Commit graph

63517 commits

Author SHA1 Message Date
Linus Torvalds
6cad420cc6 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "A large amount of MM, plenty more to come.

  Subsystems affected by this patch series:
   - tools
   - kthread
   - kbuild
   - scripts
   - ocfs2
   - vfs
   - mm: slub, kmemleak, pagecache, gup, swap, memcg, pagemap, mremap,
         sparsemem, kasan, pagealloc, vmscan, compaction, mempolicy,
         hugetlbfs, hugetlb"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits)
  include/linux/huge_mm.h: check PageTail in hpage_nr_pages even when !THP
  mm/hugetlb: fix build failure with HUGETLB_PAGE but not HUGEBTLBFS
  selftests/vm: fix map_hugetlb length used for testing read and write
  mm/hugetlb: remove unnecessary memory fetch in PageHeadHuge()
  mm/hugetlb.c: clean code by removing unnecessary initialization
  hugetlb_cgroup: add hugetlb_cgroup reservation docs
  hugetlb_cgroup: add hugetlb_cgroup reservation tests
  hugetlb: support file_region coalescing again
  hugetlb_cgroup: support noreserve mappings
  hugetlb_cgroup: add accounting for shared mappings
  hugetlb: disable region_add file_region coalescing
  hugetlb_cgroup: add reservation accounting for private mappings
  mm/hugetlb_cgroup: fix hugetlb_cgroup migration
  hugetlb_cgroup: add interface for charge/uncharge hugetlb reservations
  hugetlb_cgroup: add hugetlb_cgroup reservation counter
  hugetlbfs: Use i_mmap_rwsem to address page fault/truncate race
  hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
  mm/memblock.c: remove redundant assignment to variable max_addr
  mm: mempolicy: require at least one nodeid for MPOL_PREFERRED
  mm: mempolicy: use VM_BUG_ON_VMA in queue_pages_test_walk()
  ...
2020-04-02 13:55:34 -07:00
Linus Torvalds
7be97138e7 New code for 5.7:
- Fix a hard to trigger race between iclog error checking and log shutdown.
  - Strengthen the AGF verifier.
  - Ratelimit some of the more spammy error messages.
  - Remove the icdinode uid/gid members and just use the ones in the vfs inode.
  - Hold ILOCK across insert/collapse range.
  - Clean up the extended attribute interfaces.
  - Clean up the attr flags mess.
  - Restore PF_MEMALLOC after exiting xfsaild thread to avoid triggering
    warnings in the process accounting code.
  - Remove the flexibly-sized array from struct xfs_agfl to eliminate
    compiler warnings about unaligned pointers and packed structures.
  - Various macro and typedef removals.
  - Stale metadata buffers if we decide they're corrupt outside of a
    verifier.
  - Check directory data/block/free block owners.
  - Fix a UAF when aborting inactivation of a corrupt xattr fork.
  - Teach online scrub to report failed directory and attr name lookups
    as a metadata corruption instead of a runtime error.
  - Avoid potential buffer overflows in sysfs files by using scnprintf.
  - Fix a regression in getdents lookups due to a mistake in pointer
    arithmetic.
  - Refactor btree cursor private data structures to use anonymous
    unions.
  - Cleanups in the log unmounting code.
  - Fix a potential mishandling of ENOMEM errors on multi-block directory
    buffer lookups.
  - Fix an incorrect test in the block allocation code.
  - Cleanups and name prefix shortening in the scrub code.
  - Introduce btree bulk loading code for online repair and scrub.
  - Fix a quotaoff log item leak (and hang) when the fs goes down midway
    through a quotaoff operation.
  - Remove di_version from the incore inode.
  - Refactor some of the log shutdown checking code.
  - Record the forcing of the log unmount records in the log force
    counters.
  - Fix a longstanding bug where quotacheck would purge the
    administrator's default quota grace interval and warning limits.
  - Reduce memory usage when scrubbing directory and xattr trees.
  - Don't let fsfreeze race with GETFSMAP or online scrub.
  - Handle bio_add_page failures more gracefully in xlog_write_iclog.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAl58z3AACgkQ+H93GTRK
 tOukrRAAhJmowV5+Req5YMYawRjafkIbCDH3WlFy9AdpFFA6pXSfX6YCtIKwKfq8
 +yRj/BFRGoMc6SouXo+J0i3YMS6yQZTjcmVWrQPVnj/+DGVjh+Y70gKExtz2CyjO
 ItGGxpRwOhpw49zVYmcH6Mrw8sBztHR0VsM0cq6YfJrkNcm0BsnAC+W6zQNaDG24
 UO1ivehBOooVh0C8pv0smVcPtBL2N+RRyS3XRT5hGFozUJgLLGDqnHAl1d+KOrWp
 hPQhUlDw9luiHPBxWkxUuFDr79gjUi7kyHILNt7TIkByyRcTUO9jhS2VpZd4oXlj
 /J3i1AS+9lhP1yGVxw2RHQhKMvdYBQiLADSCpzkA1dMma99cFGyzMMA6rG0WRMJ4
 erXxhAEoM4um3gxDka6+HJxySLOT8E22FesJbn6YIv4QSAkXDBPWz/9hPbjJuJQm
 6Y/YkFOZLp3c+xJM0tpCWxWaWW7A+t2OMRIFISSsXesrySpalpbkVXkHwz3NwO6L
 3SeTnLWqnADbjl2qsuyF0uYHqURygVz7g+r4X7AO5D1IRyCCkmtDOuwumxERiQ3p
 3vZMQrWh+y3SgRiF8brDG5KTshhxcinKdHEYXrwq3XgaHZg4mtLI4XjOyZlJruoX
 MGWhZjga6+RGysH0RKjZbHaMr/f4m3X00SHa/5Ibcp6Q21TIx6M=
 =8iJB
 -----END PGP SIGNATURE-----

Merge tag 'xfs-5.7-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs updates from Darrick Wong:
 "There's a lot going on this cycle with cleanups in the log code, the
  btree code, and the xattr code.

  We're tightening of metadata validation and online fsck checking, and
  introducing a common btree rebuilding library so that we can refactor
  xfs_repair and introduce online repair in a future cycle.

