Now that sparse has been fixed, it spotted a couple recent minor
endian errors (and removed one additional sparse warning).

Thanks to Luc Van Oostenryck for his help fixing sparse.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

In commit 4ed28639 ("fs, elf: drop MAP_FIXED usage from elf_map") we
changed elf to use MAP_FIXED_NOREPLACE instead of MAP_FIXED for the
executable mappings.

Then, people reported that it broke some binaries that had overlapping
segments from the same file, and commit ad55eac7 ("elf: enforce
MAP_FIXED on overlaying elf segments") re-instated MAP_FIXED for some
overlaying elf segment cases.  But only some - despite the summary line
of that commit, it only did it when it also does a temporary brk vma for
one obvious overlapping case.

Now Russell King reports another overlapping case with old 32-bit x86
binaries, which doesn't trigger that limited case.  End result: we had
better just drop MAP_FIXED_NOREPLACE entirely, and go back to MAP_FIXED.

Yes, it's a sign of old binaries generated with old tool-chains, but we
do pride ourselves on not breaking existing setups.

This still leaves MAP_FIXED_NOREPLACE in place for the load_elf_interp()
and the old load_elf_library() use-cases, because nobody has reported
breakage for those. Yet.

Note that in all the cases seen so far, the overlapping elf sections
seem to be just re-mapping of the same executable with different section
attributes.  We could possibly introduce a new MAP_FIXED_NOFILECHANGE
flag or similar, which acts like NOREPLACE, but allows just remapping
the same executable file using different protection flags.

It's not clear that would make a huge difference to anything, but if
people really hate that "elf remaps over previous maps" behavior, maybe
at least a more limited form of remapping would alleviate some concerns.

Alternatively, we should take a look at our elf_map() logic to see if we
end up not mapping things properly the first time.

In the meantime, this is the minimal "don't do that then" patch while
people hopefully think about it more.
Reported-by: NRussell King <linux@armlinux.org.uk>
Fixes: 4ed28639 ("fs, elf: drop MAP_FIXED usage from elf_map")
Fixes: ad55eac7 ("elf: enforce  MAP_FIXED on overlaying elf segments")
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This has been discussed several times, and now filesystem people are
talking about doing it individually at the filesystem layer, so head
that off at the pass and just do it in getdents{64}().

This is partially based on a patch by Jann Horn, but checks for NUL
bytes as well, and somewhat simplified.

There's also commentary about how it might be better if invalid names
due to filesystem corruption don't cause an immediate failure, but only
an error at the end of the readdir(), so that people can still see the
filenames that are ok.

There's also been discussion about just how much POSIX strictly speaking
requires this since it's about filesystem corruption.  It's really more
"protect user space from bad behavior" as pointed out by Jann.  But
since Eric Biederman looked up the POSIX wording, here it is for context:

 "From readdir:

   The readdir() function shall return a pointer to a structure
   representing the directory entry at the current position in the
   directory stream specified by the argument dirp, and position the
   directory stream at the next entry. It shall return a null pointer
   upon reaching the end of the directory stream. The structure dirent
   defined in the <dirent.h> header describes a directory entry.

  From definitions:

   3.129 Directory Entry (or Link)

   An object that associates a filename with a file. Several directory
   entries can associate names with the same file.

  ...

   3.169 Filename

   A name consisting of 1 to {NAME_MAX} bytes used to name a file. The
   characters composing the name may be selected from the set of all
   character values excluding the slash character and the null byte. The
   filenames dot and dot-dot have special meaning. A filename is
   sometimes referred to as a 'pathname component'."

Note that I didn't bother adding the checks to any legacy interfaces
that nobody uses.

Also note that if this ends up being noticeable as a performance
regression, we can fix that to do a much more optimized model that
checks for both NUL and '/' at the same time one word at a time.

We haven't really tended to optimize 'memchr()', and it only checks for
one pattern at a time anyway, and we really _should_ check for NUL too
(but see the comment about "soft errors" in the code about why it
currently only checks for '/')

See the CONFIG_DCACHE_WORD_ACCESS case of hash_name() for how the name
lookup code looks for pathname terminating characters in parallel.

