Commit Graph

1723 Commits

Author SHA1 Message Date
Linus Torvalds
05ef8b97dd It has been a relatively quiet cycle for documentation, but there's still a
couple of things of note:
 
  - Conversion of the NFS documentation to RST
 
  - A new document on how to help with documentation (and a maintainer
    profile entry too)
 
 Plus the usual collection of typo fixes, etc.
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Merge tag 'docs-5.6' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a relatively quiet cycle for documentation, but there's
  still a couple of things of note:

   - Conversion of the NFS documentation to RST

   - A new document on how to help with documentation (and a maintainer
     profile entry too)

  Plus the usual collection of typo fixes, etc"

* tag 'docs-5.6' of git://git.lwn.net/linux: (40 commits)
  docs: filesystems: add overlayfs to index.rst
  docs: usb: remove some broken references
  scripts/find-unused-docs: Fix massive false positives
  docs: nvdimm: use ReST notation for subsection
  zram: correct documentation about sysfs node of huge page writeback
  Documentation: zram: various fixes in zram.rst
  Add a maintainer entry profile for documentation
  Add a document on how to contribute to the documentation
  docs: Keep up with the location of NoUri
  Documentation: Call out example SYM_FUNC_* usage as x86-specific
  Documentation: nfs: fault_injection: convert to ReST
  Documentation: nfs: pnfs-scsi-server: convert to ReST
  Documentation: nfs: convert pnfs-block-server to ReST
  Documentation: nfs: idmapper: convert to ReST
  Documentation: convert nfsd-admin-interfaces to ReST
  Documentation: nfs-rdma: convert to ReST
  Documentation: nfsroot.rst: COSMETIC: refill a paragraph
  Documentation: nfsroot.txt: convert to ReST
  Documentation: convert nfs.txt to ReST
  Documentation: filesystems: convert vfat.txt to RST
  ...
2020-01-29 15:27:31 -08:00
Linus Torvalds
5307040655 Merge branch 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull adfs updates from Al Viro:
 "adfs stuff for this cycle"

* 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (42 commits)
  fs/adfs: bigdir: Fix an error code in adfs_fplus_read()
  Documentation: update adfs filesystem documentation
  fs/adfs: mostly divorse inode number from indirect disc address
  fs/adfs: super: add support for E and E+ floppy image formats
  fs/adfs: super: extract filesystem block probe
  fs/adfs: dir: remove debug in adfs_dir_update()
  fs/adfs: super: fix inode dropping
  fs/adfs: bigdir: implement directory update support
  fs/adfs: bigdir: calculate and validate directory checkbyte
  fs/adfs: bigdir: directory validation strengthening
  fs/adfs: bigdir: extract directory validation
  fs/adfs: bigdir: factor out directory entry offset calculation
  fs/adfs: newdir: split out directory commit from update
  fs/adfs: newdir: clean up adfs_f_update()
  fs/adfs: newdir: merge adfs_dir_read() into adfs_f_read()
  fs/adfs: newdir: improve directory validation
  fs/adfs: newdir: factor out directory format validation
  fs/adfs: dir: use pointers to access directory head/tails
  fs/adfs: dir: add more efficient iterate() per-format method
  fs/adfs: dir: switch to iterate_shared method
  ...
2020-01-29 11:45:09 -08:00
Linus Torvalds
6aee4badd8 Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull openat2 support from Al Viro:
 "This is the openat2() series from Aleksa Sarai.

  I'm afraid that the rest of namei stuff will have to wait - it got
  zero review the last time I'd posted #work.namei, and there had been a
  leak in the posted series I'd caught only last weekend. I was going to
  repost it on Monday, but the window opened and the odds of getting any
  review during that... Oh, well.

  Anyway, openat2 part should be ready; that _did_ get sane amount of
  review and public testing, so here it comes"

From Aleksa's description of the series:
 "For a very long time, extending openat(2) with new features has been
  incredibly frustrating. This stems from the fact that openat(2) is
  possibly the most famous counter-example to the mantra "don't silently
  accept garbage from userspace" -- it doesn't check whether unknown
  flags are present[1].

  This means that (generally) the addition of new flags to openat(2) has
  been fraught with backwards-compatibility issues (O_TMPFILE has to be
  defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
  kernels gave errors, since it's insecure to silently ignore the
  flag[2]). All new security-related flags therefore have a tough road
  to being added to openat(2).

  Furthermore, the need for some sort of control over VFS's path
  resolution (to avoid malicious paths resulting in inadvertent
  breakouts) has been a very long-standing desire of many userspace
  applications.

  This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
  (which was a variant of David Drysdale's O_BENEATH patchset[4] which
  was a spin-off of the Capsicum project[5]) with a few additions and
  changes made based on the previous discussion within [6] as well as
  others I felt were useful.