  We also fixed a few visible bugs -- most notably there's one in
  getdents that we introduced in 5.6; and a fix for hangs when disabling
  quotas.

  This series has been running fstests & other QA in the background for
  over a week and looks good so far.

  I anticipate sending a second pull request next week. That batch will
  change how xfs interacts with memory reclaim; how the log batches and
  throttles log items; how hard writes near ENOSPC will try to squeeze
  more space out of the filesystem; and hopefully fix the last of the
  umount hangs after a catastrophic failure. That should ease a lot of
  problems when running at the limits, but for now I'm leaving that in
  for-next for another week to make sure we got all the subtleties
  right.

  Summary:

   - Fix a hard to trigger race between iclog error checking and log
     shutdown.

   - Strengthen the AGF verifier.

   - Ratelimit some of the more spammy error messages.

   - Remove the icdinode uid/gid members and just use the ones in the
     vfs inode.

   - Hold ILOCK across insert/collapse range.

   - Clean up the extended attribute interfaces.

   - Clean up the attr flags mess.

   - Restore PF_MEMALLOC after exiting xfsaild thread to avoid
     triggering warnings in the process accounting code.

   - Remove the flexibly-sized array from struct xfs_agfl to eliminate
     compiler warnings about unaligned pointers and packed structures.

   - Various macro and typedef removals.

   - Stale metadata buffers if we decide they're corrupt outside of a
     verifier.

   - Check directory data/block/free block owners.

   - Fix a UAF when aborting inactivation of a corrupt xattr fork.

   - Teach online scrub to report failed directory and attr name lookups
     as a metadata corruption instead of a runtime error.

   - Avoid potential buffer overflows in sysfs files by using scnprintf.

   - Fix a regression in getdents lookups due to a mistake in pointer
     arithmetic.

   - Refactor btree cursor private data structures to use anonymous
     unions.

   - Cleanups in the log unmounting code.

   - Fix a potential mishandling of ENOMEM errors on multi-block
     directory buffer lookups.

   - Fix an incorrect test in the block allocation code.

   - Cleanups and name prefix shortening in the scrub code.

   - Introduce btree bulk loading code for online repair and scrub.

   - Fix a quotaoff log item leak (and hang) when the fs goes down
     midway through a quotaoff operation.

   - Remove di_version from the incore inode.

   - Refactor some of the log shutdown checking code.

   - Record the forcing of the log unmount records in the log force
     counters.

   - Fix a longstanding bug where quotacheck would purge the
     administrator's default quota grace interval and warning limits.

   - Reduce memory usage when scrubbing directory and xattr trees.

   - Don't let fsfreeze race with GETFSMAP or online scrub.

   - Handle bio_add_page failures more gracefully in xlog_write_iclog"

* tag 'xfs-5.7-merge-8' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (108 commits)
  xfs: prohibit fs freezing when using empty transactions
  xfs: shutdown on failure to add page to log bio
  xfs: directory bestfree check should release buffers
  xfs: drop all altpath buffers at the end of the sibling check
  xfs: preserve default grace interval during quotacheck
  xfs: remove xlog_state_want_sync
  xfs: move the ioerror check out of xlog_state_clean_iclog
  xfs: refactor xlog_state_clean_iclog
  xfs: remove the aborted parameter to xlog_state_done_syncing
  xfs: simplify log shutdown checking in xfs_log_release_iclog
  xfs: simplify the xfs_log_release_iclog calling convention
  xfs: factor out a xlog_wait_on_iclog helper
  xfs: merge xlog_cil_push into xlog_cil_push_work
  xfs: remove the di_version field from struct icdinode
  xfs: simplify a check in xfs_ioctl_setattr_check_cowextsize
  xfs: simplify di_flags2 inheritance in xfs_ialloc
  xfs: only check the superblock version for dinode size calculation
  xfs: add a new xfs_sb_version_has_v3inode helper
  xfs: fix unmount hang and memory leak on shutdown during quotaoff
  xfs: factor out quotaoff intent AIL removal and memory free
  ...
2020-04-02 13:02:07 -07:00
Linus Torvalds
7db83c070b New code for 5.7:
- Fix a regression where we broke the userspace hibernation driver by
    disallowing writes to the swap device.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAl542q0ACgkQ+H93GTRK
 tOun8A//QIAvIuMQl9k/S4lDqvVNAmSMJDdp0v3x+BOMBDmbqJeDO+D9u59nVWAP
 zun1Zp3weO7v8kMBPDyvTVhKP0Z9v8ogQj4yT22W0YiBsKgsaqM9tupc3NPm036V
 oPusLFC44RRXyLZSjBhNr3xYTBqeGmJMKBUGrnwYeQK2g87o3gi8s9KmVq3olp/L
 W/ZvFgmTl4FpbA1aNaMtZ1YBawu9wyQDvmtZtnD7xuXGKGsQjGUt20P7yuFu2Mb8
 vmUHNcCBG29j8Fwd+6Gub2Jg25BhLGBSjftLHcGdG8aRN4Y5DQ3w+rBwUD7fHQmi
 u0DXMnPIP8twsQPKwWabfZ3PMqyfUiz5rSnJGGd+T7uPP5xYvpKhYGm8IBPQb699
 2LY4NZKQqp9IWSbwmU7jSwCEl0x/GDMflF3frpfTmvCDvpW7TUQf8lJsVsF6OcNP
 uGJPz3AoE5ebt2XD+IWCurWrfn/nGnxp9ZEKjK69nm3BFXI0GRdqBq6lueBsh6re
 zKUoFp7IHIb4ET6V21JPq9iyKUlKLqgb+rpqcA4CwA4tvJZkZXVlYOdwi1CWse3o
 8o9xaDmW1murvc0XrnQu8Z8way1nkUYBBkhRJsHCdy8Qn2xA3fyVumZGichNNccO
 Mzu8+IKttCTBK8ZY6iAXsjbL61eR1vrr3GGbz4kh6dZy5fBX99c=
 =y7GN
 -----END PGP SIGNATURE-----

Merge tag 'vfs-5.7-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull hibernation fix from Darrick Wong:
 "Fix a regression where we broke the userspace hibernation driver by
  disallowing writes to the swap device"

