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2010-04-19eCryptfs: Copy lower directory inode times and size on linkTyler Hicks1-2/+2
The timestamps and size of a lower inode involved in a link() call was being copied to the upper parent inode. Instead, we should be copying lower parent inode's timestamps and size to the upper parent inode. I discovered this bug using the POSIX test suite at Tuxera. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-04-19ecryptfs: fix use with tmpfs by removing d_drop from ecryptfs_destroy_inodeJeff Mahoney1-1/+0
Since tmpfs has no persistent storage, it pins all its dentries in memory so they have d_count=1 when other file systems would have d_count=0. ->lookup is only used to create new dentries. If the caller doesn't instantiate it, it's freed immediately at dput(). ->readdir reads directly from the dcache and depends on the dentries being hashed. When an ecryptfs mount is mounted, it associates the lower file and dentry with the ecryptfs files as they're accessed. When it's umounted and destroys all the in-memory ecryptfs inodes, it fput's the lower_files and d_drop's the lower_dentries. Commit 4981e081 added this and a d_delete in 2008 and several months later commit caeeeecf removed the d_delete. I believe the d_drop() needs to be removed as well. The d_drop effectively hides any file that has been accessed via ecryptfs from the underlying tmpfs since it depends on it being hashed for it to be accessible. I've removed the d_drop on my development node and see no ill effects with basic testing on both tmpfs and persistent storage. As a side effect, after ecryptfs d_drops the dentries on tmpfs, tmpfs BUGs on umount. This is due to the dentries being unhashed. tmpfs->kill_sb is kill_litter_super which calls d_genocide to drop the reference pinning the dentry. It skips unhashed and negative dentries, but shrink_dcache_for_umount_subtree doesn't. Since those dentries still have an elevated d_count, we get a BUG(). This patch removes the d_drop call and fixes both issues. This issue was reported at: https://bugzilla.novell.com/show_bug.cgi?id=567887 Reported-by: Árpád Bíró <biroa@demasz.hu> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Cc: Dustin Kirkland <kirkland@canonical.com> Cc: stable@kernel.org Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-04-19ecryptfs: fix error code for missing xattrs in lower fsChristian Pulvermacher1-4/+4
If the lower file system driver has extended attributes disabled, ecryptfs' own access functions return -ENOSYS instead of -EOPNOTSUPP. This breaks execution of programs in the ecryptfs mount, since the kernel expects the latter error when checking for security capabilities in xattrs. Signed-off-by: Christian Pulvermacher <pulvermacher@gmx.de> Cc: stable@kernel.org Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-04-19eCryptfs: Decrypt symlink target for stat sizeTyler Hicks1-48/+52
Create a getattr handler for eCryptfs symlinks that is capable of reading the lower target and decrypting its path. Prior to this patch, a stat's st_size field would represent the strlen of the encrypted path, while readlink() would return the strlen of the decrypted path. This could lead to confusion in some userspace applications, since the two values should be equal. https://bugs.launchpad.net/bugs/524919 Reported-by: Loïc Minier <loic.minier@canonical.com> Cc: stable@kernel.org Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo11-0/+11
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>
2010-03-23eCryptfs: Strip metadata in xattr flag in encrypted viewTyler Hicks3-4/+22
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>
2010-03-23eCryptfs: Clear buffer before reading in metadata xattrTyler Hicks2-0/+2
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>
2010-03-23eCryptfs: Rename ecryptfs_crypt_stat.num_header_bytes_at_frontTyler Hicks4-20/+15
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>
2010-03-23eCryptfs: Fix metadata in xattr feature regressionTyler Hicks4-18/+18
Fixes regression in 8faece5f906725c10e7a1f6caf84452abadbdc7b 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>
2010-01-19ecryptfs: use after freeDan Carpenter1-2/+2
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>
2010-01-19ecryptfs: Eliminate useless codeJulia Lawall1-1/+1