Link: https://lore.kernel.org/lkml/20190118161440.220134-2-jannh@google.com/
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We really should avoid the "__{get,put}_user()" functions entirely,
because they can easily be mis-used and the original intent of being
used for simple direct user accesses no longer holds in a post-SMAP/PAN
world.

Manually optimizing away the user access range check makes no sense any
more, when the range check is generally much cheaper than the "enable
user accesses" code that the __{get,put}_user() functions still need.

So instead of __put_user(), use the unsafe_put_user() interface with
user_access_{begin,end}() that really does generate better code these
days, and which is generally a nicer interface.  Under some loads, the
multiple user writes that filldir() does are actually quite noticeable.

This also makes the dirent name copy use unsafe_put_user() with a couple
of macros.  We do not want to make function calls with SMAP/PAN
disabled, and the code this generates is quite good when the
architecture uses "asm goto" for unsafe_put_user() like x86 does.

Note that this doesn't bother with the legacy cases.  Nobody should use
them anyway, so performance doesn't really matter there.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Today, put_compat_statfs64() disallows nearly any field value over
2^32 if f_bsize is only 32 bits, but that makes no sense.
compat_statfs64 is there for the explicit purpose of providing 64-bit
fields for f_files, f_ffree, etc.  And f_bsize is always only 32 bits.

As a result, 32-bit userspace gets -EOVERFLOW for i.e.  large file
counts even with -D_FILE_OFFSET_BITS=64 set.

In reality, only f_bsize and f_frsize can legitimately overflow
(fields like f_type and f_namelen should never be large), so test
only those fields.

This bug was discussed at length some time ago, and this is the proposal
Al suggested at https://lkml.org/lkml/2018/8/6/640.  It seemed to get
dropped amid the discussion of other related changes, but this
part seems obviously correct on its own, so I've picked it up and
sent it, for expediency.

Fixes: 64d2ab32 ("vfs: fix put_compat_statfs64() does not handle errors")
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All system calls use struct __kernel_timespec instead of the old struct
timespec, but this one was just added with the old-style ABI. Change it
now to enforce the use of __kernel_timespec, avoiding ABI confusion and
the need for compat handlers on 32-bit architectures.

Any user space caller will have to use __kernel_timespec now, but this
is unambiguous and works for any C library regardless of the time_t
definition. A nicer way to specify the timeout would have been a less
ambiguous 64-bit nanosecond value, but I suppose it's too late now to
change that as this would impact both 32-bit and 64-bit users.

Fixes: 5262f567 ("io_uring: IORING_OP_TIMEOUT support")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Fix a recent cleanup patch. noio (bypass) chain is
handled asynchronously against submit chain, therefore
inplace I/O or pagevec cannot be applied to such pages.
Add detailed comment for this as well.

Fixes: 97e86a85 ("staging: erofs: tidy up decompression frontend")
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20190922100434.229340-1-gaoxiang25@huawei.comSigned-off-by: NGao Xiang <gaoxiang25@huawei.com>

After doing more drop_caches stress test on
our products, I found the mistake introduced by
a very recent cleanup [1].

The current rule is that "erofs_get_meta_page"
should be returned with page locked (although
it's mostly unnecessary for read-only fs after
pages are PG_uptodate), but a fix should be
done for this.

[1] https://lore.kernel.org/r/20190904020912.63925-26-gaoxiang25@huawei.com
Fixes: 618f40ea ("erofs: use read_cache_page_gfp for erofs_get_meta_page")
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20190921184355.149928-1-gaoxiang25@huawei.comSigned-off-by: NGao Xiang <gaoxiang25@huawei.com>

In case of error, the function read_mapping_page() returns
ERR_PTR() not NULL. The NULL test in the return value check
should be replaced with IS_ERR().

Fixes: fe7c2423 ("erofs: use read_mapping_page instead of sb_bread")
Reviewed-by: NGao Xiang <gaoxiang25@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Link: https://lore.kernel.org/r/20190918083033.47780-1-weiyongjun1@huawei.comSigned-off-by: NGao Xiang <gaoxiang25@huawei.com>

This reverts commit 72dbcf72.

Instead of waiting forever for entropy that may just not happen, we now
try to actively generate entropy when required, and are thus hopefully
avoiding the problem that caused the nice ext4 IO pattern fix to be
reverted.

So revert the revert.

