kmalloc() of sufficiently big portion of memory is cache-aligned
in regular conditions. If some debugging options are used,
there is no reason qdisc structures would need 64-byte alignment
if most other kernel structures are not aligned.

This get rid of QDISC_ALIGN and QDISC_ALIGNTO.

Addition of privdata field will help implementing
the reverse of qdisc_priv() and documents where
the private data is.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Allen Pais <allen.lkml@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

In case of errors, this message was printed:

  (...)
  balanced bwidth with unbalanced delay       5233 max 5005  [ fail ]
  client exit code 0, server 0
  \nnetns ns3-0-EwnkPH socket stat for 10003:
  (...)

Obviously, the idea was to add a new line before the socket stat and not
print "\nnetns".

The commit 8b974778 ("selftests: mptcp: interpret \n as a new line")
is very similar to this one. But the modification in simult_flows.sh was
missed because this commit above was done in parallel to one here below.

Fixes: 1a418cb8 ("mptcp: simult flow self-tests")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Without these definitions, the driver will crash in:
mscc_ocelot_probe
-> ocelot_init
   -> ocelot_vcap_init
     -> __ocelot_target_read_ix

I missed this because I did not have the VSC7514 hardware to test, only
the VSC9959 and VSC9953, and the probing part is different.

Fixes: e3aea296 ("net: mscc: ocelot: add definitions for VCAP ES0 keys, actions and target")
Fixes: a61e365d ("net: mscc: ocelot: add definitions for VCAP IS1 keys, actions and target")
Reported-by: Divya Koppera <Divya.Koppera@microchip.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

If recvmsg() and the workqueue race to dequeue the data
pending on some subflow, the current mapping for such
subflow covers several skbs and some of them have not
reached yet the received, either the worker or recvmsg()
can find a subflow with the data_avail flag set - since
the current mapping is valid and in sequence - but no
skbs in the receive queue - since the other entity just
processed them.

The above will lead to an unbounded loop in __mptcp_move_skbs()
and a subsequent hang of any task trying to acquiring the msk
socket lock.

This change addresses the issue stopping the __mptcp_move_skbs()
loop as soon as we detect the above race (empty receive queue
with data_avail set).

Reported-and-tested-by: syzbot+fcf8ca5817d6e92c6567@syzkaller.appspotmail.com
Fixes: ab174ad8 ("mptcp: move ooo skbs into msk out of order queue.")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

In preparation for unconditionally passing the
struct tasklet_struct pointer to all tasklet
callbacks, switch to using the new tasklet_setup()
and from_tasklet() to pass the tasklet pointer explicitly.
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Signed-off-by: Allen Pais <apais@linux.microsoft.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This accidentally got wired up to the *get* policy instead
of the *set* policy, causing operations to be rejected. Fix
it by wiring up the correct policy instead.

Fixes: 5028588b ("ethtool: wire up set policies to ops")
Reported-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Tested-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The ETHTOOL_A_STRSET_COUNTS_ONLY flag attribute was previously
not allowed to be used, but now due to the policy size reduction
we would access the tb[] array out of bounds since we tried to
check for the attribute despite it not being accepted.

Fix both issues by adding it correctly to the appropriate policy.

Fixes: ff419afa ("ethtool: trim policy tables")
Fixes: 71921690 ("ethtool: provide string sets with STRSET_GET request")
Reported-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Tested-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Small conflict around locking in rxrpc_process_event() -
channel_lock moved to bundle in next, while state lock
needs _bh() from net.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull vhost fixes from Michael Tsirkin:
 "Some last minute vhost,vdpa fixes.

  The last two of them haven't been in next but they do seem kind of
  obvious, very small and safe, fix bugs reported in the field, and they
  are both in a new mlx5 vdpa driver, so it's not like we can introduce
  regressions"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vdpa/mlx5: Fix dependency on MLX5_CORE
  vdpa/mlx5: should keep avail_index despite device status
  vhost-vdpa: fix page pinning leakage in error path
  vhost-vdpa: fix vhost_vdpa_map() on error condition
  vhost: Don't call log_access_ok() when using IOTLB
  vhost: Use vhost_get_used_size() in vhost_vring_set_addr()
  vhost: Don't call access_ok() when using IOTLB
  vhost vdpa: fix vhost_vdpa_open error handling

Pull networking fixes from Jakub Kicinski:
 "One more set of fixes from the networking tree:

   - add missing input validation in nl80211_del_key(), preventing
     out-of-bounds access

   - last minute fix / improvement of a MRP netlink (uAPI) interface
     introduced in 5.9 (current) release

   - fix "unresolved symbol" build error under CONFIG_NET w/o
     CONFIG_INET due to missing tcp_timewait_sock and inet_timewait_sock
     BTF.