The variable lower_dentry is initialized twice to the same (side effect-free) expression. Drop one initialization. A simplified version of the semantic match that finds this problem is: (http://coccinelle.lip6.fr/) // <smpl> @forall@ idexpression *x; identifier f!=ERR_PTR; @@ x = f(...) ... when != x ( x = f(...,<+...x...+>,...) | * x = f(...) ) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19ecryptfs: fix interpose/interpolate typos in commentsErez Zadok1-2/+2
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Acked-by: Dustin Kirkland <kirkland@canonical.com> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19ecryptfs: pass matching flags to interpose as defined and used thereErez Zadok1-1/+2
ecryptfs_interpose checks if one of the flags passed is ECRYPTFS_INTERPOSE_FLAG_D_ADD, defined as 0x00000001 in ecryptfs_kernel.h. But the only user of ecryptfs_interpose to pass a non-zero flag to it, has hard-coded the value as "1". This could spell trouble if any of these values changes in the future. Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Cc: Dustin Kirkland <kirkland@canonical.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19ecryptfs: remove unnecessary d_drop calls in ecryptfs_linkErez Zadok1-3/+0
Unnecessary because it would unhash perfectly valid dentries, causing them to have to be re-looked up the next time they're needed, which presumably is right after. Signed-off-by: Aseem Rastogi <arastogi@cs.sunysb.edu> Signed-off-by: Shrikar archak <shrikar84@gmail.com> Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Cc: Saumitra Bhanage <sbhanage@cs.sunysb.edu> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19ecryptfs: don't ignore return value from lock_renameErez Zadok1-1/+12
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Cc: Dustin Kirkland <kirkland@canonical.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19ecryptfs: initialize private persistent file before dereferencing pointerErez Zadok1-7/+7
Ecryptfs_open dereferences a pointer to the private lower file (the one stored in the ecryptfs inode), without checking if the pointer is NULL. Right afterward, it initializes that pointer if it is NULL. Swap order of statements to first initialize. Bug discovered by Duckjin Kang. Signed-off-by: Duckjin Kang <fromdj2k@gmail.com> Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Cc: Dustin Kirkland <kirkland@canonical.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@kernel.org> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19eCryptfs: Remove mmap from directory operationsTyler Hicks1-1/+0
Adrian reported that mkfontscale didn't work inside of eCryptfs mounts. Strace revealed the following: open("./", O_RDONLY|O_NONBLOCK|O_LARGEFILE|O_DIRECTORY|O_CLOEXEC) = 3 fcntl64(3, F_GETFD) = 0x1 (flags FD_CLOEXEC) open("./fonts.scale", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 4 getdents(3, /* 80 entries */, 32768) = 2304 open("./.", O_RDONLY) = 5 fcntl64(5, F_SETFD, FD_CLOEXEC) = 0 fstat64(5, {st_mode=S_IFDIR|0755, st_size=16384, ...}) = 0 mmap2(NULL, 16384, PROT_READ, MAP_PRIVATE, 5, 0) = 0xb7fcf000 close(5) = 0 --- SIGBUS (Bus error) @ 0 (0) --- +++ killed by SIGBUS +++ The mmap2() on a directory was successful, resulting in a SIGBUS signal later. This patch removes mmap() from the list of possible ecryptfs_dir_fops so that mmap() isn't possible on eCryptfs directory files. https://bugs.launchpad.net/ecryptfs/+bug/400443 Reported-by: Adrian C. <anrxc@sysphere.org> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19eCryptfs: Add getattr functionTyler Hicks1-0/+16
The i_blocks field of an eCryptfs inode cannot be trusted, but generic_fillattr() uses it to instantiate the blocks field of a stat() syscall when a filesystem doesn't implement its own getattr(). Users have noticed that the output of du is incorrect on newly created files. This patch creates ecryptfs_getattr() which calls into the lower filesystem's getattr() so that eCryptfs can use its kstat.blocks value after calling generic_fillattr(). It is important to note that the block count includes the eCryptfs metadata stored in the beginning of the lower file plus any padding used to fill an extent before encryption. https://bugs.launchpad.net/ecryptfs/+bug/390833 Reported-by: Dominic Sacré <dominic.sacre@gmx.de> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-19eCryptfs: Use notify_change for truncating lower inodesTyler Hicks1-32/+67
