statfs: enforce statfs[64] structure initialization

s390's struct statfs and struct statfs64 contain padding, which
field-by-field copying does not set. Initialize the respective structs
with zeros

statfs: enforce statfs[64] structure initialization

s390's struct statfs and struct statfs64 contain padding, which
field-by-field copying does not set. Initialize the respective structs
with zeros before filling them and copying them to userspace, like it's
already done for the compat versions of these structs.

Found by KMSAN.

[agordeev@linux.ibm.com: fixed typo in patch description]
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20230504144021.808932-2-iii@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

show more ...

s390,alpha: switch to 64-bit ino_t

s390 and alpha are the only 64 bit architectures with a 32-bit ino_t.
Since this is quite unusual this causes bugs from time to time.

See e.g. commit ebce3eb2f7ef

s390,alpha: switch to 64-bit ino_t

s390 and alpha are the only 64 bit architectures with a 32-bit ino_t.
Since this is quite unusual this causes bugs from time to time.

See e.g. commit ebce3eb2f7ef ("ceph: fix inode number handling on
arches with 32-bit ino_t") for an example.

This (obviously) also prevents s390 and alpha to use 64-bit ino_t for
tmpfs. See commit b85a7a8bb573 ("tmpfs: disallow CONFIG_TMPFS_INODE64
on s390").

Therefore switch both s390 and alpha to 64-bit ino_t. This should only
have an effect on the ustat system call. To prevent ABI breakage
define struct ustat compatible to the old layout and change
sys_ustat() accordingly.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

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block: remove i_bdev

Switch the block device lookup interfaces to directly work with a dev_t
so that struct block_device references are only acquired by the
blkdev_get variants (and the blk-cgroup s

block: remove i_bdev

Switch the block device lookup interfaces to directly work with a dev_t
so that struct block_device references are only acquired by the
blkdev_get variants (and the blk-cgroup special case). This means that
we now don't need an extra reference in the inode and can generally
simplify handling of struct block_device to keep the lookups contained
in the core block layer code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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Add a "nosymfollow" mount option.

For mounts that have the new "nosymfollow" option, don't follow symlinks
when resolving paths. The new option is similar in spirit to the
existing "nodev", "noexec"

Add a "nosymfollow" mount option.

For mounts that have the new "nosymfollow" option, don't follow symlinks
when resolving paths. The new option is similar in spirit to the
existing "nodev", "noexec", and "nosuid" options, as well as to the
LOOKUP_NO_SYMLINKS resolve flag in the openat2(2) syscall. Various BSD
variants have been supporting the "nosymfollow" mount option for a long
time with equivalent implementations.

Note that symlinks may still be created on file systems mounted with
the "nosymfollow" option present. readlink() remains functional, so
user space code that is aware of symlinks can still choose to follow
them explicitly.

Setting the "nosymfollow" mount option helps prevent privileged
writers from modifying files unintentionally in case there is an
unexpected link along the accessed path. The "nosymfollow" option is
thus useful as a defensive measure for systems that need to deal with
untrusted file systems in privileged contexts.

More information on the history and motivation for this patch can be
found here:

https://sites.google.com/a/chromium.org/dev/chromium-os/chromiumos-design-docs/hardening-against-malicious-stateful-data#TOC-Restricting-symlink-traversal

Signed-off-by: Mattias Nissler <mnissler@chromium.org>
Signed-off-by: Ross Zwisler <zwisler@google.com>
Reviewed-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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vfs: Fix EOVERFLOW testing in put_compat_statfs64

Today, put_compat_statfs64() disallows nearly any field value over
2^32 if f_bsize is only 32 bits, but that makes no sense.
compat_statfs64 is ther

vfs: Fix EOVERFLOW testing in put_compat_statfs64

Today, put_compat_statfs64() disallows nearly any field value over
2^32 if f_bsize is only 32 bits, but that makes no sense.
compat_statfs64 is there for the explicit purpose of providing 64-bit
fields for f_files, f_ffree, etc. And f_bsize is always only 32 bits.

As a result, 32-bit userspace gets -EOVERFLOW for i.e. large file
counts even with -D_FILE_OFFSET_BITS=64 set.

In reality, only f_bsize and f_frsize can legitimately overflow
(fields like f_type and f_namelen should never be large), so test
only those fields.

This bug was discussed at length some time ago, and this is the proposal
Al suggested at https://lkml.org/lkml/2018/8/6/640. It seemed to get
dropped amid the discussion of other related changes, but this
part seems obviously correct on its own, so I've picked it up and
sent it, for expediency.

Fixes: 64d2ab32efe3 ("vfs: fix put_compat_statfs64() does not handle errors")
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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vfs: add vfs_get_fsid() helper

Wrapper around statfs() interface.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

kernel: add kcompat_sys_{f,}statfs64()

Using this helper allows us to avoid the in-kernel calls to the
compat_sys_{f,}statfs64() sycalls, as are necessary for parameter
mangling in arm64's compat ha

kernel: add kcompat_sys_{f,}statfs64()

Using this helper allows us to avoid the in-kernel calls to the
compat_sys_{f,}statfs64() sycalls, as are necessary for parameter
mangling in arm64's compat handling.