Cc: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

[BUG]
The following script can cause btrfs qgroup data space leak:

  mkfs.btrfs -f $dev
  mount $dev -o nospace_cache $mnt

  btrfs subv create $mnt/subv
  btrfs quota en $mnt
  btrfs quota rescan -w $mnt
  btrfs qgroup limit 128m $mnt/subv

  for (( i = 0; i < 3; i++)); do
          # Create 3 64M holes for latter fallocate to fail
          truncate -s 192m $mnt/subv/file
          xfs_io -c "pwrite 64m 4k" $mnt/subv/file > /dev/null
          xfs_io -c "pwrite 128m 4k" $mnt/subv/file > /dev/null
          sync

          # it's supposed to fail, and each failure will leak at least 64M
          # data space
          xfs_io -f -c "falloc 0 192m" $mnt/subv/file &> /dev/null
          rm $mnt/subv/file
          sync
  done

  # Shouldn't fail after we removed the file
  xfs_io -f -c "falloc 0 64m" $mnt/subv/file

[CAUSE]
Btrfs qgroup data reserve code allow multiple reservations to happen on
a single extent_changeset:
E.g:
	btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_1M);
	btrfs_qgroup_reserve_data(inode, &data_reserved, SZ_1M, SZ_2M);
	btrfs_qgroup_reserve_data(inode, &data_reserved, 0, SZ_4M);

Btrfs qgroup code has its internal tracking to make sure we don't
double-reserve in above example.

The only pattern utilizing this feature is in the main while loop of
btrfs_fallocate() function.

However btrfs_qgroup_reserve_data()'s error handling has a bug in that
on error it clears all ranges in the io_tree with EXTENT_QGROUP_RESERVED
flag but doesn't free previously reserved bytes.

This bug has a two fold effect:
- Clearing EXTENT_QGROUP_RESERVED ranges
  This is the correct behavior, but it prevents
  btrfs_qgroup_check_reserved_leak() to catch the leakage as the
  detector is purely EXTENT_QGROUP_RESERVED flag based.

- Leak the previously reserved data bytes.

The bug manifests when N calls to btrfs_qgroup_reserve_data are made and
the last one fails, leaking space reserved in the previous ones.

[FIX]
Also free previously reserved data bytes when btrfs_qgroup_reserve_data
fails.

Fixes: 52472553 ("btrfs: qgroup: Introduce btrfs_qgroup_reserve_data function")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: NQu Wenruo <wqu@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

[BUG]
Under the following case with qgroup enabled, if some error happened
after we have reserved delalloc space, then in error handling path, we
could cause qgroup data space leakage:

From btrfs_truncate_block() in inode.c:

	ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
					   block_start, blocksize);
	if (ret)
		goto out;

 again:
	page = find_or_create_page(mapping, index, mask);
	if (!page) {
		btrfs_delalloc_release_space(inode, data_reserved,
					     block_start, blocksize, true);
		btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, true);
		ret = -ENOMEM;
		goto out;
	}

[CAUSE]
In the above case, btrfs_delalloc_reserve_space() will call
btrfs_qgroup_reserve_data() and mark the io_tree range with
EXTENT_QGROUP_RESERVED flag.

In the error handling path, we have the following call stack:
btrfs_delalloc_release_space()
|- btrfs_free_reserved_data_space()
   |- btrsf_qgroup_free_data()
      |- __btrfs_qgroup_release_data(reserved=@reserved, free=1)
         |- qgroup_free_reserved_data(reserved=@reserved)
            |- clear_record_extent_bits();
            |- freed += changeset.bytes_changed;

However due to a completion bug, qgroup_free_reserved_data() will clear
EXTENT_QGROUP_RESERVED flag in BTRFS_I(inode)->io_failure_tree, other
than the correct BTRFS_I(inode)->io_tree.
Since io_failure_tree is never marked with that flag,
btrfs_qgroup_free_data() will not free any data reserved space at all,
causing a leakage.

This type of error handling can only be triggered by errors outside of
qgroup code. So EDQUOT error from qgroup can't trigger it.

[FIX]
Fix the wrong target io_tree.
Reported-by: NJosef Bacik <josef@toxicpanda.com>
Fixes: bc42bda2 ("btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: NNikolay Borisov <nborisov@suse.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

There may be situations when a server negotiates SMB 2.1
protocol version or higher but responds to a CREATE request
with an oplock rather than a lease.

