Commit Graph

44980 Commits

Author SHA1 Message Date
Miklos Szeredi a999d7e161 ovl: permission: return ECHILD instead of ENOENT
The error is due to RCU and is temporary.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Miklos Szeredi d719e8f268 ovl: update atime on upper
Fix atime update logic in overlayfs.

This patch adds an i_op->update_time() handler to overlayfs inodes.  This
forwards atime updates to the upper layer only.  No atime updates are done
on lower layers.

Remove implicit atime updates to underlying files and directories with
O_NOATIME.  Remove explicit atime update in ovl_readlink().

Clear atime related mnt flags from cloned upper mount.  This means atime
updates are controlled purely by overlayfs mount options.

Reported-by: Konstantin Khlebnikov <koct9i@gmail.com> 
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Miklos Szeredi bb0d2b8ad2 ovl: fix sgid on directory
When creating directory in workdir, the group/sgid inheritance from the
parent dir was omitted completely.  Fix this by calling inode_init_owner()
on overlay inode and using the resulting uid/gid/mode to create the file.

Unfortunately the sgid bit can be stripped off due to umask, so need to
reset the mode in this case in workdir before moving the directory in
place.

Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Miklos Szeredi 9c630ebefe ovl: simplify permission checking
The fact that we always do permission checking on the overlay inode and
clear MAY_WRITE for checking access to the lower inode allows cruft to be
removed from ovl_permission().

1) "default_permissions" option effectively did generic_permission() on the
overlay inode with i_mode, i_uid and i_gid updated from underlying
filesystem.  This is what we do by default now.  It did the update using
vfs_getattr() but that's only needed if the underlying filesystem can
change (which is not allowed).  We may later introduce a "paranoia_mode"
that verifies that mode/uid/gid are not changed.

2) splitting out the IS_RDONLY() check from inode_permission() also becomes
unnecessary once we remove the MAY_WRITE from the lower inode check.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal 754f8cb72b ovl: do not require mounter to have MAY_WRITE on lower
Now we have two levels of checks in ovl_permission(). overlay inode
is checked with the creds of task while underlying inode is checked
with the creds of mounter.

Looks like mounter does not have to have WRITE access to files on lower/.
So remove the MAY_WRITE from access mask for checks on underlying
lower inode.

This means task should still have the MAY_WRITE permission on lower
inode and mounter is not required to have MAY_WRITE.

It also solves the problem of read only NFS mounts being used as lower.
If __inode_permission(lower_inode, MAY_WRITE) is called on read only
NFS, it fails. By resetting MAY_WRITE, check succeeds and case of
read only NFS shold work with overlay without having to specify any
special mount options (default permission).

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal 1175b6b8d9 ovl: do operations on underlying file system in mounter's context
Given we are now doing checks both on overlay inode as well underlying
inode, we should be able to do checks and operations on underlying file
system using mounter's context.

So modify all operations to do checks/operations on underlying dentry/inode
in the context of mounter.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal c0ca3d70e8 ovl: modify ovl_permission() to do checks on two inodes
Right now ovl_permission() calls __inode_permission(realinode), to do
permission checks on real inode and no checks are done on overlay inode.

Modify it to do checks both on overlay inode as well as underlying inode.
Checks on overlay inode will be done with the creds of calling task while
checks on underlying inode will be done with the creds of mounter.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal 39a25b2b37 ovl: define ->get_acl() for overlay inodes
Now we are planning to do DAC permission checks on overlay inode
itself. And to make it work, we will need to make sure we can get acls from
underlying inode. So define ->get_acl() for overlay inodes and this in turn
calls into underlying filesystem to get acls, if any.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Vivek Goyal 72e4848181 ovl: move some common code in a function
ovl_create_upper() and ovl_create_over_whiteout() seem to be sharing some
common code which can be moved into a separate function.  No functionality
change.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:23 +02:00
Andreas Gruenbacher 58ed4e70f2 ovl: store ovl_entry in inode->i_private for all inodes
Previously this was only done for directory inodes.  Doing so for all
inodes makes for a nice cleanup in ovl_permission at zero cost.

Inodes are not shared for hard links on the overlay, so this works fine.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:22 +02:00
Miklos Szeredi eead4f2dc4 ovl: use generic_delete_inode
No point in keeping overlay inodes around since they will never be reused.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29 12:05:22 +02:00
Miklos Szeredi c1b2cc1a76 ovl: check mounter creds on underlying lookup
The hash salting changes meant that we can no longer reuse the hash in the
overlay dentry to look up the underlying dentry.

Instead of lookup_hash(), use lookup_one_len_unlocked() and swith to
mounter's creds (like we do for all other operations later in the series).

