Commit Graph

56547 Commits

Author SHA1 Message Date
Nikolay Borisov
7087a9d8db btrfs: Remove extent_io_ops::writepage_end_io_hook
This callback is ony ever called for data page writeout so there is no
need to actually abstract it via extent_io_ops. Lets just export it,
remove the definition of the callback and call it directly in the
functions that invoke the callback. Also rename the function to
btrfs_writepage_endio_finish_ordered since what it really does is
account finished io in the ordered extent data structures.  No
functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:28 +01:00
Nikolay Borisov
d75855b451 btrfs: Remove extent_io_ops::writepage_start_hook
This hook is called only from __extent_writepage_io which is already
called only from the data page writeout path. So there is no need to
make an indirect call via extent_io_ops. This patch just removes the
callback definition, exports the callback function and calls it directly
at the only call site. Also give the function a more descriptive name.
No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
5eaad97af8 btrfs: Remove extent_io_ops::fill_delalloc
This callback is called only from writepage_delalloc which in turn is
guaranteed to be called from the data page writeout path. In the end
there is no reason to have the call to this function to be indrected via
the extent_io_ops structure. This patch removes the callback definition,
exports the function and calls it directly. No functional changes.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ rename to btrfs_run_delalloc_range ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Nikolay Borisov
06f2548f9d btrfs: Add function to distinguish between data and btree inode
This will be used in future patches that remove the optional
extent_io_ops callbacks.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
05a37c4860 btrfs: volumes: Make sure no dev extent is beyond device boundary
Add extra dev extent end check against device boundary.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
5eb193812a btrfs: volumes: Make sure there is no overlap of dev extents at mount time
Enhance btrfs_verify_dev_extents() to remember previous checked dev
extents, so it can verify no dev extents can overlap.

Analysis from Hans:

"Imagine allocating a DATA|DUP chunk.

 In the chunk allocator, we first set...
   max_stripe_size = SZ_1G;
   max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE
 ... which is 10GiB.

 Then...
   /* we don't want a chunk larger than 10% of writeable space */
   max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
       		 max_chunk_size);

 Imagine we only have one 7880MiB block device in this filesystem. Now
 max_chunk_size is down to 788MiB.

 The next step in the code is to search for max_stripe_size * dev_stripes
 amount of free space on the device, which is in our example 1GiB * 2 =
 2GiB. Imagine the device has exactly 1578MiB free in one contiguous
 piece. This amount of bytes will be put in devices_info[ndevs - 1].max_avail

 Next we recalculate the stripe_size (which is actually the device extent
 length), based on the actual maximum amount of available raw disk space:
   stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);

 stripe_size is now 789MiB

 Next we do...
   data_stripes = num_stripes / ncopies
 ...where data_stripes ends up as 1, because num_stripes is 2 (the amount
 of device extents we're going to have), and DUP has ncopies 2.

 Next there's a check...
   if (stripe_size * data_stripes > max_chunk_size)
 ...which matches because 789MiB * 1 > 788MiB.

 We go into the if code, and next is...
   stripe_size = div_u64(max_chunk_size, data_stripes);
 ...which resets stripe_size to max_chunk_size: 788MiB

 Next is a fun one...
   /* bump the answer up to a 16MB boundary */
   stripe_size = round_up(stripe_size, SZ_16M);
 ...which changes stripe_size from 788MiB to 800MiB.

 We're not done changing stripe_size yet...
   /* But don't go higher than the limits we found while searching
    * for free extents
    */
   stripe_size = min(devices_info[ndevs - 1].max_avail,
       	      stripe_size);

 This is bad. max_avail is twice the stripe_size (we need to fit 2 device
 extents on the same device for DUP).

 The result here is that 800MiB < 1578MiB, so it's unchanged. However,
 the resulting DUP chunk will need 1600MiB disk space, which isn't there,
 and the second dev_extent might extend into the next thing (next
 dev_extent? end of device?) for 22MiB.

 The last shown line of code relies on a situation where there's twice
 the value of stripe_size present as value for the variable stripe_size
 when it's DUP. This was actually the case before commit 92e222df7b
 "btrfs: alloc_chunk: fix DUP stripe size handling", from which I quote:
   "[...] in the meantime there's a check to see if the stripe_size does
 not exceed max_chunk_size. Since during this check stripe_size is twice
 the amount as intended, the check will reduce the stripe_size to
 max_chunk_size if the actual correct to be used stripe_size is more than
 half the amount of max_chunk_size."

 In the previous version of the code, the 16MiB alignment (why is this
 done, by the way?) would result in a 50% chance that it would actually
 do an 8MiB alignment for the individual dev_extents, since it was
 operating on double the size. Does this matter?

 Does it matter that stripe_size can be set to anything which is not
 16MiB aligned because of the amount of remaining available disk space
 which is just taken?

 What is the main purpose of this round_up?

 The most straightforward thing to do seems something like...
   stripe_size = min(
       div_u64(devices_info[ndevs - 1].max_avail, dev_stripes),
       stripe_size
   )
 ..just putting half of the max_avail into stripe_size."

Link: https://lore.kernel.org/linux-btrfs/b3461a38-e5f8-f41d-c67c-2efac8129054@mendix.com/
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ add analysis from report ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:27 +01:00
Qu Wenruo
e72d79d6bc btrfs: Refactor find_free_extent loops update into find_free_extent_update_loop
We have a complex loop design for find_free_extent(), that has different
behavior for each loop, some even includes new chunk allocation.

Instead of putting such a long code into find_free_extent() and makes it
harder to read, just extract them into find_free_extent_update_loop().

With all the cleanups, the main find_free_extent() should be pretty
barebone:

find_free_extent()
|- Iterate through all block groups
|  |- Get a valid block group
|  |- Try to do clustered allocation in that block group
|  |- Try to do unclustered allocation in that block group
|  |- Check if the result is valid
|  |  |- If valid, then exit
|  |- Jump to next block group
|
|- Push harder to find free extents
   |- If not found, re-iterate all block groups

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
[ copy callchain from changelog to function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
e1a4184815 btrfs: Refactor unclustered extent allocation into find_free_extent_unclustered()
This patch will extract unclsutered extent allocation code into
find_free_extent_unclustered().

And this helper function will use return value to indicate what to do
next.

This should make find_free_extent() a little easier to read.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
[Update merge conflict with fb5c39d7a8 ("btrfs: don't use ctl->free_space for max_extent_size")]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
d06e3bb690 btrfs: Refactor clustered extent allocation into find_free_extent_clustered
We have two main methods to find free extents inside a block group:

1) clustered allocation
2) unclustered allocation

This patch will extract the clustered allocation into
find_free_extent_clustered() to make it a little easier to read.

Instead of jumping between different labels in find_free_extent(), the
helper function will use return value to indicate different behavior.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
b4bd745d12 btrfs: Introduce find_free_extent_ctl structure for later rework
Instead of tons of different local variables in find_free_extent(),
extract them into find_free_extent_ctl structure, and add better
explanation for them.

Some modification may looks redundant, but will later greatly simplify
function parameter list during find_free_extent() refactor.

Also add two comments to co-operate with fb5c39d7a8 ("btrfs: don't use
ctl->free_space for max_extent_size"), to make ffe_ctl->max_extent_size
update more reader-friendly.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Lu Fengqi
e2907c1a6a btrfs: extent-tree: Detect bytes_pinned underflow earlier
Introduce a new wrapper update_bytes_pinned to replace open coded
bytes_pinned modifiers. Now the underflows of space_info::bytes_pinned
get detected and reported.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:26 +01:00
Qu Wenruo
9f9b8e8d0e btrfs: extent-tree: Detect bytes_may_use underflow earlier
Although we have space_info::bytes_may_use underflow detection in
btrfs_free_reserved_data_space_noquota(), we have more callers who are
subtracting number from space_info::bytes_may_use.

