Commit Graph

726 Commits

Author SHA1 Message Date
David Oberhollenzer
59a74990f8 ubifs: Fix data node size for truncating uncompressed nodes
Currently, the function truncate_data_node only updates the
destination data node size if compression is used. For
uncompressed nodes, the old length is incorrectly retained.

This patch makes sure that the length is correctly set when
compression is disabled.

Fixes: 7799953b34 ("ubifs: Implement encrypt/decrypt for all IO")
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:49:06 +02:00
David Gstir
f34e87f58d ubifs: Don't encrypt special files on creation
When a new inode is created, we check if the containing folder has a encryption
policy set and inherit that. This should however only be done for regular
files, links and subdirectories. Not for sockes fifos etc.

Fixes: d475a50745 ("ubifs: Add skeleton for fscrypto")
Cc: stable@vger.kernel.org
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:49:05 +02:00
Hyunchul Lee
bb50c63244 ubifs: Fix memory leak in RENAME_WHITEOUT error path in do_rename
in RENAME_WHITEOUT error path, fscrypt_name should be freed.

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:49:05 +02:00
Hyunchul Lee
4d35ca4f77 ubifs: Fix inode data budget in ubifs_mknod
Assign inode data budget to budget request correctly.

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:49:05 +02:00
Richard Weinberger
272eda8298 ubifs: Correctly evict xattr inodes
UBIFS handles extended attributes just like files, as consequence of
that, they also have inodes.
Therefore UBIFS does all the inode machinery also for xattrs. Since new
inodes have i_nlink of 1, a file or xattr inode will be evicted
if i_nlink goes down to 0 after an unlink. UBIFS assumes this model also
for xattrs, which is not correct.
One can create a file "foo" with xattr "user.test". By reading
"user.test" an inode will be created, and by deleting "user.test" it
will get evicted later. The assumption breaks if the file "foo", which
hosts the xattrs, will be removed. VFS nor UBIFS does not remove each
xattr via ubifs_xattr_remove(), it just removes the host inode from
the TNC and all underlying xattr nodes too and the inode will remain
in the cache and wastes memory.

To solve this problem, remove xattr inodes from the VFS inode cache in
ubifs_xattr_remove() to make sure that they get evicted.

Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Cc: <stable@vger.kernel.org>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:49:04 +02:00
Richard Weinberger
e996bfd428 ubifs: Unexport ubifs_inode_slab
This SLAB is only being used in super.c, there is no need to expose
it into the global namespace.

Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-14 22:48:43 +02:00
Eric Biggers
af65936a7a ubifs: don't bother checking for encryption key in ->mmap()
Since only an open file can be mmap'ed, and we only allow open()ing an
encrypted file when its key is available, there is no need to check for
the key again before permitting each mmap().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-05 23:52:50 +02:00
Eric Biggers
4afb9996a2 ubifs: require key for truncate(2) of encrypted file
Currently, filesystems allow truncate(2) on an encrypted file without
the encryption key.  However, it's impossible to correctly handle the
case where the size being truncated to is not a multiple of the
filesystem block size, because that would require decrypting the final
block, zeroing the part beyond i_size, then encrypting the block.

As other modifications to encrypted file contents are prohibited without
the key, just prohibit truncate(2) as well, making it fail with ENOKEY.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-07-05 23:52:50 +02:00
Linus Torvalds
b53c4d5eb7 This pull request contains updates for both UBI and UBIFS:
- New config option CONFIG_UBIFS_FS_SECURITY
 - Minor improvements
 - Random fixes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABAgAGBQJZFuwKAAoJEEtJtSqsAOnWYrUP/0/y7PEh0ZGdi4kkQy/CnuJr
 pmybsQ0TbLoljahuDXqShKkMNvuXIvKSKcHROIsXreG+DCfC3v/srZlvRt7UCPOE
 QVvjh0sQTaMUrfcaTTM9g3Im/BZX9MueTaSF2Rgx1lF+R2t3InW1bv9hvmQxfoEA
 N75tJgH69mii5pDWuGgLLjmmxhbSkMGpM31QeO5DUaLRqdXcc5L5iK5Hnd+Wtj81
 oSB5RsergCfk17jaWH2e7G03LB2tm6AhM5oksTOpZ9+OIW9GOiUMfjYFC2ZYRwzx
 zHhnh0rGPfFv0jO5u4CXtWaQDfxyw6Z7XLK+Xo1RemkhM/7AQl2xetfIVDXErgoA
 NxxN/a8MWcEpJ2x6y/Z8740HXjyQjt9h3nHzlVPNP8hz68J796E7UzRjCQtf7Iyh
 xqhfjMabxfBqcLkTESvgmjcuwo1IkqOaFBjIw2Cd2nfBEkCKzoaINjRHitgUGj/z
 Mm1CJNWvaK6QTdZ3iCETCyPQI02A+4ZXhDf/QZS3wRAMc1v45pS/dVeBn+0F8Nrc
 ASiQwcd7u1IfJa3A6d6DgMECUWBXjc1GGMfMyhS/ta56pOfe1RyR3bg9WuISqUMe
 86id9tiSs7cP2UVFTrFFFWAO3rATj+9cOO9f2LTujPzcd88cJhKSykaLPmELfyE9
 YUPw9lpExwyXLn7S46LQ
 =9ZJe
 -----END PGP SIGNATURE-----