Now the lookup_hash() export introduced in 4.6 by 3c9fe8cdff ("vfs: add
lookup_hash() helper") is unused and can possibly be removed; its
usefulness negated by the hash salting and the idea that mounter's creds
should be used on operations on underlying filesystems.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 8387ff2577 ("vfs: make the string hashes salt the hash")
2016-07-29 12:05:22 +02:00
Miklos Szeredi 1b91dbdd29 Merge branch 'd_real' into overlayfs-next 2016-07-27 11:36:03 +02:00
Linus Torvalds 88083e9845 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "This contains a fix for a potential crash/corruption issue and another
  where the suid/sgid bits weren't cleared on write"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: verify upper dentry in ovl_remove_and_whiteout()
  ovl: Copy up underlying inode's ->i_mode to overlay inode
  ovl: handle ATTR_KILL*
2016-07-23 14:25:02 +09:00
Maxim Patlasov cfc9fde0b0 ovl: verify upper dentry in ovl_remove_and_whiteout()
The upper dentry may become stale before we call ovl_lock_rename_workdir.
For example, someone could (mistakenly or maliciously) manually unlink(2)
it directly from upperdir.

To ensure it is not stale, let's lookup it after ovl_lock_rename_workdir
and and check if it matches the upper dentry.

Essentially, it is the same problem and similar solution as in
commit 11f3710417 ("ovl: verify upper dentry before unlink and rename").

Signed-off-by: Maxim Patlasov <mpatlasov@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-07-22 10:54:20 +02:00
Jann Horn 3e0a396546 xfs: fix type confusion in xfs_ioc_swapext
Without this check, the following XFS_I invocations would return bad
pointers when used on non-XFS inodes (perhaps pointers into preceding
allocator chunks).

This could be used by an attacker to trick xfs_swap_extents into
performing locking operations on attacker-chosen structures in kernel
memory, potentially leading to code execution in the kernel.  (I have
not investigated how likely this is to be usable for an attack in
practice.)

Signed-off-by: Jann Horn <jann@thejh.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-16 06:30:06 +09:00
Linus Torvalds 08d27eb206 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  posix_acl: de-union a_refcount and a_rcu
  nfs_atomic_open(): prevent parallel nfs_lookup() on a negative hashed
  Use the right predicate in ->atomic_open() instances
2016-07-12 16:49:01 +09:00
Linus Torvalds b987c759d2 eCryptfs fixes for 4.7-rc7:
- Provide a more concise fix for CVE-2016-1583
   + Additionally fixes linux-stable regressions caused by the cherry-picking of
     the original fix
 - Some very minor changes that have queued up
   + Fix typos in code comments
   + Remove unnecessary check for NULL before destroying kmem_cache
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABCgAGBQJXf8nnAAoJENaSAD2qAscKwXgP/0awhY1z40dL/igP6fPv2ack
 HbqrOjUVO2DzxinvKB3vRLNy93zwESxe8UpwPsl84IJ85zOQjkUkJ8PYk1oyBf0N
 dVWqO11g6AKNZ+VQFspconvMhZATwSrsv8z3BzvwNGLsPhPuUQ+JmbBe8xMdrsZ5
 qVaWswsMtMlhM3p/zFh57vWO64fT1xiabpxSkKpG2LHJN6h6QAQxkfBfa2FuXCsN
 hZIw+ULcUJfdawXGq8lAfcYzbDmFpNt70fFquJgfJHrXFrOuensYfLcWUvhrSNbc
 HZ6imRK9LCG4IKjJTBNmCmBR8ho71yGzdKuup81Eap+2zx2kC7twokS1d5fha8iL
 Kzkx0NMDriY2N+tIfufHYk2IIenFzWG6Yuj0STswtJX4YhQGBc0H6VxcgrxE0PgW
 k1iKUV7jnJGxxN+d6lmV4+fX0vKGgBMsQq1Q76CkYLN1BAvdwz6GnWSfqP8hWz3o
 sNVyNtYh+/TXY8JMWKDBlps7Ib8W88qDW3K7YcAf2VPYAqIWm5Va1MR5m5s+UIeR
 QiCD32X/0PfDp13QRiKAHJ6C9CInyu0r+fF/g8ZMqLuWgLxoahxpr6ML/CnHoGl5
 IcDydJO3/bLBq9If8WxYsOQvVKCa4e7N7o7ZHPKd8U7O39mCGNfbQx7/FlMjtvf6
 +4HAxamUC1ogpLTkpWxI
 =Bt4P
 -----END PGP SIGNATURE-----

Merge tag 'ecryptfs-4.7-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull eCryptfs fixes from Tyler Hicks:
 "Provide a more concise fix for CVE-2016-1583:
   - Additionally fixes linux-stable regressions caused by the
     cherry-picking of the original fix

  Some very minor changes that have queued up:
   - Fix typos in code comments
   - Remove unnecessary check for NULL before destroying kmem_cache"

* tag 'ecryptfs-4.7-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  ecryptfs: don't allow mmap when the lower fs doesn't support it
  Revert "ecryptfs: forbid opening files without mmap handler"
  ecryptfs: fix spelling mistakes
  eCryptfs: fix typos in comment
  ecryptfs: drop null test before destroy functions
2016-07-08 09:48:28 -07:00
Jeff Mahoney f0fe970df3 ecryptfs: don't allow mmap when the lower fs doesn't support it
There are legitimate reasons to disallow mmap on certain files, notably
in sysfs or procfs.  We shouldn't emulate mmap support on file systems
that don't offer support natively.

