Commit Graph

82 Commits

Author SHA1 Message Date
Tyler Hicks f24b38874e ecryptfs: Fix ecryptfs_printk() size_t warnings
Commit cb55d21f6fa19d8c6c2680d90317ce88c1f57269 revealed a number of
missing 'z' length modifiers in calls to ecryptfs_printk() when
printing variables of type size_t. This patch fixes those compiler
warnings.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-01-17 13:01:24 -06:00
Joe Perches 888d57bbc9 fs/ecryptfs: Add printf format/argument verification and fix fallout
Add __attribute__((format... to __ecryptfs_printk
Make formats and arguments match.
Add casts to (unsigned long long) for %llu.

Signed-off-by: Joe Perches <joe@perches.com>
[tyhicks: 80 columns cleanup and fixed typo]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2011-01-17 13:01:23 -06:00
Tyler Hicks 93c3fe40c2 eCryptfs: Fix encrypted file name lookup regression
Fixes a regression caused by 21edad3220

When file name encryption was enabled, ecryptfs_lookup() failed to use
the encrypted and encoded version of the upper, plaintext, file name
when performing a lookup in the lower file system. This made it
impossible to lookup existing encrypted file names and any newly created
files would have plaintext file names in the lower file system.

https://bugs.launchpad.net/ecryptfs/+bug/623087

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-08-27 10:50:53 -05:00
Jerome Marchand 7371a38201 ecryptfs: properly mark init functions
Some ecryptfs init functions are not prefixed by __init and thus not
freed after initialization. This patch saved about 1kB in ecryptfs
module.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-08-27 10:50:52 -05:00
Uwe Kleine-König 421f91d21a fix typos concerning "initiali[zs]e"
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-06-16 18:05:05 +02:00
Linus Torvalds 9b030e2006 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:
  eCryptfs: Turn lower lookup error messages into debug messages
  eCryptfs: Copy lower directory inode times and size on link
  ecryptfs: fix use with tmpfs by removing d_drop from ecryptfs_destroy_inode
  ecryptfs: fix error code for missing xattrs in lower fs
  eCryptfs: Decrypt symlink target for stat size
  eCryptfs: Strip metadata in xattr flag in encrypted view
  eCryptfs: Clear buffer before reading in metadata xattr
  eCryptfs: Rename ecryptfs_crypt_stat.num_header_bytes_at_front
  eCryptfs: Fix metadata in xattr feature regression
2010-04-19 14:20:32 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Tyler Hicks f4e60e6b30 eCryptfs: Strip metadata in xattr flag in encrypted view
The ecryptfs_encrypted_view mount option provides a unified way of
viewing encrypted eCryptfs files.  If the metadata is stored in a xattr,
the metadata is moved to the file header when the file is read inside
the eCryptfs mount.  Because of this, we should strip the
ECRYPTFS_METADATA_IN_XATTR flag from the header's flag section.  This
allows eCryptfs to treat the file as an eCryptfs file with a header
at the front.

Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-03-23 12:31:35 -05:00
Tyler Hicks 1984c23f9e eCryptfs: Clear buffer before reading in metadata xattr
We initially read in the first PAGE_CACHE_SIZE of a file to if the
eCryptfs header marker can be found.  If it isn't found and
ecryptfs_xattr_metadata was given as a mount option, then the
user.ecryptfs xattr is read into the same buffer.  Since the data from
the first page of the file wasn't cleared, it is possible that we think
we've found a second tag 3 or tag 1 packet and then error out after the
packet contents aren't as expected.  This patch clears the buffer before
filling it with metadata from the user.ecryptfs xattr.

Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-03-23 12:31:09 -05:00
Tyler Hicks fa3ef1cb4e eCryptfs: Rename ecryptfs_crypt_stat.num_header_bytes_at_front
This patch renames the num_header_bytes_at_front variable to
metadata_size since it now contains the max size of the metadata.

Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-03-23 12:30:41 -05:00
Tyler Hicks 157f107135 eCryptfs: Fix metadata in xattr feature regression
Fixes regression in 8faece5f90

When using the ecryptfs_xattr_metadata mount option, eCryptfs stores the
metadata (normally stored at the front of the file) in the user.ecryptfs
xattr.  This causes ecryptfs_crypt_stat.num_header_bytes_at_front to be
0, since there is no header data at the front of the file.  This results
in too much memory being requested and ENOMEM being returned from
ecryptfs_write_metadata().

This patch fixes the problem by using the num_header_bytes_at_front
variable for specifying the max size of the metadata, despite whether it
is stored in the header or xattr.

Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-03-23 12:29:49 -05:00
Dan Carpenter ece550f51b ecryptfs: use after free
The "full_alg_name" variable is used on a couple error paths, so we
shouldn't free it until the end.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19 22:36:06 -06:00
Tyler Hicks 96a7b9c2f5 eCryptfs: Propagate vfs_read and vfs_write return codes
Errors returned from vfs_read() and vfs_write() calls to the lower
filesystem were being masked as -EINVAL.  This caused some confusion to
users who saw EINVAL instead of ENOSPC when the disk was full, for
instance.

Also, the actual bytes read or written were not accessible by callers to
ecryptfs_read_lower() and ecryptfs_write_lower(), which may be useful in
some cases.  This patch updates the error handling logic where those
functions are called in order to accept positive return codes indicating
success.

Cc: Eric Sandeen <esandeen@redhat.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: ecryptfs-devel@lists.launchpad.net
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:34 -05:00
Tyler Hicks df6ad33ba1 eCryptfs: Filename encryption only supports password auth tokens
Returns -ENOTSUPP when attempting to use filename encryption with
something other than a password authentication token, such as a private
token from openssl.  Using filename encryption with a userspace eCryptfs
key module is a future goal.  Until then, this patch handles the
situation a little better than simply using a BUG_ON().

Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: ecryptfs-devel@lists.launchpad.net
Cc: stable <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:32 -05:00
Tyler Hicks b0105eaefa eCryptfs: Handle unrecognized tag 3 cipher codes
Returns an error when an unrecognized cipher code is present in a tag 3
packet or an ecryptfs_crypt_stat cannot be initialized.  Also sets an
crypt_stat->tfm error pointer to NULL to ensure that it will not be
incorrectly freed in ecryptfs_destroy_crypt_stat().

Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: ecryptfs-devel@lists.launchpad.net
Cc: stable <stable@kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:31 -05:00
Dave Hansen 382684984e ecryptfs: improved dependency checking and reporting
So, I compiled a 2.6.31-rc5 kernel with ecryptfs and loaded its module.
When it came time to mount my filesystem, I got this in dmesg, and it
refused to mount:

[93577.776637] Unable to allocate crypto cipher with name [aes]; rc = [-2]
[93577.783280] Error attempting to initialize key TFM cipher with name = [aes]; rc = [-2]
[93577.791183] Error attempting to initialize cipher with name = [aes] and key size = [32]; rc = [-2]
[93577.800113] Error parsing options; rc = [-22]

I figured from the error message that I'd either forgotten to load "aes"
or that my key size was bogus.  Neither one of those was the case.  In
fact, I was missing the CRYPTO_ECB config option and the 'ecb' module.
Unfortunately, there's no trace of 'ecb' in that error message.

I've done two things to fix this.  First, I've modified ecryptfs's
Kconfig entry to select CRYPTO_ECB and CRYPTO_CBC.  I also took CRYPTO
out of the dependencies since the 'select' will take care of it for us.

I've also modified the error messages to print a string that should
contain both 'ecb' and 'aes' in my error case.  That will give any
future users a chance of finding the right modules and Kconfig options.

I also wonder if we should:

	select CRYPTO_AES if !EMBEDDED

since I think most ecryptfs users are using AES like me.