Merge tag 'upstream-4.12-rc1' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS updates from Richard Weinberger:

 - new config option CONFIG_UBIFS_FS_SECURITY

 - minor improvements

 - random fixes

* tag 'upstream-4.12-rc1' of git://git.infradead.org/linux-ubifs:
  ubi: Add debugfs file for tracking PEB state
  ubifs: Fix a typo in comment of ioctl2ubifs & ubifs2ioctl
  ubifs: Remove unnecessary assignment
  ubifs: Fix cut and paste error on sb type comparisons
  ubi: fastmap: Fix slab corruption
  ubifs: Add CONFIG_UBIFS_FS_SECURITY to disable/enable security labels
  ubi: Make mtd parameter readable
  ubi: Fix section mismatch
2017-05-13 10:23:12 -07:00
Linus Torvalds
bf5f89463f Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - the rest of MM

 - various misc things

 - procfs updates

 - lib/ updates

 - checkpatch updates

 - kdump/kexec updates

 - add kvmalloc helpers, use them

 - time helper updates for Y2038 issues. We're almost ready to remove
   current_fs_time() but that awaits a btrfs merge.

 - add tracepoints to DAX

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits)
  drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4
  selftests/vm: add a test for virtual address range mapping
  dax: add tracepoint to dax_insert_mapping()
  dax: add tracepoint to dax_writeback_one()
  dax: add tracepoints to dax_writeback_mapping_range()
  dax: add tracepoints to dax_load_hole()
  dax: add tracepoints to dax_pfn_mkwrite()
  dax: add tracepoints to dax_iomap_pte_fault()
  mtd: nand: nandsim: convert to memalloc_noreclaim_*()
  treewide: convert PF_MEMALLOC manipulations to new helpers
  mm: introduce memalloc_noreclaim_{save,restore}
  mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC
  mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required
  mm/huge_memory.c: use zap_deposited_table() more
  time: delete CURRENT_TIME_SEC and CURRENT_TIME
  gfs2: replace CURRENT_TIME with current_time
  apparmorfs: replace CURRENT_TIME with current_time()
  lustre: replace CURRENT_TIME macro
  fs: ubifs: replace CURRENT_TIME_SEC with current_time
  fs: ufs: use ktime_get_real_ts64() for birthtime
  ...
2017-05-08 18:17:56 -07:00
Deepa Dinamani
607a11ad94 fs: ubifs: replace CURRENT_TIME_SEC with current_time
CURRENT_TIME_SEC is not y2038 safe.  current_time() will be transitioned
to use 64 bit time along with vfs in a separate patch.  There is no plan
to transition CURRENT_TIME_SEC to use y2038 safe time interfaces.

current_time() returns timestamps according to the granularities set in
the inode's super_block.  The granularity check to call
current_fs_time() or CURRENT_TIME_SEC is not required.

Use current_time() directly to update inode timestamp.  Use
timespec_trunc during file system creation, before the first inode is
created.

Link: http://lkml.kernel.org/r/1491613030-11599-9-git-send-email-deepa.kernel@gmail.com
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:15 -07:00
Rock Lee
798868c021 ubifs: Fix a typo in comment of ioctl2ubifs & ubifs2ioctl
Change 'convert' to 'converts'
Change 'UBIFS' to 'UBIFS inode flags'

Signed-off-by: Rock Lee <rockdotlee@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-05-08 20:48:55 +02:00
Stefan Agner
2a068daf57 ubifs: Remove unnecessary assignment
Assigning a value of a variable to itself is not useful.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-05-08 20:48:47 +02:00
Colin Ian King
6a258f7d0f ubifs: Fix cut and paste error on sb type comparisons
The check for the bad node type of sb->type is checking sa->type
and not sb-type. This looks like a cut and paste error. Fix this.