When truncating inodes in the lower filesystem, eCryptfs directly invoked vmtruncate(). As Christoph Hellwig pointed out, vmtruncate() is a filesystem helper function, but filesystems may need to do more than just a call to vmtruncate(). This patch moves the lower inode truncation out of ecryptfs_truncate() and renames the function to truncate_upper(). truncate_upper() updates an iattr for the lower inode to indicate if the lower inode needs to be truncated upon return. ecryptfs_setattr() then calls notify_change(), using the updated iattr for the lower inode, to complete the truncation. For eCryptfs functions needing to truncate, ecryptfs_truncate() is reintroduced as a simple way to truncate the upper inode to a specified size and then truncate the lower inode accordingly. https://bugs.launchpad.net/bugs/451368 Reported-by: Christoph Hellwig <hch@lst.de> Acked-by: Dustin Kirkland <kirkland@canonical.com> Cc: ecryptfs-devel@lists.launchpad.net Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2010-01-14ecryptfs: Fix refcnt leak on ecryptfs_follow_link() error pathOGAWA Hirofumi1-12/+12
If ->follow_link handler return the error, it should decrement nd->path refcnt. But, ecryptfs_follow_link() doesn't decrement. This patch fix it by using usual nd_set_link() style error handling, instead of playing with nd->path. Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-17fsstack/ecryptfs: remove unused get_nlinks param to fsstack_copy_attr_allErez Zadok3-5/+5
This get_nlinks parameter was never used by the only mainline user, ecryptfs; and it has never been used by unionfs or wrapfs either. Acked-by: Dustin Kirkland <kirkland@canonical.com> Acked-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16Untangling ima mess, part 2: deal with countersAl Viro1-6/+1
* do ima_get_count() in __dentry_open() * stop doing that in followups * move ima_path_check() to right after nameidata_to_filp() * don't bump counters on it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-10-08ima: ecryptfs fix imbalance messageMimi Zohar1-1/+6
The unencrypted files are being measured. Update the counters to get rid of the ecryptfs imbalance message. (http://bugzilla.redhat.com/519737) Reported-by: Sachin Garg Cc: Eric Paris <eparis@redhat.com> Cc: Dustin Kirkland <kirkland@canonical.com> Cc: James Morris <jmorris@namei.org> Cc: David Safford <safford@watson.ibm.com> Cc: stable@kernel.org Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-10-08eCryptfs: Remove Kconfig NET dependency and select MD5Tyler Hicks1-1/+2
eCryptfs no longer uses a netlink interface to communicate with ecryptfsd, so NET is not a valid dependency anymore. MD5 is required and must be built for eCryptfs to be of any use. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-10-08ecryptfs: depends on CRYPTORandy Dunlap1-1/+1
ecryptfs uses crypto APIs so it should depend on CRYPTO. Otherwise many build errors occur. [63 lines not pasted] Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: ecryptfs-devel@lists.launchpad.net Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23eCryptfs: Prevent lower dentry from going negative during unlinkTyler Hicks1-0/+2
When calling vfs_unlink() on the lower dentry, d_delete() turns the dentry into a negative dentry when the d_count is 1. This eventually caused a NULL pointer deref when a read() or write() was done and the negative dentry's d_inode was dereferenced in ecryptfs_read_update_atime() or ecryptfs_getxattr(). Placing mutt's tmpdir in an eCryptfs mount is what initially triggered the oops and I was able to reproduce it with the following sequence: open("/tmp/upper/foo", O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW, 0600) = 3 link("/tmp/upper/foo", "/tmp/upper/bar") = 0 unlink("/tmp/upper/foo") = 0 open("/tmp/upper/bar", O_RDWR|O_CREAT|O_NOFOLLOW, 0600) = 4 unlink("/tmp/upper/bar") = 0 write(4, "eCryptfs test\n"..., 14 <unfinished ...> +++ killed by SIGKILL +++ https://bugs.launchpad.net/ecryptfs/+bug/387073 Reported-by: Loïc Minier <loic.minier@canonical.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Cc: ecryptfs-devel@lists.launchpad.net Cc: stable <stable@kernel.org> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23eCryptfs: Propagate vfs_read and vfs_write return codesTyler Hicks3-29/+26