Cc: ecryptfs-devel@lists.launchpad.net
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Dustin Kirkland <kirkland@canonical.com>
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
[tyhicks@linux.vnet.ibm.com: Removed extra newline, 80-char violation]
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:31 -05:00
Roland Dreier aa06117f19 eCryptfs: Fix lockdep-reported AB-BA mutex issue
Lockdep reports the following valid-looking possible AB-BA deadlock with
global_auth_tok_list_mutex and keysig_list_mutex:

  ecryptfs_new_file_context() ->
      ecryptfs_copy_mount_wide_sigs_to_inode_sigs() ->
          mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
          -> ecryptfs_add_keysig() ->
              mutex_lock(&crypt_stat->keysig_list_mutex);

vs

  ecryptfs_generate_key_packet_set() ->
      mutex_lock(&crypt_stat->keysig_list_mutex);
      -> ecryptfs_find_global_auth_tok_for_sig() ->
          mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);

ie the two mutexes are taken in opposite orders in the two different
code paths.  I'm not sure if this is a real bug where two threads could
actually hit the two paths in parallel and deadlock, but it at least
makes lockdep impossible to use with ecryptfs since this report triggers
every time and disables future lockdep reporting.

Since ecryptfs_add_keysig() is called only from the single callsite in
ecryptfs_copy_mount_wide_sigs_to_inode_sigs(), the simplest fix seems to
be to move the lock of keysig_list_mutex back up outside of the where
global_auth_tok_list_mutex is taken.  This patch does that, and fixes
the lockdep report on my system (and ecryptfs still works OK).

The full output of lockdep fixed by this patch is:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.31-2-generic #14~rbd2
-------------------------------------------------------
gdm/2640 is trying to acquire lock:
 (&mount_crypt_stat->global_auth_tok_list_mutex){+.+.+.}, at: [<ffffffff8121591e>] ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90

but task is already holding lock:
 (&crypt_stat->keysig_list_mutex){+.+.+.}, at: [<ffffffff81217728>] ecryptfs_generate_key_packet_set+0x58/0x2b0

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&crypt_stat->keysig_list_mutex){+.+.+.}:
       [<ffffffff8108c897>] check_prev_add+0x2a7/0x370
       [<ffffffff8108cfc1>] validate_chain+0x661/0x750
       [<ffffffff8108d2e7>] __lock_acquire+0x237/0x430
       [<ffffffff8108d585>] lock_acquire+0xa5/0x150
       [<ffffffff815526cd>] __mutex_lock_common+0x4d/0x3d0
       [<ffffffff81552b56>] mutex_lock_nested+0x46/0x60
       [<ffffffff8121526a>] ecryptfs_add_keysig+0x5a/0xb0
       [<ffffffff81213299>] ecryptfs_copy_mount_wide_sigs_to_inode_sigs+0x59/0xb0
       [<ffffffff81214b06>] ecryptfs_new_file_context+0xa6/0x1a0
       [<ffffffff8120e42a>] ecryptfs_initialize_file+0x4a/0x140
       [<ffffffff8120e54d>] ecryptfs_create+0x2d/0x60
       [<ffffffff8113a7d4>] vfs_create+0xb4/0xe0
       [<ffffffff8113a8c4>] __open_namei_create+0xc4/0x110
       [<ffffffff8113d1c1>] do_filp_open+0xa01/0xae0
       [<ffffffff8112d8d9>] do_sys_open+0x69/0x140
       [<ffffffff8112d9f0>] sys_open+0x20/0x30
       [<ffffffff81013132>] system_call_fastpath+0x16/0x1b
       [<ffffffffffffffff>] 0xffffffffffffffff