So instead of doing underflow detection for every caller, introduce a
new wrapper update_bytes_may_use() to replace open coded bytes_may_use
modifiers.

This also introduce a macro to declare more wrappers, but currently
space_info::bytes_may_use is the mostly interesting one.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
85dd506c8e Btrfs: remove no longer used stuff for tracking pending ordered extents
Tracking pending ordered extents per transaction was introduced in commit
50d9aa99bd ("Btrfs: make sure logged extents complete in the current
transaction V3") and later updated in commit 161c3549b4 ("Btrfs: change
how we wait for pending ordered extents").

However now that on fsync we always wait for ordered extents to complete
before logging, done in commit 5636cf7d6d ("btrfs: remove the logged
extents infrastructure"), we no longer need the stuff to track for pending
ordered extents, which was not completely removed in the mentioned commit.
So remove the remaining of the pending ordered extents infrastructure.

Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Filipe Manana
ce02f03266 Btrfs: remove no longer used logged range variables when logging extents
The logged_start and logged_end variables, at btrfs_log_changed_extents,
were added in commit 8c6c592831 ("btrfs: log csums for all modified
extents"). However since the recent simplification for fsync, which makes
us wait for all ordered extents to complete before logging extents, we
no longer need those variables. Commit a2120a473a ("btrfs: clean up the
left over logged_list usage") forgot to remove them.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-17 14:51:25 +01:00
Linus Torvalds
6531e115b7 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  scripts/spdxcheck.py: always open files in binary mode
  checkstack.pl: fix for aarch64
  userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered
  fs/iomap.c: get/put the page in iomap_page_create/release()
  hugetlbfs: call VM_BUG_ON_PAGE earlier in free_huge_page()
  memblock: annotate memblock_is_reserved() with __init_memblock
  psi: fix reference to kernel commandline enable
  arch/sh/include/asm/io.h: provide prototypes for PCI I/O mapping in asm/io.h
  mm/sparse: add common helper to mark all memblocks present
  mm: introduce common STRUCT_PAGE_MAX_SHIFT define
  alpha: fix hang caused by the bootmem removal
2018-12-14 15:35:30 -08:00
Andrea Arcangeli
01e881f5a1 userfaultfd: check VM_MAYWRITE was set after verifying the uffd is registered
Calling UFFDIO_UNREGISTER on virtual ranges not yet registered in uffd
could trigger an harmless false positive WARN_ON.  Check the vma is
already registered before checking VM_MAYWRITE to shut off the false
positive warning.

Link: http://lkml.kernel.org/r/20181206212028.18726-2-aarcange@redhat.com
Cc: <stable@vger.kernel.org>
Fixes: 29ec90660d ("userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: syzbot+06c7092e7d71218a2c16@syzkaller.appspotmail.com
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
Piotr Jaroszynski
61c6de6672 fs/iomap.c: get/put the page in iomap_page_create/release()
migrate_page_move_mapping() expects pages with private data set to have
a page_count elevated by 1.  This is what used to happen for xfs through
the buffer_heads code before the switch to iomap in commit 82cb14175e
("xfs: add support for sub-pagesize writeback without buffer_heads").
Not having the count elevated causes move_pages() to fail on memory
mapped files coming from xfs.

Make iomap compatible with the migrate_page_move_mapping() assumption by
elevating the page count as part of iomap_page_create() and lowering it
in iomap_page_release().

It causes the move_pages() syscall to misbehave on memory mapped files
from xfs.  It does not not move any pages, which I suppose is "just" a
perf issue, but it also ends up returning a positive number which is out
of spec for the syscall.  Talking to Michal Hocko, it sounds like
returning positive numbers might be a necessary update to move_pages()
anyway though
(https://lkml.kernel.org/r/20181116114955.GJ14706@dhcp22.suse.cz).

I only hit this in tests that verify that move_pages() actually moved
the pages.  The test also got confused by the positive return from
move_pages() (it got treated as a success as positive numbers were not
expected and not handled) making it a bit harder to track down what's
going on.

Link: http://lkml.kernel.org/r/20181115184140.1388751-1-pjaroszynski@nvidia.com
Fixes: 82cb14175e ("xfs: add support for sub-pagesize writeback without buffer_heads")
Signed-off-by: Piotr Jaroszynski <pjaroszynski@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Brian Foster <bfoster@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-14 15:05:45 -08:00
Linus Torvalds
380ef2c9ad for-linus-20181214
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAlwUCecQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpsAvD/9Uwn/Mthw/w3BBHL1eVjFnCGHJ8/zVDSSu
 /XaP3nXugHicL7Je2EyHs0l4teUC42nIU7SQ+9B/UtyXA+usNvV7YEYqTD0U4ZYy
 gLuBL70f6L17uDq5821jR4e64Q3sDy/OgcTpKu3VwnJPYUhJpQuU7fKqN4zi7Asn
 5sI4KD99txmFMRNu33uusy98kJ4w5aeg6W1ACP7AxXYjyCY6Chi/7go8fEEK1Szb
 9jx0BhbscuZplvvzHw3WAHAaVGGUIjLlmUdqJOisj/GVnCck2IqKqhXND9H/WNWk
 FmzJeNTIq9Ag6kKN2WJ6xweNF6U+0Kb1Nn3F4jhoaVBhLxhpsjZ6BdHGWiT5wu4T
 xd+hIC4pykA7Y7CqPfpbNZzriX4SJd508XerVjfBmgWIumJLG2D2IfquHmT0udRw
 Qlb8pa3na5/dWXYbCOSjQdeBC5vCKCUuGnw15F5wA293khBNGiXVlztwCNgrkclQ
 4IpAEUYpRZiK138hDx/BL++yanALYdPHHUS4HtwVMhpi89Bel3FioNzGaaBlElZc
 mdSCyHc0RC7uMPMEbWl4bR+/cE3yjf43Gg3ftLaKLo5IQmZtu1pCEVXMatplZ1U/
 jbbwwPtx44RYV3gjPirr+YgF0smS9ZgMkkk3oLwysWSjAV5v+wW2MxjTBae3xaSJ
 VNoLhtefkw==
 =wHit
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-20181214' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Three small fixes for this week. contains:

   - spectre indexing fix for aio (Jeff)

   - fix for the previous zeroing bio fix, we don't need it for user
     mapped pages, and in fact it breaks some applications if we do
     (Keith)

   - allocation failure fix for null_blk with zoned (Shin'ichiro)"