* tag 'vfs-5.7-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  hibernate: Allow uswsusp to write to swap
2020-04-02 12:59:36 -07:00
Linus Torvalds
35a9fafe23 New iomap code for 5.7:
- Fix a broken tracepoint
 - Fix a broken comment
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAl5yOLYACgkQ+H93GTRK
 tOueKA/+O83EV/a8oI5/EEM95uoe5JRC4VUaCj3iDyMVEefQC8Phl3pUraQoG/z3
 d511bTvca70rBSYj9HaSoa3Wt3MTJTPy9RIxBIKaaumzTXMe4erfXZ/JRJIf5DSl
 JZs+Ujng5ythLR6ederr/Kn7LXg5MGax5I4j41JHCDiRp5xFaqRN+4Rib18jj4Lf
 WNlbwblixWzCeEeHhs+CNm9G7cy+wt84Qv0CTJjC/nThtDc2tOVFkI3EODX0oZH5
 R+KEbEStHebI9AZ0NIfDagoHQ926ROjAEpJn4VS/tOYbN1favrSE5RTnaNZ0asln
 c6XnGIPvpHcjsFztNFEuPXS9rP6aGNLic+P+V5TADjzY3M0TCXnIsYXFhEV23HNe
 2hprg6T7+KvcAaTdq3t5k2jjYC9AEiaxBLIJRGyTwYKmJPobvTXU9QTyJpA3KX3u
 mCAo8jJzl3XHcMrCcXA3xBVS8e23cAkQN5gwpvMIfOeGRr006iFAJS5MZ23Rqyk8
 k3w0V4vVWW3QnLYwJI+cGKanuhFrZ7PNulnqC4AmUdYpeyhmWoH2e1mYgU3JKNm9
 vF4zad/MYhp0xfEUopsLEE+F0sj4v1yUKEvPSoXxGYSycf9/KFa3/MQvF3akaOeX
 kQu29pzDeErFsdLzm+qQmt/xFHuSA5WP6ShO+0XC9uzhN/ezRNg=
 =2wnO
 -----END PGP SIGNATURE-----

Merge tag 'iomap-5.7-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull iomap updates from Darrick Wong:
 "We're fixing tracepoints and comments in this cycle, so there
  shouldn't be any surprises here.

  I anticipate sending a second pull request next week with a single bug
  fix for readahead, but it's still undergoing QA.

  Summary:

   - Fix a broken tracepoint

   - Fix a broken comment"

* tag 'iomap-5.7-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: fix comments in iomap_dio_rw
  iomap: Remove pgoff from tracepoints
2020-04-02 12:57:18 -07:00
Linus Torvalds
9c577491b9 Merge branch 'work.dotdot1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pathwalk sanitizing from Al Viro:
 "Massive pathwalk rewrite and cleanups.

  Several iterations have been posted; hopefully this thing is getting
  readable and understandable now. Pretty much all parts of pathname
  resolutions are affected...

  The branch is identical to what has sat in -next, except for commit
  message in "lift all calls of step_into() out of follow_dotdot/
  follow_dotdot_rcu", crediting Qian Cai for reporting the bug; only
  commit message changed there."

* 'work.dotdot1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (69 commits)
  lookup_open(): don't bother with fallbacks to lookup+create
  atomic_open(): no need to pass struct open_flags anymore
  open_last_lookups(): move complete_walk() into do_open()
  open_last_lookups(): lift O_EXCL|O_CREAT handling into do_open()
  open_last_lookups(): don't abuse complete_walk() when all we want is unlazy
  open_last_lookups(): consolidate fsnotify_create() calls
  take post-lookup part of do_last() out of loop
  link_path_walk(): sample parent's i_uid and i_mode for the last component
  __nd_alloc_stack(): make it return bool
  reserve_stack(): switch to __nd_alloc_stack()
  pick_link(): take reserving space on stack into a new helper
  pick_link(): more straightforward handling of allocation failures
  fold path_to_nameidata() into its only remaining caller
  pick_link(): pass it struct path already with normal refcounting rules
  fs/namei.c: kill follow_mount()
  non-RCU analogue of the previous commit
  helper for mount rootwards traversal
  follow_dotdot(): be lazy about changing nd->path
  follow_dotdot_rcu(): be lazy about changing nd->path
  follow_dotdot{,_rcu}(): massage loops
  ...
2020-04-02 12:30:08 -07:00
Linus Torvalds
d987ca1c6b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull exec/proc updates from Eric Biederman:
 "This contains two significant pieces of work: the work to sort out
  proc_flush_task, and the work to solve a deadlock between strace and
  exec.

  Fixing proc_flush_task so that it no longer requires a persistent
  mount makes improvements to proc possible. The removal of the
  persistent mount solves an old regression that that caused the hidepid
  mount option to only work on remount not on mount. The regression was
  found and reported by the Android folks. This further allows Alexey
  Gladkov's work making proc mount options specific to an individual
  mount of proc to move forward.

  The work on exec starts solving a long standing issue with exec that
  it takes mutexes of blocking userspace applications, which makes exec
  extremely deadlock prone. For the moment this adds a second mutex with
  a narrower scope that handles all of the easy cases. Which makes the
  tricky cases easy to spot. With a little luck the code to solve those
  deadlocks will be ready by next merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (25 commits)
  signal: Extend exec_id to 64bits
  pidfd: Use new infrastructure to fix deadlocks in execve
  perf: Use new infrastructure to fix deadlocks in execve
  proc: io_accounting: Use new infrastructure to fix deadlocks in execve
  proc: Use new infrastructure to fix deadlocks in execve
  kernel/kcmp.c: Use new infrastructure to fix deadlocks in execve
  kernel: doc: remove outdated comment cred.c
  mm: docs: Fix a comment in process_vm_rw_core
  selftests/ptrace: add test cases for dead-locks
  exec: Fix a deadlock in strace
  exec: Add exec_update_mutex to replace cred_guard_mutex
  exec: Move exec_mmap right after de_thread in flush_old_exec
  exec: Move cleanup of posix timers on exec out of de_thread
  exec: Factor unshare_sighand out of de_thread and call it separately
  exec: Only compute current once in flush_old_exec
  pid: Improve the comment about waiting in zap_pid_ns_processes
  proc: Remove the now unnecessary internal mount of proc
  uml: Create a private mount of proc for mconsole
  uml: Don't consult current to find the proc_mnt in mconsole_proc
  proc: Use a list of inodes to flush from proc
  ...
2020-04-02 11:22:17 -07:00
Mike Kravetz
87bf91d39b hugetlbfs: Use i_mmap_rwsem to address page fault/truncate race
hugetlbfs page faults can race with truncate and hole punch operations.
Current code in the page fault path attempts to handle this by 'backing
out' operations if we encounter the race.  One obvious omission in the
current code is removing a page newly added to the page cache.  This is
pretty straight forward to address, but there is a more subtle and
difficult issue of backing out hugetlb reservations.  To handle this
correctly, the 'reservation state' before page allocation needs to be
noted so that it can be properly backed out.  There are four distinct
possibilities for reservation state: shared/reserved, shared/no-resv,
private/reserved and private/no-resv.  Backing out a reservation may
require memory allocation which could fail so that needs to be taken
into account as well.