Currently the client doesn't handle such a case correctly:
when another CREATE comes in the server sends an oplock
break to the initial CREATE and the client doesn't send
an ack back due to a wrong caching level being set (READ
instead of RWH). Missing an oplock break ack makes the
server wait until the break times out which dramatically
increases the latency of the second CREATE.

Fix this by properly detecting oplocks when using SMB 2.1
protocol version and higher.

Cc: <stable@vger.kernel.org>
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Various SMB3 ACL related flags (for security descriptor and
ACEs for example) were missing and some fields are different
in SMB3 and CIFS. Update cifsacl.h definitions based on
current MS-DTYP specification.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>

When brk was moved for binaries without an interpreter, it should have
been limited to ET_DYN only. In other words, the special case was an
ET_DYN that lacks an INTERP, not just an executable that lacks INTERP.
The bug manifested for giant static executables, where the brk would end
up in the middle of the text area on 32-bit architectures.
Reported-and-tested-by: NRichard Kojedzinszky <richard@kojedz.in>
Fixes: bbdc6076 ("binfmt_elf: move brk out of mmap when doing direct loader exec")
Cc: stable@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"likely(!IS_ERR(x))" is excessive. IS_ERR() already uses
unlikely() internally.

Link: http://lkml.kernel.org/r/20190829165025.15750-11-efremov@linux.comSigned-off-by: NDenis Efremov <efremov@linux.com>
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"unlikely(WARN_ON(x))" is excessive. WARN_ON() already uses unlikely()
internally.

Link: http://lkml.kernel.org/r/20190829165025.15750-7-efremov@linux.comSigned-off-by: NDenis Efremov <efremov@linux.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"unlikely(WARN_ON(x))" is excessive. WARN_ON() already uses unlikely()
internally.

Link: http://lkml.kernel.org/r/20190829165025.15750-5-efremov@linux.comSigned-off-by: NDenis Efremov <efremov@linux.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The mounting of jffs2 is broken due to the changes from the new mount API
because it specifies a "source" operation, but then doesn't actually
process it.  But because it specified it, it doesn't return -ENOPARAM and
the caller doesn't process it either and the source gets lost.

Fix this by simply removing the source parameter from jffs2 and letting the
VFS deal with it in the default manner.

To test it, enable CONFIG_MTD_MTDRAM and allow the default size and erase
block size parameters, then try and mount the /dev/mtdblock<N> file that
that creates as jffs2.  No need to initialise it.

Fixes: ec10a24f ("vfs: Convert jffs2 to use the new mount API")
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: Richard Weinberger <richard@nod.at>
cc: linux-mtd@lists.infradead.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For batched IO, it's not uncommon for waiters to ask for more than 1
IO to complete before being woken up. This is a problem with
wait_event() since tasks will get woken for every IO that completes,
re-check condition, then go back to sleep. For batch counts on the
order of what you do for high IOPS, that can result in 10s of extra
wakeups for the waiting task.

Add a private wake function that checks for the wake up count criteria
being met before calling autoremove_wake_function(). Pavel reports that
one test case he has runs 40% faster with proper batching of wakeups.
Reported-by: NPavel Begunkov <asml.silence@gmail.com>
Tested-by: NPavel Begunkov <asml.silence@gmail.com>
Reviewed-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We need to populate an ACL (security descriptor open context)
on file and directory correct.  This patch passes in the
mode.  Followon patch will build the open context and the
security descriptor (from the mode) that goes in the open
context.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>

This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.

userfaultfd code use provided user pointers for vma lookups, which can
only by done with untagged pointers.

Untag user pointers in validate_range().

Link: http://lkml.kernel.org/r/cdc59ddd7011012ca2e689bc88c3b65b1ea7e413.1563904656.git.andreyknvl@google.comSigned-off-by: NAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: NMike Rapoport <rppt@linux.ibm.com>
Reviewed-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.

In copy_mount_options a user address is being subtracted from TASK_SIZE.
If the address is lower than TASK_SIZE, the size is calculated to not
allow the exact_copy_from_user() call to cross TASK_SIZE boundary.
However if the address is tagged, then the size will be calculated
incorrectly.