Detected by PVS-Studio, warning: V581

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-05-08 20:48:41 +02:00
Hyunchul Lee
8326c1eec2 ubifs: Add CONFIG_UBIFS_FS_SECURITY to disable/enable security labels
When write syscall is called, every time security label is searched to
determine that file's privileges should be changed.
If LSM(Linux Security Model) is not used, this is useless.

So introduce CONFIG_UBIFS_SECURITY to disable security labels. it's default
value is "y".

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-05-08 20:48:23 +02:00
Linus Torvalds
677375cef8 Only bug fixes and cleanups for this merge window.
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlkPYHkACgkQ8vlZVpUN
 gaM97ggAlOm8n/tlbcdonX/+HHjlnqcy5uYD7A9AH/JordpRzy4eqcMbxMG39p1R
 DBtjo9Y0i3iFEGajRc0h7KXDLeTBUQ/JZpR8H60MFfAQHnTowuI91eb3/6QeZiHh
 CN/2KKzpYitPIEUfEHnVeYKOfvrzR7je5hrEiAwEkPeKv7XyrNVM0LHQ/jKpbQwg
 ntIzHvxjQyo8plx/m5S4Yew7tqjYpNiq4plmyk/Vxtw2FmB/FC76UxYeadoB3EI5
 etw+bCORB0tFZO27o56kXywg+mDcp7HEtVvq9LG28oEuBDAVKNoeKEvV7SiOBlZp
 +HnqIz5Hx1UTxOlTAc10IjvEhriEuw==
 =qCDl
 -----END PGP SIGNATURE-----

Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Only bug fixes and cleanups for this merge window"

* tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: correct collision claim for digested names
  MAINTAINERS: fscrypt: update mailing list, patchwork, and git
  ext4: clean up ext4_match() and callers
  f2fs: switch to using fscrypt_match_name()
  ext4: switch to using fscrypt_match_name()
  fscrypt: introduce helper function for filename matching
  fscrypt: avoid collisions when presenting long encrypted filenames
  f2fs: check entire encrypted bigname when finding a dentry
  ubifs: check for consistent encryption contexts in ubifs_lookup()
  f2fs: sync f2fs_lookup() with ext4_lookup()
  ext4: remove "nokey" check from ext4_lookup()
  fscrypt: fix context consistency check when key(s) unavailable
  fscrypt: Remove __packed from fscrypt_policy
  fscrypt: Move key structure and constants to uapi
  fscrypt: remove fscrypt_symlink_data_len()
  fscrypt: remove unnecessary checks for NULL operations
2017-05-08 11:40:34 -07:00
Eric Biggers
413d5a9edb ubifs: check for consistent encryption contexts in ubifs_lookup()
As ext4 and f2fs do, ubifs should check for consistent encryption
contexts during ->lookup() in an encrypted directory.  This protects
certain users of filesystem encryption against certain types of offline
attacks.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-05-04 11:44:35 -04:00
Linus Torvalds
694752922b Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..
2017-05-01 10:39:57 -07:00
Jan Kara
99edd4580b ubifs: Convert to separately allocated bdi
Allocate struct backing_dev_info separately instead of embedding it
inside the superblock. This unifies handling of bdi among users.

CC: Richard Weinberger <richard@nod.at>
CC: Artem Bityutskiy <dedekind1@gmail.com>
CC: Adrian Hunter <adrian.hunter@intel.com>
CC: linux-mtd@lists.infradead.org
Acked-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:09:55 -06:00
Richard Weinberger
32fe905c17 ubifs: Fix O_TMPFILE corner case in ubifs_link()
It is perfectly fine to link a tmpfile back using linkat().
Since tmpfiles are created with a link count of 0 they appear
on the orphan list, upon re-linking the inode has to be removed
from the orphan list again.

Ralph faced a filesystem corruption in combination with overlayfs
due to this bug.

Cc: <stable@vger.kernel.org>
Cc: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Reported-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Tested-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Reported-by: Amir Goldstein <amir73il@gmail.com>
Fixes: 474b93704f ("ubifs: Implement O_TMPFILE")
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-04-18 23:18:02 +02:00
Felix Fietkau
c3d9fda688 ubifs: Fix RENAME_WHITEOUT support
Remove faulty leftover check in do_rename(), apparently introduced in a
merge that combined whiteout support changes with commit f03b8ad8d3
("fs: support RENAME_NOREPLACE for local filesystems")

Fixes: f03b8ad8d3 ("fs: support RENAME_NOREPLACE for local
filesystems")
Fixes: 9e0a1fff8d ("ubifs: Implement RENAME_WHITEOUT")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-30 09:28:02 +02:00
Hyunchul Lee
33fda9fa9f ubifs: Fix debug messages for an invalid filename in ubifs_dump_inode
instead of filenames, print inode numbers, file types, and length.