* tag 'for-linus-20181214' of git://git.kernel.dk/linux-block:
  block: Fix null_blk_zoned creation failure with small number of zones
  aio: fix spectre gadget in lookup_ioctx
  block/bio: Do not zero user pages
2018-12-14 12:18:30 -08:00
Linus Torvalds
c19bf74fe4 Luis discovered a problem with the new copyfrom offload on the server
side.  Disable it for now.
 -----BEGIN PGP SIGNATURE-----
 
 iQFHBAABCAAxFiEEydHwtzie9C7TfviiSn/eOAIR84sFAlwTzaUTHGlkcnlvbW92
 QGdtYWlsLmNvbQAKCRBKf944AhHzi6eyB/97jq3Wzipr9I+Y3LwJeNKUu/8+LZ1d
 EDSbL1mgskzv0iX9fCds+wTzMksvm4V+n7I/DvoadbSEgTz2dUXYqoKBf3+4PEd1
 f7K69XHe8X/+ME3wGoOc4oLgNws0yGE5kcmiP5wB9Tlo8EkfqFuu6753wWi8xaUf
 so3TX9C+prqYmmhqRI8sesU84rMKjTkkK5dvIgVW4WLBJKsVAhmooyuRSwdVGZOv
 m7+8m7PWUJm8stMRDqsJ/0j4COiMeteQGQx6T67gkCUF6pBdJjO2IRNx2VAhybsx
 k/sMM/VfrQth/V4zsHZQD75BDQ+wu3Ncz8axIT5QYsAtuh9x0zr2av2e
 =kQS2
 -----END PGP SIGNATURE-----

Merge tag 'ceph-for-4.20-rc7' of https://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "Luis discovered a problem with the new copyfrom offload on the server
  side. Disable it for now"

* tag 'ceph-for-4.20-rc7' of https://github.com/ceph/ceph-client:
  ceph: make 'nocopyfrom' a default mount option
2018-12-14 09:22:14 -08:00
Linus Torvalds
e6333d72cb overlayfs fixes for 4.20-rc7
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCXBDMLgAKCRDh3BK/laaZ
 PPuRAP0X4zYWFh3mcGlcjjfzaP2W/3F8nVsXjo+YADi9nJ+wAwD+LIeL7zGr8Mw8
 EixiC+OJyL31O5ZOyHGoPEhhDz4O+Ao=
 =hWRh
 -----END PGP SIGNATURE-----

Merge tag 'ovl-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs fixes from Miklos Szeredi:
 "Needed to revert a patch, because it possibly introduces a security
  hole. Since the patch is basically a conceptual cleanup, not a bug
  fix, it's safe to revert. I'm not giving up on this, and discussions
  seemed to have reached an agreement over how to move forward, but that
  can wait 'till the next release.

  The other two patches are fixes for bugs introduced in recent
  releases"

* tag 'ovl-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  Revert "ovl: relax permission checking on underlying layers"
  ovl: fix decode of dir file handle with multi lower layers
  ovl: fix missing override creds in link of a metacopy upper
2018-12-12 18:19:44 -08:00
Linus Torvalds
70f4828201 fuse fixes for 4.20-rc7
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCXBDKkAAKCRDh3BK/laaZ
 PCXdAPwOWqLXpkBL76YaIbgFVzS+S5btlhHwVSZ0w/r7HGA3uQD+IgsHbky1MdSv
 rYyKcg+lVzA7GI7tcoQUhC2D9aZ8tAQ=
 =I0eL
 -----END PGP SIGNATURE-----

Merge tag 'fuse-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse fixes from Miklos Szeredi:
 "There's one patch fixing a minor but long lived bug, the others are
  fixing regressions introduced in this cycle"

* tag 'fuse-fixes-4.20-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: continue to send FUSE_RELEASEDIR when FUSE_OPEN returns ENOSYS
  fuse: Fix memory leak in fuse_dev_free()
  fuse: fix revalidation of attributes for permission check
  fuse: fix fsync on directory
  fuse: Add bad inode check in fuse_destroy_inode()
2018-12-12 18:17:35 -08:00
Chad Austin
2e64ff154c fuse: continue to send FUSE_RELEASEDIR when FUSE_OPEN returns ENOSYS
When FUSE_OPEN returns ENOSYS, the no_open bit is set on the connection.

Because the FUSE_RELEASE and FUSE_RELEASEDIR paths share code, this
incorrectly caused the FUSE_RELEASEDIR request to be dropped and never sent
to userspace.

Pass an isdir bool to distinguish between FUSE_RELEASE and FUSE_RELEASEDIR
inside of fuse_file_put.

Fixes: 7678ac5061 ("fuse: support clients that don't implement 'open'")
Cc: <stable@vger.kernel.org> # v3.14
Signed-off-by: Chad Austin <chadaustin@fb.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-11 21:47:28 +01:00
Jeff Moyer
a538e3ff9d aio: fix spectre gadget in lookup_ioctx
Matthew pointed out that the ioctx_table is susceptible to spectre v1,
because the index can be controlled by an attacker.  The below patch
should mitigate the attack for all of the aio system calls.

Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox <willy@infradead.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-11 11:45:50 -07:00
Luis Henriques
6f9718fe41 ceph: make 'nocopyfrom' a default mount option
Since we found a problem with the 'copy-from' operation after objects have
been truncated, offloading object copies to OSDs should be discouraged
until the issue is fixed.

Thus, this patch adds the 'nocopyfrom' mount option to the default mount
options which effectily means that remote copies won't be done in
copy_file_range unless they are explicitly enabled at mount time.

[ Adjust ceph_show_options() accordingly. ]

Link: https://tracker.ceph.com/issues/37378
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2018-12-11 18:22:17 +01:00
Takeshi Misawa
d72f70da60 fuse: Fix memory leak in fuse_dev_free()
When ntfs is unmounted, the following leak is
reported by kmemleak.

kmemleak report:

unreferenced object 0xffff880052bf4400 (size 4096):
  comm "mount.ntfs", pid 16530, jiffies 4294861127 (age 3215.836s)
  hex dump (first 32 bytes):
    00 44 bf 52 00 88 ff ff 00 44 bf 52 00 88 ff ff  .D.R.....D.R....
    10 44 bf 52 00 88 ff ff 10 44 bf 52 00 88 ff ff  .D.R.....D.R....
  backtrace:
    [<00000000bf4a2f8d>] fuse_fill_super+0xb22/0x1da0 [fuse]
    [<000000004dde0f0c>] mount_bdev+0x263/0x320
    [<0000000025aebc66>] mount_fs+0x82/0x2bf
    [<0000000042c5a6be>] vfs_kern_mount.part.33+0xbf/0x480
    [<00000000ed10cd5b>] do_mount+0x3de/0x2ad0
    [<00000000d59ff068>] ksys_mount+0xba/0xd0
    [<000000001bda1bcc>] __x64_sys_mount+0xba/0x150
    [<00000000ebe26304>] do_syscall_64+0x151/0x490
    [<00000000d25f2b42>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<000000002e0abd2c>] 0xffffffffffffffff

fuse_dev_alloc() allocate fud->pq.processing.
But this hash table is not freed.

Fix this by freeing fud->pq.processing.