CVE-2016-1583

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: stable@vger.kernel.org
[tyhicks: clean up f_op check by using ecryptfs_file_to_lower()]
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2016-07-08 10:35:28 -05:00
Jeff Mahoney 78c4e17241 Revert "ecryptfs: forbid opening files without mmap handler"
This reverts commit 2f36db7100.

It fixed a local root exploit but also introduced a dependency on
the lower file system implementing an mmap operation just to open a file,
which is a bit of a heavy hammer.  The right fix is to have mmap depend
on the existence of the mmap handler instead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
2016-07-07 18:47:57 -05:00
Linus Torvalds ac904ae6e6 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block IO fixes from Jens Axboe:
 "Three small fixes that have been queued up and tested for this series:

   - A bug fix for xen-blkfront from Bob Liu, fixing an issue with
     incomplete requests during migration.

   - A fix for an ancient issue in retrieving the IO priority of a
     different PID than self, preventing that task from going away while
     we access it.  From Omar.

   - A writeback fix from Tahsin, fixing a case where we'd call ihold()
     with a zero ref count inode"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix use-after-free in sys_ioprio_get()
  writeback: inode cgroup wb switch should not call ihold()
  xen-blkfront: save uncompleted reqs in blkfront_resume()
2016-07-07 15:34:09 -07:00
Linus Torvalds 4c2a8499a4 Configfs fixes for Linux 4.7:
- a fix from Marek for ppos handling in configfs_write_bin_file,
    which was introduced in Linux 4.5, but didn't have any users
    until recently.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJXfjK1AAoJEA+eU2VSBFGDJ0kQAMZHONK7pHwM+IxDUeTsDTfa
 FX+EplF1rLEtmUGOl01XbjgQp7acsP19YWikQfC09+ZjF6Vn1zFAFlNoU3qM+i/2
 zdukzIRBaSM+4w4HFDQ548zGGc8e9mesIIUHrHt6n/nL0OLKTU0XzbmRMXmvXAUJ
 u0nuB0OYlFJEVQFIlDYfG6E2rJy37FPilToonfw+AryVDenRm9iiUt0iMFoA8wPG
 EpogUinelxrKZ+ysOEeibaTGxxLLbd3AbWeUQbkhmsk4FfxuV7GFSfGPbhmJ1LeU
 n5X3LbK8lixG8goGdAW1NYulLnTjprZ6emUL0jwxYmI+MzOP7DUcsLqsGmdh5LEa
 Uw5gzQnzNDOUFR8XFt5CgARUHRXeDyJfzKeWvKFd4JUink6wE9R0yQJ2bPBXu3pY
 7t0P4qQSKWdeGjmYg54/JBamMba7BLQOLZuuiAplTTAt5Dg4tEi9Zuje2sUmBcDn
 3YnG4dnGxPeP9EKCElh1WWtwiRItUKT+YtaqSinL1Rh2j1aWu9WJQ3M1C+s3hFQ3
 vGR/CchllLtP4xmpY9TXEpUbBp4ZnTercWAxLRczi1/kOm3SdMIMUak26U6pTBmN
 QfkEzSx+K5F1wGaoqa2j7MuTMSNsxfT1R0xA6aBid4oOyCoPyHOVJ3mqV0AziyOl
 c7B92HgR/aGFMEevVA1G
 =mZ2H
 -----END PGP SIGNATURE-----

Merge tag 'configfs-for-4.7' of git://git.infradead.org/users/hch/configfs

Pull configfs fix from Christoph Hellwig:
 "A fix from Marek for ppos handling in configfs_write_bin_file, which
  was introduced in Linux 4.5, but didn't have any users until recently"

* tag 'configfs-for-4.7' of git://git.infradead.org/users/hch/configfs:
  configfs: Remove ppos increment in configfs_write_bin_file
2016-07-07 15:32:17 -07:00
Al Viro c94c09535c nfs_atomic_open(): prevent parallel nfs_lookup() on a negative hashed
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:31 -04:00
Al Viro 00699ad857 Use the right predicate in ->atomic_open() instances
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache.  Use d_in_lookup() to tell one from another, rather
than d_unhashed().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:23 -04:00
Vivek Goyal 07a2daab49 ovl: Copy up underlying inode's ->i_mode to overlay inode
Right now when a new overlay inode is created, we initialize overlay
inode's ->i_mode from underlying inode ->i_mode but we retain only
file type bits (S_IFMT) and discard permission bits.

This patch changes it and retains permission bits too. This should allow
overlay to do permission checks on overlay inode itself in task context.

