Commit graph

135 commits

Author SHA1 Message Date
Tyler Hicks
8335eafc28 eCryptfs: Copy up attributes of the lower target inode after rename
After calling into the lower filesystem to do a rename, the lower target
inode's attributes were not copied up to the eCryptfs target inode. This
resulted in the eCryptfs target inode staying around, rather than being
evicted, because i_nlink was not updated for the eCryptfs inode. This
also meant that eCryptfs didn't do the final iput() on the lower target
inode so it stayed around, as well. This would result in a failure to
free up space occupied by the target file in the rename() operation.
Both target inodes would eventually be evicted when the eCryptfs
filesystem was unmounted.

This patch calls fsstack_copy_attr_all() after the lower filesystem
does its ->rename() so that important inode attributes, such as i_nlink,
are updated at the eCryptfs layer. ecryptfs_evict_inode() is now called
and eCryptfs can drop its final reference on the lower inode.

http://launchpad.net/bugs/561129

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Cc: <stable@vger.kernel.org> [2.6.39+]
2012-09-14 09:36:03 -07:00
Linus Torvalds
410fc4ce8a - Fixes a bug when the lower filesystem mount options include 'acl', but the
eCryptfs mount options do not
 - Cleanups in the messaging code
 - Better handling of empty files in the lower filesystem to improve usability.
   Failed file creations are now cleaned up and empty lower files are converted
   into eCryptfs during open().
 - The write-through cache changes are being reverted due to bugs that are not
   easy to fix. Stability outweighs the performance enhancements here.
 - Improvement to the mount code to catch unsupported ciphers specified in the
   mount options
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Merge tag 'ecryptfs-3.6-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull ecryptfs fixes from Tyler Hicks:
 - Fixes a bug when the lower filesystem mount options include 'acl',
   but the eCryptfs mount options do not
 - Cleanups in the messaging code
 - Better handling of empty files in the lower filesystem to improve
   usability.  Failed file creations are now cleaned up and empty lower
   files are converted into eCryptfs during open().
 - The write-through cache changes are being reverted due to bugs that
   are not easy to fix.  Stability outweighs the performance
   enhancements here.
 - Improvement to the mount code to catch unsupported ciphers specified
   in the mount options

* tag 'ecryptfs-3.6-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: check for eCryptfs cipher support at mount
  eCryptfs: Revert to a writethrough cache model
  eCryptfs: Initialize empty lower files when opening them
  eCryptfs: Unlink lower inode when ecryptfs_create() fails
  eCryptfs: Make all miscdev functions use daemon ptr in file private_data
  eCryptfs: Remove unused messaging declarations and function
  eCryptfs: Copy up POSIX ACL and read-only flags from lower mount
2012-08-02 10:56:34 -07:00
Al Viro
0b1d90119a ecryptfs_lookup_interpose(): allocate dentry_info first
less work on failure that way

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29 21:24:17 +04:00
Al Viro
bc65a1215e sanitize ecryptfs_lookup()
* ->lookup() never gets hit with . or ..
* dentry it gets is unhashed, so unless we had gone and hashed it ourselves, there's
no need to d_drop() the sucker.
* wrong name printed in one of the printks (NULL, in fact)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29 21:24:16 +04:00
Al Viro
8fc37ec54c don't expose I_NEW inodes via dentry->d_inode
d_instantiate(dentry, inode);
	unlock_new_inode(inode);

is a bad idea; do it the other way round...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-23 00:00:58 +04:00
Al Viro
312b63fba9 don't pass nameidata * to vfs_create()
all we want is a boolean flag, same as the method gets now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:50 +04:00
Al Viro
ebfc3b49a7 don't pass nameidata to ->create()
boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:47 +04:00
Al Viro
00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Tyler Hicks
821f7494a7 eCryptfs: Revert to a writethrough cache model
A change was made about a year ago to get eCryptfs to better utilize its
page cache during writes. The idea was to do the page encryption
operations during page writeback, rather than doing them when initially
writing into the page cache, to reduce the number of page encryption
operations during sequential writes. This meant that the encrypted page
would only be written to the lower filesystem during page writeback,
which was a change from how eCryptfs had previously wrote to the lower
filesystem in ecryptfs_write_end().

The change caused a few eCryptfs-internal bugs that were shook out.
Unfortunately, more grave side effects have been identified that will
force changes outside of eCryptfs. Because the lower filesystem isn't
consulted until page writeback, eCryptfs has no way to pass lower write
errors (ENOSPC, mainly) back to userspace. Additionaly, it was reported
that quotas could be bypassed because of the way eCryptfs may sometimes
open the lower filesystem using a privileged kthread.