  In line with the conclusions of the original discussion of
  AT_NO_JUMPS, the flag has been split up into separate flags. However,
  instead of being an openat(2) flag it is provided through a new
  syscall openat2(2) which provides several other improvements to the
  openat(2) interface (see the patch description for more details). The
  following new LOOKUP_* flags are added:

  LOOKUP_NO_XDEV:

     Blocks all mountpoint crossings (upwards, downwards, or through
     absolute links). Absolute pathnames alone in openat(2) do not
     trigger this. Magic-link traversal which implies a vfsmount jump is
     also blocked (though magic-link jumps on the same vfsmount are
     permitted).

  LOOKUP_NO_MAGICLINKS:

     Blocks resolution through /proc/$pid/fd-style links. This is done
     by blocking the usage of nd_jump_link() during resolution in a
     filesystem. The term "magic-links" is used to match with the only
     reference to these links in Documentation/, but I'm happy to change
     the name.

     It should be noted that this is different to the scope of
     ~LOOKUP_FOLLOW in that it applies to all path components. However,
     you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
     will *not* fail (assuming that no parent component was a
     magic-link), and you will have an fd for the magic-link.

     In order to correctly detect magic-links, the introduction of a new
     LOOKUP_MAGICLINK_JUMPED state flag was required.

  LOOKUP_BENEATH:

     Disallows escapes to outside the starting dirfd's
     tree, using techniques such as ".." or absolute links. Absolute
     paths in openat(2) are also disallowed.

     Conceptually this flag is to ensure you "stay below" a certain
     point in the filesystem tree -- but this requires some additional
     to protect against various races that would allow escape using
     "..".

     Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
     can trivially beam you around the filesystem (breaking the
     protection). In future, there might be similar safety checks done
     as in LOOKUP_IN_ROOT, but that requires more discussion.

  In addition, two new flags are added that expand on the above ideas:

  LOOKUP_NO_SYMLINKS:

     Does what it says on the tin. No symlink resolution is allowed at
     all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
     can still be used with NOFOLLOW to open an fd for the symlink as
     long as no parent path had a symlink component.

  LOOKUP_IN_ROOT:

     This is an extension of LOOKUP_BENEATH that, rather than blocking
     attempts to move past the root, forces all such movements to be
     scoped to the starting point. This provides chroot(2)-like
     protection but without the cost of a chroot(2) for each filesystem
     operation, as well as being safe against race attacks that
     chroot(2) is not.

     If a race is detected (as with LOOKUP_BENEATH) then an error is
     generated, and similar to LOOKUP_BENEATH it is not permitted to
     cross magic-links with LOOKUP_IN_ROOT.

     The primary need for this is from container runtimes, which
     currently need to do symlink scoping in userspace[7] when opening
     paths in a potentially malicious container.

     There is a long list of CVEs that could have bene mitigated by
     having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
     CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
     few).

  In order to make all of the above more usable, I'm working on
  libpathrs[8] which is a C-friendly library for safe path resolution.
  It features a userspace-emulated backend if the kernel doesn't support
  openat2(2). Hopefully we can get userspace to switch to using it, and
  thus get openat2(2) support for free once it's ready.

  Future work would include implementing things like
  RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
  programs to be sure they don't hit DoSes though stale NFS handles)"

* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Documentation: path-lookup: include new LOOKUP flags
  selftests: add openat2(2) selftests
  open: introduce openat2(2) syscall
  namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
  namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
  namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
  namei: LOOKUP_NO_XDEV: block mountpoint crossing
  namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
  namei: LOOKUP_NO_SYMLINKS: block symlink resolution
  namei: allow set_root() to produce errors
  namei: allow nd_jump_link() to produce errors
  nsfs: clean-up ns_get_path() signature to return int
  namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-29 11:20:24 -08:00
Mauro Carvalho Chehab
77ce1a47eb docs: filesystems: add overlayfs to index.rst
While the document is there, it is currently missing at the
index file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/3b8e7783b1fcc71e4f94af5ea8e5fa264392f8c4.1580193653.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-28 13:41:57 -07:00
Daniel Rosenberg
edc440e3d2 fscrypt: improve format of no-key names
When an encrypted directory is listed without the key, the filesystem
must show "no-key names" that uniquely identify directory entries, are
at most 255 (NAME_MAX) bytes long, and don't contain '/' or '\0'.
Currently, for short names the no-key name is the base64 encoding of the
ciphertext filename, while for long names it's the base64 encoding of
the ciphertext filename's dirhash and second-to-last 16-byte block.

This format has the following problems:

- Since it doesn't always include the dirhash, it's incompatible with
  directories that will use a secret-keyed dirhash over the plaintext
  filenames.  In this case, the dirhash won't be computable from the
  ciphertext name without the key, so it instead must be retrieved from
  the directory entry and always included in the no-key name.
  Casefolded encrypted directories will use this type of dirhash.

- It's ambiguous: it's possible to craft two filenames that map to the
  same no-key name, since the method used to abbreviate long filenames
  doesn't use a proper cryptographic hash function.

Solve both these problems by switching to a new no-key name format that
is the base64 encoding of a variable-length structure that contains the
dirhash, up to 149 bytes of the ciphertext filename, and (if any bytes
remain) the SHA-256 of the remaining bytes of the ciphertext filename.