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-30 09:27:53 +02:00
Hyunchul Lee
e328379a18 ubifs: Fix debug messages for an invalid filename in ubifs_dump_node
if a character is not printable, print '?' instead of that.

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-30 09:27:47 +02:00
Hyunchul Lee
b20e2d9999 ubifs: Remove filename from debug messages in ubifs_readdir
if filename is encrypted, filename could have no printable characters.
so remove it.

Signed-off-by: Hyunchul Lee <cheol.lee@lge.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-30 09:27:28 +02:00
Richard Weinberger
63ed657362 ubifs: Fix memory leak in error path in ubifs_mknod
When fscrypt_setup_filename() fails we have to free dev.

Signed-off-by: Richard Weinberger <richard@nod.at>
2017-03-30 09:27:27 +02:00
David Howells
a528d35e8b statx: Add a system call to make enhanced file info available
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.

The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode.  This change is propagated to the vfs_getattr*()
function.

Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.

========
OVERVIEW
========

The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.

A number of requests were gathered for features to be included.  The
following have been included:

 (1) Make the fields a consistent size on all arches and make them large.

 (2) Spare space, request flags and information flags are provided for
     future expansion.

 (3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
     __s64).

 (4) Creation time: The SMB protocol carries the creation time, which could
     be exported by Samba, which will in turn help CIFS make use of
     FS-Cache as that can be used for coherency data (stx_btime).

     This is also specified in NFSv4 as a recommended attribute and could
     be exported by NFSD [Steve French].

 (5) Lightweight stat: Ask for just those details of interest, and allow a
     netfs (such as NFS) to approximate anything not of interest, possibly
     without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
     Dilger] (AT_STATX_DONT_SYNC).

 (6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
     its cached attributes are up to date [Trond Myklebust]
     (AT_STATX_FORCE_SYNC).

And the following have been left out for future extension:

 (7) Data version number: Could be used by userspace NFS servers [Aneesh
     Kumar].

     Can also be used to modify fill_post_wcc() in NFSD which retrieves
     i_version directly, but has just called vfs_getattr().  It could get
     it from the kstat struct if it used vfs_xgetattr() instead.

     (There's disagreement on the exact semantics of a single field, since
     not all filesystems do this the same way).

 (8) BSD stat compatibility: Including more fields from the BSD stat such
     as creation time (st_btime) and inode generation number (st_gen)
     [Jeremy Allison, Bernd Schubert].

 (9) Inode generation number: Useful for FUSE and userspace NFS servers
     [Bernd Schubert].

     (This was asked for but later deemed unnecessary with the
     open-by-handle capability available and caused disagreement as to
     whether it's a security hole or not).

(10) Extra coherency data may be useful in making backups [Andreas Dilger].

     (No particular data were offered, but things like last backup
     timestamp, the data version number and the DOS archive bit would come
     into this category).

(11) Allow the filesystem to indicate what it can/cannot provide: A
     filesystem can now say it doesn't support a standard stat feature if
     that isn't available, so if, for instance, inode numbers or UIDs don't
     exist or are fabricated locally...

     (This requires a separate system call - I have an fsinfo() call idea
     for this).

(12) Store a 16-byte volume ID in the superblock that can be returned in
     struct xstat [Steve French].

     (Deferred to fsinfo).

(13) Include granularity fields in the time data to indicate the
     granularity of each of the times (NFSv4 time_delta) [Steve French].

     (Deferred to fsinfo).

(14) FS_IOC_GETFLAGS value.  These could be translated to BSD's st_flags.
     Note that the Linux IOC flags are a mess and filesystems such as Ext4
     define flags that aren't in linux/fs.h, so translation in the kernel
     may be a necessity (or, possibly, we provide the filesystem type too).

     (Some attributes are made available in stx_attributes, but the general
     feeling was that the IOC flags were to ext[234]-specific and shouldn't
     be exposed through statx this way).

(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
     Michael Kerrisk].

     (Deferred, probably to fsinfo.  Finding out if there's an ACL or
     seclabal might require extra filesystem operations).

(16) Femtosecond-resolution timestamps [Dave Chinner].

     (A __reserved field has been left in the statx_timestamp struct for
     this - if there proves to be a need).

(17) A set multiple attributes syscall to go with this.

===============
NEW SYSTEM CALL
===============

The new system call is:

	int ret = statx(int dfd,
			const char *filename,
			unsigned int flags,
			unsigned int mask,
			struct statx *buffer);

The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat().  There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags.  There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.

Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):

 (1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
     respect.

 (2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
     its attributes with the server - which might require data writeback to
     occur to get the timestamps correct.