It would be nice to resolve the latest issues, but it is best if the
eCryptfs commits be reverted to the old behavior in the meantime.

This reverts:
32001d6f "eCryptfs: Flush file in vma close"
5be79de2 "eCryptfs: Flush dirty pages in setattr"
57db4e8d "ecryptfs: modify write path to encrypt page in writepage"

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Tested-by: Colin King <colin.king@canonical.com>
Cc: Colin King <colin.king@canonical.com>
Cc: Thieu Le <thieule@google.com>
2012-07-13 16:46:06 -07:00
Tyler Hicks
e3ccaa9761 eCryptfs: Initialize empty lower files when opening them
Historically, eCryptfs has only initialized lower files in the
ecryptfs_create() path. Lower file initialization is the act of writing
the cryptographic metadata from the inode's crypt_stat to the header of
the file. The ecryptfs_open() path already expects that metadata to be
in the header of the file.

A number of users have reported empty lower files in beneath their
eCryptfs mounts. Most of the causes for those empty files being left
around have been addressed, but the presence of empty files causes
problems due to the lack of proper cryptographic metadata.

To transparently solve this problem, this patch initializes empty lower
files in the ecryptfs_open() error path. If the metadata is unreadable
due to the lower inode size being 0, plaintext passthrough support is
not in use, and the metadata is stored in the header of the file (as
opposed to the user.ecryptfs extended attribute), the lower file will be
initialized.

The number of nested conditionals in ecryptfs_open() was getting out of
hand, so a helper function was created. To avoid the same nested
conditional problem, the conditional logic was reversed inside of the
helper function.

https://launchpad.net/bugs/911507

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Colin Ian King <colin.king@canonical.com>
2012-07-08 12:51:45 -05:00
Tyler Hicks
8bc2d3cf61 eCryptfs: Unlink lower inode when ecryptfs_create() fails
ecryptfs_create() creates a lower inode, allocates an eCryptfs inode,
initializes the eCryptfs inode and cryptographic metadata attached to
the inode, and then writes the metadata to the header of the file.

If an error was to occur after the lower inode was created, an empty
lower file would be left in the lower filesystem. This is a problem
because ecryptfs_open() refuses to open any lower files which do not
have the appropriate metadata in the file header.

This patch properly unlinks the lower inode when an error occurs in the
later stages of ecryptfs_create(), reducing the chance that an empty
lower file will be left in the lower filesystem.

https://launchpad.net/bugs/872905

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Colin Ian King <colin.king@canonical.com>
2012-07-08 12:51:44 -05:00
Al Viro
408bd629ba get rid of pointless allocations and copying in ecryptfs_follow_link()
switch to generic_readlink(), while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29 23:28:40 -04:00
Tyler Hicks
545d680938 eCryptfs: Copy up lower inode attrs after setting lower xattr
After passing through a ->setxattr() call, eCryptfs needs to copy the
inode attributes from the lower inode to the eCryptfs inode, as they
may have changed in the lower filesystem's ->setxattr() path.

One example is if an extended attribute containing a POSIX Access
Control List is being set. The new ACL may cause the lower filesystem to
modify the mode of the lower inode and the eCryptfs inode would need to
be updated to reflect the new mode.

https://launchpad.net/bugs/926292

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Sebastien Bacher <seb128@ubuntu.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: <stable@vger.kernel.org>
2012-02-16 16:06:27 -06:00
Tyler Hicks
a261a03904 eCryptfs: Check inode changes in setattr
Most filesystems call inode_change_ok() very early in ->setattr(), but
eCryptfs didn't call it at all. It allowed the lower filesystem to make
the call in its ->setattr() function. Then, eCryptfs would copy the
appropriate inode attributes from the lower inode to the eCryptfs inode.

This patch changes that and actually calls inode_change_ok() on the
eCryptfs inode, fairly early in ecryptfs_setattr(). Ideally, the call
would happen earlier in ecryptfs_setattr(), but there are some possible
inode initialization steps that must happen first.

Since the call was already being made on the lower inode, the change in
functionality should be minimal, except for the case of a file extending
truncate call. In that case, inode_newsize_ok() was never being
called on the eCryptfs inode. Rather than inode_newsize_ok() catching
maximum file size errors early on, eCryptfs would encrypt zeroed pages
and write them to the lower filesystem until the lower filesystem's
write path caught the error in generic_write_checks(). This patch
introduces a new function, called ecryptfs_inode_newsize_ok(), which
checks if the new lower file size is within the appropriate limits when
the truncate operation will be growing the lower file.