Untag the address before subtracting.

Link: http://lkml.kernel.org/r/1de225e4a54204bfd7f25dac2635e31aa4aa1d90.1563904656.git.andreyknvl@google.comSigned-off-by: NAndrey Konovalov <andreyknvl@google.com>
Reviewed-by: NKhalid Aziz <khalid.aziz@oracle.com>
Reviewed-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

brelse() tests whether its argument is NULL and then returns immediately.
Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Link: http://lkml.kernel.org/r/cfff3b81-fb5d-af26-7b5e-724266509045@web.deSigned-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the following gcc warning:

fs/reiserfs/do_balan.c: In function balance_leaf_insert_right:
fs/reiserfs/do_balan.c:629:6: warning: variable ret set but not used
[-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/20190827032932.46622-2-yanaijie@huawei.comSigned-off-by: NJason Yan <yanaijie@huawei.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the following gcc warning:

fs/reiserfs/journal.c: In function flush_used_journal_lists:
fs/reiserfs/journal.c:1791:6: warning: variable ret set but not used
[-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/20190827032932.46622-1-yanaijie@huawei.comSigned-off-by: NJason Yan <yanaijie@huawei.com>
Cc: zhengbin <zhengbin13@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/reiserfs/do_balan.c: In function balance_leaf_when_delete:
fs/reiserfs/do_balan.c:245:20: warning: variable ih set but not used [-Wunused-but-set-variable]
fs/reiserfs/do_balan.c: In function balance_leaf_insert_left:
fs/reiserfs/do_balan.c:301:7: warning: variable version set but not used [-Wunused-but-set-variable]
fs/reiserfs/do_balan.c: In function balance_leaf_insert_right:
fs/reiserfs/do_balan.c:649:7: warning: variable version set but not used [-Wunused-but-set-variable]
fs/reiserfs/do_balan.c: In function balance_leaf_new_nodes_insert:
fs/reiserfs/do_balan.c:953:7: warning: variable version set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-8-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/reiserfs/fix_node.c: In function get_num_ver:
fs/reiserfs/fix_node.c:379:6: warning: variable cur_free set but not used [-Wunused-but-set-variable]
fs/reiserfs/fix_node.c: In function dc_check_balance_internal:
fs/reiserfs/fix_node.c:1737:6: warning: variable maxsize set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-7-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/reiserfs/prints.c: In function check_internal_block_head:
fs/reiserfs/prints.c:749:21: warning: variable blkh set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-6-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/reiserfs/objectid.c: In function reiserfs_convert_objectid_map_v1:
fs/reiserfs/objectid.c:186:25: warning: variable new_objectid_map set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-5-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/reiserfs/lbalance.c: In function leaf_paste_entries:
fs/reiserfs/lbalance.c:1325:9: warning: variable old_entry_num set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-4-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/reiserfs/stree.c: In function search_by_key:
fs/reiserfs/stree.c:596:6: warning: variable right_neighbor_of_leaf_node set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-3-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes gcc '-Wunused-but-set-variable' warning:

fs/reiserfs/journal.c: In function flush_older_commits:
fs/reiserfs/journal.c:894:15: warning: variable first_trans_id set but not used [-Wunused-but-set-variable]
fs/reiserfs/journal.c: In function flush_journal_list:
fs/reiserfs/journal.c:1354:38: warning: variable last set but not used [-Wunused-but-set-variable]
fs/reiserfs/journal.c: In function do_journal_release:
fs/reiserfs/journal.c:1916:6: warning: variable flushed set but not used [-Wunused-but-set-variable]
fs/reiserfs/journal.c: In function do_journal_end:
fs/reiserfs/journal.c:3993:6: warning: variable old_start set but not used [-Wunused-but-set-variable]

Link: http://lkml.kernel.org/r/1566379929-118398-2-git-send-email-zhengbin13@huawei.comSigned-off-by: Nzhengbin <zhengbin13@huawei.com>
Reported-by: NHulk Robot <hulkci@huawei.com>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On lines 3430-3434, bh has been assured to be non-null:
    cn = get_journal_hash_dev(sb, journal->j_hash_table, blocknr);
    if (!cn || !cn->bh) {
        return ret;
    }
    bh = cn->bh;

Thus, the check of bh on line 3447 is unnecessary and can be removed.
Thank Andrew Morton for good advice.