 (3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
     network filesystem.  The resulting values should be considered
     approximate.

mask is a bitmask indicating the fields in struct statx that are of
interest to the caller.  The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat().  It should be noted that asking for
more information may entail extra I/O operations.

buffer points to the destination for the data.  This must be 256 bytes in
size.

======================
MAIN ATTRIBUTES RECORD
======================

The following structures are defined in which to return the main attribute
set:

	struct statx_timestamp {
		__s64	tv_sec;
		__s32	tv_nsec;
		__s32	__reserved;
	};

	struct statx {
		__u32	stx_mask;
		__u32	stx_blksize;
		__u64	stx_attributes;
		__u32	stx_nlink;
		__u32	stx_uid;
		__u32	stx_gid;
		__u16	stx_mode;
		__u16	__spare0[1];
		__u64	stx_ino;
		__u64	stx_size;
		__u64	stx_blocks;
		__u64	__spare1[1];
		struct statx_timestamp	stx_atime;
		struct statx_timestamp	stx_btime;
		struct statx_timestamp	stx_ctime;
		struct statx_timestamp	stx_mtime;
		__u32	stx_rdev_major;
		__u32	stx_rdev_minor;
		__u32	stx_dev_major;
		__u32	stx_dev_minor;
		__u64	__spare2[14];
	};

The defined bits in request_mask and stx_mask are:

	STATX_TYPE		Want/got stx_mode & S_IFMT
	STATX_MODE		Want/got stx_mode & ~S_IFMT
	STATX_NLINK		Want/got stx_nlink
	STATX_UID		Want/got stx_uid
	STATX_GID		Want/got stx_gid
	STATX_ATIME		Want/got stx_atime{,_ns}
	STATX_MTIME		Want/got stx_mtime{,_ns}
	STATX_CTIME		Want/got stx_ctime{,_ns}
	STATX_INO		Want/got stx_ino
	STATX_SIZE		Want/got stx_size
	STATX_BLOCKS		Want/got stx_blocks
	STATX_BASIC_STATS	[The stuff in the normal stat struct]
	STATX_BTIME		Want/got stx_btime{,_ns}
	STATX_ALL		[All currently available stuff]

stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.

Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution.  Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.

The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does.  The following
attributes map to FS_*_FL flags and are the same numerical value:

	STATX_ATTR_COMPRESSED		File is compressed by the fs
	STATX_ATTR_IMMUTABLE		File is marked immutable
	STATX_ATTR_APPEND		File is append-only
	STATX_ATTR_NODUMP		File is not to be dumped
	STATX_ATTR_ENCRYPTED		File requires key to decrypt in fs

Within the kernel, the supported flags are listed by:

	KSTAT_ATTR_FS_IOC_FLAGS

[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]

New flags include:

	STATX_ATTR_AUTOMOUNT		Object is an automount trigger

These are for the use of GUI tools that might want to mark files specially,
depending on what they are.

Fields in struct statx come in a number of classes:

 (0) stx_dev_*, stx_blksize.

     These are local system information and are always available.

 (1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
     stx_size, stx_blocks.

     These will be returned whether the caller asks for them or not.  The
     corresponding bits in stx_mask will be set to indicate whether they
     actually have valid values.

     If the caller didn't ask for them, then they may be approximated.  For
     example, NFS won't waste any time updating them from the server,
     unless as a byproduct of updating something requested.

     If the values don't actually exist for the underlying object (such as
     UID or GID on a DOS file), then the bit won't be set in the stx_mask,
     even if the caller asked for the value.  In such a case, the returned
     value will be a fabrication.

     Note that there are instances where the type might not be valid, for
     instance Windows reparse points.

 (2) stx_rdev_*.

     This will be set only if stx_mode indicates we're looking at a
     blockdev or a chardev, otherwise will be 0.

 (3) stx_btime.

     Similar to (1), except this will be set to 0 if it doesn't exist.

=======
TESTING
=======

The following test program can be used to test the statx system call:

	samples/statx/test-statx.c

Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.

Here's some example output.  Firstly, an NFS directory that crosses to
another FSID.  Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.

	[root@andromeda ~]# /tmp/test-statx -A /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:26           Inode: 1703937     Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000
	Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)

Secondly, the result of automounting on that directory.

