<feed xmlns='http://www.w3.org/2005/Atom'>
<title>wireguard-linux/fs/notify/inotify, branch jd/unified-crypt-queue</title>
<subtitle>WireGuard for the Linux kernel</subtitle>
<id>https://git.zx2c4.com/wireguard-linux/atom/fs/notify/inotify?h=jd%2Funified-crypt-queue</id>
<link rel='self' href='https://git.zx2c4.com/wireguard-linux/atom/fs/notify/inotify?h=jd%2Funified-crypt-queue'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/'/>
<updated>2020-03-24T10:28:00Z</updated>
<entry>
<title>fsnotify: replace inode pointer with an object id</title>
<updated>2020-03-24T10:28:00Z</updated>
<author>
<name>Amir Goldstein</name>
<email>amir73il@gmail.com</email>
</author>
<published>2020-03-19T15:10:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=dfc2d2594e4a79204a3967585245f00644b8f838'/>
<id>urn:sha1:dfc2d2594e4a79204a3967585245f00644b8f838</id>
<content type='text'>
The event inode field is used only for comparison in queue merges and
cannot be dereferenced after handle_event(), because it does not hold a
refcount on the inode.

Replace it with an abstract id to do the same thing.

Link: https://lore.kernel.org/r/20200319151022.31456-8-amir73il@gmail.com
Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
</content>
</entry>
<entry>
<title>fsnotify: use helpers to access data by data_type</title>
<updated>2020-03-23T17:19:06Z</updated>
<author>
<name>Amir Goldstein</name>
<email>amir73il@gmail.com</email>
</author>
<published>2020-03-19T15:10:12Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=aa93bdc5500cc93ba31afeda1a61610d117947ad'/>
<id>urn:sha1:aa93bdc5500cc93ba31afeda1a61610d117947ad</id>
<content type='text'>
Create helpers to access path and inode from different data types.

Link: https://lore.kernel.org/r/20200319151022.31456-5-amir73il@gmail.com
Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
</content>
</entry>
<entry>
<title>Merge tag 'selinux-pr-20190917' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux</title>
<updated>2019-09-23T18:21:04Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-23T18:21:04Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=5825a95fe92566ada2292a65de030850b5cff1da'/>
<id>urn:sha1:5825a95fe92566ada2292a65de030850b5cff1da</id>
<content type='text'>
Pull selinux updates from Paul Moore:

 - Add LSM hooks, and SELinux access control hooks, for dnotify,
   fanotify, and inotify watches. This has been discussed with both the
   LSM and fs/notify folks and everybody is good with these new hooks.

 - The LSM stacking changes missed a few calls to current_security() in
   the SELinux code; we fix those and remove current_security() for
   good.

 - Improve our network object labeling cache so that we always return
   the object's label, even when under memory pressure. Previously we
   would return an error if we couldn't allocate a new cache entry, now
   we always return the label even if we can't create a new cache entry
   for it.

 - Convert the sidtab atomic_t counter to a normal u32 with
   READ/WRITE_ONCE() and memory barrier protection.

 - A few patches to policydb.c to clean things up (remove forward
   declarations, long lines, bad variable names, etc)

* tag 'selinux-pr-20190917' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  lsm: remove current_security()
  selinux: fix residual uses of current_security() for the SELinux blob
  selinux: avoid atomic_t usage in sidtab
  fanotify, inotify, dnotify, security: add security hook for fs notifications
  selinux: always return a secid from the network caches if we find one
  selinux: policydb - rename type_val_to_struct_array
  selinux: policydb - fix some checkpatch.pl warnings
  selinux: shuffle around policydb.c to get rid of forward declarations
</content>
</entry>
<entry>
<title>fanotify, inotify, dnotify, security: add security hook for fs notifications</title>
<updated>2019-08-12T21:45:39Z</updated>
<author>
<name>Aaron Goidel</name>
<email>acgoide@tycho.nsa.gov</email>
</author>
<published>2019-08-12T15:20:00Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=ac5656d8a4cdd93cd2c74355ed12e5617817e0e7'/>
<id>urn:sha1:ac5656d8a4cdd93cd2c74355ed12e5617817e0e7</id>
<content type='text'>
As of now, setting watches on filesystem objects has, at most, applied a
check for read access to the inode, and in the case of fanotify, requires
CAP_SYS_ADMIN. No specific security hook or permission check has been
provided to control the setting of watches. Using any of inotify, dnotify,
or fanotify, it is possible to observe, not only write-like operations, but
even read access to a file. Modeling the watch as being merely a read from
the file is insufficient for the needs of SELinux. This is due to the fact
that read access should not necessarily imply access to information about
when another process reads from a file. Furthermore, fanotify watches grant
more power to an application in the form of permission events. While
notification events are solely, unidirectional (i.e. they only pass
information to the receiving application), permission events are blocking.
Permission events make a request to the receiving application which will
then reply with a decision as to whether or not that action may be
completed. This causes the issue of the watching application having the
ability to exercise control over the triggering process. Without drawing a
distinction within the permission check, the ability to read would imply
the greater ability to control an application. Additionally, mount and
superblock watches apply to all files within the same mount or superblock.
Read access to one file should not necessarily imply the ability to watch
all files accessed within a given mount or superblock.

