linux-stable.git/fs/ecryptfs/main.c, branch linux-3.4.y

eCryptfs: Force RO mount when encrypted view is enabled

2015-04-14T09:33:40+00:00

commit 332b122d39c9cbff8b799007a825d94b2e7c12f2 upstream.

The ecryptfs_encrypted_view mount option greatly changes the
functionality of an eCryptfs mount. Instead of encrypting and decrypting
lower files, it provides a unified view of the encrypted files in the
lower filesystem. The presence of the ecryptfs_encrypted_view mount
option is intended to force a read-only mount and modifying files is not
supported when the feature is in use. See the following commit for more
information:

  e77a56d [PATCH] eCryptfs: Encrypted passthrough

This patch forces the mount to be read-only when the
ecryptfs_encrypted_view mount option is specified by setting the
MS_RDONLY flag on the superblock. Additionally, this patch removes some
broken logic in ecryptfs_open() that attempted to prevent modifications
of files when the encrypted view feature was in use. The check in
ecryptfs_open() was not sufficient to prevent file modifications using
system calls that do not operate on a file descriptor.

Signed-off-by: Tyler Hicks 
Reported-by: Priya Bansal 
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li

eCryptfs: check for eCryptfs cipher support at mount

2012-11-26T19:37:49+00:00

commit 5f5b331d5c21228a6519dcb793fc1629646c51a6 upstream.

The issue occurs when eCryptfs is mounted with a cipher supported by
the crypto subsystem but not by eCryptfs. The mount succeeds and an
error does not occur until a write. This change checks for eCryptfs
cipher support at mount time.

Resolves Launchpad issue #338914, reported by Tyler Hicks in 03/2009.
https://bugs.launchpad.net/ecryptfs/+bug/338914

Signed-off-by: Tim Sally 
Signed-off-by: Tyler Hicks 
Cc: Herton Ronaldo Krzesinski 
Signed-off-by: Greg Kroah-Hartman

eCryptfs: Copy up POSIX ACL and read-only flags from lower mount

2012-11-26T19:37:49+00:00

commit 069ddcda37b2cf5bb4b6031a944c0e9359213262 upstream.

When the eCryptfs mount options do not include '-o acl', but the lower
filesystem's mount options do include 'acl', the MS_POSIXACL flag is not
flipped on in the eCryptfs super block flags. This flag is what the VFS
checks in do_last() when deciding if the current umask should be applied
to a newly created inode's mode or not. When a default POSIX ACL mask is
set on a directory, the current umask is incorrectly applied to new
inodes created in the directory. This patch ignores the MS_POSIXACL flag
passed into ecryptfs_mount() and sets the flag on the eCryptfs super
block depending on the flag's presence on the lower super block.

Additionally, it is incorrect to allow a writeable eCryptfs mount on top
of a read-only lower mount. This missing check did not allow writes to
the read-only lower mount because permissions checks are still performed
on the lower filesystem's objects but it is best to simply not allow a
rw mount on top of ro mount. However, a ro eCryptfs mount on top of a rw
mount is valid and still allowed.

https://launchpad.net/bugs/1009207

Signed-off-by: Tyler Hicks 
Reported-by: Stefan Beller 
Cc: John Johansen 
Cc: Herton Ronaldo Krzesinski 
Signed-off-by: Greg Kroah-Hartman

eCryptfs: Write out all dirty pages just before releasing the lower file

2012-10-21T16:28:01+00:00

commit 7149f2558d5b5b988726662fe58b1c388337805b upstream.

Fixes a regression caused by:

821f749 eCryptfs: Revert to a writethrough cache model

That patch reverted some code (specifically, 32001d6f) that was
necessary to properly handle open() -> mmap() -> close() -> dirty pages
-> munmap(), because the lower file could be closed before the dirty
pages are written out.

Rather than reapplying 32001d6f, this approach is a better way of
ensuring that the lower file is still open in order to handle writing
out the dirty pages. It is called from ecryptfs_release(), while we have
a lock on the lower file pointer, just before the lower file gets the
final fput() and we overwrite the pointer.

https://launchpad.net/bugs/1047261

Signed-off-by: Tyler Hicks 
Reported-by: Artemy Tregubenko 
Tested-by: Artemy Tregubenko 
Tested-by: Colin Ian King 
Signed-off-by: Greg Kroah-Hartman

ecryptfs: make register_filesystem() the last potential failure exit

2012-03-21T01:29:49+00:00

Signed-off-by: Al Viro

switch open-coded instances of d_make_root() to new helper

2012-03-21T01:29:35+00:00

Signed-off-by: Al Viro

Ecryptfs: Add mount option to check uid of device being mounted = expect uid

2011-08-10T04:29:01+00:00

Close a TOCTOU race for mounts done via ecryptfs-mount-private.  The mount
source (device) can be raced when the ownership test is done in userspace.
Provide Ecryptfs a means to force the uid check at mount time.

Signed-off-by: John Johansen 
Cc: 
Signed-off-by: Tyler Hicks

eCryptfs: Remove ecryptfs_header_cache_2

2011-05-29T19:24:25+00:00

Now that ecryptfs_lookup_interpose() is no longer using
ecryptfs_header_cache_2 to read in metadata, the kmem_cache can be
removed and the ecryptfs_header_cache_1 kmem_cache can be renamed to
ecryptfs_header_cache.

Signed-off-by: Tyler Hicks

eCryptfs: Fix new inode race condition

2011-05-29T19:23:39+00:00

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 
Reported-by: David 
Tested-by: David

eCryptfs: Consolidate inode functions into inode.c

2011-05-29T17:49:53+00:00

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 
Tested-by: David