[SzM] It also fixes clearing suid/sgid bits on write.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
2016-07-04 16:49:48 +02:00
Miklos Szeredi b99c2d9138 ovl: handle ATTR_KILL*
Before 4bacc9c923 ("overlayfs: Make f_path...") file->f_path pointed to
the underlying file, hence suid/sgid removal on write worked fine.

After that patch file->f_path pointed to the overlay file, and the file
mode bits weren't copied to overlay_inode->i_mode.  So the suid/sgid
removal simply stopped working.

The fix is to copy the mode bits, but then ovl_setattr() needs to clear
ATTR_MODE to avoid the BUG() in notify_change().  So do this first, then in
the next patch copy the mode.

Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
2016-07-04 16:49:48 +02:00
Linus Torvalds 0b295dd5b8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fix from Miklos Szeredi:
 "This makes sure userspace filesystems are not broken by the parallel
  lookups and readdir feature"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: serialize dirops by default
2016-07-03 12:02:00 -07:00
Linus Torvalds 236bfd8ed8 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "This contains fixes for a dentry leak, a regression in 4.6 noticed by
  Docker users and missing write access checking in truncate"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: warn instead of error if d_type is not supported
  ovl: get_write_access() in truncate
  ovl: fix dentry leak for default_permissions
2016-07-03 11:57:09 -07:00
Vivek Goyal e7c0b5991d ovl: warn instead of error if d_type is not supported
overlay needs underlying fs to support d_type. Recently I put in a
patch in to detect this condition and started failing mount if
underlying fs did not support d_type.

But this breaks existing configurations over kernel upgrade. Those who
are running docker (partially broken configuration) with xfs not
supporting d_type, are surprised that after kernel upgrade docker does
not run anymore.

https://github.com/docker/docker/issues/22937#issuecomment-229881315

So instead of erroring out, detect broken configuration and warn
about it. This should allow existing docker setups to continue
working after kernel upgrade.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 45aebeaf4f ("ovl: Ensure upper filesystem supports d_type")
Cc: <stable@vger.kernel.org> 4.6
2016-07-03 09:39:31 +02:00
Linus Torvalds 48c4565ed6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Tmpfs readdir throughput regression fix (this cycle) + some -stable
  fodder all over the place.

  One missing bit is Miklos' tonight locks.c fix - NFS folks had already
  grabbed that one by the time I woke up ;-)"

[ The locks.c fix came through the nfsd tree just moments ago ]

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  namespace: update event counter when umounting a deleted dentry
  9p: use file_dentry()
  ceph: fix d_obtain_alias() misuses
  lockless next_positive()
  libfs.c: new helper - next_positive()
  dcache_{readdir,dir_lseek}(): don't bother with nested ->d_lock
2016-07-01 15:20:11 -07:00
Linus Torvalds 2728c57fda One fix for lockd soft lookups in an error path, and one fix for file
leases on overlayfs.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJXdr1UAAoJECebzXlCjuG+QlsQAJiZTmio6k9tupN5+iKsZNL3
 m919ooj8GYsXxlC0OTFfi09dUi1yeF8MEE3j9egk/+qxEtsdmKdEOIy0RVdcLSfd
 HeGjXgLh79hVcGxgyBP+pdax2XhZ3RVisg8F5gTw2GPo+FPFZfrEuO5h7ctn+t45
 MCQ+4yqYqzEhYnoPyo5XKh5Aj6wBWiaTzg3/jSe6uSuSfuBfyaMaBPq7l7ayGra/
 5El+tu61o/SrJ41N2EayWSj/bOFJE92LIuGOh8NdfANuuP70JhxlwgVSldah3CCQ
 6PymXAVcjw0+gJ00mokzKfTJW5FPfasxckMHaOvcFsSONy4rlmrwwqUr9C2AFzTE
 wQGIzibCDYOSI8uF+//Oe+dh8JWp2TF8rfJcmKLyJMIcCq/Xl6cNx1qrq/oSWvuk
 WKOv1otJrPeT31h/s5iLjr/E/Po1eX+d2ySJdvUHYu/5aZwFgWPnVXwJk0s9bLow
 auZU85tPnuz+tbS2pWEK+el7LMgDBdzraVRogMdH1c+m3+G9pr53EzmpYovkZ2X8
 duVJ2Leslyya347TnJAgEY47Fbeu26JaoeIChGVhKcEyCENlcqAJWaGVECrxvs3y
 p/Y2MYMkO8YrCz5wQXPiLFiG4rAc+jSIn1Q+vRGl2Pkel0y7AgJNNMFtANjMCSIO
 pg6BqUjOyKt8cXVy4UW7
 =K0mr
 -----END PGP SIGNATURE-----

Merge tag 'nfsd-4.7-3' of git://linux-nfs.org/~bfields/linux

Pull lockd/locks fixes from Bruce Fields:
 "One fix for lockd soft lookups in an error path, and one fix for file
  leases on overlayfs"

* tag 'nfsd-4.7-3' of git://linux-nfs.org/~bfields/linux:
  locks: use file_inode()
  lockd: unregister notifier blocks if the service fails to come up completely
2016-07-01 15:18:49 -07:00
Linus Torvalds f3683ccd12 Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "1/ Two regression fixes since v4.6: one for the byte order of a sysfs
     attribute (bz121161) and another for QEMU 2.6's NVDIMM _DSM (ACPI
     Device Specific Method) implementation that gets tripped up by new
     auto-probing behavior in the NFIT driver.