Instead of writing the required complicated code for this rare
occurrence, just eliminate the race.  i_mmap_rwsem is now held in read
mode for the duration of page fault processing.  Hold i_mmap_rwsem in
write mode when modifying i_size.  In this way, truncation can not
proceed when page faults are being processed.  In addition, i_size
will not change during fault processing so a single check can be made
to ensure faults are not beyond (proposed) end of file.  Faults can
still race with hole punch, but that race is handled by existing code
and the use of hugetlb_fault_mutex.

With this modification, checks for races with truncation in the page
fault path can be simplified and removed.  remove_inode_hugepages no
longer needs to take hugetlb_fault_mutex in the case of truncation.
Comments are expanded to explain reasoning behind locking.

Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Link: http://lkml.kernel.org/r/20200316205756.146666-3-mike.kravetz@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:32 -07:00
Mike Kravetz
c0d0381ade hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
Patch series "hugetlbfs: use i_mmap_rwsem for more synchronization", v2.

While discussing the issue with huge_pte_offset [1], I remembered that
there were more outstanding hugetlb races.  These issues are:

1) For shared pmds, huge PTE pointers returned by huge_pte_alloc can become
   invalid via a call to huge_pmd_unshare by another thread.
2) hugetlbfs page faults can race with truncation causing invalid global
   reserve counts and state.

A previous attempt was made to use i_mmap_rwsem in this manner as
described at [2].  However, those patches were reverted starting with [3]
due to locking issues.

To effectively use i_mmap_rwsem to address the above issues it needs to be
held (in read mode) during page fault processing.  However, during fault
processing we need to lock the page we will be adding.  Lock ordering
requires we take page lock before i_mmap_rwsem.  Waiting until after
taking the page lock is too late in the fault process for the
synchronization we want to do.

To address this lock ordering issue, the following patches change the lock
ordering for hugetlb pages.  This is not too invasive as hugetlbfs
processing is done separate from core mm in many places.  However, I don't
really like this idea.  Much ugliness is contained in the new routine
hugetlb_page_mapping_lock_write() of patch 1.

The only other way I can think of to address these issues is by catching
all the races.  After catching a race, cleanup, backout, retry ...  etc,
as needed.  This can get really ugly, especially for huge page
reservations.  At one time, I started writing some of the reservation
backout code for page faults and it got so ugly and complicated I went
down the path of adding synchronization to avoid the races.  Any other
suggestions would be welcome.

[1] https://lore.kernel.org/linux-mm/1582342427-230392-1-git-send-email-longpeng2@huawei.com/
[2] https://lore.kernel.org/linux-mm/20181222223013.22193-1-mike.kravetz@oracle.com/
[3] https://lore.kernel.org/linux-mm/20190103235452.29335-1-mike.kravetz@oracle.com
[4] https://lore.kernel.org/linux-mm/1584028670.7365.182.camel@lca.pw/
[5] https://lore.kernel.org/lkml/20200312183142.108df9ac@canb.auug.org.au/

This patch (of 2):

While looking at BUGs associated with invalid huge page map counts, it was
discovered and observed that a huge pte pointer could become 'invalid' and
point to another task's page table.  Consider the following:

A task takes a page fault on a shared hugetlbfs file and calls
huge_pte_alloc to get a ptep.  Suppose the returned ptep points to a
shared pmd.

Now, another task truncates the hugetlbfs file.  As part of truncation, it
unmaps everyone who has the file mapped.  If the range being truncated is
covered by a shared pmd, huge_pmd_unshare will be called.  For all but the
last user of the shared pmd, huge_pmd_unshare will clear the pud pointing
to the pmd.  If the task in the middle of the page fault is not the last
user, the ptep returned by huge_pte_alloc now points to another task's
page table or worse.  This leads to bad things such as incorrect page
map/reference counts or invalid memory references.

To fix, expand the use of i_mmap_rwsem as follows:
- i_mmap_rwsem is held in read mode whenever huge_pmd_share is called.
  huge_pmd_share is only called via huge_pte_alloc, so callers of
  huge_pte_alloc take i_mmap_rwsem before calling.  In addition, callers
  of huge_pte_alloc continue to hold the semaphore until finished with
  the ptep.
- i_mmap_rwsem is held in write mode whenever huge_pmd_unshare is called.

One problem with this scheme is that it requires taking i_mmap_rwsem
before taking the page lock during page faults.  This is not the order
specified in the rest of mm code.  Handling of hugetlbfs pages is mostly
isolated today.  Therefore, we use this alternative locking order for
PageHuge() pages.

         mapping->i_mmap_rwsem
           hugetlb_fault_mutex (hugetlbfs specific page fault mutex)
             page->flags PG_locked (lock_page)

To help with lock ordering issues, hugetlb_page_mapping_lock_write() is
introduced to write lock the i_mmap_rwsem associated with a page.

In most cases it is easy to get address_space via vma->vm_file->f_mapping.
However, in the case of migration or memory errors for anon pages we do
not have an associated vma.  A new routine _get_hugetlb_page_mapping()
will use anon_vma to get address_space in these cases.

Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Prakash Sangappa <prakash.sangappa@oracle.com>
Link: http://lkml.kernel.org/r/20200316205756.146666-2-mike.kravetz@oracle.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:32 -07:00
Peter Xu
3e69ad081c mm/userfaultfd: honor FAULT_FLAG_KILLABLE in fault path
Userfaultfd fault path was by default killable even if the caller does not
have FAULT_FLAG_KILLABLE.  That makes sense before in that when with gup
we don't have FAULT_FLAG_KILLABLE properly set before.  Now after previous
patch we've got FAULT_FLAG_KILLABLE applied even for gup code so it should
also make sense to let userfaultfd to honor the FAULT_FLAG_KILLABLE.

Because we're unconditionally setting FAULT_FLAG_KILLABLE in gup code
right now, this patch should have no functional change.  It also cleaned
the code a little bit by introducing some helpers.

Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160300.9941-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:30 -07:00
Peter Xu
c270a7eedc mm: introduce FAULT_FLAG_INTERRUPTIBLE
handle_userfaultfd() is currently the only one place in the kernel page
fault procedures that can respond to non-fatal userspace signals.  It was
trying to detect such an allowance by checking against USER & KILLABLE
flags, which was "un-official".

In this patch, we introduced a new flag (FAULT_FLAG_INTERRUPTIBLE) to show
that the fault handler allows the fault procedure to respond even to
non-fatal signals.  Meanwhile, add this new flag to the default fault
flags so that all the page fault handlers can benefit from the new flag.
With that, replacing the userfault check to this one.

Since the line is getting even longer, clean up the fault flags a bit too
to ease TTY users.

Although we've got a new flag and applied it, we shouldn't have any
functional change with this patch so far.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220195348.16302-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:30 -07:00
Peter Xu
ef429ee740 userfaultfd: don't retake mmap_sem to emulate NOPAGE
This patch removes the risk path in handle_userfault() then we will be
sure that the callers of handle_mm_fault() will know that the VMAs might
have changed.  Meanwhile with previous patch we don't lose responsiveness
as well since the core mm code now can handle the nonfatal userspace
signals even if we return VM_FAULT_RETRY.

Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160234.9646-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:29 -07:00
Roman Gushchin
f4b00eab50 mm: kmem: rename memcg_kmem_(un)charge() into memcg_kmem_(un)charge_page()
Rename (__)memcg_kmem_(un)charge() into (__)memcg_kmem_(un)charge_page()
to better reflect what they are actually doing:

1) call __memcg_kmem_(un)charge_memcg() to actually charge or uncharge
   the current memcg

2) set or clear the PageKmemcg flag

Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Link: http://lkml.kernel.org/r/20200109202659.752357-4-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:28 -07:00
Kees Cook
c537338c05 fs_parse: remove pr_notice() about each validation
This notice fills my boot logs with scary-looking asterisks but doesn't
really tell me anything.  Let's just remove it; validation errors are
already reported separately, so this is just a redundant list of
filesystems.

$ dmesg | grep VALIDATE
[    0.306256] *** VALIDATE tmpfs ***
[    0.307422] *** VALIDATE proc ***
[    0.308355] *** VALIDATE cgroup ***
[    0.308741] *** VALIDATE cgroup2 ***
[    0.813256] *** VALIDATE bpf ***
[    0.815272] *** VALIDATE ramfs ***
[    0.815665] *** VALIDATE hugetlbfs ***
[    0.876970] *** VALIDATE nfs ***
[    0.877383] *** VALIDATE nfs4 ***

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Link: http://lkml.kernel.org/r/202003061617.A8835CAAF@keescook
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:26 -07:00
Matthew Wilcox (Oracle)
4ceb229f66 ocfs2: use memalloc_nofs_save instead of memalloc_noio_save
OCFS2 doesn't mind if memory reclaim makes I/Os happen; it just cares that
it won't be reentered, so it can use memalloc_nofs_save() instead of
memalloc_noio_save().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200326200214.1102-1-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:26 -07:00
Takashi Iwai
d293d3af2d ocfs2: use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the actual
output size, the succeeding calls may go beyond the given buffer limit.
Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200311093516.25300-1-tiwai@suse.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:26 -07:00
wangjian
0434c9f404 ocfs2: roll back the reference count modification of the parent directory if an error occurs
Under some conditions, the directory cannot be deleted.  The specific
scenarios are as follows: (for example, /mnt/ocfs2 is the mount point)

1. Create the /mnt/ocfs2/p_dir directory.  At this time, the i_nlink
   corresponding to the inode of the /mnt/ocfs2/p_dir directory is equal
   to 2.

2. During the process of creating the /mnt/ocfs2/p_dir/s_dir
   directory, if the call to the inc_nlink function in ocfs2_mknod
   succeeds, the functions such as ocfs2_init_acl,
   ocfs2_init_security_set, and ocfs2_dentry_attach_lock fail.  At this
   time, the i_nlink corresponding to the inode of the /mnt/ocfs2/p_dir
   directory is equal to 3, but /mnt/ocfs2/p_dir/s_dir is not added to the
   /mnt/ocfs2/p_dir directory entry.

3. Delete the /mnt/ocfs2/p_dir directory (rm -rf /mnt/ocfs2/p_dir).
   At this time, it is found that the i_nlink corresponding to the inode
   corresponding to the /mnt/ocfs2/p_dir directory is equal to 3.
   Therefore, the /mnt/ocfs2/p_dir directory cannot be deleted.