   - fix 32 bit sub-register bounds tracking in the bpf verifier for OR
     case

   - tcp: fix receive window update in tcp_add_backlog()

   - openvswitch: handle DNAT tuple collision in conntrack-related code

   - r8169: wait for potential PHY reset to finish after applying a FW
     file, avoiding unexpected PHY behaviour and failures later on

   - mscc: fix tail dropping watermarks for Ocelot switches

   - avoid use-after-free in macsec code after a call to the GRO layer

   - avoid use-after-free in sctp error paths

   - add a device id for Cellient MPL200 WWAN card

   - rxrpc fixes:
      - fix the xdr encoding of the contents read from an rxrpc key
      - fix a BUG() for a unsupported encoding type.
      - fix missing _bh lock annotations.
      - fix acceptance handling for an incoming call where the incoming
        call is encrypted.
      - the server token keyring isn't network namespaced - it belongs
        to the server, so there's no need. Namespacing it means that
        request_key() fails to find it.
      - fix a leak of the server keyring"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (21 commits)
  net: usb: qmi_wwan: add Cellient MPL200 card
  macsec: avoid use-after-free in macsec_handle_frame()
  r8169: consider that PHY reset may still be in progress after applying firmware
  openvswitch: handle DNAT tuple collision
  sctp: fix sctp_auth_init_hmacs() error path
  bridge: Netlink interface fix.
  net: wireless: nl80211: fix out-of-bounds access in nl80211_del_key()
  bpf: Fix scalar32_min_max_or bounds tracking
  tcp: fix receive window update in tcp_add_backlog()
  net: usb: rtl8150: set random MAC address when set_ethernet_addr() fails
  mptcp: more DATA FIN fixes
  net: mscc: ocelot: warn when encoding an out-of-bounds watermark value
  net: mscc: ocelot: divide watermark value by 60 when writing to SYS_ATOP
  net: qrtr: ns: Fix the incorrect usage of rcu_read_lock()
  rxrpc: Fix server keyring leak
  rxrpc: The server keyring isn't network-namespaced
  rxrpc: Fix accept on a connection that need securing
  rxrpc: Fix some missing _bh annotations on locking conn->state_lock
  rxrpc: Downgrade the BUG() for unsupported token type in rxrpc_read()
  rxrpc: Fix rxkad token xdr encoding
  ...

Remove propmt for selecting MLX5_VDPA by the user and modify
MLX5_VDPA_NET to select MLX5_VDPA. Also modify MLX5_VDPA_NET to depend
on mlx5_core.

This fixes an issue where configuration sets 'y' for MLX5_VDPA_NET while
MLX5_CORE is compiled as a module causing link errors.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 1a86b377 ("vdpa/mlx5: Add VDPA driver for supported mlx5 device")s
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20201007064011.GA50074@mtl-vdi-166.wap.labs.mlnxSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

A VM with mlx5 vDPA has below warnings while being reset:

vhost VQ 0 ring restore failed: -1: Resource temporarily unavailable (11)
vhost VQ 1 ring restore failed: -1: Resource temporarily unavailable (11)

We should allow userspace emulating the virtio device be
able to get to vq's avail_index, regardless of vDPA device
status. Save the index that was last seen when virtq was
stopped, so that userspace doesn't complain.
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Link: https://lore.kernel.org/r/1601583511-15138-1-git-send-email-si-wei.liu@oracle.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eli Cohen <elic@nvidia.com>

Add usb ids of the Cellient MPL200 card.
Signed-off-by: Wilken Gottwalt <wilken.gottwalt@mailbox.org>
Acked-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

De-referencing skb after call to gro_cells_receive() is not allowed.
We need to fetch skb->len earlier.

Fixes: 5491e7c6 ("macsec: enable GRO and RPS on macsec devices")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Some firmware files trigger a PHY soft reset and don't wait for it to
be finished. PHY register writes directly after applying the firmware
may fail or provide unexpected results therefore. Fix this by waiting
for bit BMCR_RESET to be cleared after applying firmware.

There's nothing wrong with the referenced change, it's just that the
fix will apply cleanly only after this change.

Fixes: 89fbd26c ("r8169: fix firmware not resetting tp->ocp_base")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

With multiple DNAT rules it's possible that after destination
translation the resulting tuples collide.

For example, two openvswitch flows:
nw_dst=10.0.0.10,tp_dst=10, actions=ct(commit,table=2,nat(dst=20.0.0.1:20))
nw_dst=10.0.0.20,tp_dst=10, actions=ct(commit,table=2,nat(dst=20.0.0.1:20))

Assuming two TCP clients initiating the following connections:
10.0.0.10:5000->10.0.0.10:10
10.0.0.10:5000->10.0.0.20:10

Both tuples would translate to 10.0.0.10:5000->20.0.0.1:20 causing
nf_conntrack_confirm() to fail because of tuple collision.

Netfilter handles this case by allocating a null binding for SNAT at
egress by default.  Perform the same operation in openvswitch for DNAT
if no explicit SNAT is requested by the user and allocate a null binding
for SNAT for packets in the "original" direction.

