported-and-tested-by: syzbot+0e7181deafa7e0b79923@syzkaller.appspotmail.com
Fixes: d0796d1e ("tipc: convert legacy nl bearer dump to nl compat")
Cc: Jon Maloy <jmaloy@redhat.com>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Richard Alpe <richard.alpe@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Endianness issue in IPv4 option support in nft_exthdr,
   from Stephen Suryaputra.

2) Removes the waitcount optimization in nft_compat,
   from Florian Westphal.

3) Remove ipv6 -> nf_defrag_ipv6 module dependency, from
   Florian Westphal.

4) Memleak in chain binding support, also from Florian.

5) Simplify nft_flowtable.sh selftest, from Fabian Frederick.

6) Optional MTU arguments for selftest nft_flowtable.sh,
   also from Fabian.

7) Remove noise error report when killing process in
   selftest nft_flowtable.sh, from Fabian Frederick.

8) Reject bogus getsockopt option length in ebtables,
   from Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'linux-can-fixes-for-5.9-20200815' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2020-08-15

this is a pull request of 4 patches for net/master.

All patches are by Zhang Changzhong and fix broadcast related problems in the
j1939 CAN networking stack.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

We may access the two bytes after vlan_hdr in vlan_set_encap_proto(). So
we should pull VLAN_HLEN + sizeof(unsigned short) in skb_vlan_untag() or
we may access the wrong data.

Fixes: 0d5501c1 ("net: Always untag vlan-tagged traffic on input.")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When an XDP program changes the ethernet header protocol field,
eth_type_trans is used to recalculate skb->protocol. In order for
eth_type_trans to work correctly, the ethernet header must actually be
part of the skb data segment, so the code first pushes that onto the
head of the skb. However, it subsequently forgets to pull it back off,
making the behavior of the passed-on packet inconsistent between the
protocol modifying case and the static protocol case. This patch fixes
the issue by simply pulling the ethernet header back off of the skb
head.

Fixes: 29724956 ("net: fix generic XDP to handle if eth header was mangled")
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Processing NETDEV_FEAT_CHANGE causes IPvlan links to lose
NETIF_F_LLTX feature because of the incorrect handling of
features in ipvlan_fix_features().

--before--
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~# ethtool -K ipvl0 tso off
Cannot change tcp-segmentation-offload
Actual changes:
vlan-challenged: off [fixed]
tx-lockless: off [fixed]
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: off [fixed]
lpaa10:~#

--after--
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~# ethtool -K ipvl0 tso off
Cannot change tcp-segmentation-offload
Could not change any device features
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~#

Fixes: 2ad7bf36 ("ipvlan: Initial check-in of the IPVLAN driver.")
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When we tear down a network namespace, we unregister all
the netdevices within it. So we may queue a slave device
and a bonding device together in the same unregister queue.

If the only slave device is non-ethernet, it would
automatically unregister the bonding device as well. Thus,
we may end up unregistering the bonding device twice.

Workaround this special case by checking reg_state.

Fixes: 9b5e383c ("net: Introduce unregister_netdevice_many()")
Reported-by: syzbot+af23e7f3e0a7e10c8b67@syzkaller.appspotmail.com
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull io_uring fixes from Jens Axboe:
 "A few differerent things in here.

  Seems like syzbot got some more io_uring bits wired up, and we got a
  handful of reports and the associated fixes are in here.

  General fixes too, and a lot of them marked for stable.

  Lastly, a bit of fallout from the async buffered reads, where we now
  more easily trigger short reads. Some applications don't really like
  that, so the io_read() code now handles short reads internally, and
  got a cleanup along the way so that it's now easier to read (and
  documented). We're now passing tests that failed before"

* tag 'io_uring-5.9-2020-08-15' of git://git.kernel.dk/linux-block:
  io_uring: short circuit -EAGAIN for blocking read attempt
  io_uring: sanitize double poll handling
  io_uring: internally retry short reads
  io_uring: retain iov_iter state over io_read/io_write calls
  task_work: only grab task signal lock when needed
  io_uring: enable lookup of links holding inflight files
  io_uring: fail poll arm on queue proc failure
  io_uring: hold 'ctx' reference around task_work queue + execute
  fs: RWF_NOWAIT should imply IOCB_NOIO
  io_uring: defer file table grabbing request cleanup for locked requests
  io_uring: add missing REQ_F_COMP_LOCKED for nested requests
  io_uring: fix recursive completion locking on oveflow flush
  io_uring: use TWA_SIGNAL for task_work uncondtionally
  io_uring: account locked memory before potential error case
  io_uring: set ctx sq/cq entry count earlier
  io_uring: Fix NULL pointer dereference in loop_rw_iter()
  io_uring: add comments on how the async buffered read retry works
  io_uring: io_async_buf_func() need not test page bit

Commit 1355c31e ("asm-generic: pgalloc: provide generic pmd_alloc_one()
and pmd_free_one()") converted parisc to use generic version of
pmd_alloc_one() but it missed the fact that parisc uses order-1 pages for
PMD.