Signed-off-by: Takeshi Misawa <jeliantsurux@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: be2ff42c5d ("fuse: Use hash table to link processing request")
2018-12-10 09:57:54 +01:00
Linus Torvalds
bc4caf186f a fix for smb3 direct i/o, a fix for CIFS DFS for stable and a minor cifs Kconfig fix
-----BEGIN PGP SIGNATURE-----
 
 iQGzBAABCgAdFiEE6fsu8pdIjtWE/DpLiiy9cAdyT1EFAlwMfwoACgkQiiy9cAdy
 T1FkqAv/Tty/Od1u3r/il26vogLunG9JvmC62upgfpb684isEOnYn0oaT9FElunB
 C43FXF8Zw73zKv/9IqmLExNGZJ0Jm+5eCjnGX+e05QWN8ais91V2IW+4JMLwCga3
 KWBD0V1SBa355cObpvWe1WzrIzm1lwa3aCO/lpENo7Ph+kZXcFVIuOPRRxwLOUU9
 dkZCtvs5Pb8LVu2k1/jUXh1hqibUGR3V46txDMH6oomsLNV97xTC9URBCbpeWb3f
 x4mpUeWP3DnUyK8TTr3W1MWh1jlUHg3/8yDHfCuxuluAgRFQpI8Eru18XE8abnkz
 loFu9eLVT6iwJAlzmkXFF4cGi8LXqz3x4Z+1DopH2S2DBwedw9Tc1dptwOuUbpfg
 SO4jMOaNXOUSnN+0pCdEiO1z/Nc0YaNg++5AvGRM0BRohpNk6X2COPocf9HvcFI8
 xWajm+nkSsEaQNtXRAj/ku7cLovNgHTJt0KXQyCgxBVol19Gf5davHTe5+pPnsfQ
 e+jdUek4
 =wWgw
 -----END PGP SIGNATURE-----

Merge tag '4.20-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three small fixes: a fix for smb3 direct i/o, a fix for CIFS DFS for
  stable and a minor cifs Kconfig fix"

* tag '4.20-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Avoid returning EBUSY to upper layer VFS
  cifs: Fix separator when building path from dentry
  cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)
2018-12-09 10:15:13 -08:00
Linus Torvalds
fa82dcbf2a dax fixes 4.20-rc6
* Fix the Xarray conversion of fsdax to properly handle
 dax_lock_mapping_entry() in the presense of pmd entries.
 
 * Fix inode destruction racing a new lock request.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJcDLC5AAoJEB7SkWpmfYgC0yAP/2NULGPapIoR2aw7GKPOStHR
 tOMGE8+ZDtpd19oVoEiB3PuhMkiCj5Pkyt2ka9eUXSk3VR/N6EtGwBANFUO+0tEh
 yU8nca2T2G1f+MsZbraWA9zj9aPnfpLt46r7p/AjIB2j1/vyXkYMkXmkXtCvMEUi
 3Q9dVsT53fWncJBlTe/WW84wWQp77VsVafN4/UP75dv8cN9F+u91P1xvUXu2AKus
 RBqjlp6G6xMZ9HcWCQmStdPCi+qbO4k3oTZcohd/DYLb70ZL1kLoEMOjK2/3GnaV
 YMHZGWRAK5jroDZbdXXnJHE+4/opZpSWhW/J1WFEJUSSr7YmZsWhwegmrBlQ5cp3
 V0fZ7LjBWjgtUKsjlmfmu4ccLY87LzVlfIEtJH2+QNiLy/Pl/O0P/Jzg9kHVLEgo
 zph2yIQlx3yshej8EEBPylDJVtYVzOyjLNLx7r3bL6AzQv+6CKqjxtYOiIDwYQsA
 Db1InfeDzAAoH6NYSbqN+yG01Bz7zeCYT7Ch4rYSKcA1i8vUMR6iObI32fC3xJQm
 +TxYmqngrJaU8XOMikIem/qGn4fBpYFULrIdK7lj/WmIxQq8Hp0mqz1ikMIoErzN
 ZXV5RcbbvSSZi5EOrrVKbr2IfIcx+HYo/bIAkRCR69o8bcIZnLPHDky/7gl7GS/5
 sc9A/kysseeF45L2+6QG
 =kUil
 -----END PGP SIGNATURE-----

Merge tag 'dax-fixes-4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull dax fixes from Dan Williams:
 "The last of the known regression fixes and fallout from the Xarray
  conversion of the filesystem-dax implementation.

  On the path to debugging why the dax memory-failure injection test
  started failing after the Xarray conversion a couple more fixes for
  the dax_lock_mapping_entry(), now called dax_lock_page(), surfaced.
  Those plus the bug that started the hunt are now addressed. These
  patches have appeared in a -next release with no issues reported.

  Note the touches to mm/memory-failure.c are just the conversion to the
  new function signature for dax_lock_page().

  Summary:

   - Fix the Xarray conversion of fsdax to properly handle
     dax_lock_mapping_entry() in the presense of pmd entries

   - Fix inode destruction racing a new lock request"

* tag 'dax-fixes-4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix unlock mismatch with updated API
  dax: Don't access a freed inode
  dax: Check page->mapping isn't NULL
2018-12-09 09:54:04 -08:00
Linus Torvalds
f896adc42d Changes since last update:
- Fix broken project quota inode counts
 - Fix incorrect PAGE_MASK/PAGE_SIZE usage
 - Fix incorrect return value in btree verifier
 - Fix WARN_ON remap flags false positive
 - Fix splice read overflows
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAlwGu/sACgkQ+H93GTRK
 tOum2g/5AWN2OMMqbCYru3BSrp4my26/CgGgsLdfR5go+fKvSI8txAm5Wx8r2doP
 aBQ0LuJaKm16bufpFx+LQDKvE/AV8yd3tL58ozPSbpPjdQFpl4DR3N95pURQJVhP
 Yt3tDuPk6ODJ/pKYSbM0GTTyJ5jr+tUlKU6kmAqNzg1W644TWZVV9zFCVU202sj9
 xZ6Auan3yb5wXk2vhgxPgHrVh5ngRm2G+/V8KxCVoWyP/lHUjgEcWJEu+/Jh8xOQ
 6dAYxdfngQqdlXI3dpJDOkFHbqcSrhl8+fQEnp+g0RyWcKPDS+L6wk4Xlkhaorjy
 nDB4GcnjCPHdJ8x/9pUlNmBrlXpAz4oNYqlQcJKssd5q9p+eTBH2drRDc5VDM5KU
 xSHsdIIxQ1YewJ3uHcIbaYBsK+XcrWCtypUTC73GeGkLqS1qKCuKCEnMQOR3czeE
 /Hyq6/eTSt2uG62MAOZGdIW4uaJsLTnXnfDElZ1YsdwtMEzKbYg1Ll2s86vudrRu
 Otyl3EVdXQjtWRxrelA5eexspoJNoZS69D6Haqt8MGc2HJoJGTuparV6YlsEeGoW
 bZFO8JV/Q0WFCa2cWRXVe+D+kx8fyFoDsKY1mR4Vwp5s0jQXp9/rQ81+zVjQ4wB2
 TU53a4+hMLKLW5aNH3ge3yB9ZlHZhEzex6hrlZH3kuqpAM3Yj00=
 =18EP
 -----END PGP SIGNATURE-----

Merge tag 'xfs-4.20-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull xfs fixes from Darrick Wong:
 "Here are hopefully the last set of fixes for 4.20.

  There's a fix for a longstanding statfs reporting problem with project
  quotas, a correction for page cache invalidation behaviors when
  fallocating near EOF, and a fix for a broken metadata verifier return
  code.

  Finally, the most important fix is to the pipe splicing code (aka the
  generic copy_file_range fallback) to avoid pointless short directio
  reads by only asking the filesystem for as much data as there are
  available pages in the pipe buffer. Our previous fix (simulated short
  directio reads because the number of pages didn't match the length of
  the read requested) caused subtle problems on overlayfs, so that part
  is reverted.

  Anyhow, this series passes fstests -g all on xfs and overlay+xfs, and
  has passed 17 billion fsx operations problem-free since I started
  testing

  Summary:

   - Fix broken project quota inode counts

   - Fix incorrect PAGE_MASK/PAGE_SIZE usage

   - Fix incorrect return value in btree verifier

   - Fix WARN_ON remap flags false positive

   - Fix splice read overflows"

* tag 'xfs-4.20-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: partially revert 4721a60109 (simulated directio short read on EFAULT)
  splice: don't read more than available pipe space
  vfs: allow some remap flags to be passed to vfs_clone_file_range
  xfs: fix inverted return from xfs_btree_sblock_verify_crc
  xfs: fix PAGE_MASK usage in xfs_free_file_space
  fs/xfs: fix f_ffree value for statfs when project quota is set
2018-12-08 11:25:02 -08:00
Long Li
6ac79291fb CIFS: Avoid returning EBUSY to upper layer VFS
EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.