Reported-at: https://bugzilla.redhat.com/1877128Suggested-by: Florian Westphal <fw@strlen.de>
Fixes: 05752523 ("openvswitch: Interface with NAT.")
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

After freeing ep->auth_hmacs we have to clear the pointer
or risk use-after-free as reported by syzbot:

BUG: KASAN: use-after-free in sctp_auth_destroy_hmacs net/sctp/auth.c:509 [inline]
BUG: KASAN: use-after-free in sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline]
BUG: KASAN: use-after-free in sctp_auth_free+0x17e/0x1d0 net/sctp/auth.c:1070
Read of size 8 at addr ffff8880a8ff52c0 by task syz-executor941/6874

CPU: 0 PID: 6874 Comm: syz-executor941 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 sctp_auth_destroy_hmacs net/sctp/auth.c:509 [inline]
 sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline]
 sctp_auth_free+0x17e/0x1d0 net/sctp/auth.c:1070
 sctp_endpoint_destroy+0x95/0x240 net/sctp/endpointola.c:203
 sctp_endpoint_put net/sctp/endpointola.c:236 [inline]
 sctp_endpoint_free+0xd6/0x110 net/sctp/endpointola.c:183
 sctp_destroy_sock+0x9c/0x3c0 net/sctp/socket.c:4981
 sctp_v6_destroy_sock+0x11/0x20 net/sctp/socket.c:9415
 sk_common_release+0x64/0x390 net/core/sock.c:3254
 sctp_close+0x4ce/0x8b0 net/sctp/socket.c:1533
 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431
 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:475
 __sock_release+0xcd/0x280 net/socket.c:596
 sock_close+0x18/0x20 net/socket.c:1277
 __fput+0x285/0x920 fs/file_table.c:281
 task_work_run+0xdd/0x190 kernel/task_work.c:141
 exit_task_work include/linux/task_work.h:25 [inline]
 do_exit+0xb7d/0x29f0 kernel/exit.c:806
 do_group_exit+0x125/0x310 kernel/exit.c:903
 __do_sys_exit_group kernel/exit.c:914 [inline]
 __se_sys_exit_group kernel/exit.c:912 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:912
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43f278
Code: Bad RIP value.
RSP: 002b:00007fffe0995c38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f278
RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
RBP: 00000000004bf068 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 6874:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 kmem_cache_alloc_trace+0x174/0x300 mm/slab.c:3554
 kmalloc include/linux/slab.h:554 [inline]
 kmalloc_array include/linux/slab.h:593 [inline]
 kcalloc include/linux/slab.h:605 [inline]
 sctp_auth_init_hmacs+0xdb/0x3b0 net/sctp/auth.c:464
 sctp_auth_init+0x8a/0x4a0 net/sctp/auth.c:1049
 sctp_setsockopt_auth_supported net/sctp/socket.c:4354 [inline]
 sctp_setsockopt+0x477e/0x97f0 net/sctp/socket.c:4631
 __sys_setsockopt+0x2db/0x610 net/socket.c:2132
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 6874:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3422 [inline]
 kfree+0x10e/0x2b0 mm/slab.c:3760
 sctp_auth_destroy_hmacs net/sctp/auth.c:511 [inline]
 sctp_auth_destroy_hmacs net/sctp/auth.c:501 [inline]
 sctp_auth_init_hmacs net/sctp/auth.c:496 [inline]
 sctp_auth_init_hmacs+0x2b7/0x3b0 net/sctp/auth.c:454
 sctp_auth_init+0x8a/0x4a0 net/sctp/auth.c:1049
 sctp_setsockopt_auth_supported net/sctp/socket.c:4354 [inline]
 sctp_setsockopt+0x477e/0x97f0 net/sctp/socket.c:4631
 __sys_setsockopt+0x2db/0x610 net/socket.c:2132
 __do_sys_setsockopt net/socket.c:2143 [inline]
 __se_sys_setsockopt net/socket.c:2140 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2140
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: 1f485649 ("[SCTP]: Implement SCTP-AUTH internals")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Merge tag 'mac80211-for-net-2020-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
pull-request: mac80211 2020-10-08

A single fix for missing input validation in nl80211.
====================
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Daniel Borkmann says:

====================
pull-request: bpf 2020-10-08

The main changes are:

1) Fix "unresolved symbol" build error under CONFIG_NET w/o CONFIG_INET due
   to missing tcp_timewait_sock and inet_timewait_sock BTF, from Yonghong Song.

2) Fix 32 bit sub-register bounds tracking for OR case, from Daniel Borkmann.
====================
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

This commit is correcting NETLINK br_fill_ifinfo() to be able to
handle 'filter_mask' with multiple flags asserted.

Fixes: 36a8e8e2 ("bridge: Extend br_fill_ifinfo to return MPR status")
Signed-off-by: Henrik Bjoernlund <henrik.bjoernlund@microchip.com>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Suggested-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull drm nouveau fixes from Dave Airlie:
 "Karol found two last minute nouveau fixes, they both fix crashes, the
  TTM one follows what other drivers do already, and the other is for
  bailing on load on unrecognised chipsets.

   - fix crash in TTM alloc fail path

   - return error earlier for unknown chipsets"

* tag 'drm-fixes-2020-10-08' of git://anongit.freedesktop.org/drm/drm:
  drm/nouveau/mem: guard against NULL pointer access in mem_del
  drm/nouveau/device: return error for unknown chipsets

Pull exfat fixes from Namjae Jeon:

 - Fix use of uninitialized spinlock on error path

 - Fix missing err assignment in exfat_build_inode()

* tag 'exfat-for-5.9-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
  exfat: fix use of uninitialized spinlock on error path
  exfat: fix pointer error checking

Pull xen fix from Juergen Gross:
 "One fix for a regression when booting as a Xen guest on ARM64
  introduced probably during the 5.9 cycle. It is very low risk as it is
  modifying Xen specific code only.