Link: http://lkml.kernel.org/r/20190727084019.11307-1-baijiaju1990@gmail.comSigned-off-by: NJia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Cc: Bharath Vedartham <linux.bhar@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The membarrier_state field is located within the mm_struct, which
is not guaranteed to exist when used from runqueue-lock-free iteration
on runqueues by the membarrier system call.

Copy the membarrier_state from the mm_struct into the scheduler runqueue
when the scheduler switches between mm.

When registering membarrier for mm, after setting the registration bit
in the mm membarrier state, issue a synchronize_rcu() to ensure the
scheduler observes the change. In order to take care of the case
where a runqueue keeps executing the target mm without swapping to
other mm, iterate over each runqueue and issue an IPI to copy the
membarrier_state from the mm_struct into each runqueue which have the
same mm which state has just been modified.

Move the mm membarrier_state field closer to pgd in mm_struct to use
a cache line already touched by the scheduler switch_mm.

The membarrier_execve() (now membarrier_exec_mmap) hook now needs to
clear the runqueue's membarrier state in addition to clear the mm
membarrier state, so move its implementation into the scheduler
membarrier code so it can access the runqueue structure.

Add memory barrier in membarrier_exec_mmap() prior to clearing
the membarrier state, ensuring memory accesses executed prior to exec
are not reordered with the stores clearing the membarrier state.

As suggested by Linus, move all membarrier.c RCU read-side locks outside
of the for each cpu loops.
Suggested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-5-mathieu.desnoyers@efficios.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

[BUG]
With v5.3 kernel, we can't convert to SINGLE profile:

  # btrfs balance start -f -dconvert=single $mnt
  ERROR: error during balancing '/mnt/btrfs': Invalid argument
  # dmesg -t | tail
  validate_convert_profile: data profile=0x1000000000000 allowed=0x20 is_valid=1 final=0x1000000000000 ret=1
  BTRFS error (device dm-3): balance: invalid convert data profile single

[CAUSE]
With the extra debug output added, it shows that the @allowed bit is
lacking the special in-memory only SINGLE profile bit.

Thus we fail at that (profile & ~allowed) check.

This regression is caused by commit 081db89b ("btrfs: use raid_attr
to get allowed profiles for balance conversion") and the fact that we
don't use any bit to indicate SINGLE profile on-disk, but uses special
in-memory only bit to help distinguish different profiles.

[FIX]
Add that BTRFS_AVAIL_ALLOC_BIT_SINGLE to @allowed, so the code should be
the same as it was and fix the regression.
Reported-by: NChris Murphy <lists@colorremedies.com>
Fixes: 081db89b ("btrfs: use raid_attr to get allowed profiles for balance conversion")
CC: stable@vger.kernel.org # 5.3+
Reviewed-by: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

[BUG]
One user reported a reproducible KASAN report about use-after-free:

  BTRFS info (device sdi1): balance: start -dvrange=1256811659264..1256811659265
  BTRFS info (device sdi1): relocating block group 1256811659264 flags data|raid0
  ==================================================================
  BUG: KASAN: use-after-free in btrfs_init_reloc_root+0x2cd/0x340 [btrfs]
  Write of size 8 at addr ffff88856f671710 by task kworker/u24:10/261579

  CPU: 2 PID: 261579 Comm: kworker/u24:10 Tainted: P           OE     5.2.11-arch1-1-kasan #4
  Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X99 Extreme4, BIOS P3.80 04/06/2018
  Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
  Call Trace:
   dump_stack+0x7b/0xba
   print_address_description+0x6c/0x22e
   ? btrfs_init_reloc_root+0x2cd/0x340 [btrfs]
   __kasan_report.cold+0x1b/0x3b
   ? btrfs_init_reloc_root+0x2cd/0x340 [btrfs]
   kasan_report+0x12/0x17
   __asan_report_store8_noabort+0x17/0x20
   btrfs_init_reloc_root+0x2cd/0x340 [btrfs]
   record_root_in_trans+0x2a0/0x370 [btrfs]
   btrfs_record_root_in_trans+0xf4/0x140 [btrfs]
   start_transaction+0x1ab/0xe90 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   btrfs_finish_ordered_io+0x7bf/0x18a0 [btrfs]
   ? lock_repin_lock+0x400/0x400
   ? __kmem_cache_shutdown.cold+0x140/0x1ad
   ? btrfs_unlink_subvol+0x9b0/0x9b0 [btrfs]
   finish_ordered_fn+0x15/0x20 [btrfs]
   normal_work_helper+0x1bd/0xca0 [btrfs]
   ? process_one_work+0x819/0x1720
   ? kasan_check_read+0x11/0x20
   btrfs_endio_write_helper+0x12/0x20 [btrfs]
   process_one_work+0x8c9/0x1720
   ? pwq_dec_nr_in_flight+0x2f0/0x2f0
   ? worker_thread+0x1d9/0x1030
   worker_thread+0x98/0x1030
   kthread+0x2bb/0x3b0
   ? process_one_work+0x1720/0x1720
   ? kthread_park+0x120/0x120
   ret_from_fork+0x35/0x40

