linux-stable.git/fs, branch v4.12.7

btrfs: Remove false alert when fiemap range is smaller than on-disk extent

2017-08-13T02:34:28+00:00

commit 848c23b78fafdcd3270b06a30737f8dbd70c347f upstream.

Commit 4751832da990 ("btrfs: fiemap: Cache and merge fiemap extent before
submit it to user") introduced a warning to catch unemitted cached
fiemap extent.

However such warning doesn't take the following case into consideration:

0			4K			8K
|<---- fiemap range --->|
|<----------- On-disk extent ------------------>|

In this case, the whole 0~8K is cached, and since it's larger than
fiemap range, it break the fiemap extent emit loop.
This leaves the fiemap extent cached but not emitted, and caught by the
final fiemap extent sanity check, causing kernel warning.

This patch removes the kernel warning and renames the sanity check to
emit_last_fiemap_cache() since it's possible and valid to have cached
fiemap extent.

Reported-by: David Sterba 
Reported-by: Adam Borowski 
Fixes: 4751832da990 ("btrfs: fiemap: Cache and merge fiemap extent ...")
Signed-off-by: Qu Wenruo 
Signed-off-by: David Sterba 
Cc: Holger Hoffstätte 
Signed-off-by: Greg Kroah-Hartman

Btrfs: fix early ENOSPC due to delalloc

2017-08-11T15:33:54+00:00

commit 17024ad0a0fdfcfe53043afb969b813d3e020c21 upstream.

If a lot of metadata is reserved for outstanding delayed allocations, we
rely on shrink_delalloc() to reclaim metadata space in order to fulfill
reservation tickets. However, shrink_delalloc() has a shortcut where if
it determines that space can be overcommitted, it will stop early. This
made sense before the ticketed enospc system, but now it means that
shrink_delalloc() will often not reclaim enough space to fulfill any
tickets, leading to an early ENOSPC. (Reservation tickets don't care
about being able to overcommit, they need every byte accounted for.)

Fix it by getting rid of the shortcut so that shrink_delalloc() reclaims
all of the metadata it is supposed to. This fixes early ENOSPCs we were
seeing when doing a btrfs receive to populate a new filesystem, as well
as early ENOSPCs Christoph saw when doing a big cp -r onto Btrfs.

Fixes: 957780eb2788 ("Btrfs: introduce ticketed enospc infrastructure")
Tested-by: Christoph Anton Mitterer 
Reviewed-by: Josef Bacik 
Signed-off-by: Omar Sandoval 
Signed-off-by: David Sterba 
Signed-off-by: Nikolay Borisov 
Signed-off-by: Greg Kroah-Hartman

ext4: Don't clear SGID when inheriting ACLs

2017-08-11T15:33:54+00:00

commit a3bb2d5587521eea6dab2d05326abb0afb460abd upstream.

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0'). However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of
__ext4_set_acl() into ext4_set_acl(). That way the function will not be
called when inheriting ACLs which is what we want as it prevents SGID
bit clearing and the mode has been properly set by posix_acl_create()
anyway.

Fixes: 073931017b49d9458aa351605b43a7e34598caef
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jan Kara 
Reviewed-by: Andreas Gruenbacher 
Signed-off-by: Greg Kroah-Hartman

ext4: preserve i_mode if __ext4_set_acl() fails

2017-08-11T15:33:54+00:00

commit 397e434176bb62bc6068d2210af1d876c6212a7e upstream.

When changing a file's acl mask, __ext4_set_acl() will first set the group
bits of i_mode to the value of the mask, and only then set the actual
extended attribute representing the new acl.

If the second part fails (due to lack of space, for example) and the file
had no acl attribute to begin with, the system will from now on assume
that the mask permission bits are actual group permission bits, potentially
granting access to the wrong users.

Prevent this by only changing the inode mode after the acl has been set.

Signed-off-by: Ernesto A. Fernández 
Signed-off-by: Theodore Ts'o 
Reviewed-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ext4: fix overflow caused by missing cast in ext4_resize_fs()

2017-08-11T15:33:53+00:00

commit aec51758ce10a9c847a62a48a168f8c804c6e053 upstream.