  The exact commit introducing the bug hasn't been identified yet, but
  everything was fine in 5.8 and only in 5.9 some configurations started
  to fail"

* tag 'for-linus-5.9b-rc9-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  arm/arm64: xen: Fix to convert percpu address to gfn correctly

The afs filesystem has a lock[*] that it uses to serialise I/O operations
going to the server (vnode->io_lock), as the server will only perform one
modification operation at a time on any given file or directory.  This
prevents the the filesystem from filling up all the call slots to a server
with calls that aren't going to be executed in parallel anyway, thereby
allowing operations on other files to obtain slots.

  [*] Note that is probably redundant for directories at least since
      i_rwsem is used to serialise directory modifications and
      lookup/reading vs modification.  The server does allow parallel
      non-modification ops, however.

When a file truncation op completes, we truncate the in-memory copy of the
file to match - but we do it whilst still holding the io_lock, the idea
being to prevent races with other operations.

However, if writeback starts in a worker thread simultaneously with
truncation (whilst notify_change() is called with i_rwsem locked, writeback
pays it no heed), it may manage to set PG_writeback bits on the pages that
will get truncated before afs_setattr_success() manages to call
truncate_pagecache().  Truncate will then wait for those pages - whilst
still inside io_lock:

    # cat /proc/8837/stack
    [<0>] wait_on_page_bit_common+0x184/0x1e7
    [<0>] truncate_inode_pages_range+0x37f/0x3eb
    [<0>] truncate_pagecache+0x3c/0x53
    [<0>] afs_setattr_success+0x4d/0x6e
    [<0>] afs_wait_for_operation+0xd8/0x169
    [<0>] afs_do_sync_operation+0x16/0x1f
    [<0>] afs_setattr+0x1fb/0x25d
    [<0>] notify_change+0x2cf/0x3c4
    [<0>] do_truncate+0x7f/0xb2
    [<0>] do_sys_ftruncate+0xd1/0x104
    [<0>] do_syscall_64+0x2d/0x3a
    [<0>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

The writeback operation, however, stalls indefinitely because it needs to
get the io_lock to proceed:

    # cat /proc/5940/stack
    [<0>] afs_get_io_locks+0x58/0x1ae
    [<0>] afs_begin_vnode_operation+0xc7/0xd1
    [<0>] afs_store_data+0x1b2/0x2a3
    [<0>] afs_write_back_from_locked_page+0x418/0x57c
    [<0>] afs_writepages_region+0x196/0x224
    [<0>] afs_writepages+0x74/0x156
    [<0>] do_writepages+0x2d/0x56
    [<0>] __writeback_single_inode+0x84/0x207
    [<0>] writeback_sb_inodes+0x238/0x3cf
    [<0>] __writeback_inodes_wb+0x68/0x9f
    [<0>] wb_writeback+0x145/0x26c
    [<0>] wb_do_writeback+0x16a/0x194
    [<0>] wb_workfn+0x74/0x177
    [<0>] process_one_work+0x174/0x264
    [<0>] worker_thread+0x117/0x1b9
    [<0>] kthread+0xec/0xf1
    [<0>] ret_from_fork+0x1f/0x30

and thus deadlock has occurred.

Note that whilst afs_setattr() calls filemap_write_and_wait(), the fact
that the caller is holding i_rwsem doesn't preclude more pages being
dirtied through an mmap'd region.

Fix this by:

 (1) Use the vnode validate_lock to mediate access between afs_setattr()
     and afs_writepages():

     (a) Exclusively lock validate_lock in afs_setattr() around the whole
     	 RPC operation.

     (b) If WB_SYNC_ALL isn't set on entry to afs_writepages(), trying to
     	 shared-lock validate_lock and returning immediately if we couldn't
     	 get it.

     (c) If WB_SYNC_ALL is set, wait for the lock.

     The validate_lock is also used to validate a file and to zap its cache
     if the file was altered by a third party, so it's probably a good fit
     for this.

 (2) Move the truncation outside of the io_lock in setattr, using the same
     hook as is used for local directory editing.

     This requires the old i_size to be retained in the operation record as
     we commit the revised status to the inode members inside the io_lock
     still, but we still need to know if we reduced the file size.

Fixes: d2ddc776 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit 70e806e4 ("mm: Do early cow for pinned pages during fork()
for ptes") we write-protected the PTE before doing the page pinning
check, in order to avoid a race with concurrent fast-GUP pinning (which
doesn't take the mm semaphore or the page table lock).

That trick doesn't actually work - it doesn't handle memory ordering
properly, and doing so would be prohibitively expensive.

It also isn't really needed.  While we're moving in the direction of
allowing and supporting page pinning without marking the pinned area
with MADV_DONTFORK, the fact is that we've never really supported this
kind of odd "concurrent fork() and page pinning", and doing the
serialization on a pte level is just wrong.

We can add serialization with a per-mm sequence counter, so we know how
to solve that race properly, but we'll do that at a more appropriate
time.  Right now this just removes the write protect games.