	[root@andromeda ~]# /tmp/test-statx /warthog/data
	statx(/warthog/data) = 0
	results=7ff
	  Size: 4096            Blocks: 8          IO Block: 1048576  directory
	Device: 00:27           Inode: 2           Links: 125
	Access: (3777/drwxrwxrwx)  Uid:     0   Gid:  4041
	Access: 2016-11-24 09:02:12.219699527+0000
	Modify: 2016-11-17 10:44:36.225653653+0000
	Change: 2016-11-17 10:44:36.225653653+0000

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-02 20:51:15 -05:00
Dave Jiang
11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00
Linus Torvalds
6c24337f22 Various cleanups for the file system encryption feature.
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlirP6wACgkQ8vlZVpUN
 gaMwpQgApR67CxzlstxYjZpWPAqC8McJ2FBDX+mCOle5Vkc1WQDklwr0oCfQThTj
 eDSFRhNfIvyPh0DJ589PxBCsWOqN5h6Si7hD5ZinomVNI+IL89OytaU5EV2OpWaW
 iKdJgO9Tm8U7LuY6FOIoVdX57kUXVdkWoj61rC056B1SNhnNiVeofi7lYDM8Ix4q
 IGSQ9W24iQKmCk4hCwgObhJBRK9RnlOH0GLUmpMaS+jnfnj/uePwdxWEFsPuCOob
 8acAJ49lr55kjIw79E0BAyWxhEZ2aiArHk8PaWynT/DyNq3ftcapPlpftoeba8vo
 glBJRX70QxPvt0iHEp0ykfExkhWhFA==
 =Joki
 -----END PGP SIGNATURE-----

Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt

Pull fscrypt updates from Ted Ts'o:
 "Various cleanups for the file system encryption feature"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: constify struct fscrypt_operations
  fscrypt: properly declare on-stack completion
  fscrypt: split supp and notsupp declarations into their own headers
  fscrypt: remove redundant assignment of res
  fscrypt: make fscrypt_operations.key_prefix a string
  fscrypt: remove unused 'mode' member of fscrypt_ctx
  ext4: don't allow encrypted operations without keys
  fscrypt: make test_dummy_encryption require a keyring key
  fscrypt: factor out bio specific functions
  fscrypt: pass up error codes from ->get_context()
  fscrypt: remove user-triggerable warning messages
  fscrypt: use EEXIST when file already uses different policy
  fscrypt: use ENOTDIR when setting encryption policy on nondirectory
  fscrypt: use ENOKEY when file cannot be created w/o key
2017-02-20 18:22:31 -08:00
Eric Biggers
6f69f0ed61 fscrypt: constify struct fscrypt_operations
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Richard Weinberger <richard@nod.at>
2017-02-08 10:59:57 -05:00
Eric Biggers
46f47e4800 fscrypt: split supp and notsupp declarations into their own headers
Previously, each filesystem configured without encryption support would
define all the public fscrypt functions to their notsupp_* stubs.  This
list of #defines had to be updated in every filesystem whenever a change
was made to the public fscrypt functions.  To make things more
maintainable now that we have three filesystems using fscrypt, split the
old header fscrypto.h into several new headers.  fscrypt_supp.h contains
the real declarations and is included by filesystems when configured
with encryption support, whereas fscrypt_notsupp.h contains the inline
stubs and is included by filesystems when configured without encryption
support.  fscrypt_common.h contains common declarations needed by both.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-02-06 23:26:43 -05:00
Richard Weinberger
1cb51a15b5 ubifs: Fix journal replay wrt. xattr nodes
When replaying the journal it can happen that a journal entry points to
a garbage collected node.
This is the case when a power-cut occurred between a garbage collect run
and a commit. In such a case nodes have to be read using the failable
read functions to detect whether the found node matches what we expect.

One corner case was forgotten, when the journal contains an entry to
remove an inode all xattrs have to be removed too. UBIFS models xattr
like directory entries, so the TNC code iterates over
all xattrs of the inode and removes them too. This code re-uses the
functions for walking directories and calls ubifs_tnc_next_ent().
ubifs_tnc_next_ent() expects to be used only after the journal and
aborts when a node does not match the expected result. This behavior can
render an UBIFS volume unmountable after a power-cut when xattrs are
used.

Fix this issue by using failable read functions in ubifs_tnc_next_ent()
too when replaying the journal.
Cc: stable@vger.kernel.org
Fixes: 1e51764a3c ("UBIFS: add new flash file system")
Reported-by: Rock Lee <rockdotlee@gmail.com>
Reviewed-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 14:35:58 +01:00
Eric Biggers
3d4b2fcbc9 ubifs: remove redundant checks for encryption key
In several places, ubifs checked for an encryption key before creating a
file in an encrypted directory.  This was redundant with
fscrypt_setup_filename() or ubifs_new_inode(), and in the case of
ubifs_link() it broke linking to special files.  So remove the extra
checks.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 14:34:21 +01:00
Eric Biggers
a75467d910 ubifs: allow encryption ioctls in compat mode
The ubifs encryption ioctls did not work when called by a 32-bit program
on a 64-bit kernel.  Since 'struct fscrypt_policy' is not affected by
the word size, ubifs just needs to allow these ioctls through, like what
ext4 and f2fs do.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 14:33:41 +01:00
Arnd Bergmann
404e0b6331 ubifs: add CONFIG_BLOCK dependency for encryption
This came up during the v4.10 merge window:

warning: (UBIFS_FS_ENCRYPTION) selects FS_ENCRYPTION which has unmet direct dependencies (BLOCK)
fs/crypto/crypto.c: In function 'fscrypt_zeroout_range':
fs/crypto/crypto.c:355:9: error: implicit declaration of function 'bio_alloc';did you mean 'd_alloc'? [-Werror=implicit-function-declaration]
   bio = bio_alloc(GFP_NOWAIT, 1);

The easiest way out is to limit UBIFS_FS_ENCRYPTION to configurations
that also enable BLOCK.

Fixes: d475a50745 ("ubifs: Add skeleton for fscrypto")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 14:32:47 +01:00
Peter Rosin
507502adf0 ubifs: fix unencrypted journal write
Without this, I get the following on reboot:

UBIFS error (ubi1:0 pid 703): ubifs_load_znode: bad target node (type 1) length (8240)
UBIFS error (ubi1:0 pid 703): ubifs_load_znode: have to be in range of 48-4144
UBIFS error (ubi1:0 pid 703): ubifs_load_znode: bad indexing node at LEB 13:11080, error 5
 magic          0x6101831
 crc            0xb1cb246f
 node_type      9 (indexing node)
 group_type     0 (no node group)
 sqnum          546
 len            128
 child_cnt      5
 level          0
 Branches:
 0: LEB 14:72088 len 161 key (133, inode)
 1: LEB 14:81120 len 160 key (134, inode)
 2: LEB 20:26624 len 8240 key (134, data, 0)
 3: LEB 14:81280 len 160 key (135, inode)
 4: LEB 20:34864 len 8240 key (135, data, 0)
UBIFS warning (ubi1:0 pid 703): ubifs_ro_mode.part.0: switched to read-only mode, error -22
CPU: 0 PID: 703 Comm: mount Not tainted 4.9.0-next-20161213+ #1197
Hardware name: Atmel SAMA5
[<c010d2ac>] (unwind_backtrace) from [<c010b250>] (show_stack+0x10/0x14)
[<c010b250>] (show_stack) from [<c024df94>] (ubifs_jnl_update+0x2e8/0x614)
[<c024df94>] (ubifs_jnl_update) from [<c0254bf8>] (ubifs_mkdir+0x160/0x204)
[<c0254bf8>] (ubifs_mkdir) from [<c01a6030>] (vfs_mkdir+0xb0/0x104)
[<c01a6030>] (vfs_mkdir) from [<c0286070>] (ovl_create_real+0x118/0x248)
[<c0286070>] (ovl_create_real) from [<c0283ed4>] (ovl_fill_super+0x994/0xaf4)
[<c0283ed4>] (ovl_fill_super) from [<c019c394>] (mount_nodev+0x44/0x9c)
[<c019c394>] (mount_nodev) from [<c019c4ac>] (mount_fs+0x14/0xa4)
[<c019c4ac>] (mount_fs) from [<c01b5338>] (vfs_kern_mount+0x4c/0xd4)
[<c01b5338>] (vfs_kern_mount) from [<c01b6b80>] (do_mount+0x154/0xac8)
[<c01b6b80>] (do_mount) from [<c01b782c>] (SyS_mount+0x74/0x9c)
[<c01b782c>] (SyS_mount) from [<c0107f80>] (ret_fast_syscall+0x0/0x3c)
UBIFS error (ubi1:0 pid 703): ubifs_mkdir: cannot create directory, error -22
overlayfs: failed to create directory /mnt/ovl/work/work (errno: 22); mounting read-only

Fixes: 7799953b34 ("ubifs: Implement encrypt/decrypt for all IO")
Signed-off-by: Peter Rosin <peda@axentia.se>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 14:05:23 +01:00
Colin Ian King
e8f19746e4 ubifs: ensure zero err is returned on successful return
err is no longer being set on a successful return path, causing
a garbage value being returned. Fix this by setting err to zero
for the successful return path.