This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-12-07 00:59:23 -06:00
Linus Torvalds
7f80c7325b NFS client bugfixes for Linux 4.20
Highlights include:
 
 Stable fixes:
  - Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.
 
 Bugfixes:
  - Fix a regression that causes the RPC receive code to hang
  - Fix call_connect_status() so that it handles tasks that got transmitted
    while queued waiting for the socket lock.
  - Fix a memory leak in call_encode()
  - Fix several other connect races.
  - Fix receive code error handling.
  - Use the discard iterator rather than MSG_TRUNC for compatibility with
    AF_UNIX/AF_LOCAL sockets.
  - nfs: don't dirty kernel pages read by direct-io
  - pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4 data
    servers
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJcCWIOAAoJEA4mA3inWBJc3BsP/i/VXd0ZSxxL8i/++qCR1KGT
 /p0+t2HbrhPzb3jKmuaBe/6T6bLMbpmkwbesA6cHENkaPiOqxPhxLsJlh4o2BHwg
 NcjAbbov/hkakFAHlp69KqiL7DZe8YEqQE8GlUnn+3C3RM3i2TSRQ3AGXUH22P2a
 MY5fqiub2PmEwe2UZR8BzIEQd5w60AzTNXzQb181/+SCTOPdJTKneh0Tw54lD4d6
 vWKhi64cyQxQxshCvrX6IpcNWu9qwm7qDGQ3rDAg0whunve4YGtTz1suRUk888M4
 VfNxA8skFZuaQS/UU6oek2xaeMlSzEoJQXimKLYTEJKoqf7sWxfNLAfqHwnfyo4T
 Yab3cfVRs5KgEltVZyodb9oVQd6KI13hYeT+vXubz2kq1Ode4NJCnzgEefOP0hNV
 ENDal0hqBrfjfVIkpg/wfgRJln/W4Y/U0oPPm50eJJxa0ZKTfftBWo4me5DwCFF9
 0/XhPdFWTvZsYjmSGRC1RsaSrzUvO+wFo3tKQ2lQqf8QP3ix9ZtGQHN+h8RN9SxK
 ti5OxTMsfM3jYg7+yu4yOAQkcCcoaDA37+JztpuUSlMRfNss8uM7cQKsQ4WQf6Nr
 24At5Wr/ib7hVkAQ5oB98UWh5q1ZLzmmHhzsf8KacTSNcfjgu0H0DmKtm3CfThFK
 xfTHotzM3IqbUXRZQ7++
 =M/mt
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "This is mainly fallout from the updates to the SUNRPC code that is
  being triggered from less common combinations of NFS mount options.

  Highlights include:

  Stable fixes:
   - Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.

  Bugfixes:
   - Fix a regression that causes the RPC receive code to hang
   - Fix call_connect_status() so that it handles tasks that got
     transmitted while queued waiting for the socket lock.
   - Fix a memory leak in call_encode()
   - Fix several other connect races.
   - Fix receive code error handling.
   - Use the discard iterator rather than MSG_TRUNC for compatibility
     with AF_UNIX/AF_LOCAL sockets.
   - nfs: don't dirty kernel pages read by direct-io
   - pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4
     data servers"

* tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Don't force a redundant disconnection in xs_read_stream()
  SUNRPC: Fix up socket polling
  SUNRPC: Use the discard iterator rather than MSG_TRUNC
  SUNRPC: Treat EFAULT as a truncated message in xs_read_stream_request()
  SUNRPC: Fix up handling of the XDRBUF_SPARSE_PAGES flag
  SUNRPC: Fix RPC receive hangs
  SUNRPC: Fix a potential race in xprt_connect()
  SUNRPC: Fix a memory leak in call_encode()
  SUNRPC: Fix leak of krb5p encode pages
  SUNRPC: call_connect_status() must handle tasks that got transmitted
  nfs: don't dirty kernel pages read by direct-io
  flexfiles: enforce per-mirror stateid only for v4 DSes
2018-12-06 18:57:04 -08:00
Paulo Alcantara
c988de29ca cifs: Fix separator when building path from dentry
Make sure to use the CIFS_DIR_SEP(cifs_sb) as path separator for
prefixpath too. Fixes a bug with smb1 UNIX extensions.

Fixes: a6b5058faf ("fs/cifs: make share unaccessible at root level mountable")
Signed-off-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
2018-12-06 02:20:17 -06:00
Steve French
6e785302da cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)
Missing a dependency.  Shouldn't show cifs posix extensions
in Kconfig if CONFIG_CIFS_ALLOW_INSECURE_DIALECTS (ie SMB1
protocol) is disabled.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-12-06 02:20:14 -06:00
Linus Torvalds
d089709045 for-4.20-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAlwH0k8ACgkQxWXV+ddt
 WDtmVg/+Kgvk7laQI9bLEr1/30eG1JfBUMHcVE1F8+g99l28m1Yihjd21j9norVd
 YexBz53jgKou+zV+37CKWBYT1uDPq7CIoxctkdE2j9U0s+RmsqDrhech0dsBsfMR
 jo9VnHJFuJSxGMhjfGnFV+wMtAr4q5aQptNGBl+hR1MvMneroktFv+0WiLmp0Vhj
 +6Iq9WAClJYpgk//cI7nhKkscdzWwRyN3V9RUtdNeYklk1D7l1WprlaPzw22WA9u
 VjQVMICjEaJeIixIwT/D8lz05QgjKlqy1z6faYG5JuJxoYQikuNv/xe2dhZVm35A
 aNsBR0byf3zzuXKQZAlvXJ6/gYPvep+KI7epPyBOdycaqoZza7rQ+/MkSAgQ77Vk
 yBnQuhqiw9Srjh6LDWFkNclVln2wymRKd1SqpZmFPRZre/8L+DU+I8RRaeS2/WcE
 M2k+awRD0oVofbB+hxkFIoR+I1Ggkp2rxQlTT/41tGx0geWC3AGX+TlKSW6ZM5HD
 lRmRXIsVocfighKEnI3Zy7ecZuwCI4/4D6+PQtyhCJb3tDigZ/a4UEYdSVucG8CG
 SuQ5YMn+MyyKT0wH8xkGKDGT15YZ+u9Q/BmPHZRL6sSouFpiCQHA5miD1YA+t1d9
 qMjH6Ycz46Y3j2M0BDfDcm714zoD5/bgeSy5SPC3Zh5lQCGpeIk=
 =VW/F
 -----END PGP SIGNATURE-----

Merge tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "A patch in 4.19 introduced a sanity check that was too strict and a
  filesystem cannot be mounted.

  This happens for filesystems with more than 10 devices and has been
  reported by a few users so we need the fix to propagate to stable"

* tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
2018-12-05 09:58:17 -08:00
Matthew Wilcox
27359fd6e5 dax: Fix unlock mismatch with updated API
Internal to dax_unlock_mapping_entry(), dax_unlock_entry() is used to
store a replacement entry in the Xarray at the given xas-index with the
DAX_LOCKED bit clear. When called, dax_unlock_entry() expects the unlocked
value of the entry relative to the current Xarray state to be specified.