Restore the original version of pmd_alloc_one() for parisc, just use
GFP_PGTABLE_KERNEL that implies __GFP_ZERO instead of GFP_KERNEL and
memset.

Fixes: 1355c31e ("asm-generic: pgalloc: provide generic pmd_alloc_one() and pmd_free_one()")
Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lkml.kernel.org/r/9f2b5ebd-e4a4-0fa1-6cd3-4b9f6892d1ad@linux.eeSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull block fixes from Jens Axboe:
 "A few fixes on the block side of things:

   - Discard granularity fix (Coly)

   - rnbd cleanups (Guoqing)

   - md error handling fix (Dan)

   - md sysfs fix (Junxiao)

   - Fix flush request accounting, which caused an IO slowdown for some
     configurations (Ming)

   - Properly propagate loop flag for partition scanning (Lennart)"

* tag 'block-5.9-2020-08-14' of git://git.kernel.dk/linux-block:
  block: fix double account of flush request's driver tag
  loop: unset GENHD_FL_NO_PART_SCAN on LOOP_CONFIGURE
  rnbd: no need to set bi_end_io in rnbd_bio_map_kern
  rnbd: remove rnbd_dev_submit_io
  md-cluster: Fix potential error pointer dereference in resize_bitmaps()
  block: check queue's limits.discard_granularity in __blkdev_issue_discard()
  md: get sysfs entry after redundancy attr group create

Pull RISC-V fix from Palmer Dabbelt:
 "I collected a single fix during the merge window: we managed to break
  the early trap setup on !MMU, this fixes it"

* tag 'riscv-for-linus-5.9-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Setup exception vector for nommu platform

Pull arch/sh updates from Rich Felker:
 "Cleanup, SECCOMP_FILTER support, message printing fixes, and other
  changes to arch/sh"

* tag 'sh-for-5.9' of git://git.libc.org/linux-sh: (34 commits)
  sh: landisk: Add missing initialization of sh_io_port_base
  sh: bring syscall_set_return_value in line with other architectures
  sh: Add SECCOMP_FILTER
  sh: Rearrange blocks in entry-common.S
  sh: switch to copy_thread_tls()
  sh: use the generic dma coherent remap allocator
  sh: don't allow non-coherent DMA for NOMMU
  dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig
  sh: unexport register_trapped_io and match_trapped_io_handler
  sh: don't include <asm/io_trapped.h> in <asm/io.h>
  sh: move the ioremap implementation out of line
  sh: move ioremap_fixed details out of <asm/io.h>
  sh: remove __KERNEL__ ifdefs from non-UAPI headers
  sh: sort the selects for SUPERH alphabetically
  sh: remove -Werror from Makefiles
  sh: Replace HTTP links with HTTPS ones
  arch/sh/configs: remove obsolete CONFIG_SOC_CAMERA*
  sh: stacktrace: Remove stacktrace_ops.stack()
  sh: machvec: Modernize printing of kernel messages
  sh: pci: Modernize printing of kernel messages
  ...

One case was missed in the short IO retry handling, and that's hitting
-EAGAIN on a blocking attempt read (eg from io-wq context). This is a
problem on sockets that are marked as non-blocking when created, they
don't carry any REQ_F_NOWAIT information to help us terminate them
instead of perpetually retrying.

Fixes: 227c0c96 ("io_uring: internally retry short reads")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

There's a bit of confusion on the matching pairs of poll vs double poll,
depending on if the request is a pure poll (IORING_OP_POLL_ADD) or
poll driven retry.

Add io_poll_get_double() that returns the double poll waitqueue, if any,
and io_poll_get_single() that returns the original poll waitqueue. With
that, remove the argument to io_poll_remove_double().

Finally ensure that wait->private is cleared once the double poll handler
has run, so that remove knows it's already been seen.

Cc: stable@vger.kernel.org # v5.8
Reported-by: syzbot+7f617d4a9369028b8a2c@syzkaller.appspotmail.com
Fixes: 18bceab1 ("io_uring: allow POLL_ADD with double poll_wait() users")
Signed-off-by: Jens Axboe <axboe@kernel.dk>