Found with static analysis by CoverityScan, CID 1389473

Fixes: 7799953b34 ("ubifs: Implement encrypt/decrypt for all IO")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-01-17 13:57:32 +01:00
Eric Biggers
a5d431eff2 fscrypt: make fscrypt_operations.key_prefix a string
There was an unnecessary amount of complexity around requesting the
filesystem-specific key prefix.  It was unclear why; perhaps it was
envisioned that different instances of the same filesystem type could
use different key prefixes, or that key prefixes could be binary.
However, neither of those things were implemented or really make sense
at all.  So simplify the code by making key_prefix a const char *.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2017-01-08 01:03:41 -05:00
Linus Torvalds
231753ef78 Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull partial readlink cleanups from Miklos Szeredi.

This is the uncontroversial part of the readlink cleanup patch-set that
simplifies the default readlink handling.

Miklos and Al are still discussing the rest of the series.

* git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  vfs: make generic_readlink() static
  vfs: remove ".readlink = generic_readlink" assignments
  vfs: default to generic_readlink()
  vfs: replace calling i_op->readlink with vfs_readlink()
  proc/self: use generic_readlink
  ecryptfs: use vfs_get_link()
  bad_inode: add missing i_op initializers
2016-12-17 19:16:12 -08:00
Richard Weinberger
ba75d570b6 ubifs: Initialize fstr_real_len
While fstr_real_len is only being used under if (encrypted),
gcc-6 still warns.

Fixes this false positive:
fs/ubifs/dir.c: In function 'ubifs_readdir':
fs/ubifs/dir.c:629:13: warning: 'fstr_real_len' may be used
uninitialized in this function [-Wmaybe-uninitialized]
    fstr.len = fstr_real_len

Initialize fstr_real_len to make gcc happy.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-14 17:39:21 +01:00
Richard Weinberger
ec9160dacd ubifs: Use fscrypt ioctl() helpers
Commit db717d8e26 ("fscrypto: move ioctl processing more fully into
common code") moved ioctl() related functions into fscrypt and offers
us now a set of helper functions.

Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: David Gstir <david@sigma-star.at>
2016-12-13 19:54:52 +01:00
Richard Weinberger
3858866866 ubifs: Use FS_CFLG_OWN_PAGES
Commit bd7b829038 ("fscrypt: Cleanup page locking requirements for
fscrypt_{decrypt,encrypt}_page()") renamed the flag.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-13 16:18:16 +01:00
Richard Weinberger
fc4b891bbe ubifs: Raise write version to 5
Starting with version 5 the following properties change:
 - UBIFS_FLG_DOUBLE_HASH is mandatory
 - UBIFS_FLG_ENCRYPTION is optional but depdens on UBIFS_FLG_DOUBLE_HASH
 - Filesystems with unknown super block flags will be rejected, this
   allows us in future to add new features without raising the UBIFS
   write version.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
e021986ee4 ubifs: Implement UBIFS_FLG_ENCRYPTION
This feature flag indicates that the filesystem contains encrypted
files.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
d63d61c169 ubifs: Implement UBIFS_FLG_DOUBLE_HASH
This feature flag indicates that all directory entry nodes have a 32bit
cookie set and therefore UBIFS is allowed to perform lookups by hash.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
cc41a53652 ubifs: Use a random number for cookies
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
528e3d178f ubifs: Add full hash lookup support
UBIFS stores a 32bit hash of every file, for traditional lookups by name
this scheme is fine since UBIFS can first try to find the file by the
hash of the filename and upon collisions it can walk through all entries
with the same hash and do a string compare.
When filesnames are encrypted fscrypto will ask the filesystem for a
unique cookie, based on this cookie the filesystem has to be able to
locate the target file again. With 32bit hashes this is impossible
because the chance for collisions is very high. Do deal with that we
store a 32bit cookie directly in the UBIFS directory entry node such
that we get a 64bit cookie (32bit from filename hash and the dent
cookie). For a lookup by hash UBIFS finds the entry by the first 32bit
and then compares the dent cookie. If it does not match, it has to do a
linear search of the whole directory and compares all dent cookies until
the correct entry is found.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
b91dc9816e ubifs: Rename tnc_read_node_nm
tnc_read_hashed_node() is a better name since we read a node
by a given hash, not a name.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
ca7f85be8d ubifs: Add support for encrypted symlinks
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
f4f61d2cc6 ubifs: Implement encrypted filenames
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David Gstir <david@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00
Richard Weinberger
b9bc8c7bdb ubifs: Make r5 hash binary string aware
As of now all filenames known by UBIFS are strings with a NUL
terminator. With encrypted filenames a filename can be any binary
string and the r5 function cannot search for the NUL terminator.
UBIFS always knows how long a filename is, therefore we can change
the hash function to iterate over the filename length to work
correctly with binary strings.

Signed-off-by: Richard Weinberger <richard@nod.at>
2016-12-12 23:07:38 +01:00