-> #0 (&mount_crypt_stat->global_auth_tok_list_mutex){+.+.+.}:
       [<ffffffff8108c675>] check_prev_add+0x85/0x370
       [<ffffffff8108cfc1>] validate_chain+0x661/0x750
       [<ffffffff8108d2e7>] __lock_acquire+0x237/0x430
       [<ffffffff8108d585>] lock_acquire+0xa5/0x150
       [<ffffffff815526cd>] __mutex_lock_common+0x4d/0x3d0
       [<ffffffff81552b56>] mutex_lock_nested+0x46/0x60
       [<ffffffff8121591e>] ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90
       [<ffffffff812177d5>] ecryptfs_generate_key_packet_set+0x105/0x2b0
       [<ffffffff81212f49>] ecryptfs_write_headers_virt+0xc9/0x120
       [<ffffffff8121306d>] ecryptfs_write_metadata+0xcd/0x200
       [<ffffffff8120e44b>] ecryptfs_initialize_file+0x6b/0x140
       [<ffffffff8120e54d>] ecryptfs_create+0x2d/0x60
       [<ffffffff8113a7d4>] vfs_create+0xb4/0xe0
       [<ffffffff8113a8c4>] __open_namei_create+0xc4/0x110
       [<ffffffff8113d1c1>] do_filp_open+0xa01/0xae0
       [<ffffffff8112d8d9>] do_sys_open+0x69/0x140
       [<ffffffff8112d9f0>] sys_open+0x20/0x30
       [<ffffffff81013132>] system_call_fastpath+0x16/0x1b
       [<ffffffffffffffff>] 0xffffffffffffffff

other info that might help us debug this:

2 locks held by gdm/2640:
 #0:  (&sb->s_type->i_mutex_key#11){+.+.+.}, at: [<ffffffff8113cb8b>] do_filp_open+0x3cb/0xae0
 #1:  (&crypt_stat->keysig_list_mutex){+.+.+.}, at: [<ffffffff81217728>] ecryptfs_generate_key_packet_set+0x58/0x2b0

stack backtrace:
Pid: 2640, comm: gdm Tainted: G         C 2.6.31-2-generic #14~rbd2
Call Trace:
 [<ffffffff8108b988>] print_circular_bug_tail+0xa8/0xf0
 [<ffffffff8108c675>] check_prev_add+0x85/0x370
 [<ffffffff81094912>] ? __module_text_address+0x12/0x60
 [<ffffffff8108cfc1>] validate_chain+0x661/0x750
 [<ffffffff81017275>] ? print_context_stack+0x85/0x140
 [<ffffffff81089c68>] ? find_usage_backwards+0x38/0x160
 [<ffffffff8108d2e7>] __lock_acquire+0x237/0x430
 [<ffffffff8108d585>] lock_acquire+0xa5/0x150
 [<ffffffff8121591e>] ? ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90
 [<ffffffff8108b0b0>] ? check_usage_backwards+0x0/0xb0
 [<ffffffff815526cd>] __mutex_lock_common+0x4d/0x3d0
 [<ffffffff8121591e>] ? ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90
 [<ffffffff8121591e>] ? ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90
 [<ffffffff8108c02c>] ? mark_held_locks+0x6c/0xa0
 [<ffffffff81125b0d>] ? kmem_cache_alloc+0xfd/0x1a0
 [<ffffffff8108c34d>] ? trace_hardirqs_on_caller+0x14d/0x190
 [<ffffffff81552b56>] mutex_lock_nested+0x46/0x60
 [<ffffffff8121591e>] ecryptfs_find_global_auth_tok_for_sig+0x2e/0x90
 [<ffffffff812177d5>] ecryptfs_generate_key_packet_set+0x105/0x2b0
 [<ffffffff81212f49>] ecryptfs_write_headers_virt+0xc9/0x120
 [<ffffffff8121306d>] ecryptfs_write_metadata+0xcd/0x200
 [<ffffffff81210240>] ? ecryptfs_init_persistent_file+0x60/0xe0
 [<ffffffff8120e44b>] ecryptfs_initialize_file+0x6b/0x140
 [<ffffffff8120e54d>] ecryptfs_create+0x2d/0x60
 [<ffffffff8113a7d4>] vfs_create+0xb4/0xe0
 [<ffffffff8113a8c4>] __open_namei_create+0xc4/0x110
 [<ffffffff8113d1c1>] do_filp_open+0xa01/0xae0
 [<ffffffff8129a93e>] ? _raw_spin_unlock+0x5e/0xb0
 [<ffffffff8155410b>] ? _spin_unlock+0x2b/0x40
 [<ffffffff81139e9b>] ? getname+0x3b/0x240
 [<ffffffff81148a5a>] ? alloc_fd+0xfa/0x140
 [<ffffffff8112d8d9>] do_sys_open+0x69/0x140
 [<ffffffff81553b8f>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff8112d9f0>] sys_open+0x20/0x30
 [<ffffffff81013132>] system_call_fastpath+0x16/0x1b