  2/ A fix tagged for -stable that stops the kernel from
     clobbering/ignoring changes to the configuration of a 'pfn'
     instance ("struct page" driver).  For example changing the
     alignment from 2M to 1G may silently revert to 2M if that value is
     currently stored on media.

  3/ A fix from Eric for an xfstests failure in dax.  It is not
     currently tagged for -stable since it requires an 8-exabyte file
     system to trigger, and there appear to be no user visible side
     effects"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  nfit: fix format interface code byte order
  dax: fix offset overflow in dax_io
  acpi, nfit: fix acpi_check_dsm() vs zero functions implemented
  libnvdimm, pfn, dax: fix initialization vs autodetect for mode + alignment
2016-07-01 15:15:03 -07:00
Miklos Szeredi 6343a21208 locks: use file_inode()
(Another one for the f_path debacle.)

ltp fcntl33 testcase caused an Oops in selinux_file_send_sigiotask.

The reason is that generic_add_lease() used filp->f_path.dentry->inode
while all the others use file_inode().  This makes a difference for files
opened on overlayfs since the former will point to the overlay inode the
latter to the underlying inode.

So generic_add_lease() added the lease to the overlay inode and
generic_delete_lease() removed it from the underlying inode.  When the file
was released the lease remained on the overlay inode's lock list, resulting
in use after free.

Reported-by: Eryu Guan <eguan@redhat.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-01 10:24:18 -04:00
Andrey Ulanov e06b933e6d namespace: update event counter when umounting a deleted dentry
- m_start() in fs/namespace.c expects that ns->event is incremented each
  time a mount added or removed from ns->list.
- umount_tree() removes items from the list but does not increment event
  counter, expecting that it's done before the function is called.
- There are some codepaths that call umount_tree() without updating
  "event" counter. e.g. from __detach_mounts().
- When this happens m_start may reuse a cached mount structure that no
  longer belongs to ns->list (i.e. use after free which usually leads
  to infinite loop).

This change fixes the above problem by incrementing global event counter
before invoking umount_tree().

Change-Id: I622c8e84dcb9fb63542372c5dbf0178ee86bb589
Cc: stable@vger.kernel.org
Signed-off-by: Andrey Ulanov <andreyu@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-30 23:28:30 -04:00
Miklos Szeredi b403f0e37a 9p: use file_dentry()
v9fs may be used as lower layer of overlayfs and accessing f_path.dentry
can lead to a crash.  In this case it's a NULL pointer dereference in
p9_fid_create().

Fix by replacing direct access of file->f_path.dentry with the
file_dentry() accessor, which will always return a native object.

Reported-by: Alessio Igor Bogani <alessioigorbogani@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Tested-by: Alessio Igor Bogani <alessioigorbogani@gmail.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-30 23:28:09 -04:00
Scott Mayhew cb7d224f82 lockd: unregister notifier blocks if the service fails to come up completely
If the lockd service fails to start up then we need to be sure that the
notifier blocks are not registered, otherwise a subsequent start of the
service could cause the same notifier to be registered twice, leading to
soft lockups.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 0751ddf77b "lockd: Register callbacks on the inetaddr_chain..."
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-06-30 16:35:07 -04:00
Tahsin Erdogan 7452495555 writeback: inode cgroup wb switch should not call ihold()
Asynchronous wb switching of inodes takes an additional ref count on an
inode to make sure inode remains valid until switchover is completed.

However, anyone calling ihold() must already have a ref count on inode,
but in this case inode->i_count may already be zero:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 917 at fs/inode.c:397 ihold+0x2b/0x30
CPU: 1 PID: 917 Comm: kworker/u4:5 Not tainted 4.7.0-rc2+ #49
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs
01/01/2011
Workqueue: writeback wb_workfn (flush-8:16)
 0000000000000000 ffff88007ca0fb58 ffffffff805990af 0000000000000000
 0000000000000000 ffff88007ca0fb98 ffffffff80268702 0000018d000004e2
 ffff88007cef40e8 ffff88007c9b89a8 ffff880079e3a740 0000000000000003
Call Trace:
 [<ffffffff805990af>] dump_stack+0x4d/0x6e
 [<ffffffff80268702>] __warn+0xc2/0xe0
 [<ffffffff802687d8>] warn_slowpath_null+0x18/0x20
 [<ffffffff8035b4ab>] ihold+0x2b/0x30
 [<ffffffff80367ecc>] inode_switch_wbs+0x11c/0x180
 [<ffffffff80369110>] wbc_detach_inode+0x170/0x1a0
 [<ffffffff80369abc>] writeback_sb_inodes+0x21c/0x530
 [<ffffffff80369f7e>] wb_writeback+0xee/0x1e0
 [<ffffffff8036a147>] wb_workfn+0xd7/0x280
 [<ffffffff80287531>] ? try_to_wake_up+0x1b1/0x2b0
 [<ffffffff8027bb09>] process_one_work+0x129/0x300
 [<ffffffff8027be06>] worker_thread+0x126/0x480
 [<ffffffff8098cde7>] ? __schedule+0x1c7/0x561
 [<ffffffff8027bce0>] ? process_one_work+0x300/0x300
 [<ffffffff80280ff4>] kthread+0xc4/0xe0
 [<ffffffff80335578>] ? kfree+0xc8/0x100
 [<ffffffff809903cf>] ret_from_fork+0x1f/0x40
 [<ffffffff80280f30>] ? __kthread_parkme+0x70/0x70
---[ end trace aaefd2fd9f306bc4 ]---