Following the example of ksys_* functions, kcompat_sys_* functions are
intended to be a drop-in replacement for their compat_sys_*
counterparts, with the same calling convention.

This is necessary to enable conversion of arm64's syscall handling to
use pt_regs wrappers.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>

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Rename superblock flags (MS_xyz -> SB_xyz)

This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for th

Rename superblock flags (MS_xyz -> SB_xyz)

This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

# places to look in; re security/*: it generally should *not* be
# touched (that stuff parses mount(2) arguments directly), but
# there are two places where we really deal with superblock flags.
FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
include/linux/fs.h include/uapi/linux/bfs_fs.h \
security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
# the list of MS_... constants
SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
ACTIVE NOUSER"

SED_PROG=
for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

# we want files that contain at least one of MS_...,
# with fs/namespace.c and fs/pnode.c excluded.
L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

make vfs_ustat() static

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Make statfs properly return read-only state after emergency remount

Emergency remount (sysrq-u) sets MS_RDONLY to the superblock but doesn't set
MNT_READONLY to the mount point.

Once calculate_f_fl

Make statfs properly return read-only state after emergency remount

Emergency remount (sysrq-u) sets MS_RDONLY to the superblock but doesn't set
MNT_READONLY to the mount point.

Once calculate_f_flags() only check for the mount point read only state,
when setting kstatfs flags, after an emergency remount, statfs does not
report the filesystem as read-only, even though it is.

Enable flags_by_sb() to also check for superblock read only state, so the
kstatfs and consequently statfs can properly show the read-only state of
the filesystem.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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compat statfs: switch to copy_to_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

statfs: move compat syscalls from compat.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: misc struct path constification

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: allow O_PATH file descriptors for fstatfs()

Olga reported that file descriptors opened with O_PATH do not work with
fstatfs(), found during further development of ksh93's thread support.

There

vfs: allow O_PATH file descriptors for fstatfs()

Olga reported that file descriptors opened with O_PATH do not work with
fstatfs(), found during further development of ksh93's thread support.

There is no reason to not allow O_PATH file descriptors here (fstatfs is
very much a path operation), so use "fdget_raw()". See commit
55815f70147d ("vfs: make O_PATH file descriptors usable for 'fstat()'")
for a very similar issue reported for fstat() by the same team.

Reported-and-tested-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org # O_PATH introduced in 3.0+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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vfs: fix user_statfs to retry once on ESTALE errors

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

switch simple cases of fget_light to fdget

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

switch statfs to fget_light/fput_light

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs: reduce the use of module.h wherever possible

For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete th

fs: reduce the use of module.h wherever possible

For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include. Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

show more ...

vfs: new helper - vfs_ustat()

... and bury user_get_super()/statfs_by_dentry() - they are
purely internal now.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

VFS: fix statfs() automounter semantics regression

No one in their right mind would expect statfs() to not work on a
automounter managed mount point. Fix it.

[ I'm not sure about the "no one in the

VFS: fix statfs() automounter semantics regression

No one in their right mind would expect statfs() to not work on a
automounter managed mount point. Fix it.

[ I'm not sure about the "no one in their right mind" part. It's not
mounted, and you didn't ask for it to be mounted. But nobody will
really care, and this probably makes it match previous semantics, so..
- Linus ]

This mirrors the fix made to the quota code in 815d405ceff0d69646.

Signed-off-by: Dan McGee <dpmcgee@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

clean statfs-like syscalls up

New helpers: user_statfs() and fd_statfs(), taking userland pathname and
descriptor resp. and filling struct kstatfs. Syscalls of statfs family
(native, compat and for

clean statfs-like syscalls up

New helpers: user_statfs() and fd_statfs(), taking userland pathname and
descriptor resp. and filling struct kstatfs. Syscalls of statfs family
(native, compat and foreign - osf and hpux on alpha and parisc resp.)
switched to those. Removes some boilerplate code, simplifies cleanup
on errors...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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add f_flags to struct statfs(64)

Add a flags field to help glibc implementing statvfs(3) efficiently.

We copy the flag values from glibc, and add a new ST_VALID flag to
denote that f_flags is imple

add f_flags to struct statfs(64)

Add a flags field to help glibc implementing statvfs(3) efficiently.

We copy the flag values from glibc, and add a new ST_VALID flag to
denote that f_flags is implemented.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

show more ...

pass a struct path to vfs_statfs

We'll need the path to implement the flags field for statvfs support.
We do have it available in all callers except:

- ecryptfs_statfs. This one doesn't actually

pass a struct path to vfs_statfs

We'll need the path to implement the flags field for statvfs support.
We do have it available in all callers except:

- ecryptfs_statfs. This one doesn't actually need vfs_statfs but just
needs to do a caller to the lower filesystem statfs method.
- sys_ustat. Add a non-exported statfs_by_dentry helper for it which
doesn't won't be able to fill out the flags field later on.

In addition rename the helpers for statfs vs fstatfs to do_*statfs instead
of the misleading vfs prefix.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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Take statfs variants to fs/statfs.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>