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:30 -05:00
Roland Dreier 05dafedb90 ecryptfs: Remove unneeded locking that triggers lockdep false positives
In ecryptfs_destroy_inode(), inode_info->lower_file_mutex is locked,
and just after the mutex is unlocked, the code does:

 	kmem_cache_free(ecryptfs_inode_info_cache, inode_info);

This means that if another context could possibly try to take the same
mutex as ecryptfs_destroy_inode(), then it could end up getting the
mutex just before the data structure containing the mutex is freed.
So any such use would be an obvious use-after-free bug (catchable with
slab poisoning or mutex debugging), and therefore the locking in
ecryptfs_destroy_inode() is not needed and can be dropped.

Similarly, in ecryptfs_destroy_crypt_stat(), crypt_stat->keysig_list_mutex
is locked, and then the mutex is unlocked just before the code does:

 	memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));

Therefore taking this mutex is similarly not necessary.

Removing this locking fixes false-positive lockdep reports such as the
following (and they are false-positives for exactly the same reason
that the locking is not needed):

=================================
[ INFO: inconsistent lock state ]
2.6.31-2-generic #14~rbd3
---------------------------------
inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
kswapd0/323 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&inode_info->lower_file_mutex){+.+.?.}, at: [<ffffffff81210d34>] ecryptfs_destroy_inode+0x34/0x100
{RECLAIM_FS-ON-W} state was registered at:
  [<ffffffff8108c02c>] mark_held_locks+0x6c/0xa0
  [<ffffffff8108c10f>] lockdep_trace_alloc+0xaf/0xe0
  [<ffffffff81125a51>] kmem_cache_alloc+0x41/0x1a0
  [<ffffffff8113117a>] get_empty_filp+0x7a/0x1a0
  [<ffffffff8112dd46>] dentry_open+0x36/0xc0
  [<ffffffff8121a36c>] ecryptfs_privileged_open+0x5c/0x2e0
  [<ffffffff81210283>] ecryptfs_init_persistent_file+0xa3/0xe0
  [<ffffffff8120e838>] ecryptfs_lookup_and_interpose_lower+0x278/0x380
  [<ffffffff8120f97a>] ecryptfs_lookup+0x12a/0x250
  [<ffffffff8113930a>] real_lookup+0xea/0x160
  [<ffffffff8113afc8>] do_lookup+0xb8/0xf0
  [<ffffffff8113b518>] __link_path_walk+0x518/0x870
  [<ffffffff8113bd9c>] path_walk+0x5c/0xc0
  [<ffffffff8113be5b>] do_path_lookup+0x5b/0xa0
  [<ffffffff8113bfe7>] user_path_at+0x57/0xa0
  [<ffffffff811340dc>] vfs_fstatat+0x3c/0x80
  [<ffffffff8113424b>] vfs_stat+0x1b/0x20
  [<ffffffff81134274>] sys_newstat+0x24/0x50
  [<ffffffff81013132>] system_call_fastpath+0x16/0x1b
  [<ffffffffffffffff>] 0xffffffffffffffff
irq event stamp: 7811
hardirqs last  enabled at (7811): [<ffffffff810c037f>] call_rcu+0x5f/0x90
hardirqs last disabled at (7810): [<ffffffff810c0353>] call_rcu+0x33/0x90
softirqs last  enabled at (3764): [<ffffffff810631da>] __do_softirq+0x14a/0x220
softirqs last disabled at (3751): [<ffffffff8101440c>] call_softirq+0x1c/0x30

other info that might help us debug this:
2 locks held by kswapd0/323:
 #0:  (shrinker_rwsem){++++..}, at: [<ffffffff810f67ed>] shrink_slab+0x3d/0x190
 #1:  (&type->s_umount_key#35){.+.+..}, at: [<ffffffff811429a1>] prune_dcache+0xd1/0x1b0