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>
2009-09-23eCryptfs: Validate global auth tok keysTyler Hicks1-1/+3
When searching through the global authentication tokens for a given key signature, verify that a matching key has not been revoked and has not expired. This allows the `keyctl revoke` command to be properly used on keys in use by eCryptfs. 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>
2009-09-23eCryptfs: Filename encryption only supports password auth tokensTyler Hicks2-4/+14
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>
2009-09-23eCryptfs: Check for O_RDONLY lower inodes when opening lower filesTyler Hicks2-18/+9
If the lower inode is read-only, don't attempt to open the lower file read/write and don't hand off the open request to the privileged eCryptfs kthread for opening it read/write. Instead, only try an unprivileged, read-only open of the file and give up if that fails. This patch fixes an oops when eCryptfs is mounted on top of a read-only mount. Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Eric Sandeen <esandeen@redhat.com> Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Cc: ecryptfs-devel@lists.launchpad.net Cc: stable <stable@kernel.org> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-09-23eCryptfs: Handle unrecognized tag 3 cipher codesTyler Hicks2-3/+8
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>
2009-09-23ecryptfs: improved dependency checking and reportingDave Hansen2-3/+6
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>
2009-09-23eCryptfs: Fix lockdep-reported AB-BA mutex issueRoland Dreier2-10/+9
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>
2009-09-23ecryptfs: Remove unneeded locking that triggers lockdep false positivesRoland Dreier2-4/+0
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>
2009-09-22const: mark remaining address_space_operations constAlexey Dobriyan2-2/+2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-28eCryptfs: parse_tag_3_packet check tag 3 packet encrypted key sizeRamon de Carvalho Valle1-0/+7
The parse_tag_3_packet function does not check if the tag 3 packet contains a encrypted key size larger than ECRYPTFS_MAX_ENCRYPTED_KEY_BYTES. Signed-off-by: Ramon de Carvalho Valle <ramon@risesecurity.org> [tyhicks@linux.vnet.ibm.com: Added printk newline and changed goto to out_free] Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Cc: stable@kernel.org (2.6.27 and 30) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-28eCryptfs: Check Tag 11 literal data buffer sizeTyler Hicks1-0/+6
Tag 11 packets are stored in the metadata section of an eCryptfs file to store the key signature(s) used to encrypt the file encryption key. After extracting the packet length field to determine the key signature length, a check is not performed to see if the length would exceed the key signature buffer size that was passed into parse_tag_11_packet(). Thanks to Ramon de Carvalho Valle for finding this bug using fsfuzzer. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Cc: stable@kernel.org (2.6.27 and 30) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11push BKL down into ->put_superChristoph Hellwig1-0/+5
Move BKL into ->put_super from the only caller. A couple of filesystems had trivial enough ->put_super (only kfree and NULLing of s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs, hugetlbfs, omfs, qnx4, shmem, all others got the full treatment. Most of them probably don't need it, but I'd rather sort that out individually. Preferably after all the other BKL pushdowns in that area. [AV: original used to move lock_super() down as well; these changes are removed since we don't do lock_super() at all in generic_shutdown_super() now] [AV: fuse, btrfs and xfs are known to need no damn BKL, exempt] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09Convert obvious places to deactivate_locked_super()Al Viro1-3/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-27eCryptfs: Fix min function comparison warningTyler Hicks1-1/+1
This warning shows up on 64 bit builds: fs/ecryptfs/inode.c:693: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-27ecryptfs: fix printk format warningRandy Dunlap1-1/+1
