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  1. 10 Oct, 2020 2 commits
    • Hugh Dickins's avatar
      mm/khugepaged: fix filemap page_to_pgoff(page) != offset · 033b5d77
      Hugh Dickins authored 
      There have been elusive reports of filemap_fault() hitting its
VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page) on kernels built
with CONFIG_READ_ONLY_THP_FOR_FS=y.

Suren has hit it on a kernel with CONFIG_READ_ONLY_THP_FOR_FS=y and
CONFIG_NUMA is not set: and he has analyzed it down to how khugepaged
without NUMA reuses the same huge page after collapse_file() failed
(whereas NUMA targets its allocation to the respective node each time).
And most of us were usually testing with CONFIG_NUMA=y kernels.

collapse_file(old start)
  new_page = khugepaged_alloc_page(hpage)
  __SetPageLocked(new_page)
  new_page->index = start // hpage->index=old offset
  new_page->mapping = mapping
  xas_store(&xas, new_page)

                          filemap_fault
                            page = find_get_page(mapping, offset)
                            // if offset falls inside hpage then
                            // compound_head(page) == hpage
                            lock_page_maybe_drop_mmap()
                              __lock_page(page)

  // collapse fails
  xas_store(&xas, old page)
  new_page->mapping = NULL
  unlock_page(new_page)

collapse_file(new start)
  new_page = khugepaged_alloc_page(hpage)
  __SetPageLocked(new_page)
  new_page->index = start // hpage->index=new offset
  new_page->mapping = mapping // mapping becomes valid again

                            // since compound_head(page) == hpage
                            // page_to_pgoff(page) got changed
                            VM_BUG_ON_PAGE(page_to_pgoff(page) != offset)

An initial patch replaced __SetPageLocked() by lock_page(), which did
fix the race which Suren illustrates above.  But testing showed that it's
not good enough: if the racing task's __lock_page() gets delayed long
after its find_get_page(), then it may follow collapse_file(new start)'s
successful final unlock_page(), and crash on the same VM_BUG_ON_PAGE.

It could be fixed by relaxing filemap_fault()'s VM_BUG_ON_PAGE to a
check and retry (as is done for mapping), with similar relaxations in
find_lock_entry() and pagecache_get_page(): but it's not obvious what
else might get caught out; and khugepaged non-NUMA appears to be unique
in exposing a page to page cache, then revoking, without going through
a full cycle of freeing before reuse.

Instead, non-NUMA khugepaged_prealloc_page() release the old page
if anyone else has a reference to it (1% of cases when I tested).

Although never reported on huge tmpfs, I believe its find_lock_entry()
has been at similar risk; but huge tmpfs does not rely on khugepaged
for its normal working nearly so much as READ_ONLY_THP_FOR_FS does.
Reported-by: default avatarDenis Lisov <dennis.lissov@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206569
Link: https://lore.kernel.org/linux-mm/?q=20200219144635.3b7417145de19b65f258c943%40linux-foundation.orgReported-by: default avatarQian Cai <cai@lca.pw>
Link: https://lore.kernel.org/linux-xfs/?q=20200616013309.GB815%40lca.pwReported-and-analyzed-by: default avatarSuren Baghdasaryan <surenb@google.com>
Fixes: 87c460a0 ("mm/khugepaged: collapse_shmem() without freezing new_page")
Signed-off-by: default avatarHugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v4.9+
Reviewed-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      033b5d77
    • Linus Torvalds's avatar
      Merge tag 'spi-fix-v5.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi · 6f2f486d
      Linus Torvalds authored 
      Pull spi fix from Mark Brown:
 "One last minute fix for v5.9 which has been causing crashes in test
  systems with the fsl-dspi driver when they hit deferred probe (and
  which I probably let cook in next a bit longer than is ideal).

  And an update to MAINTAINERS reflecting Serge's extensive and
  detailed recent work on the DesignWare driver"

* tag 'spi-fix-v5.9-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  MAINTAINERS: Add maintainer of DW APB SSI driver
  spi: fsl-dspi: fix NULL pointer dereference
      6f2f486d
  3. 09 Oct, 2020 8 commits
  5. 08 Oct, 2020 21 commits
    • Sebastian Reichel's avatar
      power: supply: sbs-battery: chromebook workaround for PEC · e3f2396b
      Sebastian Reichel authored 
      Looks like the I2C tunnel implementation from Chromebook's
embedded controller does not handle PEC correctly. Fix this
by disabling PEC for batteries behind those I2C tunnels as
a workaround.