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-30 13:58:41 -06:00
Miklos Szeredi 5c672ab3f0 fuse: serialize dirops by default
Negotiate with userspace filesystems whether they support parallel readdir
and lookup.  Disable parallelism by default for fear of breaking fuse
filesystems.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 9902af79c0 ("parallel lookups: actual switch to rwsem")
Fixes: d9b3dbdcfd ("fuse: switch to ->iterate_shared()")
2016-06-30 13:10:49 +02:00
Marek Vasut f8608985f8 configfs: Remove ppos increment in configfs_write_bin_file
The simple_write_to_buffer() already increments the @ppos on success,
see fs/libfs.c simple_write_to_buffer() comment:

"
On success, the number of bytes written is returned and the offset @ppos
advanced by this number, or negative value is returned on error.
"

If the configfs_write_bin_file() is invoked with @count smaller than the
total length of the written binary file, it will be invoked multiple times.
Since configfs_write_bin_file() increments @ppos on success, after calling
simple_write_to_buffer(), the @ppos is incremented twice.

Subsequent invocation of configfs_write_bin_file() will result in the next
piece of data being written to the offset twice as long as the length of
the previous write, thus creating buffer with "holes" in it.

The simple testcase using DTO follows:
  $ mkdir /sys/kernel/config/device-tree/overlays/1
  $ dd bs=1 if=foo.dtbo of=/sys/kernel/config/device-tree/overlays/1/dtbo
Without this patch, the testcase will result in twice as big buffer in the
kernel, which is then passed to the cfs_overlay_item_dtbo_write() .

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
2016-06-30 11:28:55 +02:00
Miklos Szeredi 2d902671ce vfs: merge .d_select_inode() into .d_real()
The two methods essentially do the same: find the real dentry/inode
belonging to an overlay dentry.  The difference is in the usage:

vfs_open() uses ->d_select_inode() and expects the function to perform
copy-up if necessary based on the open flags argument.

file_dentry() uses ->d_real() passing in the overlay dentry as well as the
underlying inode.

vfs_rename() uses ->d_select_inode() but passes zero flags.  ->d_real()
with a zero inode would have worked just as well here.

This patch merges the functionality of ->d_select_inode() into ->d_real()
by adding an 'open_flags' argument to the latter.

[Al Viro] Make the signature of d_real() match that of ->d_real() again.
And constify the inode argument, while we are at it.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-06-30 08:53:27 +02:00
Linus Torvalds e7bdea7750 NFS client bugfixes for Linux 4.7
Stable bugfixes:
 - Fix _cancel_empty_pagelist
 - Fix a double page unlock
 - Make nfs_atomic_open() call d_drop() on all ->open_context() errors.
 - Fix another OPEN_DOWNGRADE bug
 