In most contexts dax_unlock_entry() is operating in the same scope as
the matched dax_lock_entry(). However, in the dax_unlock_mapping_entry()
case the implementation needs to recall the original entry. In the case
where the original entry is a 'pmd' entry it is possible that the pfn
performed to do the lookup is misaligned to the value retrieved in the
Xarray.

Change the api to return the unlock cookie from dax_lock_page() and pass
it to dax_unlock_page(). This fixes a bug where dax_unlock_page() was
assuming that the page was PMD-aligned if the entry was a PMD entry with
signatures like:

 WARNING: CPU: 38 PID: 1396 at fs/dax.c:340 dax_insert_entry+0x2b2/0x2d0
 RIP: 0010:dax_insert_entry+0x2b2/0x2d0
 [..]
 Call Trace:
  dax_iomap_pte_fault.isra.41+0x791/0xde0
  ext4_dax_huge_fault+0x16f/0x1f0
  ? up_read+0x1c/0xa0
  __do_fault+0x1f/0x160
  __handle_mm_fault+0x1033/0x1490
  handle_mm_fault+0x18b/0x3d0

Link: https://lkml.kernel.org/r/20181130154902.GL10377@bombadil.infradead.org
Fixes: 9f32d22130 ("dax: Convert dax_lock_mapping_entry to XArray")
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-04 21:32:00 -08:00
Darrick J. Wong
8f67b5adc0 iomap: partially revert 4721a60109 (simulated directio short read on EFAULT)
In commit 4721a60109, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read.  This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.

In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads.  This causes infinite
splice() loops and assertion failures on generic/095 on overlayfs
because xfs only permit total success or total failure of a directio
operation.  The underlying issue in the pipe splice code has now been
fixed by changing the pipe splice loop to avoid avoid reading more data
than there is space in the pipe.

Therefore, it's no longer necessary to simulate the short directio, so
remove the hack from iomap.

Fixes: 4721a60109 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 09:40:02 -08:00
Darrick J. Wong
1761444557 splice: don't read more than available pipe space
In commit 4721a60109, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read.  This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.

In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads.

The brokenness is compounded by splice_direct_to_actor immediately
bailing on do_splice_to returning <= 0 without ever calling ->actor
(which empties out the pipe), so if userspace calls back we'll EFAULT
again on the full pipe, and nothing ever gets copied.

Therefore, teach splice_direct_to_actor to clamp its requests to the
amount of free space in the pipe and remove the simulated short read
from the iomap directio code.

Fixes: 4721a60109 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 08:50:49 -08:00
Darrick J. Wong
6744557b53 vfs: allow some remap flags to be passed to vfs_clone_file_range
In overlayfs, ovl_remap_file_range calls vfs_clone_file_range on the
lower filesystem's inode, passing through whatever remap flags it got
from its caller.  Since vfs_copy_file_range first tries a filesystem's
remap function with REMAP_FILE_CAN_SHORTEN, this can get passed through
to the second vfs_copy_file_range call, and this isn't an issue.
Change the WARN_ON to look only for the DEDUP flag.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-12-04 08:50:49 -08:00
Eric Sandeen
7d048df4e9 xfs: fix inverted return from xfs_btree_sblock_verify_crc
xfs_btree_sblock_verify_crc is a bool so should not be returning
a failaddr_t; worse, if xfs_log_check_lsn fails it returns
__this_address which looks like a boolean true (i.e. success)
to the caller.

(interestingly xfs_btree_lblock_verify_crc doesn't have the issue)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-12-04 08:50:49 -08:00
Darrick J. Wong
a579121f94 xfs: fix PAGE_MASK usage in xfs_free_file_space
In commit e53c4b598, I *tried* to teach xfs to force writeback when we
fzero/fpunch right up to EOF so that if EOF is in the middle of a page,
the post-EOF part of the page gets zeroed before we return to userspace.
Unfortunately, I missed the part where PAGE_MASK is ~(PAGE_SIZE - 1),
which means that we totally fail to zero if we're fpunching and EOF is
within the first page.  Worse yet, the same PAGE_MASK thinko plagues the
filemap_write_and_wait_range call, so we'd initiate writeback of the
entire file, which (mostly) masked the thinko.

Drop the tricky PAGE_MASK and replace it with correct usage of PAGE_SIZE
and the proper rounding macros.

Fixes: e53c4b598 ("xfs: ensure post-EOF zeroing happens after zeroing part of a file")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-12-04 08:50:49 -08:00
Rafael J. Wysocki
a72173ecfc Revert "exec: make de_thread() freezable"
Revert commit c22397888f "exec: make de_thread() freezable" as
requested by Ingo Molnar:

"So there's a new regression in v4.20-rc4, my desktop produces this
lockdep splat:

[ 1772.588771] WARNING: pkexec/4633 still has locks held!
[ 1772.588773] 4.20.0-rc4-custom-00213-g93a49841322b #1 Not tainted
[ 1772.588775] ------------------------------------
[ 1772.588776] 1 lock held by pkexec/4633:
[ 1772.588778]  #0: 00000000ed85fbf8 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x2a/0x70
[ 1772.588786] stack backtrace:
[ 1772.588789] CPU: 7 PID: 4633 Comm: pkexec Not tainted 4.20.0-rc4-custom-00213-g93a49841322b #1
[ 1772.588792] Call Trace:
[ 1772.588800]  dump_stack+0x85/0xcb
[ 1772.588803]  flush_old_exec+0x116/0x890
[ 1772.588807]  ? load_elf_phdrs+0x72/0xb0
[ 1772.588809]  load_elf_binary+0x291/0x1620
[ 1772.588815]  ? sched_clock+0x5/0x10
[ 1772.588817]  ? search_binary_handler+0x6d/0x240
[ 1772.588820]  search_binary_handler+0x80/0x240
[ 1772.588823]  load_script+0x201/0x220
[ 1772.588825]  search_binary_handler+0x80/0x240
[ 1772.588828]  __do_execve_file.isra.32+0x7d2/0xa60
[ 1772.588832]  ? strncpy_from_user+0x40/0x180
[ 1772.588835]  __x64_sys_execve+0x34/0x40
[ 1772.588838]  do_syscall_64+0x60/0x1c0

The warning gets triggered by an ancient lockdep check in the freezer:

(gdb) list *0xffffffff812ece06
0xffffffff812ece06 is in flush_old_exec (./include/linux/freezer.h:57).
52	 * DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION
53	 * If try_to_freeze causes a lockdep warning it means the caller may deadlock
54	 */
55	static inline bool try_to_freeze_unsafe(void)
56	{
57		might_sleep();
58		if (likely(!freezing(current)))
59			return false;
60		return __refrigerator(false);
61	}

I reviewed the ->cred_guard_mutex code, and the mutex is held across all
of exec() - and we always did this.

But there's this recent -rc4 commit:

> Chanho Min (1):
>       exec: make de_thread() freezable

  c22397888f: exec: make de_thread() freezable

I believe this commit is bogus, you cannot call try_to_freeze() from
de_thread(), because it's holding the ->cred_guard_mutex."

Reported-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-04 16:04:20 +01:00
Qu Wenruo
10950929e9 btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable
[BUG]
A completely valid btrfs will refuse to mount, with error message like:
  BTRFS critical (device sdb2): corrupt leaf: root=2 block=239681536 slot=172 \
    bg_start=12018974720 bg_len=10888413184, invalid block group size, \
    have 10888413184 expect (0, 10737418240]

This has been reported several times as the 4.19 kernel is now being
used. The filesystem refuses to mount, but is otherwise ok and booting
4.18 is a workaround.