Note, that some Chromebooks actually have been reported to
have working PEC support (with I2C tunnel). Since the problem
has not yet been fully understood this simply reverts all
Chromebooks to not use PEC for now.
Reported-by: default avatar"Milan P. Stanić" <mps@arvanta.net>
Reported-by: default avatarVicente Bergas <vicencb@gmail.com>
CC: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Fixes: 7222bd60 ("power: supply: sbs-battery: add PEC support")
Tested-by: default avatarVicente Bergas <vicencb@gmail.com>
Tested-by: default avatar"Milan P. Stanić" <mps@arvanta.net>
Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
      e3f2396b
    • Linus Torvalds's avatar
      Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost · 3fdd47c3
      Linus Torvalds authored 
      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
      3fdd47c3
    • Yongqiang Sun's avatar
      drm/amd/display: Change ABM config init interface · 33c8256b
      Yongqiang Sun authored 
      [Why & How]
change abm config init interface to support multiple ABMs.
Signed-off-by: default avatarYongqiang Sun <yongqiang.sun@amd.com>
Reviewed-by: default avatarChris Park <Chris.Park@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
      33c8256b
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net · 6288c1d8
      Linus Torvalds authored 
      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
  ...
      6288c1d8
    • Eli Cohen's avatar
      vdpa/mlx5: Fix dependency on MLX5_CORE · aff90770
      Eli Cohen authored 
      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: default avatarkernel test robot <lkp@intel.com>
Fixes: 1a86b377 ("vdpa/mlx5: Add VDPA driver for supported mlx5 device")s
Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20201007064011.GA50074@mtl-vdi-166.wap.labs.mlnxSigned-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      aff90770
    • Si-Wei Liu's avatar
      vdpa/mlx5: should keep avail_index despite device status · 3176e974
      Si-Wei Liu authored 
      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: default avatarSi-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: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarEli Cohen <elic@nvidia.com>
      3176e974
    • Wilken Gottwalt's avatar
      net: usb: qmi_wwan: add Cellient MPL200 card · 28802e7c
      Wilken Gottwalt authored 
      Add usb ids of the Cellient MPL200 card.
Signed-off-by: default avatarWilken Gottwalt <wilken.gottwalt@mailbox.org>
Acked-by: default avatarBjørn Mork <bjorn@mork.no>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      28802e7c
    • Eric Dumazet's avatar
      macsec: avoid use-after-free in macsec_handle_frame() · c7cc9200
      Eric Dumazet authored 
      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: default avatarEric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      c7cc9200
    • Heiner Kallweit's avatar
      r8169: consider that PHY reset may still be in progress after applying firmware · 47dda786
      Heiner Kallweit authored 
      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: default avatarHeiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      47dda786
    • Dumitru Ceara's avatar
      openvswitch: handle DNAT tuple collision · 8aa7b526
      Dumitru Ceara authored 
      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: default avatarFlorian Westphal <fw@strlen.de>
Fixes: 05752523 ("openvswitch: Interface with NAT.")
Signed-off-by: default avatarDumitru Ceara <dceara@redhat.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      8aa7b526
    • Eric Dumazet's avatar
      sctp: fix sctp_auth_init_hmacs() error path · d42ee76e
      Eric Dumazet authored 
      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: default avatarEric 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: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      d42ee76e
    • Jakub Kicinski's avatar
      Merge tag 'mac80211-for-net-2020-10-08' of... · a9e54cb3
      Jakub Kicinski authored 
      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: default avatarJakub Kicinski <kuba@kernel.org>
      a9e54cb3
    • Jakub Kicinski's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf · cfe90f49
      Jakub Kicinski authored 
      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: default avatarJakub Kicinski <kuba@kernel.org>
      cfe90f49
    • Henrik Bjoernlund's avatar
      bridge: Netlink interface fix. · b6c02ef5
      Henrik Bjoernlund authored 
      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: default avatarHenrik Bjoernlund <henrik.bjoernlund@microchip.com>
Reviewed-by: default avatarHoratiu Vultur <horatiu.vultur@microchip.com>
Suggested-by: default avatarNikolay Aleksandrov <nikolay@nvidia.com>
Tested-by: default avatarHoratiu Vultur <horatiu.vultur@microchip.com>
Acked-by: default avatarNikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
      b6c02ef5
    • Linus Torvalds's avatar
      Merge tag 'drm-fixes-2020-10-08' of git://anongit.freedesktop.org/drm/drm · 3d006ee4
      Linus Torvalds authored 
      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
      3d006ee4
    • Linus Torvalds's avatar
      Merge tag 'exfat-for-5.9-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat · b9e3aa2a
      Linus Torvalds authored 
      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
      b9e3aa2a
    • Linus Torvalds's avatar
      Merge tag 'for-linus-5.9b-rc9-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip · 86f0a5fb
      Linus Torvalds authored 
      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
      86f0a5fb
    • David Howells's avatar
      afs: Fix deadlock between writeback and truncate · ec0fa0b6
      David Howells authored 
      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: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ec0fa0b6
    • Linus Torvalds's avatar
      mm: avoid early COW write protect games during fork() · f3c64eda
      Linus Torvalds authored 
      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: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Tested-by: default avatarLeon 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: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f3c64eda
    • Anant Thazhemadam's avatar
      net: wireless: nl80211: fix out-of-bounds access in nl80211_del_key() · 3dc289f8
      Anant Thazhemadam authored 
      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: default avatarAnant Thazhemadam <anant.thazhemadam@gmail.com>
Link: https://lore.kernel.org/r/20201007035401.9522-1-anant.thazhemadam@gmail.comSigned-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
      3dc289f8
    • Daniel Borkmann's avatar
      bpf: Fix scalar32_min_max_or bounds tracking · 5b9fbeb7
      Daniel Borkmann authored 
      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: default avatarSimon Scannell <scannell.smn@gmail.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
      5b9fbeb7
  7. 07 Oct, 2020 9 commits
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