 Other bugfixes:
 - Ensure we handle delegation errors in nfs4_proc_layoutget()
 - Layout stateids start out as being invalid
 - Add sparse lock annotations for pnfs_find_alloc_layout
 - Handle bad delegation stateids in nfs4_layoutget_handle_exception
 - Fix up O_DIRECT results
 - Fix potential use after free of state in nfs4_do_reclaim.
 - Mark the layout stateid invalid when all segments are removed
 - Don't let readdirplus revalidate an inode that was marked as stale
 - Fix potential race in nfs_fhget()
 - Fix an unused variable warning
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJXdDWkAAoJENfLVL+wpUDrpsUP/1F2zu12r/Zkv3ZEFhShcpQc
 2N1TRD9X7Lruod2pUD95qqjjdw+/vu3LjcyJljrasRaJENijvZ2GQhKkB7xPODlu
 qxZcmnQsH+WmpmJKcqAByAW1czcNGMoMHnt4tV0gG21NH+XUb92fgn+aGeIJDVrK
 Hcd9d8TfnFWO70ZgTUXW/hv0CXwu4MEJhN2JfF4lolbxUkmjLHHLoxSDDm0AdXGC
 EE8f0V9/7xurvOeLe5bQOQXfZPedBydsLNXa1ZacMGKgmBUoRNxJ5yCpPUtcTVBx
 HwbiY+WDFQ7MdKTzUQqqbnrIqKw8Hu4SugIV/vHRqR+Lhc6u29YGOqdU4d2G8IKW
 Nh8MBqS+dDefCkL3TJoE7MpjhP3EOO6HXnv5FjMZLOuu2X2o+Sz3+DkhYCq6pj/g
 fFh480vZfZYaTsfDf1ttvVN8kIvQ+1Uk3LK6aC2EVwgPrv+0OIRu36F0JQQimxOp
 EbYDlhVk7mzH/ZQ31GmPPbSIk+3sm2V58lqXnUMovoqPFPiN3xZDuBcnlyFrrzaI
 NjOvsdVxkOdHWbYZyBQzj16Vo651EYbAAUEwsud70N8C3aCgkTxCZ30Q0v+KqqxU
 pP5kz3zYUdkXQeHxE6T0iXG9fGcv/nGS21hTfT01YJCK7v67K8TYRNMrOEVURVgk
 LSD/CZJXJHVJn1Vr4F7o
 =IGNO
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.7-2' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client bugfixes from Anna Schumaker:
 "Stable bugfixes:
   - Fix _cancel_empty_pagelist
   - Fix a double page unlock
   - Make nfs_atomic_open() call d_drop() on all ->open_context() errors.
   - Fix another OPEN_DOWNGRADE bug

  Other bugfixes:
   - Ensure we handle delegation errors in nfs4_proc_layoutget()
   - Layout stateids start out as being invalid
   - Add sparse lock annotations for pnfs_find_alloc_layout
   - Handle bad delegation stateids in nfs4_layoutget_handle_exception
   - Fix up O_DIRECT results
   - Fix potential use after free of state in nfs4_do_reclaim.
   - Mark the layout stateid invalid when all segments are removed
   - Don't let readdirplus revalidate an inode that was marked as stale
   - Fix potential race in nfs_fhget()
   - Fix an unused variable warning"

* tag 'nfs-for-4.7-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Fix another OPEN_DOWNGRADE bug
  make nfs_atomic_open() call d_drop() on all ->open_context() errors.
  NFS: Fix an unused variable warning
  NFS: Fix potential race in nfs_fhget()
  NFS: Don't let readdirplus revalidate an inode that was marked as stale
  NFSv4.1/pnfs: Mark the layout stateid invalid when all segments are removed
  NFS: Fix a double page unlock
  pnfs_nfs: fix _cancel_empty_pagelist
  nfs4: Fix potential use after free of state in nfs4_do_reclaim.
  NFS: Fix up O_DIRECT results
  NFS/pnfs: handle bad delegation stateids in nfs4_layoutget_handle_exception
  NFSv4.1/pnfs: Add sparse lock annotations for pnfs_find_alloc_layout
  NFSv4.1/pnfs: Layout stateids start out as being invalid
  NFSv4.1/pnfs: Ensure we handle delegation errors in nfs4_proc_layoutget()
2016-06-29 15:30:26 -07:00
Miklos Szeredi 03bea60409 ovl: get_write_access() in truncate
When truncating a file we should check write access on the underlying
inode.  And we should do so on the lower file as well (before copy-up) for
consistency.

Original patch and test case by Aihua Zhang.

 - - >o >o - - test.c - - >o >o - -
#include <stdio.h>
#include <errno.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
	int ret;

	ret = truncate(argv[0], 4096);
	if (ret != -1) {
		fprintf(stderr, "truncate(argv[0]) should have failed\n");
		return 1;
	}
	if (errno != ETXTBSY) {
		perror("truncate(argv[0])");
		return 1;
	}

	return 0;
}
 - - >o >o - - >o >o - - >o >o - -

Reported-by: Aihua Zhang <zhangaihua1@huawei.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-06-29 16:03:55 +02:00
Miklos Szeredi a4859d7594 ovl: fix dentry leak for default_permissions
When using the 'default_permissions' mount option, ovl_permission() on
non-directories was missing a dput(alias), resulting in "BUG Dentry still
in use".

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 8d3095f4ad ("ovl: default permissions")
Cc: <stable@vger.kernel.org> # v4.5+
2016-06-29 08:26:59 +02:00
Trond Myklebust e547f26283 NFS: Fix another OPEN_DOWNGRADE bug
Olga Kornievskaia reports that the following test fails to trigger
an OPEN_DOWNGRADE on the wire, and only triggers the final CLOSE.

	fd0 = open(foo, RDRW)   -- should be open on the wire for "both"
	fd1 = open(foo, RDONLY)  -- should be open on the wire for "read"
	close(fd0) -- should trigger an open_downgrade
	read(fd1)
	close(fd1)

The issue is that we're missing a check for whether or not the current
state transitioned from an O_RDWR state as opposed to having transitioned
from a combination of O_RDONLY and O_WRONLY.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: cd9288ffae ("NFSv4: Fix another bug in the close/open_downgrade code")
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-06-28 16:55:34 -04:00
Eric Sandeen 023954351f dax: fix offset overflow in dax_io
This isn't functionally apparent for some reason, but
when we test io at extreme offsets at the end of the loff_t
rang, such as in fstests xfs/071, the calculation of
"max" in dax_io() can be wrong due to pos + size overflowing.