stack backtrace:
Pid: 323, comm: kswapd0 Tainted: G         C 2.6.31-2-generic #14~rbd3
Call Trace:
 [<ffffffff8108ad6c>] print_usage_bug+0x18c/0x1a0
 [<ffffffff8108aff0>] ? check_usage_forwards+0x0/0xc0
 [<ffffffff8108bac2>] mark_lock_irq+0xf2/0x280
 [<ffffffff8108bd87>] mark_lock+0x137/0x1d0
 [<ffffffff81164710>] ? fsnotify_clear_marks_by_inode+0x30/0xf0
 [<ffffffff8108bee6>] mark_irqflags+0xc6/0x1a0
 [<ffffffff8108d337>] __lock_acquire+0x287/0x430
 [<ffffffff8108d585>] lock_acquire+0xa5/0x150
 [<ffffffff81210d34>] ? ecryptfs_destroy_inode+0x34/0x100
 [<ffffffff8108d2e7>] ? __lock_acquire+0x237/0x430
 [<ffffffff815526ad>] __mutex_lock_common+0x4d/0x3d0
 [<ffffffff81210d34>] ? ecryptfs_destroy_inode+0x34/0x100
 [<ffffffff81164710>] ? fsnotify_clear_marks_by_inode+0x30/0xf0
 [<ffffffff81210d34>] ? ecryptfs_destroy_inode+0x34/0x100
 [<ffffffff8129a91e>] ? _raw_spin_unlock+0x5e/0xb0
 [<ffffffff81552b36>] mutex_lock_nested+0x46/0x60
 [<ffffffff81210d34>] ecryptfs_destroy_inode+0x34/0x100
 [<ffffffff81145d27>] destroy_inode+0x87/0xd0
 [<ffffffff81146b4c>] generic_delete_inode+0x12c/0x1a0
 [<ffffffff81145832>] iput+0x62/0x70
 [<ffffffff811423c8>] dentry_iput+0x98/0x110
 [<ffffffff81142550>] d_kill+0x50/0x80
 [<ffffffff81142623>] prune_one_dentry+0xa3/0xc0
 [<ffffffff811428b1>] __shrink_dcache_sb+0x271/0x290
 [<ffffffff811429d9>] prune_dcache+0x109/0x1b0
 [<ffffffff81142abf>] shrink_dcache_memory+0x3f/0x50
 [<ffffffff810f68dd>] shrink_slab+0x12d/0x190
 [<ffffffff810f9377>] balance_pgdat+0x4d7/0x640
 [<ffffffff8104c4c0>] ? finish_task_switch+0x40/0x150
 [<ffffffff810f63c0>] ? isolate_pages_global+0x0/0x60
 [<ffffffff810f95f7>] kswapd+0x117/0x170
 [<ffffffff810777a0>] ? autoremove_wake_function+0x0/0x40
 [<ffffffff810f94e0>] ? kswapd+0x0/0x170
 [<ffffffff810773be>] kthread+0x9e/0xb0
 [<ffffffff8101430a>] child_rip+0xa/0x20
 [<ffffffff81013c90>] ? restore_args+0x0/0x30
 [<ffffffff81077320>] ? kthread+0x0/0xb0
 [<ffffffff81014300>] ? child_rip+0x0/0x20

Signed-off-by: Roland Dreier <roland@digitalvampire.org>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23 09:10:30 -05:00
Tyler Hicks 13a791b4e6 eCryptfs: Fix data corruption when using ecryptfs_passthrough
ecryptfs_passthrough is a mount option that allows eCryptfs to allow
data to be written to non-eCryptfs files in the lower filesystem.  The
passthrough option was causing data corruption due to it not always
being treated as a non-eCryptfs file.

The first 8 bytes of an eCryptfs file contains the decrypted file size.
This value was being written to the non-eCryptfs files, too.  Also,
extra 0x00 characters were being written to make the file size a
multiple of PAGE_CACHE_SIZE.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22 03:54:13 -05:00
Tyler Hicks 2aac0cf886 eCryptfs: NULL crypt_stat dereference during lookup
If ecryptfs_encrypted_view or ecryptfs_xattr_metadata were being
specified as mount options, a NULL pointer dereference of crypt_stat
was possible during lookup.