In summary this change prevents eCryptfs truncate operations (and the
resulting page encryptions), which would exceed the lower filesystem
limits or FSIZE rlimits, from ever starting.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reviewed-by: Li Wang <liwang@nudt.edu.cn>
Cc: <stable@vger.kernel.org>
2012-01-25 14:43:41 -06:00
Al Viro
175a4eb7ea fs: propagate umode_t, misc bits
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:10 -05:00
Al Viro
18cb1b08d2 kill ecryptfs_create_underlying_file()
it's a just a wrapper for vfs_create()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:57 -05:00
Al Viro
1a67aafb5f switch ->mknod() to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:54 -05:00
Al Viro
4acdaf27eb switch ->create() to umode_t
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro
18bb1db3e7 switch vfs_mkdir() and ->mkdir() to umode_t
vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Tyler Hicks
b59db43ad4 eCryptfs: Prevent file create race condition
The file creation path prematurely called d_instantiate() and
unlock_new_inode() before the eCryptfs inode info was fully
allocated and initialized and before the eCryptfs metadata was written
to the lower file.

This could result in race conditions in subsequent file and inode
operations leading to unexpected error conditions or a null pointer
dereference while attempting to use the unallocated memory.

https://launchpad.net/bugs/813146

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Cc: stable@kernel.org
2011-11-23 15:39:38 -06:00
Miklos Szeredi
bfe8684869 filesystems: add set_nlink()
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-11-02 12:53:43 +01:00
Thieu Le
985ca0e626 ecryptfs: Make inode bdi consistent with superblock bdi
Make the inode mapping bdi consistent with the superblock bdi so that
dirty pages are flushed properly.

Signed-off-by: Thieu Le <thieule@chromium.org>
Cc: <stable@kernel.org> [2.6.39+]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-07-28 23:48:26 -05:00
Al Viro
bf6c7f6c7b don't pass nameidata to vfs_create() from ecryptfs_create()
Instead of playing with removal of LOOKUP_OPEN, mangling (and
restoring) nd->path, just pass NULL to vfs_create().  The whole
point of what's being done there is to suppress any attempts
to open file by underlying fs, which is what nd == NULL indicates.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:54 -04:00
Al Viro
beefebf1aa ecryptfs_inode_permission() doesn't need to bail out on RCU
... now that inode_permission() can take MAY_NOT_BLOCK and handle it
properly.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:38 -04:00
Al Viro
10556cb21a ->permission() sanitizing: don't pass flags to ->permission()
not used by the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:24 -04:00
Tyler Hicks
778aeb42a7 eCryptfs: Cleanup and optimize ecryptfs_lookup_interpose()
ecryptfs_lookup_interpose() has turned into spaghetti code over the
years. This is an effort to clean it up.

 - Shorten overly descriptive variable names such as ecryptfs_dentry
 - Simplify gotos and error paths
 - Create helper function for reading plaintext i_size from metadata

It also includes an optimization when reading i_size from the metadata.
A complete page-sized kmem_cache_alloc() was being done to read in 16
bytes of metadata. The buffer for that is now statically declared.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-05-29 14:24:24 -05:00
Tyler Hicks
3b06b3ebf4 eCryptfs: Fix new inode race condition
Only unlock and d_add() new inodes after the plaintext inode size has
been read from the lower filesystem. This fixes a race condition that
was sometimes seen during a multi-job kernel build in an eCryptfs mount.

https://bugzilla.kernel.org/show_bug.cgi?id=36002

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Reported-by: David <david@unsolicited.net>
Tested-by: David <david@unsolicited.net>
2011-05-29 14:23:39 -05:00
Tyler Hicks
5ccf92037c eCryptfs: Cleanup inode initialization code
The eCryptfs inode get, initialization, and dentry interposition code
has two separate paths. One is for when dentry interposition is needed
after doing things like a mkdir in the lower filesystem and the other
is needed after a lookup. Unlocking new inodes and doing a d_add() needs
to happen at different times, depending on which type of dentry
interposing is being done.

This patch cleans up the inode get and initialization code paths and
splits them up so that the locking and d_add() differences mentioned
above can be handled appropriately in a later patch.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Tested-by: David <david@unsolicited.net>
2011-05-29 12:51:17 -05:00
Tyler Hicks
c4f790736c eCryptfs: Consolidate inode functions into inode.c
These functions should live in inode.c since their focus is on inodes
and they're primarily used by functions in inode.c.

Also does a simple cleanup of ecryptfs_inode_test() and rolls
ecryptfs_init_inode() into ecryptfs_inode_set().

