ext4: fix kernel oops caused by spurious casefold flag

If an directory has the a casefold flag set without the casefold
feature set, s_encoding will not be initialized, and this will cause
the kerne

ext4: fix kernel oops caused by spurious casefold flag

If an directory has the a casefold flag set without the casefold
feature set, s_encoding will not be initialized, and this will cause
the kernel to dereference a NULL pointer. In addition to adding
checks to avoid these kernel oops, attempts to load inodes with the
casefold flag when the casefold feature is not enable will cause the
file system to be declared corrupted.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

Merge branch 'next' into for-linus

Prepare second round of input updates for 5.3 merge window.

Merge tag 'v5.2' into next

Sync up with mainline to resolve conflicts in iforce driver.

Merge branch 'next' into for-linus

Prepare input updates for 5.3 merge window.

Merge branches 'for-5.2/fixes', 'for-5.3/doc', 'for-5.3/ish', 'for-5.3/logitech' and 'for-5.3/wacom' into for-linus

Merge remote-tracking branch 'drm/drm-next' into drm-misc-next-fixes

Some fixes have been accidentally pushed to this, so I cannot fost-forward.
Required to pull in the remove-fbcon-notifiers fixes.

Merge remote-tracking branch 'drm/drm-next' into drm-misc-next-fixes

Some fixes have been accidentally pushed to this, so I cannot fost-forward.
Required to pull in the remove-fbcon-notifiers fixes.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

show more ...

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux

Merge drm/drm-next into drm-intel-next-queued

Get the HDR dependencies originally merged via drm-misc. Sync up all
i915 changes applied via other trees. And get v5.2-rc2 as the baseline.

Signed-off

Merge drm/drm-next into drm-intel-next-queued

Get the HDR dependencies originally merged via drm-misc. Sync up all
i915 changes applied via other trees. And get v5.2-rc2 as the baseline.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

show more ...

Merge drm/drm-next into drm-misc-next

Backmerging 5.2-rc1 to -misc-next for robher

Signed-off-by: Sean Paul <seanpaul@chromium.org>

Merge branch 'fixes-dra7' into fixes

Merge tag 'v5.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.2-rc1

Sync with upstream (which now contains fbdev-v5.2 changes) to
prepare a base

Merge tag 'v5.2-rc1' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.2-rc1

Sync with upstream (which now contains fbdev-v5.2 changes) to
prepare a base for fbdev-v5.3 changes.

show more ...

Merge tag 'v5.2-rc1' into spi-5.3

Linux 5.2-rc1

Merge tag 'v5.2-rc1' into regulator-5.3

Linux 5.2-rc1

Merge tag 'v5.2-rc1' into asoc-5.3

Linux 5.2-rc1

Merge tag 'v5.1' into next

Sync up with mainline to bring in the latest APIs.

Merge branch 'linus' into x86/urgent, to pick up dependent changes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
"Add as a feature case-insensitive directories (the casefold feature)
using

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
"Add as a feature case-insensitive directories (the casefold feature)
using Unicode 12.1.

Also, the usual largish number of cleanups and bug fixes"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits)
ext4: export /sys/fs/ext4/feature/casefold if Unicode support is present
ext4: fix ext4_show_options for file systems w/o journal
unicode: refactor the rule for regenerating utf8data.h
docs: ext4.rst: document case-insensitive directories
ext4: Support case-insensitive file name lookups
ext4: include charset encoding information in the superblock
MAINTAINERS: add Unicode subsystem entry
unicode: update unicode database unicode version 12.1.0
unicode: introduce test module for normalized utf8 implementation
unicode: implement higher level API for string handling
unicode: reduce the size of utf8data[]
unicode: introduce code for UTF-8 normalization
unicode: introduce UTF-8 character database
ext4: actually request zeroing of inode table after grow
ext4: cond_resched in work-heavy group loops
ext4: fix use-after-free race with debug_want_extra_isize
ext4: avoid drop reference to iloc.bh twice
ext4: ignore e_value_offs for xattrs with value-in-ea-inode
ext4: protect journal inode's blocks using block_validity
ext4: use BUG() instead of BUG_ON(1)
...

show more ...

Merge branches 'for-5.1/upstream-fixes', 'for-5.2/core', 'for-5.2/ish', 'for-5.2/logitech', 'for-5.2/macally', 'for-5.2/picolcd', 'for-5.2/sensor' and 'for-5.2/u2fzero' into for-linus

ext4: Support case-insensitive file name lookups

This patch implements the actual support for case-insensitive file name
lookups in ext4, based on the feature bit and the encoding stored in the
supe

ext4: Support case-insensitive file name lookups

This patch implements the actual support for case-insensitive file name
lookups in ext4, based on the feature bit and the encoding stored in the
superblock.

A filesystem that has the casefold feature set is able to configure
directories with the +F (EXT4_CASEFOLD_FL) attribute, enabling lookups
to succeed in that directory in a case-insensitive fashion, i.e: match
a directory entry even if the name used by userspace is not a byte per
byte match with the disk name, but is an equivalent case-insensitive
version of the Unicode string. This operation is called a
case-insensitive file name lookup.