Signed-off-by: Jian wang <wangjian161@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/a44f6666-bbc4-405e-0e6c-0f4e922eeef6@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:26 -07:00
Gustavo A. R. Silva
95f3427c24 ocfs2: ocfs2_fs.h: replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by this
change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied.  As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://urldefense.com/v3/__https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html__;!!GqivPVa7Brio!OKPotRhYhHbCG2kibo8Q6_6CuKaa28d_74h1svxyR6rbshrK2L_BdrQpNbvJWBWb40QCkg$
[2] https://urldefense.com/v3/__https://github.com/KSPP/linux/issues/21__;!!GqivPVa7Brio!OKPotRhYhHbCG2kibo8Q6_6CuKaa28d_74h1svxyR6rbshrK2L_BdrQpNbvJWBUhNn9M6g$
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200309202155.GA8432@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:26 -07:00
Gustavo A. R. Silva
8cb92435e2 ocfs2: dlm: replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by this
change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied.  As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://urldefense.com/v3/__https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html__;!!GqivPVa7Brio!OVOYL_CouISa5L1Lw-20EEFQntw6cKMx-j8UdY4z78uYgzKBUFcfpn50GaurvbV5v7YiUA$
[2] https://urldefense.com/v3/__https://github.com/KSPP/linux/issues/21__;!!GqivPVa7Brio!OVOYL_CouISa5L1Lw-20EEFQntw6cKMx-j8UdY4z78uYgzKBUFcfpn50GaurvbXs8Eh8eg$
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200309202016.GA8210@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Gustavo A. R. Silva
fa803cf8f3 ocfs2: cluster: replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by this
change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied.  As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://urldefense.com/v3/__https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html__;!!GqivPVa7Brio!NzMr-YRl2zy-K3lwLVVatz7x0uD2z7-ykQag4GrGigxmfWU8TWzDy6xrkTiW3hYl00czlw$
[2] https://urldefense.com/v3/__https://github.com/KSPP/linux/issues/21__;!!GqivPVa7Brio!NzMr-YRl2zy-K3lwLVVatz7x0uD2z7-ykQag4GrGigxmfWU8TWzDy6xrkTiW3hYHG1nAnw$
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200309201907.GA8005@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Gustavo A. R. Silva
3c9210d45d ocfs2: replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension
to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning in
case the flexible array does not occur last in the structure, which will
help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by this
change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied.  As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200213160244.GA6088@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Jules Irenge
185a73216f ocfs2: add missing annotations for ocfs2_refcount_cache_lock() and ocfs2_refcount_cache_unlock()
Sparse reports warnings at ocfs2_refcount_cache_lock()
	and ocfs2_refcount_cache_unlock()

warning: context imbalance in ocfs2_refcount_cache_lock()
	- wrong count at exit
warning: context imbalance in ocfs2_refcount_cache_unlock()
	- unexpected unlock

The root cause is the missing annotation at ocfs2_refcount_cache_lock()
and at ocfs2_refcount_cache_unlock()

Add the missing __acquires(&rf->rf_lock) annotation to
ocfs2_refcount_cache_lock()

Add the missing __releases(&rf->rf_lock) annotation to
ocfs2_refcount_cache_unlock()

Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/20200224204130.18178-1-jbi.octave@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Alex Shi
1a5692e477 ocfs2: remove useless err
We don't need 'err' in these 2 places, better to remove them.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: ChenGang <cg.chen@huawei.com>
Cc: Richard Fontana <rfontana@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1579577836-251879-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
wangyan
41f4dc8331 ocfs2: correct annotation from "l_next_rec" to "l_next_free_rec"
Correct annotation from "l_next_rec" to "l_next_free_rec"

Signed-off-by: Yan Wang <wangyan122@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Link: http://lkml.kernel.org/r/5e76c953-3479-1280-023c-ad05e4c75608@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
wangyan
cb5bc8557a ocfs2: there is no need to log twice in several functions
There is no need to log twice in several functions.

Signed-off-by: Yan Wang <wangyan122@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jun Piao <piaojun@huawei.com>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Link: http://lkml.kernel.org/r/77eec86a-f634-5b98-4f7d-0cd15185a37b@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Alex Shi
e0369873e6 ocfs2: remove dlm_lock_is_remote
This macro has been unused since it was introduced.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/1579578203-254451-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Alex Shi
31cc0c8029 ocfs2: use OCFS2_SEC_BITS in macro
This macro should be used.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/1579577840-251956-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Alex Shi
8e6ef3731e ocfs2: remove unused macros
O2HB_DEFAULT_BLOCK_BITS/DLM_THREAD_MAX_ASTS/DLM_MIGRATION_RETRY_MS and
OCFS2_MAX_RESV_WINDOW_BITS/OCFS2_MIN_RESV_WINDOW_BITS have been unused
since commit 66effd3c68 ("ocfs2/dlm: Do not migrate resource to a node
that is leaving the domain").

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: ChenGang <cg.chen@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Fontana <rfontana@redhat.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/1579577827-251796-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Alex Shi
ee9dc325ac ocfs2: remove FS_OCFS2_NM
This macro is unused since commit ab09203e30 ("sysctl fs: Remove dead
binary sysctl support").

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Link: http://lkml.kernel.org/r/1579577812-251572-1-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:25 -07:00
Al Viro
99a4a90c8e lookup_open(): don't bother with fallbacks to lookup+create
We fall back to lookup+create (instead of atomic_open) in several cases:
	1) we don't have write access to filesystem and O_TRUNC is
present in the flags.  It's not something we want ->atomic_open() to
see - it just might go ahead and truncate the file.  However, we can
pass it the flags sans O_TRUNC - eventually do_open() will call
handle_truncate() anyway.
	2) we have O_CREAT | O_EXCL and we can't write to parent.
That's going to be an error, of course, but we want to know _which_
error should that be - might be EEXIST (if file exists), might be
EACCES or EROFS.  Simply stripping O_CREAT (and checking if we see
ENOENT) would suffice, if not for O_EXCL.  However, we used to have
->atomic_open() fully responsible for rejecting O_CREAT | O_EXCL
on existing file and just stripping O_CREAT would've disarmed
those checks.  With nothing downstream to catch the problem -
FMODE_OPENED used to be "don't bother with EEXIST checks,
->atomic_open() has done those".  Now EEXIST checks downstream
are skipped only if FMODE_CREATED is set - FMODE_OPENED alone
is not enough.  That has eliminated the need to fall back onto
lookup+create path in this case.
	3) O_WRONLY or O_RDWR when we have no write access to
filesystem, with nothing else objectionable.  Fallback is
(and had always been) pointless.