It also turns out that the write protect games actually break on Power,
as reported by Aneesh Kumar:

 "Architecture like ppc64 expects set_pte_at to be not used for updating
  a valid pte. This is further explained in commit 56eecdb9 ("mm:
  Use ptep/pmdp_set_numa() for updating _PAGE_NUMA bit")"

and the code triggered a warning there:

  WARNING: CPU: 0 PID: 30613 at arch/powerpc/mm/pgtable.c:185 set_pte_at+0x2a8/0x3a0 arch/powerpc/mm/pgtable.c:185
  Call Trace:
    copy_present_page mm/memory.c:857 [inline]
    copy_present_pte mm/memory.c:899 [inline]
    copy_pte_range mm/memory.c:1014 [inline]
    copy_pmd_range mm/memory.c:1092 [inline]
    copy_pud_range mm/memory.c:1127 [inline]
    copy_p4d_range mm/memory.c:1150 [inline]
    copy_page_range+0x1f6c/0x2cc0 mm/memory.c:1212
    dup_mmap kernel/fork.c:592 [inline]
    dup_mm+0x77c/0xab0 kernel/fork.c:1355
    copy_mm kernel/fork.c:1411 [inline]
    copy_process+0x1f00/0x2740 kernel/fork.c:2070
    _do_fork+0xc4/0x10b0 kernel/fork.c:2429

Link: https://lore.kernel.org/lkml/CAHk-=wiWr+gO0Ro4LvnJBMs90OiePNyrE3E+pJvc9PzdBShdmw@mail.gmail.com/
Link: https://lore.kernel.org/linuxppc-dev/20201008092541.398079-1-aneesh.kumar@linux.ibm.com/Reported-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Tested-by: Leon Romanovsky <leonro@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill Shutemov <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In nl80211_parse_key(), key.idx is first initialized as -1.
If this value of key.idx remains unmodified and gets returned, and
nl80211_key_allowed() also returns 0, then rdev_del_key() gets called
with key.idx = -1.
This causes an out-of-bounds array access.

Handle this issue by checking if the value of key.idx after
nl80211_parse_key() is called and return -EINVAL if key.idx < 0.

Cc: stable@vger.kernel.org
Reported-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com
Tested-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com
Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
Link: https://lore.kernel.org/r/20201007035401.9522-1-anant.thazhemadam@gmail.comSigned-off-by: Johannes Berg <johannes.berg@intel.com>

Simon reported an issue with the current scalar32_min_max_or() implementation.
That is, compared to the other 32 bit subreg tracking functions, the code in
scalar32_min_max_or() stands out that it's using the 64 bit registers instead
of 32 bit ones. This leads to bounds tracking issues, for example:

  [...]
  8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  8: (79) r1 = *(u64 *)(r0 +0)
   R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  9: (b7) r0 = 1
  10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  10: (18) r2 = 0x600000002
  12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  12: (ad) if r1 < r2 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: (95) exit
  14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  14: (25) if r1 > 0x0 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: (95) exit
  16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  16: (47) r1 |= 0
  17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x1; 0x700000000),s32_max_value=1,u32_max_value=1) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  [...]

The bound tests on the map value force the upper unsigned bound to be 25769803777
in 64 bit (0b11000000000000000000000000000000001) and then lower one to be 1. By
using OR they are truncated and thus result in the range [1,1] for the 32 bit reg
tracker. This is incorrect given the only thing we know is that the value must be
positive and thus 2147483647 (0b1111111111111111111111111111111) at max for the
subregs. Fix it by using the {u,s}32_{min,max}_value vars instead. This also makes
sense, for example, for the case where we update dst_reg->s32_{min,max}_value in
the else branch we need to use the newly computed dst_reg->u32_{min,max}_value as
we know that these are positive. Previously, in the else branch the 64 bit values
of umin_value=1 and umax_value=32212254719 were used and latter got truncated to
be 1 as upper bound there. After the fix the subreg range is now correct:

  [...]
  8: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  8: (79) r1 = *(u64 *)(r0 +0)
   R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R10=fp0 fp-8=mmmmmmmm
  9: R0=map_value(id=0,off=0,ks=4,vs=48,imm=0) R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  9: (b7) r0 = 1
  10: R0_w=inv1 R1_w=inv(id=0) R10=fp0 fp-8=mmmmmmmm
  10: (18) r2 = 0x600000002
  12: R0_w=inv1 R1_w=inv(id=0) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  12: (ad) if r1 < r2 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: R0_w=inv1 R1_w=inv(id=0,umin_value=25769803778) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  13: (95) exit
  14: R0_w=inv1 R1_w=inv(id=0,umax_value=25769803777,var_off=(0x0; 0x7ffffffff)) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  14: (25) if r1 > 0x0 goto pc+1
   R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: R0_w=inv1 R1_w=inv(id=0,umax_value=0,var_off=(0x0; 0x7fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  15: (95) exit
  16: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=25769803777,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  16: (47) r1 |= 0
  17: R0_w=inv1 R1_w=inv(id=0,umin_value=1,umax_value=32212254719,var_off=(0x0; 0x77fffffff),u32_max_value=2147483647) R2_w=inv25769803778 R10=fp0 fp-8=mmmmmmmm
  [...]

Fixes: 3f50f132 ("bpf: Verifier, do explicit ALU32 bounds tracking")
Reported-by: Simon Scannell <scannell.smn@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>

other drivers seems to do something similar
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201006220528.13925-2-kherbst@redhat.com

Previously the code relied on device->pri to be NULL and to fail probing
later. We really should just return an error inside nvkm_device_ctor for
unsupported GPUs.