  Allocated by task 369692:
   __kasan_kmalloc.part.0+0x44/0xc0
   __kasan_kmalloc.constprop.0+0xba/0xc0
   kasan_kmalloc+0x9/0x10
   kmem_cache_alloc_trace+0x138/0x260
   btrfs_read_tree_root+0x92/0x360 [btrfs]
   btrfs_read_fs_root+0x10/0xb0 [btrfs]
   create_reloc_root+0x47d/0xa10 [btrfs]
   btrfs_init_reloc_root+0x1e2/0x340 [btrfs]
   record_root_in_trans+0x2a0/0x370 [btrfs]
   btrfs_record_root_in_trans+0xf4/0x140 [btrfs]
   start_transaction+0x1ab/0xe90 [btrfs]
   btrfs_start_transaction+0x1e/0x20 [btrfs]
   __btrfs_prealloc_file_range+0x1c2/0xa00 [btrfs]
   btrfs_prealloc_file_range+0x13/0x20 [btrfs]
   prealloc_file_extent_cluster+0x29f/0x570 [btrfs]
   relocate_file_extent_cluster+0x193/0xc30 [btrfs]
   relocate_data_extent+0x1f8/0x490 [btrfs]
   relocate_block_group+0x600/0x1060 [btrfs]
   btrfs_relocate_block_group+0x3a0/0xa00 [btrfs]
   btrfs_relocate_chunk+0x9e/0x180 [btrfs]
   btrfs_balance+0x14e4/0x2fc0 [btrfs]
   btrfs_ioctl_balance+0x47f/0x640 [btrfs]
   btrfs_ioctl+0x119d/0x8380 [btrfs]
   do_vfs_ioctl+0x9f5/0x1060
   ksys_ioctl+0x67/0x90
   __x64_sys_ioctl+0x73/0xb0
   do_syscall_64+0xa5/0x370
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

  Freed by task 369692:
   __kasan_slab_free+0x14f/0x210
   kasan_slab_free+0xe/0x10
   kfree+0xd8/0x270
   btrfs_drop_snapshot+0x154c/0x1eb0 [btrfs]
   clean_dirty_subvols+0x227/0x340 [btrfs]
   relocate_block_group+0x972/0x1060 [btrfs]
   btrfs_relocate_block_group+0x3a0/0xa00 [btrfs]
   btrfs_relocate_chunk+0x9e/0x180 [btrfs]
   btrfs_balance+0x14e4/0x2fc0 [btrfs]
   btrfs_ioctl_balance+0x47f/0x640 [btrfs]
   btrfs_ioctl+0x119d/0x8380 [btrfs]
   do_vfs_ioctl+0x9f5/0x1060
   ksys_ioctl+0x67/0x90
   __x64_sys_ioctl+0x73/0xb0
   do_syscall_64+0xa5/0x370
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

  The buggy address belongs to the object at ffff88856f671100
   which belongs to the cache kmalloc-4k of size 4096
  The buggy address is located 1552 bytes inside of
   4096-byte region [ffff88856f671100, ffff88856f672100)
  The buggy address belongs to the page:
  page:ffffea0015bd9c00 refcount:1 mapcount:0 mapping:ffff88864400e600 index:0x0 compound_mapcount: 0
  flags: 0x2ffff0000010200(slab|head)
  raw: 02ffff0000010200 dead000000000100 dead000000000200 ffff88864400e600
  raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
  page dumped because: kasan: bad access detected

  Memory state around the buggy address:
   ffff88856f671600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   ffff88856f671680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  >ffff88856f671700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                           ^
   ffff88856f671780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   ffff88856f671800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ==================================================================
  BTRFS info (device sdi1): 1 enospc errors during balance
  BTRFS info (device sdi1): balance: ended with status: -28

[CAUSE]
The problem happens when finish_ordered_io() get called with balance
still running, while the reloc root of that subvolume is already dead.
(Tree is swap already done, but tree not yet deleted for possible qgroup
usage.)