IOW, we don't really need that fallback; all we need in such
cases is to trim O_TRUNC and O_CREAT properly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:31 -04:00
Al Viro
d489cf9a3e atomic_open(): no need to pass struct open_flags anymore
argument had been unused since 1643b43fbd (lookup_open(): lift the
"fallback to !O_CREAT" logics from atomic_open()) back in 2016

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:31 -04:00
Al Viro
ff326a3299 open_last_lookups(): move complete_walk() into do_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:30 -04:00
Al Viro
b94e0b32c8 open_last_lookups(): lift O_EXCL|O_CREAT handling into do_open()
Currently path_openat() has "EEXIST on O_EXCL|O_CREAT" checks done on one
of the ways out of open_last_lookups().  There are 4 cases:
	1) the last component is . or ..; check is not done.
	2) we had FMODE_OPENED or FMODE_CREATED set while in lookup_open();
check is not done.
	3) symlink to be traversed is found; check is not done (nor
should it be)
	4) everything else: check done (before complete_walk(), even).

In case (1) O_EXCL|O_CREAT ends up failing with -EISDIR - that's
	open("/tmp/.", O_CREAT|O_EXCL, 0600)
Note that in the same conditions
	open("/tmp", O_CREAT|O_EXCL, 0600)
would have yielded EEXIST.  Either error is allowed, switching to -EEXIST
in these cases would've been more consistent.

Case (2) is more subtle; first of all, if we have FMODE_CREATED set, the
object hadn't existed prior to the call.  The check should not be done in
such a case.  The rest is problematic, though - we have
	FMODE_OPENED set (i.e. it went through ->atomic_open() and got
successfully opened there)
	FMODE_CREATED is *NOT* set
	O_CREAT and O_EXCL are both set.
Any such case is a bug - either we failed to set FMODE_CREATED when we
had, in fact, created an object (no such instances in the tree) or
we have opened a pre-existing file despite having had both O_CREAT and
O_EXCL passed.  One of those was, in fact caught (and fixed) while
sorting out this mess (gfs2 on cold dcache).  And in such situations
we should fail with EEXIST.

Note that for (1) and (4) FMODE_CREATED is not set - for (1) there's nothing
in handle_dots() to set it, for (4) we'd explicitly checked that.

And (1), (2) and (4) are exactly the cases when we leave the loop in
the caller, with do_open() called immediately after that loop.  IOW, we
can move the check over there, and make it

	If we have O_CREAT|O_EXCL and after successful pathname resolution
FMODE_CREATED is *not* set, we must have run into a preexisting file and
should fail with EEXIST.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:30 -04:00
Al Viro
72287417ab open_last_lookups(): don't abuse complete_walk() when all we want is unlazy
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:29 -04:00
Al Viro
f7bb959d96 open_last_lookups(): consolidate fsnotify_create() calls
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:28 -04:00
Al Viro
c5971b8c63 take post-lookup part of do_last() out of loop
now we can have open_last_lookups() directly from the loop in
path_openat() - the rest of do_last() never returns a symlink
to follow, so we can bloody well leave the loop first.

Rename the rest of that thing from do_last() to do_open() and
make it return an int.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:28 -04:00
Al Viro
0f70595301 link_path_walk(): sample parent's i_uid and i_mode for the last component
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:27 -04:00
Al Viro
60ef60c7d7 __nd_alloc_stack(): make it return bool
... and adjust the caller (reserve_stack()).  Rename to nd_alloc_stack(),
while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:26 -04:00
Al Viro
4542576b79 reserve_stack(): switch to __nd_alloc_stack()
expand the call of nd_alloc_stack() into it (and don't
recheck the depth on the second call)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:26 -04:00
Al Viro
49055906af pick_link(): take reserving space on stack into a new helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:25 -04:00
Al Viro
aef9404d8c pick_link(): more straightforward handling of allocation failures
pick_link() needs to push onto stack; we start with using two-element
array embedded into struct nameidata and the first time we need
more than that we switch to separately allocated array.

Allocation can fail, of course, and handling of that would be simple
enough - we need to drop 'link' and bugger off.  However, the things
get more complicated in RCU mode.  There we must do GFP_ATOMIC
allocation.  If that fails, we try to switch to non-RCU mode and
repeat the allocation.

To switch to non-RCU mode we need to grab references to 'link' and
to everything in nameidata.  The latter done by unlazy_walk();
the former - legitimize_path().  'link' must go first - after
unlazy_walk() we are out of RCU-critical period and it's too
late to call legitimize_path() since the references in link->mnt
and link->dentry might be pointing to freed and reused memory.

So we do legitimize_path(), then unlazy_walk().  And that's where
it gets too subtle: what to do if the former fails?  We MUST
do path_put(link) to avoid leaks.  And we can't do that under
rcu_read_lock().  Solution in mainline was to empty then nameidata
manually, drop out of RCU mode and then do put_path().

In effect, we open-code the things eventual terminate_walk()
would've done on error in RCU mode.  That looks badly out of place
and confusing.  We could add a comment along the lines of the
explanation above, but... there's a simpler solution.  Call
unlazy_walk() even if legitimaze_path() fails.  It will take
us out of RCU mode, so we'll be able to do path_put(link).

Yes, it will do unnecessary work - attempt to grab references
on the stuff in nameidata, only to have them dropped as soon
as we return the error to upper layer and get terminate_walk()
called there.  So what?  We are thoroughly off the fast path
by that point - we had GFP_ATOMIC allocation fail, we had
->d_seq or mount_lock mismatch and we are about to try walking
the same path from scratch in non-RCU mode.  Which will need
to do the same allocation, this time with GFP_KERNEL, so it will
be able to apply memory pressure for blocking stuff.

Compared to that the cost of several lockref_get_not_dead()
is noise.  And the logics become much easier to understand
that way.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:25 -04:00
Al Viro
c99687a03a fold path_to_nameidata() into its only remaining caller
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:24 -04:00
Al Viro
84f0cd9e83 pick_link(): pass it struct path already with normal refcounting rules
step_into() tries to avoid grabbing and dropping mount references
on the steps that do not involve crossing mountpoints (which is
obviously the majority of cases).  So it uses a local struct path
with unusual refcounting rules - path.mnt is pinned if and only if
it's not equal to nd->path.mnt.

We used to have similar beasts all over the place and we had quite
a few bugs crop up in their handling - it's easy to get confused
when changing e.g. cleanup on failure exits (or adding a new check,
etc.)