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Tested-by: David <david@unsolicited.net>
2011-05-29 12:49:53 -05:00
Linus Torvalds
36947a7682 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (36 commits)
  Cache xattr security drop check for write v2
  fs: block_page_mkwrite should wait for writeback to finish
  mm: Wait for writeback when grabbing pages to begin a write
  configfs: remove unnecessary dentry_unhash on rmdir, dir rename
  fat: remove unnecessary dentry_unhash on rmdir, dir rename
  hpfs: remove unnecessary dentry_unhash on rmdir, dir rename
  minix: remove unnecessary dentry_unhash on rmdir, dir rename
  fuse: remove unnecessary dentry_unhash on rmdir, dir rename
  coda: remove unnecessary dentry_unhash on rmdir, dir rename
  afs: remove unnecessary dentry_unhash on rmdir, dir rename
  affs: remove unnecessary dentry_unhash on rmdir, dir rename
  9p: remove unnecessary dentry_unhash on rmdir, dir rename
  ncpfs: fix rename over directory with dangling references
  ncpfs: document dentry_unhash usage
  ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename
  hostfs: remove unnecessary dentry_unhash on rmdir, dir rename
  hfsplus: remove unnecessary dentry_unhash on rmdir, dir rename
  hfs: remove unnecessary dentry_unhash on rmdir, dir rename
  omfs: remove unnecessary dentry_unhash on rmdir, dir rneame
  udf: remove unnecessary dentry_unhash from rmdir, dir rename
  ...
2011-05-28 13:03:41 -07:00
Sage Weil
55e5b7e022 ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename
ecryptfs does not have problems with references to unlinked directories.

CC: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
CC: Dustin Kirkland <kirkland@canonical.com>
CC: ecryptfs-devel@lists.launchpad.net
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-28 01:02:52 -04:00
Linus Torvalds
aaab184276 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ecryptfs/ecryptfs-2.6:
  MAINTAINERS: Update eCryptfs mailing list
  eCryptfs: Allow 2 scatterlist entries for encrypted filenames
  eCryptfs: Clear i_nlink in rmdir
2011-05-27 11:07:50 -07:00
Tyler Hicks
07850552b9 eCryptfs: Clear i_nlink in rmdir
eCryptfs wasn't clearing the eCryptfs inode's i_nlink after a successful
vfs_rmdir() on the lower directory. This resulted in the inode evict and
destroy paths to be missed.

https://bugs.launchpad.net/ecryptfs/+bug/723518

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
2011-05-27 11:46:14 -05:00
Sage Weil
e4eaac06bc vfs: push dentry_unhash on rename_dir into file systems
Only a few file systems need this.  Start by pushing it down into each
rename method (except gfs2 and xfs) so that it can be dealt with on a
per-fs basis.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26 07:26:48 -04:00
Sage Weil
79bf7c732b vfs: push dentry_unhash on rmdir into file systems
Only a few file systems need this.  Start by pushing it down into each
fs rmdir method (except gfs2 and xfs) so it can be dealt with on a per-fs
basis.

This does not change behavior for any in-tree file systems.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26 07:26:47 -04:00
Tyler Hicks
5be79de2e1 eCryptfs: Flush dirty pages in setattr
After 57db4e8d73 changed eCryptfs to
write-back caching, eCryptfs page writeback updates the lower inode
times due to the use of vfs_write() on the lower file.

To preserve inode metadata changes, such as 'cp -p' does with
utimensat(), we need to flush all dirty pages early in
ecryptfs_setattr() so that the user-updated lower inode metadata isn't
clobbered later in writeback.

https://bugzilla.kernel.org/show_bug.cgi?id=33372

Reported-by: Rocko <rockorequin@hotmail.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-04-25 18:49:46 -05:00
Tyler Hicks
3aeb86ea4c eCryptfs: Handle failed metadata read in lookup
When failing to read the lower file's crypto metadata during a lookup,
eCryptfs must continue on without throwing an error. For example, there
may be a plaintext file in the lower mount point that the user wants to
delete through the eCryptfs mount.

If an error is encountered while reading the metadata in lookup(), the
eCryptfs inode's size could be incorrect. We must be sure to reread the
plaintext inode size from the metadata when performing an open() or
setattr(). The metadata is already being read in those paths, so this
adds minimal performance overhead.