For example,

# xfs_io -c "pwrite 9223372036854771712 512" /mnt/test/file

enters dax_io with:

start 0x7ffffffffffff000
end   0x7ffffffffffff200

and the rounded up "size" variable is 0x1000.  This yields:

pos + size 0x8000000000000000 (overflows loff_t)
       end 0x7ffffffffffff200

Due to the overflow, the min() function picks the wrong
value for the "max" variable, and when we send (max - pos)
into i.e. copy_from_iter_pmem() it is also the wrong value.

This somehow(tm) gets magically absorbed without incident,
probably because iter->count is correct.  But it seems best
to fix it up properly by comparing the two values as
unsigned.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-06-27 12:18:44 -07:00
Linus Torvalds fbe601f7a3 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
 "Various small cifs/smb3 fixes, include some for stable, and some from
  the recent SMB3 test event"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  File names with trailing period or space need special case conversion
  Fix reconnect to not defer smb3 session reconnect long after socket reconnect
  cifs: check hash calculating succeeded
  cifs: dynamic allocation of ntlmssp blob
  cifs: use CIFS_MAX_DOMAINNAME_LEN when converting the domain name
  cifs: stuff the fl_owner into "pid" field in the lock request
2016-06-27 11:23:44 -07:00
Al Viro d20cb71dbf make nfs_atomic_open() call d_drop() on all ->open_context() errors.
In "NFSv4: Move dentry instantiation into the NFSv4-specific atomic open code"
unconditional d_drop() after the ->open_context() had been removed.  It had
been correct for success cases (there ->open_context() itself had been doing
dcache manipulations), but not for error ones.  Only one of those (ENOENT)
got a compensatory d_drop() added in that commit, but in fact it should've
been done for all errors.  As it is, the case of O_CREAT non-exclusive open
on a hashed negative dentry racing with e.g. symlink creation from another
client ended up with ->open_context() getting an error and proceeding to
call nfs_lookup().  On a hashed dentry, which would've instantly triggered
BUG_ON() in d_materialise_unique() (or, these days, its equivalent in
d_splice_alias()).

Cc: stable@vger.kernel.org # v3.10+
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2016-06-27 08:59:08 -04:00
Linus Torvalds da2f6aba4a Merge branch 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes part 2 from Chris Mason:
 "This has one patch from Omar to bring iterate_shared back to btrfs.

  We have a tree of work we queue up for directory items and it doesn't
  lend itself well to shared access.  While we're cleaning it up, Omar
  has changed things to use an exclusive lock when there are delayed
  items"

* 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
2016-06-25 08:53:38 -07:00
Linus Torvalds b971712afc Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I have a two part pull this time because one of the patches Dave
  Sterba collected needed to be against v4.7-rc2 or higher (we used
  rc4).  I try to make my for-linus-xx branch testable on top of the
  last major so we can hand fixes to people on the list more easily, so
  I've split this pull in two.

  This first part has some fixes and two performance improvements that
  we've been testing for some time.

  Josef's two performance fixes are most notable.  The transid tracking
  patch makes a big improvement on pretty much every workload"

* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: Force stripesize to the value of sectorsize
  btrfs: fix disk_i_size update bug when fallocate() fails
  Btrfs: fix error handling in map_private_extent_buffer
  Btrfs: fix error return code in btrfs_init_test_fs()
  Btrfs: don't do nocow check unless we have to
  btrfs: fix deadlock in delayed_ref_async_start
  Btrfs: track transid for delayed ref flushing
2016-06-25 08:42:31 -07:00
Omar Sandoval 02dbfc99b4 Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
Commit fe742fd4f9 ("Revert "btrfs: switch to ->iterate_shared()"")
backed out the conversion to ->iterate_shared() for Btrfs because the
delayed inode handling in btrfs_real_readdir() is racy. However, we can
still do readdir in parallel if there are no delayed nodes.

This is a temporary fix which upgrades the shared inode lock to an
exclusive lock only when we have delayed items until we come up with a
more complete solution. While we're here, rename the
btrfs_{get,put}_delayed_items functions to make it very clear that
they're just for readdir.

Tested with xfstests and by doing a parallel kernel build:

	while make tinyconfig && make -j4 && git clean dqfx; do
		:
	done

along with a bunch of parallel finds in another shell:

	while true; do
		for ((i=0; i<4; i++)); do
			find . >/dev/null &
		done
		wait
	done

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2016-06-25 06:20:10 -07:00