fs/ecryptfs/inode.c:670: warning: format '%d' expects type 'int', but argument 3 has type 'size_t' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Cc: Dustin Kirkland <kirkland@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2009-04-22eCryptfs: Larger buffer for encrypted symlink targetsTyler Hicks1-6/+18
When using filename encryption with eCryptfs, the value of the symlink in the lower filesystem is encrypted and stored as a Tag 70 packet. This results in a longer symlink target than if the target value wasn't encrypted. Users were reporting these messages in their syslog: [ 45.653441] ecryptfs_parse_tag_70_packet: max_packet_size is [56]; real packet size is [51] [ 45.653444] ecryptfs_decode_and_decrypt_filename: Could not parse tag 70 packet from filename; copying through filename as-is This was due to bufsiz, one the arguments in readlink(), being used to when allocating the buffer passed to the lower inode's readlink(). That symlink target may be very large, but when decoded and decrypted, could end up being smaller than bufsize. To fix this, the buffer passed to the lower inode's readlink() will always be PATH_MAX in size when filename encryption is enabled. Any necessary truncation occurs after the decoding and decrypting. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22eCryptfs: Lock lower directory inode mutex during lookupTyler Hicks1-0/+4
This patch locks the lower directory inode's i_mutex before calling lookup_one_len() to find the appropriate dentry in the lower filesystem. This bug was found thanks to the warning set in commit 2f9092e1. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22eCryptfs: Remove ecryptfs_unlink_sigs warningsTyler Hicks3-1/+8
A feature was added to the eCryptfs umount helper to automatically unlink the keys used for an eCryptfs mount from the kernel keyring upon umount. This patch keeps the unrecognized mount option warnings for ecryptfs_unlink_sigs out of the logs. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22eCryptfs: Fix data corruption when using ecryptfs_passthroughTyler Hicks4-32/+41
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>
2009-04-22eCryptfs: Print FNEK sig properly in /proc/mountsTyler Hicks1-1/+4
The filename encryption key signature is not properly displayed in /proc/mounts. The "ecryptfs_sig=" mount option name is displayed for all global authentication tokens, included those for filename keys. This patch checks the global authentication token flags to determine if the key is a FEKEK or FNEK and prints the appropriate mount option name before the signature. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22eCryptfs: NULL pointer dereference in ecryptfs_send_miscdev()Tyler Hicks2-99/+11
If data is NULL, msg_ctx->msg is set to NULL and then dereferenced afterwards. ecryptfs_send_raw_message() is the only place that ecryptfs_send_miscdev() is called with data being NULL, but the only caller of that function (ecryptfs_process_helo()) is never called. In short, there is currently no way to trigger the NULL pointer dereference. This patch removes the two unused functions and modifies ecryptfs_send_miscdev() to remove the NULL dereferences. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-22eCryptfs: Copy lower inode attrs before dentry instantiationTyler Hicks1-4/+4
Copies the lower inode attributes to the upper inode before passing the upper inode to d_instantiate(). This is important for security_d_instantiate(). The problem was discovered by a user seeing SELinux denials like so: type=AVC msg=audit(1236812817.898:47): avc: denied { 0x100000 } for pid=3584 comm="httpd" name="testdir" dev=ecryptfs ino=943872 scontext=root:system_r:httpd_t:s0 tcontext=root:object_r:httpd_sys_content_t:s0 tclass=file Notice target class is file while testdir is really a directory, confusing the permission translation (0x100000) due to the wrong i_mode. Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
2009-04-20ecryptfs: use memdup_user()Li Zefan1-10/+5
Remove open-coded memdup_user(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-01ecryptfs: use kzfree()Johannes Weiner2-4/+2
Use kzfree() instead of memset() + kfree(). Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Acked-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>