On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd7173d66
Signed-off-by: Jerry Lee 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Greg Kroah-Hartman

ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize

2017-08-11T15:33:53+00:00

commit fcf5ea10992fbac3c7473a1db33d56a139333cd1 upstream.

ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:

  xfs_io -f -c "falloc 0 4k" \
            -c "pwrite 1k 1k" \
            -c "pwrite 3k 1k" \
            -c "seek -a -r 0" foo

In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.

Fix the problem by neglecting buffers in a page before starting offset.

Reported-by: Andreas Gruenbacher 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

ocfs2: don't clear SGID when inheriting ACLs

2017-08-11T15:33:51+00:00

commit 19ec8e48582670c021e998b9deb88e39a842ff45 upstream.

When new directory 'DIR1' is created in a directory 'DIR0' with SGID bit
set, DIR1 is expected to have SGID bit set (and owning group equal to
the owning group of 'DIR0').  However when 'DIR0' also has some default
ACLs that 'DIR1' inherits, setting these ACLs will result in SGID bit on
'DIR1' to get cleared if user is not member of the owning group.

Fix the problem by moving posix_acl_update_mode() out of ocfs2_set_acl()
into ocfs2_iop_set_acl().  That way the function will not be called when
inheriting ACLs which is what we want as it prevents SGID bit clearing
and the mode has been properly set by posix_acl_create() anyway.  Also
posix_acl_chmod() that is calling ocfs2_set_acl() takes care of updating
mode itself.

Fixes: 073931017b4 ("posix_acl: Clear SGID bit when setting file permissions")
Link: http://lkml.kernel.org/r/20170801141252.19675-3-jack@suse.cz
Signed-off-by: Jan Kara 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Cc: Joseph Qi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

userfaultfd: non-cooperative: flush event_wqh at release time

2017-08-11T15:33:51+00:00

commit 5a18b64e3f02125be1c0ef777501ae38aafe2a24 upstream.

There may still be threads waiting on event_wqh at the time the
userfault file descriptor is closed.  Flush the events wait-queue to
prevent waiting threads from hanging.

Link: http://lkml.kernel.org/r/1501398127-30419-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 9cd75c3cd4c3d ("userfaultfd: non-cooperative: add ability to report
non-PF events from uffd descriptor")
Signed-off-by: Mike Rapoport 
Cc: Andrea Arcangeli 
Cc: "Dr. David Alan Gilbert" 
Cc: Pavel Emelyanov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

userfaultfd_zeropage: return -ENOSPC in case mm has gone

2017-08-11T15:33:51+00:00

commit 9d95aa4bada24be35bb94827a55e1d6e243d866e upstream.

In the non-cooperative userfaultfd case, the process exit may race with
outstanding mcopy_atomic called by the uffd monitor.  Returning -ENOSPC
instead of -EINVAL when mm is already gone will allow uffd monitor to
distinguish this case from other error conditions.

Unfortunately I overlooked userfaultfd_zeropage when updating
userfaultd_copy().

Link: http://lkml.kernel.org/r/1501136819-21857-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 96333187ab162 ("userfaultfd_copy: return -ENOSPC in case mm has gone")
Signed-off-by: Mike Rapoport 
Cc: Andrea Arcangeli 
Cc: "Dr. David Alan Gilbert" 
Cc: Pavel Emelyanov 
Cc: Michal Hocko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

NFSv4: Fix EXCHANGE_ID corrupt verifier issue

2017-08-11T15:33:50+00:00

commit fd40559c8657418385e42f797e0b04bfc0add748 upstream.

The verifier is allocated on the stack, but the EXCHANGE_ID RPC call was
changed to be asynchronous by commit 8d89bd70bc939. If we interrrupt
the call to rpc_wait_for_completion_task(), we can therefore end up
transmitting random stack contents in lieu of the verifier.

Fixes: 8d89bd70bc939 ("NFS setup async exchange_id")
Signed-off-by: Trond Myklebust 
Signed-off-by: Anna Schumaker 
Signed-off-by: Greg Kroah-Hartman