That means root->reloc_root still exists, but that reloc_root can be
under btrfs_drop_snapshot(), thus we shouldn't access it.

The following race could cause the use-after-free problem:

                CPU1              |                CPU2
--------------------------------------------------------------------------
                                  | relocate_block_group()
                                  | |- unset_reloc_control(rc)
                                  | |- btrfs_commit_transaction()
btrfs_finish_ordered_io()         | |- clean_dirty_subvols()
|- btrfs_join_transaction()       |    |
   |- record_root_in_trans()      |    |
      |- btrfs_init_reloc_root()  |    |
         |- if (root->reloc_root) |    |
         |                        |    |- root->reloc_root = NULL
         |                        |    |- btrfs_drop_snapshot(reloc_root);
         |- reloc_root->last_trans|
                 = trans->transid |
	    ^^^^^^^^^^^^^^^^^^^^^^
            Use after free

[FIX]
Fix it by the following modifications:

- Test if the root has dead reloc tree before accessing root->reloc_root
  If the root has BTRFS_ROOT_DEAD_RELOC_TREE, then we don't need to
  create or update root->reloc_tree

- Clear the BTRFS_ROOT_DEAD_RELOC_TREE flag until we have fully dropped
  reloc tree
  To co-operate with above modification, so as long as
  BTRFS_ROOT_DEAD_RELOC_TREE is still set, we won't try to re-create
  reloc tree at record_root_in_trans().
Reported-by: NCebtenzzre <cebtenzzre@gmail.com>
Fixes: d2311e69 ("btrfs: relocation: Delay reloc tree deletion after merge_reloc_roots")
CC: stable@vger.kernel.org # 5.1+
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Reviewed-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NQu Wenruo <wqu@suse.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Additional reparse tags were described for WSL and file sync.
Add missing defines for these tags. Some will be useful for
POSIX extensions (as discussed at Storage Developer Conference).
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>

Patch series "Provide generic top-down mmap layout functions", v6.

This series introduces generic functions to make top-down mmap layout
easily accessible to architectures, in particular riscv which was the
initial goal of this series.  The generic implementation was taken from
arm64 and used successively by arm, mips and finally riscv.

Note that in addition the series fixes 2 issues:

- stack randomization was taken into account even if not necessary.

- [1] fixed an issue with mmap base which did not take into account
  randomization but did not report it to arm and mips, so by moving arm64
  into a generic library, this problem is now fixed for both
  architectures.

This work is an effort to factorize architecture functions to avoid code
duplication and oversights as in [1].

[1]: https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1429066.html

This patch (of 14):

This preparatory commit moves this function so that further introduction
of generic topdown mmap layout is contained only in mm/util.c.

Link: http://lkml.kernel.org/r/20190730055113.23635-2-alex@ghiti.frSigned-off-by: NAlexandre Ghiti <alex@ghiti.fr>
Acked-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NLuis Chamberlain <mcgrof@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In previous patch, an application could put part of its text section in
THP via madvise().  These THPs will be protected from writes when the
application is still running (TXTBSY).  However, after the application
exits, the file is available for writes.

This patch avoids writes to file THP by dropping page cache for the file
when the file is open for write.  A new counter nr_thps is added to struct
address_space.  In do_dentry_open(), if the file is open for write and
nr_thps is non-zero, we drop page cache for the whole file.

Link: http://lkml.kernel.org/r/20190801184244.3169074-8-songliubraving@fb.comSigned-off-by: NSong Liu <songliubraving@fb.com>
Reported-by: Nkbuild test robot <lkp@intel.com>
Acked-by: NRik van Riel <riel@surriel.com>
Acked-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>