This ensures that each no-key name contains everything needed to find
the directory entry again, contains only legal characters, doesn't
exceed NAME_MAX, is unambiguous unless there's a SHA-256 collision, and
that we only take the performance hit of SHA-256 on very long filenames.

Note: this change does *not* address the existing issue where users can
modify the 'dirhash' part of a no-key name and the filesystem may still
accept the name.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved comments and commit message, fixed checking return value
 of base64_decode(), check for SHA-256 error, continue to set disk_name
 for short names to keep matching simpler, and many other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-7-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:50:03 -08:00
Eric Biggers
f592efe735 fscrypt: clarify what is meant by a per-file key
Now that there's sometimes a second type of per-file key (the dirhash
key), clarify some function names, macros, and documentation that
specifically deal with per-file *encryption* keys.

Link: https://lore.kernel.org/r/20200120223201.241390-4-ebiggers@kernel.org
Reviewed-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:49:56 -08:00
Daniel Rosenberg
aa408f835d fscrypt: derive dirhash key for casefolded directories
When we allow indexed directories to use both encryption and
casefolding, for the dirhash we can't just hash the ciphertext filenames
that are stored on-disk (as is done currently) because the dirhash must
be case insensitive, but the stored names are case-preserving.  Nor can
we hash the plaintext names with an unkeyed hash (or a hash keyed with a
value stored on-disk like ext4's s_hash_seed), since that would leak
information about the names that encryption is meant to protect.

Instead, if we can accept a dirhash that's only computable when the
fscrypt key is available, we can hash the plaintext names with a keyed
hash using a secret key derived from the directory's fscrypt master key.
We'll use SipHash-2-4 for this purpose.

Prepare for this by deriving a SipHash key for each casefolded encrypted
directory.  Make sure to handle deriving the key not only when setting
up the directory's fscrypt_info, but also in the case where the casefold
flag is enabled after the fscrypt_info was already set up.  (We could
just always derive the key regardless of casefolding, but that would
introduce unnecessary overhead for people not using casefolding.)

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved commit message, updated fscrypt.rst, squashed with change
 that avoids unnecessarily deriving the key, and many other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:49:55 -08:00
Daniel Rosenberg
6e1918cfb2 fscrypt: don't allow v1 policies with casefolding
Casefolded encrypted directories will use a new dirhash method that
requires a secret key.  If the directory uses a v2 encryption policy,
it's easy to derive this key from the master key using HKDF.  However,
v1 encryption policies don't provide a way to derive additional keys.

Therefore, don't allow casefolding on directories that use a v1 policy.
Specifically, make it so that trying to enable casefolding on a
directory that has a v1 policy fails, trying to set a v1 policy on a
casefolded directory fails, and trying to open a casefolded directory
that has a v1 policy (if one somehow exists on-disk) fails.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved commit message, updated fscrypt.rst, and other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:47:15 -08:00
Russell King
76ed99d199 Documentation: update adfs filesystem documentation
Add an introduction to adfs to its documentation detailing which formats
are supported by the module.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-20 20:12:42 -05:00
Aleksa Sarai
b55eef872a Documentation: path-lookup: include new LOOKUP flags
Now that we have new LOOKUP flags, we should document them in the
relevant path-walking documentation. And now that we've settled on a
common name for nd_jump_link() style symlinks ("magic links"), use that
term where magic-link semantics are described.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-18 09:19:28 -05:00
Daniel W. S. Almeida
6996e8ca8b Documentation: nfs: fault_injection: convert to ReST
Convert fault_injection.txt to ReST and move it to admin-guide.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/f7b0cf8fb1159a668f75ce82a581e7590568c2b8.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
98600b71f2 Documentation: nfs: pnfs-scsi-server: convert to ReST
Convert pnfs-scsi-server to ReST and move it to admin-guide. Content
remains mostly unchanged.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/5c4b8af41ca0a427a3987535815bccf47a65d320.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
26f6225fa5 Documentation: nfs: convert pnfs-block-server to ReST
Convert pnfs-block-server.txt to ReST and move it to admin-guide.
Content remains mostly unchanged.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/c06903760e690c16d9df92f5e75f80381d6326d8.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
fbdcd0b8e5 Documentation: nfs: idmapper: convert to ReST
Convert idmapper.txt to ReST and move it to admin-guide.
Content remains mostly unchanged otherwise.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/069e40cd551ea778538f8fe9ad15ee26e45fc748.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
0f3456ba9f Documentation: convert nfsd-admin-interfaces to ReST
Convert nfsd-admin-interfaces to ReST and move it into admin-guide.
Content remains mostly untouched.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/d471305e9c96dec38f18d2ff816fca2269a88e29.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
f8b8d03059 Documentation: nfs-rdma: convert to ReST
Convert nfs-rdma to ReST and move it to admin-guide. Content
remais mostly untouched. Also, mark the doc as obsolete.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/9c88f184f9de2a3eb5181563e258559efc02f58a.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
f9a9349846 Documentation: nfsroot.txt: convert to ReST
Convert nfsroot.txt to RST and move it to admin-guide. Content remains
mostly the same.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/442d35917351f5260dd8ed7362e9b5f1264ef8ad.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
2f123b9a35 Documentation: convert nfs.txt to ReST
This patch converts nfs.txt to RST. It also moves it to admin-guide.
The reason for moving it is because this document contains information
useful for system administrators, as noted on the following paragraph:

'The purpose of this document is to provide information on some of the
special features of the NFS client that can be configured by system
administrators'.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/cb9f2da2f2f6dd432b4cf9e05f79f74f4d54b6ab.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
a1986433a9 Documentation: filesystems: convert vfat.txt to RST
Converts vfat.txt to the reStructuredText format, improving presentation
without changing the underlying content.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
-----------------------------------------------------------
Changes in v3:
Removed unnecessary markup.
Removed section "BUG REPORTS" as recommended by the maintainer.

Changes in v2:
Refactored long lines as pointed out by Jonathan
Copied the maintainer
Updated the reference in the MAINTAINERS file for vfat

I did not move this into admin-guide, waiting on what the
maintainer has to say about this and also about old sections
in the text, if any.

Link: https://lore.kernel.org/r/20191223010030.434902-1-dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-10 10:58:45 -07:00
Eric Biggers
93edd392ca fscrypt: support passing a keyring key to FS_IOC_ADD_ENCRYPTION_KEY
Extend the FS_IOC_ADD_ENCRYPTION_KEY ioctl to allow the raw key to be
specified by a Linux keyring key, rather than specified directly.

This is useful because fscrypt keys belong to a particular filesystem
instance, so they are destroyed when that filesystem is unmounted.
Usually this is desired.  But in some cases, userspace may need to
unmount and re-mount the filesystem while keeping the keys, e.g. during
a system update.  This requires keeping the keys somewhere else too.

The keys could be kept in memory in a userspace daemon.  But depending
on the security architecture and assumptions, it can be preferable to
keep them only in kernel memory, where they are unreadable by userspace.

We also can't solve this by going back to the original fscrypt API
(where for each file, the master key was looked up in the process's
keyring hierarchy) because that caused lots of problems of its own.

Therefore, add the ability for FS_IOC_ADD_ENCRYPTION_KEY to accept a
Linux keyring key.  This solves the problem by allowing userspace to (if
needed) save the keys securely in a Linux keyring for re-provisioning,
while still using the new fscrypt key management ioctls.

This is analogous to how dm-crypt accepts a Linux keyring key, but the
key is then stored internally in the dm-crypt data structures rather
than being looked up again each time the dm-crypt device is accessed.

Use a custom key type "fscrypt-provisioning" rather than one of the
existing key types such as "logon".  This is strongly desired because it
enforces that these keys are only usable for a particular purpose: for
fscrypt as input to a particular KDF.  Otherwise, the keys could also be
passed to any kernel API that accepts a "logon" key with any service
prefix, e.g. dm-crypt, UBIFS, or (recently proposed) AF_ALG.  This would
risk leaking information about the raw key despite it ostensibly being
unreadable.  Of course, this mistake has already been made for multiple
kernel APIs; but since this is a new API, let's do it right.

This patch has been tested using an xfstest which I wrote to test it.

Link: https://lore.kernel.org/r/20191119222447.226853-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-12-31 10:33:49 -06:00
Madhuparna Bhowmik
a83aaf4979 Documentation: filesystems: automount-support: Change reference to document autofs.txt to autofs.rst
This patch fixes following documentation build warning:
Warning: Documentation/filesystems/automount-support.txt references
a file that doesn't exist: Documentation/filesystems/autofs.txt

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik04@gmail.com>
Link: https://lore.kernel.org/r/20191204101939.6939-1-madhuparnabhowmik04@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-12-19 09:35:51 -07:00
Linus Torvalds
81c64b0bd0 overlayfs fixes for 5.5-rc2
-----BEGIN PGP SIGNATURE-----
 
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Merge tag 'ovl-fixes-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs fixes from Miklos Szeredi:
 "Fix some bugs and documentation"

* tag 'ovl-fixes-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  docs: filesystems: overlayfs: Fix restview warnings
  docs: filesystems: overlayfs: Rename overlayfs.txt to .rst
  ovl: relax WARN_ON() on rename to self
  ovl: fix corner case of non-unique st_dev;st_ino
  ovl: don't use a temp buf for encoding real fh
  ovl: make sure that real fid is 32bit aligned in memory
  ovl: fix lookup failure on multi lower squashfs
2019-12-14 11:13:54 -08:00
Linus Torvalds
687dec9b94 Changes since last update:
- Fix improper return value of listxattr() with no xattr;
 
 - Keep up documentation with latest code.
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Merge tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs fixes from Gao Xiang:
 "Mainly address a regression reported by David recently observed
  together with overlayfs due to the improper return value of
  listxattr() without xattr. Update outdated expressions in document as
  well.