This patch introduces a flag which will track whether or not the
plaintext inode size has been read so that an incorrect i_size can be
fixed in the open() or setattr() paths.

https://bugs.launchpad.net/bugs/509180

Cc: <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-04-25 18:45:06 -05:00
Tyler Hicks
332ab16f83 eCryptfs: Add reference counting to lower files
For any given lower inode, eCryptfs keeps only one lower file open and
multiplexes all eCryptfs file operations through that lower file. The
lower file was considered "persistent" and stayed open from the first
lookup through the lifetime of the inode.

This patch keeps the notion of a single, per-inode lower file, but adds
reference counting around the lower file so that it is closed when not
currently in use. If the reference count is at 0 when an operation (such
as open, create, etc.) needs to use the lower file, a new lower file is
opened. Since the file is no longer persistent, all references to the
term persistent file are changed to lower file.

Locking is added around the sections of code that opens the lower file
and assign the pointer in the inode info, as well as the code the fputs
the lower file when all eCryptfs users are done with it.

This patch is needed to fix issues, when mounted on top of the NFSv3
client, where the lower file is left silly renamed until the eCryptfs
inode is destroyed.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-04-25 18:32:37 -05:00
Tyler Hicks
dd55c89852 eCryptfs: dput dentries returned from dget_parent
Call dput on the dentries previously returned by dget_parent() in
ecryptfs_rename(). This is needed for supported eCryptfs mounts on top
of the NFSv3 client.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-04-25 18:32:36 -05:00
Tyler Hicks
35ffa948b2 eCryptfs: Remove extra d_delete in ecryptfs_rmdir
vfs_rmdir() already calls d_delete() on the lower dentry. That was being
duplicated in ecryptfs_rmdir() and caused a NULL pointer dereference
when NFSv3 was the lower filesystem.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-04-25 18:32:35 -05:00
Tyler Hicks
fed8859b3a eCryptfs: Remove ECRYPTFS_NEW_FILE crypt stat flag
Now that grow_file() is not called in the ecryptfs_create() path, the
ECRYPTFS_NEW_FILE flag is no longer needed. It helped
ecryptfs_readpage() know not to decrypt zeroes that were read from the
lower file in the grow_file() path.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-03-28 01:47:44 -05:00
Tyler Hicks
bd4f0fe8bb eCryptfs: Remove unnecessary grow_file() function
When creating a new eCryptfs file, the crypto metadata is written out
and then the lower file was being "grown" with 4 kB of encrypted zeroes.
I suspect that growing the encrypted file was to prevent an information
leak that the unencrypted file was empty. However, the unencrypted file
size is stored, in plaintext, in the metadata so growing the file is
unnecessary.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-03-28 01:47:43 -05:00
Tyler Hicks
55f9cf6bba eCryptfs: Copy up lower inode attrs in getattr
The lower filesystem may do some type of inode revalidation during a
getattr call. eCryptfs should take advantage of that by copying the
lower inode attributes to the eCryptfs inode after a call to
vfs_getattr() on the lower inode.

I originally wrote this fix while working on eCryptfs on nfsv3 support,
but discovered it also fixed an eCryptfs on ext4 nanosecond timestamp
bug that was reported.

https://bugs.launchpad.net/bugs/613873

Cc: <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-02-21 14:46:36 -06:00
Tyler Hicks
70b8902199 eCryptfs: Handle NULL nameidata pointers
Allow for NULL nameidata pointers in eCryptfs create, lookup, and
d_revalidate functions.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-02-21 14:45:57 -06:00
Tyler Hicks
8787c7a3e0 eCryptfs: Revert "dont call lookup_one_len to avoid NULL nameidata"
This reverts commit 21edad3220 and commit
93c3fe40c2, which fixed a regression by
the former.

Al Viro pointed out bypassed dcache lookups in
ecryptfs_new_lower_dentry(), misuse of vfs_path_lookup() in
ecryptfs_lookup_one_lower() and a dislike of passing nameidata to the
lower filesystem.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-02-17 20:30:29 -06:00
Roberto Sassu
27992890b0 ecryptfs: test lower_file pointer when lower_file_mutex is locked
This patch prevents the lower_file pointer in the 'ecryptfs_inode_info'
structure to be checked when the mutex 'lower_file_mutex' is not locked.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-01-17 11:24:42 -06:00
Al Viro
66cb76666d sanitize ecryptfs ->mount()
kill ecryptfs_read_super(), reorder code allowing to use
normal d_alloc_root() instead of opencoding it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:04:37 -05:00
Nick Piggin
b74c79e993 fs: provide rcu-walk aware permission i_ops
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin
fb045adb99 fs: dcache reduce branches in lookup path
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:28 +11:00
Nick Piggin
b7ab39f631 fs: dcache scale dentry refcount
Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
we start protecting many other dentry members with d_lock.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:21 +11:00