Now that's mostly gone - the step_into() instance (which is what
we need them for) is the only one left.  It is exposed to mount
traversal and it's (shortly) seen by pick_link().  Since pick_link()
needs to store it in link stack, where the normal rules apply,
it has to make sure that mount is pinned regardless of nd->path.mnt
value.  That's done on all calls of pick_link() and very early
in those.  Let's do that in the caller (step_into()) instead -
that way the fewer places need to be aware of such struct path
instances.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:23 -04:00
Al Viro
19f6028a01 fs/namei.c: kill follow_mount()
The only remaining caller (path_pts()) should be using follow_down()
anyway.  And clean path_pts() a bit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:23 -04:00
Al Viro
2aa3847085 non-RCU analogue of the previous commit
new helper: choose_mountpoint().  Wrapper around choose_mountpoint_rcu(),
similar to lookup_mnt() vs. __lookup_mnt().  follow_dotdot() switched to
it.  Now we don't grab mount_lock exclusive anymore; note that the
primitive used non-RCU mount traversals in other direction (lookup_mnt())
doesn't bother with that either - it uses mount_lock seqcount instead.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:22 -04:00
Al Viro
7ef482fa65 helper for mount rootwards traversal
The loops in follow_dotdot{_rcu()} are doing the same thing:
we have a mount and we want to find out how far up the chain
of mounts do we need to go.

We follow the chain of mount until we find one that is not
directly overmounting the root of another mount.  If such
a mount is found, we want the location it's mounted upon.
If we run out of chain (i.e. get to a mount that is not
mounted on anything else) or run into process' root, we
report failure.

On success, we want (in RCU case) d_seq of resulting location
sampled or (in non-RCU case) references to that location
acquired.

This commit introduces such primitive for RCU case and
switches follow_dotdot_rcu() to it; non-RCU case will be
go in the next commit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:21 -04:00
Al Viro
165200d6cb follow_dotdot(): be lazy about changing nd->path
Change nd->path only after the loop is done and only in case we hadn't
ended up finding ourselves in root.  Same for NO_XDEV check.

That separates the "check how far back do we need to go through the
mount stack" logics from the rest of .. traversal.

NOTE: path_get/path_put introduced here are temporary.  They will
go away later in the series.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:21 -04:00
Al Viro
efe772d628 follow_dotdot_rcu(): be lazy about changing nd->path
Change nd->path only after the loop is done and only in case we hadn't
ended up finding ourselves in root.  Same for NO_XDEV check.  Don't
recheck mount_lock on each step either.

That separates the "check how far back do we need to go through the
mount stack" logics from the rest of .. traversal.

Note that the sequence for d_seq/d_inode here is
	* sample mount_lock seqcount
...
	* sample d_seq
	* fetch d_inode
	* verify mount_lock seqcount
The last step makes sure that d_inode value we'd got matches d_seq -
it dentry is guaranteed to have been a mountpoint through the
entire thing, so its d_inode must have been stable.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:20 -04:00
Al Viro
12487f3067 follow_dotdot{,_rcu}(): massage loops
The logics in both of them is the same:
	while true
		if in process' root	// uncommon
			break
		if *not* in mount root	// normal case
			find the parent
			return
		if at absolute root	// very uncommon
			break
		move to underlying mountpoint
	report that we are in root

Pull the common path out of the loop:
	if in process' root		// uncommon
		goto in_root
	if unlikely(in mount root)
		while true
			if at absolute root
				goto in_root
			move to underlying mountpoint
			if in process' root
				goto in_root
			if in mount root
				break;
	find the parent	// we are not in mount root
	return
in_root:
	report that we are in root

The reason for that transformation is that we get to keep the
common path straight *and* get a separate block for "move
through underlying mountpoints", which will allow to sanitize
NO_XDEV handling there.  What's more, the pared-down loops
will be easier to deal with - in particular, non-RCU case
has no need to grab mount_lock and rewriting it to the
form that wouldn't do that is a non-trivial change.  Better
do that with less stuff getting in the way...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:09:19 -04:00
Al Viro
c2df196876 lift all calls of step_into() out of follow_dotdot/follow_dotdot_rcu
lift step_into() into handle_dots() (where they merge with each other);
have follow_... return dentry and pass inode/seq to the caller.

[braino fix folded; kudos to Qian Cai <cai@lca.pw> for reporting it]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-04-02 01:07:30 -04:00
Linus Torvalds
72f35423e8 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Fix out-of-sync IVs in self-test for IPsec AEAD algorithms

  Algorithms:
   - Use formally verified implementation of x86/curve25519

  Drivers:
   - Enhance hwrng support in caam

   - Use crypto_engine for skcipher/aead/rsa/hash in caam

   - Add Xilinx AES driver

   - Add uacce driver

   - Register zip engine to uacce in hisilicon

   - Add support for OCTEON TX CPT engine in marvell"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (162 commits)
  crypto: af_alg - bool type cosmetics
  crypto: arm[64]/poly1305 - add artifact to .gitignore files
  crypto: caam - limit single JD RNG output to maximum of 16 bytes
  crypto: caam - enable prediction resistance in HRWNG
  bus: fsl-mc: add api to retrieve mc version
  crypto: caam - invalidate entropy register during RNG initialization
  crypto: caam - check if RNG job failed
  crypto: caam - simplify RNG implementation
  crypto: caam - drop global context pointer and init_done
  crypto: caam - use struct hwrng's .init for initialization
  crypto: caam - allocate RNG instantiation descriptor with GFP_DMA
  crypto: ccree - remove duplicated include from cc_aead.c
  crypto: chelsio - remove set but not used variable 'adap'
  crypto: marvell - enable OcteonTX cpt options for build
  crypto: marvell - add the Virtual Function driver for CPT
  crypto: marvell - add support for OCTEON TX CPT engine
  crypto: marvell - create common Kconfig and Makefile for Marvell
  crypto: arm/neon - memzero_explicit aes-cbc key
  crypto: bcm - Use scnprintf() for avoiding potential buffer overflow
  crypto: atmel-i2c - Fix wakeup fail
  ...
2020-04-01 14:47:40 -07:00