Btrfs check returns no error, and all kernels used on this fs is later
than 2011, which should all have the 10G size limit commit.

[CAUSE]
For a 12 devices btrfs, we could allocate a chunk larger than 10G due to
stripe stripe bump up.

__btrfs_alloc_chunk()
|- max_stripe_size = 1G
|- max_chunk_size = 10G
|- data_stripe = 11
|- if (1G * 11 > 10G) {
       stripe_size = 976128930;
       stripe_size = round_up(976128930, SZ_16M) = 989855744

However the final stripe_size (989855744) * 11 = 10888413184, which is
still larger than 10G.

[FIX]
For the comprehensive check, we need to do the full check at chunk read
time, and rely on bg <-> chunk mapping to do the check.

We could just skip the length check for now.

Fixes: fce466eab7 ("btrfs: tree-checker: Verify block_group_item")
Cc: stable@vger.kernel.org # v4.19+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-12-04 15:05:30 +01:00
Miklos Szeredi
ec7ba118b9 Revert "ovl: relax permission checking on underlying layers"
This reverts commit 007ea44892.

The commit broke some selinux-testsuite cases, and it looks like there's no
straightforward fix keeping the direction of this patch, so revert for now.

The original patch was trying to fix the consistency of permission checks, and
not an observed bug.  So reverting should be safe.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-04 11:31:30 +01:00
Miklos Szeredi
d233c7dd16 fuse: fix revalidation of attributes for permission check
fuse_invalidate_attr() now sets fi->inval_mask instead of fi->i_time, hence
we need to check the inval mask in fuse_permission() as well.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 2f1e81965f ("fuse: allow fine grained attr cache invaldation")
2018-12-03 10:14:43 +01:00
Miklos Szeredi
a9c2d1e82f fuse: fix fsync on directory
Commit ab2257e994 ("fuse: reduce size of struct fuse_inode") moved parts
of fields related to writeback on regular file and to directory caching
into a union.  However fuse_fsync_common() called from fuse_dir_fsync()
touches some writeback related fields, resulting in a crash.

Move writeback related parts from fuse_fsync_common() to fuse_fysnc().

Reported-by: Brett Girton <btgirton@gmail.com>
Tested-by: Brett Girton <btgirton@gmail.com>
Fixes: ab2257e994 ("fuse: reduce size of struct fuse_inode")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-12-03 10:14:43 +01:00
Dave Kleikamp
ad3cba223a nfs: don't dirty kernel pages read by direct-io
When we use direct_IO with an NFS backing store, we can trigger a
WARNING in __set_page_dirty(), as below, since we're dirtying the page
unnecessarily in nfs_direct_read_completion().

To fix, replicate the logic in commit 53cbf3b157 ("fs: direct-io:
don't dirtying pages for ITER_BVEC/ITER_KVEC direct read").

Other filesystems that implement direct_IO handle this; most use
blockdev_direct_IO(). ceph and cifs have similar logic.

mount 127.0.0.1:/export /nfs
dd if=/dev/zero of=/nfs/image bs=1M count=200
losetup --direct-io=on -f /nfs/image
mkfs.btrfs /dev/loop0
mount -t btrfs /dev/loop0 /mnt/

kernel: WARNING: CPU: 0 PID: 8067 at fs/buffer.c:580 __set_page_dirty+0xaf/0xd0
kernel: Modules linked in: loop(E) nfsv3(E) rpcsec_gss_krb5(E) nfsv4(E) dns_resolver(E) nfs(E) fscache(E) nfsd(E) auth_rpcgss(E) nfs_acl(E) lockd(E) grace(E) fuse(E) tun(E) ip6t_rpfilter(E) ipt_REJECT(E) nf_
kernel:  snd_seq(E) snd_seq_device(E) snd_pcm(E) video(E) snd_timer(E) snd(E) soundcore(E) ip_tables(E) xfs(E) libcrc32c(E) sd_mod(E) sr_mod(E) cdrom(E) ata_generic(E) pata_acpi(E) crc32c_intel(E) ahci(E) li
kernel: CPU: 0 PID: 8067 Comm: kworker/0:2 Tainted: G            E     4.20.0-rc1.master.20181111.ol7.x86_64 #1
kernel: Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
kernel: Workqueue: nfsiod rpc_async_release [sunrpc]
kernel: RIP: 0010:__set_page_dirty+0xaf/0xd0
kernel: Code: c3 48 8b 02 f6 c4 04 74 d4 48 89 df e8 ba 05 f7 ff 48 89 c6 eb cb 48 8b 43 08 a8 01 75 1f 48 89 d8 48 8b 00 a8 04 74 02 eb 87 <0f> 0b eb 83 48 83 e8 01 eb 9f 48 83 ea 01 0f 1f 00 eb 8b 48 83 e8
kernel: RSP: 0000:ffffc1c8825b7d78 EFLAGS: 00013046
kernel: RAX: 000fffffc0020089 RBX: fffff2b603308b80 RCX: 0000000000000001
kernel: RDX: 0000000000000001 RSI: ffff9d11478115c8 RDI: ffff9d11478115d0
kernel: RBP: ffffc1c8825b7da0 R08: 0000646f6973666e R09: 8080808080808080
kernel: R10: 0000000000000001 R11: 0000000000000000 R12: ffff9d11478115d0
kernel: R13: ffff9d11478115c8 R14: 0000000000003246 R15: 0000000000000001
kernel: FS:  0000000000000000(0000) GS:ffff9d115ba00000(0000) knlGS:0000000000000000
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 00007f408686f640 CR3: 0000000104d8e004 CR4: 00000000000606f0
kernel: DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
kernel: DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
kernel: Call Trace:
kernel:  __set_page_dirty_buffers+0xb6/0x110
kernel:  set_page_dirty+0x52/0xb0
kernel:  nfs_direct_read_completion+0xc4/0x120 [nfs]
kernel:  nfs_pgio_release+0x10/0x20 [nfs]
kernel:  rpc_free_task+0x30/0x70 [sunrpc]
kernel:  rpc_async_release+0x12/0x20 [sunrpc]
kernel:  process_one_work+0x174/0x390
kernel:  worker_thread+0x4f/0x3e0
kernel:  kthread+0x102/0x140
kernel:  ? drain_workqueue+0x130/0x130
kernel:  ? kthread_stop+0x110/0x110
kernel:  ret_from_fork+0x35/0x40
kernel: ---[ end trace 01341980905412c9 ]---

Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>

[forward-ported to v4.20]
Signed-off-by: Calum Mackay <calum.mackay@oracle.com>
Reviewed-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-12-02 09:43:56 -05:00
Tigran Mkrtchyan
320f35b7bf flexfiles: enforce per-mirror stateid only for v4 DSes
Since commit bb21ce0ad2 we always enforce per-mirror stateid.
However, this makes sense only for v4+ servers.

Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-12-02 09:43:56 -05:00
Linus Torvalds
880584176e for-linus-20181201
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAlwC1c4QHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgppxmD/4pqn8REEh/QUXWhCJbOXLLLxfQju7Uxs/v
 j2Bc6W/e7Z9jvKAs06IIhaV6SxBrM0oUebf/hJY0E/kTSHiNPJqx/X3W9hFYOo+p
 EJau3vavOrxVzgq5zt8S/i//HeanT+H37nE9WDqSRKXTta8JFDw+DoysepILTUvN
 WGDjuplPcurwmf2W1qES+5vNy/Jpln9ErNuqPBSjc6shozQ8WAzvuupVs+uZEpeK
 +gqrx0pJYrtoU+pSUK+Bt6bSzzp8Z0qHGIVMAabNULbz43qblK0ILRE+qLFbFwsB
 62EMMtX9b2Lsvqpoe2cQ+deQlUalsGVmpyE+7GP/evZbVmtD/NoH6cJQ/dA/tFtw
 cluL3rWBJKB5OZ1yatDE2/rUYsGo5FzqMUz/tIWSf2FdZcLfhRNLka7DueSA6NQe
 wtLJU9GrME67+t+PqncjDxoyQYma4oynAcc5dfqlBQv5OP7HDf4TP28g8FdkHjcy
 fEXAp58516YZiCpoWZf6dPR9fUQ0A1eF+qxHnUacy5tHN4AKPrccU3+k+0WStFNf
 qaOPkj4kWtv17d2DO4UoqAtBqFO16QCYSsa5+drpDeTOq9QgGqA6O+sGngN0LsxS
 F7x3msgBIkgEFYFtpuMBXnamdooiZMKrzI0Ctn7PK8b5Qx1OgRNCZcTQD4uql1Fj
 L6R/6Ynibg==
 =lMlT
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-20181201' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:

 - Single range elevator discard merge fix, that caused crashes (Ming)

 - Fix for a regression in O_DIRECT, where we could potentially lose the
   error value (Maximilian Heyne)

 - NVMe pull request from Christoph, with little fixes all over the map
   for NVMe.

* tag 'for-linus-20181201' of git://git.kernel.dk/linux-block:
  block: fix single range discard merge
  nvme-rdma: fix double freeing of async event data
  nvme: flush namespace scanning work just before removing namespaces
  nvme: warn when finding multi-port subsystems without multipathing enabled
  fs: fix lost error code in dio_complete
  nvme-pci: fix surprise removal
  nvme-fc: initialize nvme_req(rq)->ctrl after calling __nvme_fc_init_request()
  nvme: Free ctrl device name on init failure
2018-12-01 11:36:32 -08:00
Linus Torvalds
d8f190ee83 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "31 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (31 commits)
  ocfs2: fix potential use after free
  mm/khugepaged: fix the xas_create_range() error path
  mm/khugepaged: collapse_shmem() do not crash on Compound
  mm/khugepaged: collapse_shmem() without freezing new_page
  mm/khugepaged: minor reorderings in collapse_shmem()
  mm/khugepaged: collapse_shmem() remember to clear holes
  mm/khugepaged: fix crashes due to misaccounted holes
  mm/khugepaged: collapse_shmem() stop if punched or truncated
  mm/huge_memory: fix lockdep complaint on 32-bit i_size_read()
  mm/huge_memory: splitting set mapping+index before unfreeze
  mm/huge_memory: rename freeze_page() to unmap_page()
  initramfs: clean old path before creating a hardlink
  kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace
  psi: make disabling/enabling easier for vendor kernels
  proc: fixup map_files test on arm
  debugobjects: avoid recursive calls with kmemleak
  userfaultfd: shmem: UFFDIO_COPY: set the page dirty if VM_WRITE is not set
  userfaultfd: shmem: add i_size checks
  userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
  userfaultfd: shmem: allocate anonymous memory for MAP_PRIVATE shmem
  ...
2018-11-30 18:45:49 -08:00
Linus Torvalds
fd3b3e0ec5 FS-Cache fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXAFfSPu3V2unywtrAQKPQRAAiHDs2d35Kc2qkTFLwGiP+wr+3+7Cyz7A
 hrWAvR7Oe7nBFVPmp6pwEnpBhf3mPsWlQpw3ZKZPo4fDQyRX+mDFC+2C7hkU1Q/J
 BkjTG4vYn1jiQGlL3SD1PfUxcWfwzoK4cz+V3hnFY5y0dsKiBZBR1Lw5G+UkaCnD
 4VaC3VAG56Vh14o5qSF3TWLZFyZ+JN6YA/M/DnwRPl8y4jnj1tJLs1DjdpEcWv6r
 15FKb2FRYaC7MRehpXd22JX6fv5ii2xazU3IfLucBrb4Vj+wAJrBY4wA3x/CFkAa
 as1VmxLkgoJEWa3M71tQOJBC8+QqkRb++PRUI3aadt2H4hXHfx3AmBuKkVroeS8o
 0BDhWGiTW4AqXUajkQcTc/mKV2x6h83V3DLyBRL1iC3+7qaBVhPNtxW+v6ln0Ce1
 FRG2I9LZp+RtWrVVyIPsa03V2V5OD7PTIBXK6TYtuqL+3uu7TNNc+UySvqDHWLL+
 Zo2ogpq//kZbjMdntNVhDEj12LW3zG05dtNuFEeJeuPM28yiXXtoWDmI49RAUQ4v
 RN6SwEXnKWehwG+YITYavV6gfHWlXdZ7grgCMHyViF/s9khBp7AGxbRzR0JXgXqL
 ko1Ojpbq2mdvjwGFQfde4MAqAxM3FPxdxGVLrgi+lgGTsEKv6IzrTo28teyAM81O
 D6cH0ldY90w=
 =6y+F
 -----END PGP SIGNATURE-----

Merge tag 'fscache-fixes-20181130' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull fscache and cachefiles fixes from David Howells:
 "Misc fixes:

   - Fix an assertion failure at fs/cachefiles/xattr.c:138 caused by a
     race between a cache object lookup failing and someone attempting
     to reenable that object, thereby triggering an update of the
     object's attributes.

   - Fix an assertion failure at fs/fscache/operation.c:449 caused by a
     split atomic subtract and atomic read that allows a race to happen.

   - Fix a leak of backing pages when simultaneously reading the same
     page from the same object from two or more threads.

   - Fix a hang due to a race between a cache object being discarded and
     the corresponding cookie being reenabled.

  There are also some minor cleanups:

   - Cast an enum value to a different enum type to prevent clang from
     generating a warning. This shouldn't cause any sort of change in
     the emitted code.

   - Use ktime_get_real_seconds() instead of get_seconds(). This is just
     used to uniquify a filename for an object to be placed in the
     graveyard. Objects placed there are deleted by cachfilesd in
     userspace immediately thereafter.

   - Remove an initialised, but otherwise unused variable. This should
     have been entirely optimised away anyway"

* tag 'fscache-fixes-20181130' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  fscache, cachefiles: remove redundant variable 'cache'
  cachefiles: avoid deprecated get_seconds()
  cachefiles: Explicitly cast enumerated type in put_object
  fscache: fix race between enablement and dropping of object
  cachefiles: Fix page leak in cachefiles_read_backing_file while vmscan is active
  fscache: Fix race in fscache_op_complete() due to split atomic_sub & read
  cachefiles: Fix an assertion failure when trying to update a failed object
2018-11-30 18:32:33 -08:00
Pan Bian
164f7e5867 ocfs2: fix potential use after free
ocfs2_get_dentry() calls iput(inode) to drop the reference count of
inode, and if the reference count hits 0, inode is freed.  However, in
this function, it then reads inode->i_generation, which may result in a
use after free bug.  Move the put operation later.

Link: http://lkml.kernel.org/r/1543109237-110227-1-git-send-email-bianpan2016@163.com
Fixes: 781f200cb7a("ocfs2: Remove masklog ML_EXPORT.")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
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 <ge.changwei@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-30 14:56:15 -08:00