  Summary:

   - Fix improper return value of listxattr() with no xattr

   - Keep up documentation with latest code"

* tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: update documentation
  erofs: zero out when listxattr is called with no xattr
2019-12-11 12:25:32 -08:00
Amir Goldstein
35c6cb4168 docs: filesystems: overlayfs: Fix restview warnings
Fix only the obvious problems

[SzM: add SPDX license line]

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-12-10 16:00:55 +01:00
Amir Goldstein
5356ab0644 docs: filesystems: overlayfs: Rename overlayfs.txt to .rst
It is already formatted as RST.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-12-10 16:00:55 +01:00
Gao Xiang
ffafde4783 erofs: update documentation
Some on-disk structures, fields have been renamed in v5.4,
the corresponding document should be updated as well.

Also fix misrespresentation of file time and words about
fixed-sized output compression, data inline, etc.

Link: https://lore.kernel.org/r/20191207025509.6614-1-hsiangkao@aol.com/
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2019-12-08 21:37:01 +08:00
Linus Torvalds
937d6eefc7 Here's the main documentation changes for 5.5:
- Various kerneldoc script enhancements.
 
  - More RST conversions; those are slowing down as we run out of things to
    convert, but we're a ways from done still.
 
  - Dan's "maintainer profile entry" work landed at last.  Now we just need
    to get maintainers to fill in the profiles...
 
  - A reworking of the parallel build setup to work better with a variety of
    systems (and to not take over huge systems entirely in particular).
 
  - The MAINTAINERS file is now converted to RST during the build.
    Hopefully nobody ever tries to print this thing, or they will need to
    load a lot of paper.
 
  - A script and documentation making it easy for maintainers to add Link:
    tags at commit time.
 
 Also included is the removal of a bunch of spurious CR characters.
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Merge tag 'docs-5.5a' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "Here are the main documentation changes for 5.5:

   - Various kerneldoc script enhancements.

   - More RST conversions; those are slowing down as we run out of
     things to convert, but we're a ways from done still.

   - Dan's "maintainer profile entry" work landed at last. Now we just
     need to get maintainers to fill in the profiles...

   - A reworking of the parallel build setup to work better with a
     variety of systems (and to not take over huge systems entirely in
     particular).

   - The MAINTAINERS file is now converted to RST during the build.
     Hopefully nobody ever tries to print this thing, or they will need
     to load a lot of paper.

   - A script and documentation making it easy for maintainers to add
     Link: tags at commit time.

  Also included is the removal of a bunch of spurious CR characters"

* tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits)
  docs: remove a bunch of stray CRs
  docs: fix up the maintainer profile document
  libnvdimm, MAINTAINERS: Maintainer Entry Profile
  Maintainer Handbook: Maintainer Entry Profile
  MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile
  docs, parallelism: Rearrange how jobserver reservations are made
  docs, parallelism: Do not leak blocking mode to other readers
  docs, parallelism: Fix failure path and add comment
  Documentation: Remove bootmem_debug from kernel-parameters.txt
  Documentation: security: core.rst: fix warnings
  Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning
  Documentation/translation: Use Korean for Korean translation title
  docs/memory-barriers.txt: Remove remaining references to mmiowb()
  docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread
  docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section
  Documentation/kokr: Kill all references to mmiowb()
  docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section
  docs: Add initial documentation for devfreq
  Documentation: Document how to get links with git am
  docs: Add request_irq() documentation
  ...
2019-12-02 11:51:02 -08:00
Linus Torvalds
8f45533e9d f2fs-for-5.5-rc1
In this round, we've introduced fairly small number of patches as below.
 
 Enhancement:
  - improve the in-place-update IO flow
  - allocate segment to guarantee no GC for pinned files
 
 Bug fix:
  - fix updatetime in lazytime mode
  - potential memory leak in f2fs_listxattr
  - record parent inode number in rename2 correctly
  - fix deadlock in f2fs_gc along with atomic writes
  - avoid needless data migration in GC
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Merge tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've introduced fairly small number of patches as below.

  Enhancements:
   - improve the in-place-update IO flow
   - allocate segment to guarantee no GC for pinned files

  Bug fixes:
   - fix updatetime in lazytime mode
   - potential memory leak in f2fs_listxattr
   - record parent inode number in rename2 correctly
   - fix deadlock in f2fs_gc along with atomic writes
   - avoid needless data migration in GC"

* tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: stop GC when the victim becomes fully valid
  f2fs: expose main_blkaddr in sysfs
  f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
  f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
  f2fs: show f2fs instance in printk_ratelimited
  f2fs: fix potential overflow
  f2fs: fix to update dir's i_pino during cross_rename
  f2fs: support aligned pinned file
  f2fs: avoid kernel panic on corruption test
  f2fs: fix wrong description in document
  f2fs: cache global IPU bio
  f2fs: fix to avoid memory leakage in f2fs_listxattr
  f2fs: check total_segments from devices in raw_super
  f2fs: update multi-dev metadata in resize_fs
  f2fs: mark recovery flag correctly in read_raw_super_block()
  f2fs: fix to update time in lazytime mode
2019-11-30 11:02:30 -08:00
Linus Torvalds
50b8b3f85a This merge window saw the the following new featuers added to ext4:
* Direct I/O via iomap (required the iomap-for-next branch from Darrick
    as a prereq).
  * Support for using dioread-nolock where the block size < page size.
  * Support for encryption for file systems where the block size < page size.
  * Rework of journal credits handling so a revoke-heavy workload will
    not cause the journal to run out of space.
  * Replace bit-spinlocks with spinlocks in jbd2
 
 Also included were some bug fixes and cleanups, mostly to clean up
 corner cases from fuzzed file systems and error path handling.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "This merge window saw the the following new featuers added to ext4:

   - Direct I/O via iomap (required the iomap-for-next branch from
     Darrick as a prereq).