Fixes: 24d5ff40 ("drm/nouveau/device: rework mmio mapping code to get rid of second map")
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Cc: dann frazier <dann.frazier@canonical.com>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Cc: Dave Airlie <airlied@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201006220528.13925-1-kherbst@redhat.com

syzbot reported warning message:

Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d6/0x29e lib/dump_stack.c:118
 register_lock_class+0xf06/0x1520 kernel/locking/lockdep.c:893
 __lock_acquire+0xfd/0x2ae0 kernel/locking/lockdep.c:4320
 lock_acquire+0x148/0x720 kernel/locking/lockdep.c:5029
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 exfat_cache_inval_inode+0x30/0x280 fs/exfat/cache.c:226
 exfat_evict_inode+0x124/0x270 fs/exfat/inode.c:660
 evict+0x2bb/0x6d0 fs/inode.c:576
 exfat_fill_super+0x1e07/0x27d0 fs/exfat/super.c:681
 get_tree_bdev+0x3e9/0x5f0 fs/super.c:1342
 vfs_get_tree+0x88/0x270 fs/super.c:1547
 do_new_mount fs/namespace.c:2875 [inline]
 path_mount+0x179d/0x29e0 fs/namespace.c:3192
 do_mount fs/namespace.c:3205 [inline]
 __do_sys_mount fs/namespace.c:3413 [inline]
 __se_sys_mount+0x126/0x180 fs/namespace.c:3390
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

If exfat_read_root() returns an error, spinlock is used in
exfat_evict_inode() without initialization. This patch combines
exfat_cache_init_inode() with exfat_inode_init_once() to initialize
spinlock by slab constructor.

Fixes: c35b6810 ("exfat: add exfat cache")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: syzbot <syzbot+b91107320911a26c9a95@syzkaller.appspotmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

Fix missing result check of exfat_build_inode().
And use PTR_ERR_OR_ZERO instead of PTR_ERR.
Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

Use per_cpu_ptr_to_phys() instead of virt_to_phys() for per-cpu
address conversion.

In xen_starting_cpu(), per-cpu xen_vcpu_info address is converted
to gfn by virt_to_gfn() macro. However, since the virt_to_gfn(v)
assumes the given virtual address is in linear mapped kernel memory
area, it can not convert the per-cpu memory if it is allocated on
vmalloc area.

This depends on CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK.
If it is enabled, the first chunk of percpu memory is linear mapped.
In the other case, that is allocated from vmalloc area. Moreover,
if the first chunk of percpu has run out until allocating
xen_vcpu_info, it will be allocated on the 2nd chunk, which is
based on kernel memory or vmalloc memory (depends on
CONFIG_NEED_PER_CPU_KM).

Without this fix and kernel configured to use vmalloc area for
the percpu memory, the Dom0 kernel will fail to boot with following
errors.