The feature is configured as an inode attribute applied to directories
and inherited by its children. This attribute can only be enabled on
empty directories for filesystems that support the encoding feature,
thus preventing collision of file names that only differ by case.

* dcache handling:

For a +F directory, Ext4 only stores the first equivalent name dentry
used in the dcache. This is done to prevent unintentional duplication of
dentries in the dcache, while also allowing the VFS code to quickly find
the right entry in the cache despite which equivalent string was used in
a previous lookup, without having to resort to ->lookup().

d_hash() of casefolded directories is implemented as the hash of the
casefolded string, such that we always have a well-known bucket for all
the equivalencies of the same string. d_compare() uses the
utf8_strncasecmp() infrastructure, which handles the comparison of
equivalent, same case, names as well.

For now, negative lookups are not inserted in the dcache, since they
would need to be invalidated anyway, because we can't trust missing file
dentries. This is bad for performance but requires some leveraging of
the vfs layer to fix. We can live without that for now, and so does
everyone else.

* on-disk data:

Despite using a specific version of the name as the internal
representation within the dcache, the name stored and fetched from the
disk is a byte-per-byte match with what the user requested, making this
implementation 'name-preserving'. i.e. no actual information is lost
when writing to storage.

DX is supported by modifying the hashes used in +F directories to make
them case/encoding-aware. The new disk hashes are calculated as the
hash of the full casefolded string, instead of the string directly.
This allows us to efficiently search for file names in the htree without
requiring the user to provide an exact name.

* Dealing with invalid sequences:

By default, when a invalid UTF-8 sequence is identified, ext4 will treat
it as an opaque byte sequence, ignoring the encoding and reverting to
the old behavior for that unique file. This means that case-insensitive
file name lookup will not work only for that file. An optional bit can
be set in the superblock telling the filesystem code and userspace tools
to enforce the encoding. When that optional bit is set, any attempt to
create a file name using an invalid UTF-8 sequence will fail and return
an error to userspace.

* Normalization algorithm:

The UTF-8 algorithms used to compare strings in ext4 is implemented
lives in fs/unicode, and is based on a previous version developed by
SGI. It implements the Canonical decomposition (NFD) algorithm
described by the Unicode specification 12.1, or higher, combined with
the elimination of ignorable code points (NFDi) and full
case-folding (CF) as documented in fs/unicode/utf8_norm.c.

NFD seems to be the best normalization method for EXT4 because:

- It has a lower cost than NFC/NFKC (which requires
decomposing to NFD as an intermediary step)
- It doesn't eliminate important semantic meaning like
compatibility decompositions.

Although:

- This implementation is not completely linguistic accurate, because
different languages have conflicting rules, which would require the
specialization of the filesystem to a given locale, which brings all
sorts of problems for removable media and for users who use more than
one language.

Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

show more ...

Merge tag 'v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into mlx5-next

Linux 5.1-rc1

We forgot to reset the branch last merge window thus mlx5-next is outdated
and stil

Merge tag 'v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into mlx5-next

Linux 5.1-rc1

We forgot to reset the branch last merge window thus mlx5-next is outdated
and still based on 5.0-rc2. This merge commit is needed to sync mlx5-next
branch with 5.1-rc1.

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

show more ...

Merge tag 'drm-intel-next-2019-04-04' into gvt-next

Merge back drm-intel-next for engine name definition refinement
and 54939ea0bd85 ("drm/i915: Switch to use HWS indices rather than addresses")
tha

Merge tag 'drm-intel-next-2019-04-04' into gvt-next

Merge back drm-intel-next for engine name definition refinement
and 54939ea0bd85 ("drm/i915: Switch to use HWS indices rather than addresses")
that would need gvt fixes to depend on.

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

show more ...

Merge tag 'asoc-fix-v5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.1

A few core fixes along with the driver specific ones, mainly fixing

Merge tag 'asoc-fix-v5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Fixes for v5.1

A few core fixes along with the driver specific ones, mainly fixing
small issues that only affect x86 platforms for various reasons (their
unusual machine enumeration mechanisms mainly, plus a fix for error
handling in topology).

There's some of the driver fixes that look larger than they are, like
the hdmi-codec changes which resulted in an indentation change, and most
of the other large changes are for new drivers like the STM32 changes.

show more ...

Merge drm/drm-next into drm-misc-next

Finally have a reason for a backmerge other than "it's been a while"!

Backmerging drm-next to -misc-next to facilitate Rob Herring's work on
Panfrost.

Signed-

Merge drm/drm-next into drm-misc-next

Finally have a reason for a backmerge other than "it's been a while"!

Backmerging drm-next to -misc-next to facilitate Rob Herring's work on
Panfrost.

Signed-off-by: Sean Paul <seanpaul@chromium.org>

show more ...

Merge tag 'v5.1-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.1-rc3

Sync with upstream (which now contains fbdev-v5.1 changes) to
prepare a base

Merge tag 'v5.1-rc3' of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into fbdev-for-next

Linux 5.1-rc3

Sync with upstream (which now contains fbdev-v5.1 changes) to
prepare a base for fbdev-v5.2 changes.

show more ...

Merge drm/drm-next into drm-intel-next-queued

This is needed to get the fourcc code merged without conflicts.

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>