   - Support for using dioread-nolock where the block size < page size.

   - Support for encryption for file systems where the block size < page
     size.

   - Rework of journal credits handling so a revoke-heavy workload will
     not cause the journal to run out of space.

   - Replace bit-spinlocks with spinlocks in jbd2

  Also included were some bug fixes and cleanups, mostly to clean up
  corner cases from fuzzed file systems and error path handling"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits)
  ext4: work around deleting a file with i_nlink == 0 safely
  ext4: add more paranoia checking in ext4_expand_extra_isize handling
  jbd2: make jbd2_handle_buffer_credits() handle reserved handles
  ext4: fix a bug in ext4_wait_for_tail_page_commit
  ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails
  ext4: code cleanup for get_next_id
  ext4: fix leak of quota reservations
  ext4: remove unused variable warning in parse_options()
  ext4: Enable encryption for subpage-sized blocks
  fs/buffer.c: support fscrypt in block_read_full_page()
  ext4: Add error handling for io_end_vec struct allocation
  jbd2: Fine tune estimate of necessary descriptor blocks
  jbd2: Provide trace event for handle restarts
  ext4: Reserve revoke credits for freed blocks
  jbd2: Make credit checking more strict
  jbd2: Rename h_buffer_credits to h_total_credits
  jbd2: Reserve space for revoke descriptor blocks
  jbd2: Drop jbd2_space_needed()
  jbd2: Account descriptor blocks into t_outstanding_credits
  jbd2: Factor out common parts of stopping and restarting a handle
  ...
2019-11-30 10:53:02 -08:00
Linus Torvalds
9a3d7fd275 Driver core patches for 5.5-rc1
Here is the "big" set of driver core patches for 5.5-rc1
 
 There's a few minor cleanups and fixes in here, but the majority of the
 patches in here fall into two buckets:
   - debugfs api cleanups and fixes
   - driver core device link support for boot dependancy issues
 
 The debugfs api cleanups are working to slowly refactor the debugfs apis
 so that it is even harder to use incorrectly.  That work has been
 happening for the past few kernel releases and will continue over time,
 it's a long-term project/goal
 
 The driver core device link support missed 5.4 by just a bit, so it's
 been sitting and baking for many months now.  It's from Saravana Kannan
 to help resolve the problems that DT-based systems have at boot time
 with dependancy graphs and kernel modules.  Turns out that no one has
 actually tried to build a generic arm64 kernel with loads of modules and
 have it "just work" for a variety of platforms (like a distro kernel)
 The big problem turned out to be a lack of depandancy information
 between different areas of DT entries, and the work here resolves that
 problem and now allows devices to boot properly, and quicker than a
 monolith kernel.
 
 All of these patches have been in linux-next for a long time with no
 reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.5-rc1

  There's a few minor cleanups and fixes in here, but the majority of
  the patches in here fall into two buckets:

   - debugfs api cleanups and fixes

   - driver core device link support for boot dependancy issues

  The debugfs api cleanups are working to slowly refactor the debugfs
  apis so that it is even harder to use incorrectly. That work has been
  happening for the past few kernel releases and will continue over
  time, it's a long-term project/goal

  The driver core device link support missed 5.4 by just a bit, so it's
  been sitting and baking for many months now. It's from Saravana Kannan
  to help resolve the problems that DT-based systems have at boot time
  with dependancy graphs and kernel modules. Turns out that no one has
  actually tried to build a generic arm64 kernel with loads of modules
  and have it "just work" for a variety of platforms (like a distro
  kernel). The big problem turned out to be a lack of dependency
  information between different areas of DT entries, and the work here
  resolves that problem and now allows devices to boot properly, and
  quicker than a monolith kernel.

  All of these patches have been in linux-next for a long time with no
  reported issues"

* tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits)
  tracing: Remove unnecessary DEBUG_FS dependency
  of: property: Add device link support for interrupt-parent, dmas and -gpio(s)
  debugfs: Fix !DEBUG_FS debugfs_create_automount
  of: property: Add device link support for "iommu-map"
  of: property: Fix the semantics of of_is_ancestor_of()
  i2c: of: Populate fwnode in of_i2c_get_board_info()
  drivers: base: Fix Kconfig indentation
  firmware_loader: Fix labels with comma for builtin firmware
  driver core: Allow device link operations inside sync_state()
  driver core: platform: Declare ret variable only once
  cpu-topology: declare parse_acpi_topology in <linux/arch_topology.h>
  crypto: hisilicon: no need to check return value of debugfs_create functions
  driver core: platform: use the correct callback type for bus_find_device
  firmware_class: make firmware caching configurable
  driver core: Clarify documentation for fwnode_operations.add_links()
  mailbox: tegra: Fix superfluous IRQ error message
  net: caif: Fix debugfs on 64-bit platforms
  mac80211: Use debugfs_create_xul() helper
  media: c8sectpfe: no need to check return value of debugfs_create functions
  of: property: Add device link support for iommus, mboxes and io-channels
  ...
2019-11-27 11:06:20 -08:00
Linus Torvalds
1c1ff4836f fsverity updates for 5.5
Expose the fs-verity bit through statx().
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Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