[    0.466172] Xen: initializing cpu0
[    0.469601] ------------[ cut here ]------------
[    0.474295] WARNING: CPU: 0 PID: 1 at arch/arm64/xen/../../arm/xen/enlighten.c:153 xen_starting_cpu+0x160/0x180
[    0.484435] Modules linked in:
[    0.487565] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc4+ #4
[    0.493895] Hardware name: Socionext Developer Box (DT)
[    0.499194] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--)
[    0.504836] pc : xen_starting_cpu+0x160/0x180
[    0.509263] lr : xen_starting_cpu+0xb0/0x180
[    0.513599] sp : ffff8000116cbb60
[    0.516984] x29: ffff8000116cbb60 x28: ffff80000abec000
[    0.522366] x27: 0000000000000000 x26: 0000000000000000
[    0.527754] x25: ffff80001156c000 x24: fffffdffbfcdb600
[    0.533129] x23: 0000000000000000 x22: 0000000000000000
[    0.538511] x21: ffff8000113a99c8 x20: ffff800010fe4f68
[    0.543892] x19: ffff8000113a9988 x18: 0000000000000010
[    0.549274] x17: 0000000094fe0f81 x16: 00000000deadbeef
[    0.554655] x15: ffffffffffffffff x14: 0720072007200720
[    0.560037] x13: 0720072007200720 x12: 0720072007200720
[    0.565418] x11: 0720072007200720 x10: 0720072007200720
[    0.570801] x9 : ffff8000100fbdc0 x8 : ffff800010715208
[    0.576182] x7 : 0000000000000054 x6 : ffff00001b790f00
[    0.581564] x5 : ffff800010bbf880 x4 : 0000000000000000
[    0.586945] x3 : 0000000000000000 x2 : ffff80000abec000
[    0.592327] x1 : 000000000000002f x0 : 0000800000000000
[    0.597716] Call trace:
[    0.600232]  xen_starting_cpu+0x160/0x180
[    0.604309]  cpuhp_invoke_callback+0xac/0x640
[    0.608736]  cpuhp_issue_call+0xf4/0x150
[    0.612728]  __cpuhp_setup_state_cpuslocked+0x128/0x2c8
[    0.618030]  __cpuhp_setup_state+0x84/0xf8
[    0.622192]  xen_guest_init+0x324/0x364
[    0.626097]  do_one_initcall+0x54/0x250
[    0.630003]  kernel_init_freeable+0x12c/0x2c8
[    0.634428]  kernel_init+0x1c/0x128
[    0.637988]  ret_from_fork+0x10/0x18
[    0.641635] ---[ end trace d95b5309a33f8b27 ]---
[    0.646337] ------------[ cut here ]------------
[    0.651005] kernel BUG at arch/arm64/xen/../../arm/xen/enlighten.c:158!
[    0.657697] Internal error: Oops - BUG: 0 [#1] SMP
[    0.662548] Modules linked in:
[    0.665676] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G        W         5.9.0-rc4+ #4
[    0.673398] Hardware name: Socionext Developer Box (DT)
[    0.678695] pstate: 00000005 (nzcv daif -PAN -UAO BTYPE=--)
[    0.684338] pc : xen_starting_cpu+0x178/0x180
[    0.688765] lr : xen_starting_cpu+0x144/0x180
[    0.693188] sp : ffff8000116cbb60
[    0.696573] x29: ffff8000116cbb60 x28: ffff80000abec000
[    0.701955] x27: 0000000000000000 x26: 0000000000000000
[    0.707344] x25: ffff80001156c000 x24: fffffdffbfcdb600
[    0.712718] x23: 0000000000000000 x22: 0000000000000000
[    0.718107] x21: ffff8000113a99c8 x20: ffff800010fe4f68
[    0.723481] x19: ffff8000113a9988 x18: 0000000000000010
[    0.728863] x17: 0000000094fe0f81 x16: 00000000deadbeef
[    0.734245] x15: ffffffffffffffff x14: 0720072007200720
[    0.739626] x13: 0720072007200720 x12: 0720072007200720
[    0.745008] x11: 0720072007200720 x10: 0720072007200720
[    0.750390] x9 : ffff8000100fbdc0 x8 : ffff800010715208
[    0.755771] x7 : 0000000000000054 x6 : ffff00001b790f00
[    0.761153] x5 : ffff800010bbf880 x4 : 0000000000000000
[    0.766534] x3 : 0000000000000000 x2 : 00000000deadbeef
[    0.771916] x1 : 00000000deadbeef x0 : ffffffffffffffea
[    0.777304] Call trace:
[    0.779819]  xen_starting_cpu+0x178/0x180
[    0.783898]  cpuhp_invoke_callback+0xac/0x640
[    0.788325]  cpuhp_issue_call+0xf4/0x150
[    0.792317]  __cpuhp_setup_state_cpuslocked+0x128/0x2c8
[    0.797619]  __cpuhp_setup_state+0x84/0xf8
[    0.801779]  xen_guest_init+0x324/0x364
[    0.805683]  do_one_initcall+0x54/0x250
[    0.809590]  kernel_init_freeable+0x12c/0x2c8
[    0.814016]  kernel_init+0x1c/0x128
[    0.817583]  ret_from_fork+0x10/0x18
[    0.821226] Code: d0006980 f9427c00 cb000300 17ffffea (d4210000)
[    0.827415] ---[ end trace d95b5309a33f8b28 ]---
[    0.832076] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[    0.839815] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/160196697165.60224.17470743378683334995.stgit@devnote2Signed-off-by: Juergen Gross <jgross@suse.com>

Pull arm64 fix from Catalin Marinas:
 "Fix a kernel panic in the AES crypto code caused by a BR tail call not
  matching the target BTI instruction (when branch target identification
  is enabled)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  crypto: arm64: Use x16 with indirect branch to bti_c

Merge tag 'platform-drivers-x86-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull another x86 platform driver fix from Hans de Goede:
 "One final pdx86 fix for Tablet Mode reporting regressions (which make
  the keyboard and touchpad unusable) on various Asus notebooks.

  These regressions were caused by the asus-nb-wmi and the intel-vbtn
  drivers both receiving recent patches to start reporting Tablet Mode /
  to report it on more models.

  Due to a miscommunication between Andy and me, Andy's earlier pull-req
  only contained the fix for the intel-vbtn driver and not the fix for
  the asus-nb-wmi code.

  This fix has been tested as a downstream patch in Fedora kernels for
  approx two weeks with no problems being reported"

* tag 'platform-drivers-x86-v5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: asus-wmi: Fix SW_TABLET_MODE always reporting 1 on many different models

Pull drm fixes from Dave Airlie:
 "Daniel queued these up last week and I took a long weekend so didn't
  get them out, but fixing the OOB access on get font seems like
  something we should land and it's cc'ed stable as well.

  The other big change is a partial revert for a regression on android
  on the clcd fbdev driver, and one other docs fix.

  fbdev:
   - Re-add FB_ARMCLCD for android
   - Fix global-out-of-bounds read in fbcon_get_font()

  core:
   - Small doc fix"

* tag 'drm-fixes-2020-10-06-1' of git://anongit.freedesktop.org/drm/drm:
  drm: drm_dsc.h: fix a kernel-doc markup
  Partially revert "video: fbdev: amba-clcd: Retire elder CLCD driver"
  fbcon: Fix global-out-of-bounds read in fbcon_get_font()
  Fonts: Support FONT_EXTRA_WORDS macros for built-in fonts
  fbdev, newport_con: Move FONT_EXTRA_WORDS macros into linux/font.h

Kernel threads intentionally do CLONE_FS in order to follow any changes
that 'init' does to set up the root directory (or cwd).