This patch moves the crypt_stat assignment into
ecryptfs_lookup_and_interpose_lower(), ensuring that crypt_stat
will not be NULL before we attempt to dereference it.

Thanks to Dan Carpenter and his static analysis tool, smatch, for
finding this bug.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-22 11:20:43 -07:00
Tyler Hicks 8faece5f90 eCryptfs: Allocate a variable number of pages for file headers
When allocating the memory used to store the eCryptfs header contents, a
single, zeroed page was being allocated with get_zeroed_page().
However, the size of an eCryptfs header is either PAGE_CACHE_SIZE or
ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE (8192), whichever is larger, and is
stored in the file's private_data->crypt_stat->num_header_bytes_at_front
field.

ecryptfs_write_metadata_to_contents() was using
num_header_bytes_at_front to decide how many bytes should be written to
the lower filesystem for the file header.  Unfortunately, at least 8K
was being written from the page, despite the chance of the single,
zeroed page being smaller than 8K.  This resulted in random areas of
kernel memory being written between the 0x1000 and 0x1FFF bytes offsets
in the eCryptfs file headers if PAGE_SIZE was 4K.

This patch allocates a variable number of pages, calculated with
num_header_bytes_at_front, and passes the number of allocated pages
along to ecryptfs_write_metadata_to_contents().

Thanks to Florian Streibelt for reporting the data leak and working with
me to find the problem.  2.6.28 is the only kernel release with this
vulnerability.  Corresponds to CVE-2009-0787

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Eugene Teo <eugeneteo@kernel.sg>
Cc: Greg KH <greg@kroah.com>
Cc: dann frazier <dannf@dannf.org>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Florian Streibelt <florian@f-streibelt.de>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-22 11:20:43 -07:00
Tyler Hicks 84814d642a eCryptfs: don't encrypt file key with filename key
eCryptfs has file encryption keys (FEK), file encryption key encryption
keys (FEKEK), and filename encryption keys (FNEK).  The per-file FEK is
encrypted with one or more FEKEKs and stored in the header of the
encrypted file.  I noticed that the FEK is also being encrypted by the
FNEK.  This is a problem if a user wants to use a different FNEK than
their FEKEK, as their file contents will still be accessible with the
FNEK.

This is a minimalistic patch which prevents the FNEKs signatures from
being copied to the inode signatures list.  Ultimately, it keeps the FEK
from being encrypted with a FNEK.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Acked-by: Dustin Kirkland <kirkland@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-14 11:57:22 -07:00
Tyler Hicks fd9fc842bb eCryptfs: Regression in unencrypted filename symlinks
The addition of filename encryption caused a regression in unencrypted
filename symlink support.  ecryptfs_copy_filename() is used when dealing
with unencrypted filenames and it reported that the new, copied filename
was a character longer than it should have been.

This caused the return value of readlink() to count the NULL byte of the
symlink target.  Most applications don't care about the extra NULL byte,
but a version control system (bzr) helped in discovering the bug.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-06 18:36:40 -08:00
Michael Halcrow 71c11c378f eCryptfs: Clean up ecryptfs_decode_from_filename()
Flesh out the comments for ecryptfs_decode_from_filename(). Remove the
return condition, since it is always 0.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Dustin Kirkland <dustin.kirkland@gmail.com>
Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Tyler Hicks <tchicks@us.ibm.com>
Cc: David Kleikamp <shaggy@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:22 -08:00
Michael Halcrow a8f12864c5 eCryptfs: Fix data types (int/size_t)
Correct several format string data type specifiers.  Correct filename size
data types; they should be size_t rather than int when passed as
parameters to some other functions (although note that the filenames will
never be larger than int).

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Dustin Kirkland <dustin.kirkland@gmail.com>
Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Tyler Hicks <tchicks@us.ibm.com>
Cc: David Kleikamp <shaggy@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:22 -08:00