Pull fsverity updates from Eric Biggers:
 "Expose the fs-verity bit through statx()"

* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  docs: fs-verity: mention statx() support
  f2fs: support STATX_ATTR_VERITY
  ext4: support STATX_ATTR_VERITY
  statx: define STATX_ATTR_VERITY
  docs: fs-verity: document first supported kernel version
2019-11-25 12:21:23 -08:00
Jaegeuk Kim
a4db59ac90 f2fs: expose main_blkaddr in sysfs
Expose in /sys/fs/f2fs/<blockdev>/main_blkaddr the block address where the
main area starts. This allows user mode programs to determine:

- That pinned files that are made exclusively of fully allocated 2MB
  segments will never be unpinned by the file system.

- Where the main area starts. This is required by programs that want to
  verify if a file is made exclusively of 2MB f2fs segments, the alignment
  boundary for segments starts at this address. Testing for 2MB alignment
  relative to the start of the device is incorrect, because for some
  filesystems main_blkaddr is not at a 2MB boundary relative to the start
  of the device.

The entry will be used when validating reliable pinning file feature proposed
by "f2fs: support aligned pinned file".

Signed-off-by: Ramon Pantin <pantin@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-25 10:01:27 -08:00
Jaskaran Singh
e8a9e30d72 docs: filesystems: Add mount map description in Content
The second paragraph of the content section does not properly
describe how mount points are determined by autofs.

Replace the lines detailing how the determination of these mount
points is "ad hoc" by a short description of the mount map syntax
used by autofs.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:19:59 -07:00
Jaskaran Singh
c11565e887 docs: filesystems: Update code snippets in autofs.rst
Some of the struct definitions now have an autofs packet header.
Reflect these changes by adding a definition of this header and
place it wherever suitable.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:19:53 -07:00
Jaskaran Singh
f11f2a3c54 docs: filesystems: convert autofs.txt to reST
Convert autofs.txt to reST.

The following changes abound:

- Introduce reST formatting for headings, lists et al.
- Add an indentation of an 8 space tab wherever suitable, so as
  to maintain consistency.
- Remove indentation of the description of the ioctls which are similar
  to the AUTOFS_IOC ioctls, as it does not come out quite right in HTML.
- Add an entry for autofs in the index.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:17:17 -07:00
Chandan Rajendra
196624e192 ext4: Enable encryption for subpage-sized blocks
Now that we have the code to support encryption for subpage-sized
blocks, this commit removes the conditional check in filesystem mount
code.

The commit also changes the support statement in
Documentation/filesystems/fscrypt.rst to reflect the fact that
encryption on filesystems with blocksize less than page size now works.

[EB: Tested with 'gce-xfstests -c ext4/encrypt_1k -g auto', using the
new "encrypt_1k" config I created.  All tests pass except for those that
already fail or are excluded with the encrypt or 1k configs, and 2 tests
that try to create 1023-byte symlinks which fails since encrypted
symlinks are limited to blocksize-3 bytes.  Also ran the dedicated
encryption tests using 'kvm-xfstests -c ext4/1k -g encrypt'; all pass,
including the on-disk ciphertext verification tests.]

Signed-off-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191023033312.361355-3-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2019-11-14 16:40:45 -05:00
Eric Biggers
73f0ec02d6 docs: fs-verity: mention statx() support
Document that the statx() system call can now be used to check whether a
file is a verity file.

Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-11-13 12:15:34 -08:00
Eric Biggers
c0d782a3cc docs: fs-verity: document first supported kernel version
I had meant to replace these TODOs with the actual version when applying
the patches, but forgot to do so.  Do it now.

Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-11-13 12:15:34 -08:00
Jeff Layton
ff467342d3 Documentation: atomic_open called with shared lock on non-O_CREAT open
The exclusive lock is only held when O_CREAT is set.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-07 13:17:25 -07:00
Eric Biggers
b103fb7653 fscrypt: add support for IV_INO_LBLK_64 policies
Inline encryption hardware compliant with the UFS v2.1 standard or with
the upcoming version of the eMMC standard has the following properties:

(1) Per I/O request, the encryption key is specified by a previously
    loaded keyslot.  There might be only a small number of keyslots.

(2) Per I/O request, the starting IV is specified by a 64-bit "data unit
    number" (DUN).  IV bits 64-127 are assumed to be 0.  The hardware
    automatically increments the DUN for each "data unit" of
    configurable size in the request, e.g. for each filesystem block.