It is admittedly a bit odd, but it avoids the situation where 'init'
does some extensive setup to initialize the system environment, and then
we execute a usermode helper program, and it uses the original FS setup
from boot time that may be very limited and incomplete.

[ Both Al Viro and Eric Biederman point out that 'pivot_root()' will
  follow the root regardless, since it fixes up other users of root (see
  chroot_fs_refs() for details), but overmounting root and doing a
  chroot() would not. ]

However, Vegard Nossum noticed that the CLONE_FS not only means that we
follow the root and current working directories, it also means we share
umask with whatever init changed it to. That wasn't intentional.

Just reset umask to the original default (0022) before actually starting
the usermode helper program.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Tetsuo Handa reports that splice() can return 0 before the real EOF, if
the data in the splice source pipe is an empty pipe buffer.  That empty
pipe buffer case doesn't happen in any normal situation, but you can
trigger it by doing a write to a pipe that fails due to a page fault.

Tetsuo has a test-case to show the behavior:

  #define _GNU_SOURCE
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  #include <unistd.h>

  int main(int argc, char *argv[])
  {
	const int fd = open("/tmp/testfile", O_WRONLY | O_CREAT, 0600);
	int pipe_fd[2] = { -1, -1 };
	pipe(pipe_fd);
	write(pipe_fd[1], NULL, 4096);
	/* This splice() should wait unless interrupted. */
	return !splice(pipe_fd[0], NULL, fd, NULL, 65536, 0);
  }

which results in

    write(5, NULL, 4096)                    = -1 EFAULT (Bad address)
    splice(4, NULL, 3, NULL, 65536, 0)      = 0

and this can confuse splice() users into believing they have hit EOF
prematurely.

The issue was introduced when the pipe write code started pre-allocating
the pipe buffers before copying data from user space.

This is modified verion of Tetsuo's original patch.

Fixes: a194dfe6 ("pipe: Rearrange sequence in pipe_write() to preallocate slot")
Link:https://lore.kernel.org/linux-fsdevel/20201005121339.4063-1-penguin-kernel@I-love.SAKURA.ne.jp/Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Acked-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The AES code uses a 'br x7' as part of a function called by
a macro. That branch needs a bti_j as a target. This results
in a panic as seen below. Using x16 (or x17) with an indirect
branch keeps the target bti_c.

  Bad mode in Synchronous Abort handler detected on CPU1, code 0x34000003 -- BTI
  CPU: 1 PID: 265 Comm: cryptomgr_test Not tainted 5.8.11-300.fc33.aarch64 #1
  pstate: 20400c05 (nzCv daif +PAN -UAO BTYPE=j-)
  pc : aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs]
  lr : aesbs_xts_encrypt+0x48/0xe0 [aes_neon_bs]
  sp : ffff80001052b730

  aesbs_encrypt8+0x0/0x5f0 [aes_neon_bs]
   __xts_crypt+0xb0/0x2dc [aes_neon_bs]
   xts_encrypt+0x28/0x3c [aes_neon_bs]
  crypto_skcipher_encrypt+0x50/0x84
  simd_skcipher_encrypt+0xc8/0xe0
  crypto_skcipher_encrypt+0x50/0x84
  test_skcipher_vec_cfg+0x224/0x5f0
  test_skcipher+0xbc/0x120
  alg_test_skcipher+0xa0/0x1b0
  alg_test+0x3dc/0x47c
  cryptomgr_test+0x38/0x60

Fixes: 0e89640b ("crypto: arm64 - Use modern annotations for assembly functions")
Cc: <stable@vger.kernel.org> # 5.6.x-
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Suggested-by: Dave P Martin <Dave.Martin@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20201006163326.2780619-1-jeremy.linton@arm.comSigned-off-by: Catalin Marinas <catalin.marinas@arm.com>

Jakub Kicinski says:

====================
ethtool: allow dumping policies to user space

This series wires up ethtool policies to ops, so they can be
dumped to user space for feature discovery.

First patch wires up GET commands, and second patch wires up SETs.

The policy tables are trimmed to save space and LoC.

Next - take care of linking up nested policies for the header
(which is the policy what we actually care about). And once header
policy is linked make sure that attribute range validation for flags
is done by policy, not a conditions in the code. New type of policy
is needed to validate masks (patch 6).

Netlink as always staying a step ahead of all the other kernel
API interfaces :)

v2:
 - merge patches 1 & 2 -> 1
 - add patch 3 & 5
 - remove .max_attr from struct ethnl_request_ops
====================
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

Perform header flags validation through the policy.

Only pause command supports ETHTOOL_FLAG_STATS. Create a separate
policy to be able to express that in policy dumps to user space.

Note that even though the core will validate the header policy,
it cannot record multiple layers of attributes and we have to
re-parse header sub-attrs. When doing so we could skip attribute
validation, or use most permissive policy. Opt for the former.

We will no longer return the extack cookie for flags but since
we only added first new flag in this release it's not expected
that any user space had a chance to make use of it.

v2: - remove the re-validation in ethnl_parse_header_dev_get()
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>