Property (1) makes it inefficient to use the traditional fscrypt
per-file keys.  Property (2) precludes the use of the existing
DIRECT_KEY fscrypt policy flag, which needs at least 192 IV bits.

Therefore, add a new fscrypt policy flag IV_INO_LBLK_64 which causes the
encryption to modified as follows:

- The encryption keys are derived from the master key, encryption mode
  number, and filesystem UUID.

- The IVs are chosen as (inode_number << 32) | file_logical_block_num.
  For filenames encryption, file_logical_block_num is 0.

Since the file nonces aren't used in the key derivation, many files may
share the same encryption key.  This is much more efficient on the
target hardware.  Including the inode number in the IVs and mixing the
filesystem UUID into the keys ensures that data in different files is
nevertheless still encrypted differently.

Additionally, limiting the inode and block numbers to 32 bits and
placing the block number in the low bits maintains compatibility with
the 64-bit DUN convention (property (2) above).

Since this scheme assumes that inode numbers are stable (which may
preclude filesystem shrinking) and that inode and file logical block
numbers are at most 32-bit, IV_INO_LBLK_64 will only be allowed on
filesystems that meet these constraints.  These are acceptable
limitations for the cases where this format would actually be used.

Note that IV_INO_LBLK_64 is an on-disk format, not an implementation.
This patch just adds support for it using the existing filesystem layer
encryption.  A later patch will add support for inline encryption.

Reviewed-by: Paul Crowley <paulcrowley@google.com>
Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-11-06 12:34:36 -08:00
Geert Uytterhoeven
d3504757f3 debugfs: Add debugfs_create_xul() for hexadecimal unsigned long
The existing debugfs_create_ulong() function supports objects of
type "unsigned long", which are 32-bit or 64-bit depending on the
platform, in decimal form.  To format objects in hexadecimal, various
debugfs_create_x*() functions exist, but all of them take fixed-size
types.

Add a debugfs helper for "unsigned long" objects in hexadecimal format.
This avoids the need for users to open-code the same, or introduce
bugs when casting the value pointer to "u32 *" or "u64 *" to call
debugfs_create_x{32,64}().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20191025094130.26033-2-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-03 18:08:53 +01:00
Geert Uytterhoeven
726ce47728 Documentation: debugfs: Document debugfs helper for unsigned long values
When debugfs_create_ulong() was added, it was not documented.

Fixes: c23fe83138 ("debugfs: Add debugfs_create_ulong()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20191021150645.32440-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-03 18:08:52 +01:00
Greg Kroah-Hartman
9927c6fa3e debugfs: remove return value of debugfs_create_atomic_t()
No one checks the return value of debugfs_create_atomic_t(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Link: https://lore.kernel.org/r/20191016130332.GA28240@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-03 14:03:01 +01:00
Greg Kroah-Hartman
c7c1168909 debugfs: remove return value of debugfs_create_x8()
No one checks the return value of debugfs_create_x8(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Link: https://lore.kernel.org/r/20191011132931.1186197-5-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-02 18:09:12 +01:00
Chao Yu
4c3258b9b0 f2fs: fix wrong description in document
As reported in bugzilla, default value of DEF_RAM_THRESHOLD was fixed by
commit 29710bcf94 ("f2fs: fix wrong percentage"), however leaving wrong
description in document, fix it.

https://bugzilla.kernel.org/show_bug.cgi?id=205203

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-25 09:52:06 -07:00
Geert Uytterhoeven
98919f4c9a Documentation: debugfs: Document debugfs helper for unsigned long values
When debugfs_create_ulong() was added, it was not documented.

Fixes: c23fe83138 ("debugfs: Add debugfs_create_ulong()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-10-24 12:04:31 -06:00
Eric Biggers
4006d799d9 fscrypt: invoke crypto API for ESSIV handling
Instead of open-coding the calculations for ESSIV handling, use an ESSIV
skcipher which does all of this under the hood.  ESSIV was added to the
crypto API in v5.4.

This is based on a patch from Ard Biesheuvel, but reworked to apply
after all the fscrypt changes that went into v5.4.

Tested with 'kvm-xfstests -c ext4,f2fs -g encrypt', including the
ciphertext verification tests for v1 and v2 encryption policies.

Originally-from: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-10-21 13:22:08 -07:00
Greg Kroah-Hartman
0864c408fb debugfs: remove return value of debugfs_create_x64()
No one checks the return value of debugfs_create_x64(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Link: https://lore.kernel.org/r/20191011132931.1186197-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16 06:07:56 -07:00
Greg Kroah-Hartman
f5cb0a7e64 debugfs: remove return value of debugfs_create_x32()
No one checks the return value of debugfs_create_x32(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Link: https://lore.kernel.org/r/20191011132931.1186197-7-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16 06:07:55 -07:00
Greg Kroah-Hartman
e40d38f28c debugfs: remove return value of debugfs_create_x16()
No one checks the return value of debugfs_create_x16(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Link: https://lore.kernel.org/r/20191011132931.1186197-6-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-16 06:07:55 -07:00