In order to solve these issues, a new LSM hook is implemented and has been
placed within the system calls for marking filesystem objects with inotify,
fanotify, and dnotify watches. These calls to the hook are placed at the
point at which the target path has been resolved and are provided with the
path struct, the mask of requested notification events, and the type of
object on which the mark is being set (inode, superblock, or mount). The
mask and obj_type have already been translated into common FS_* values
shared by the entirety of the fs notification infrastructure. The path
struct is passed rather than just the inode so that the mount is available,
particularly for mount watches. This also allows for use of the hook by
pathname-based security modules. However, since the hook is intended for
use even by inode based security modules, it is not placed under the
CONFIG_SECURITY_PATH conditional. Otherwise, the inode-based security
modules would need to enable all of the path hooks, even though they do not
use any of them.

This only provides a hook at the point of setting a watch, and presumes
that permission to set a particular watch implies the ability to receive
all notification about that object which match the mask. This is all that
is required for SELinux. If other security modules require additional hooks
or infrastructure to control delivery of notification, these can be added
by them. It does not make sense for us to propose hooks for which we have
no implementation. The understanding that all notifications received by the
requesting application are all strictly of a type for which the application
has been granted permission shows that this implementation is sufficient in
its coverage.

Security modules wishing to provide complete control over fanotify must
also implement a security_file_open hook that validates that the access
requested by the watching application is authorized. Fanotify has the issue
that it returns a file descriptor with the file mode specified during
fanotify_init() to the watching process on event. This is already covered
by the LSM security_file_open hook if the security module implements
checking of the requested file mode there. Otherwise, a watching process
can obtain escalated access to a file for which it has not been authorized.

The selinux_path_notify hook implementation works by adding five new file
permissions: watch, watch_mount, watch_sb, watch_reads, and watch_with_perm
(descriptions about which will follow), and one new filesystem permission:
watch (which is applied to superblock checks). The hook then decides which
subset of these permissions must be held by the requesting application
based on the contents of the provided mask and the obj_type. The
selinux_file_open hook already checks the requested file mode and therefore
ensures that a watching process cannot escalate its access through
fanotify.

The watch, watch_mount, and watch_sb permissions are the baseline
permissions for setting a watch on an object and each are a requirement for
any watch to be set on a file, mount, or superblock respectively. It should
be noted that having either of the other two permissions (watch_reads and
watch_with_perm) does not imply the watch, watch_mount, or watch_sb
permission. Superblock watches further require the filesystem watch
permission to the superblock. As there is no labeled object in view for
mounts, there is no specific check for mount watches beyond watch_mount to
the inode. Such a check could be added in the future, if a suitable labeled
object existed representing the mount.

The watch_reads permission is required to receive notifications from
read-exclusive events on filesystem objects. These events include accessing
a file for the purpose of reading and closing a file which has been opened
read-only. This distinction has been drawn in order to provide a direct
indication in the policy for this otherwise not obvious capability. Read
access to a file should not necessarily imply the ability to observe read
events on a file.

Finally, watch_with_perm only applies to fanotify masks since it is the
only way to set a mask which allows for the blocking, permission event.
This permission is needed for any watch which is of this type. Though
fanotify requires CAP_SYS_ADMIN, this is insufficient as it gives implicit
trust to root, which we do not do, and does not support least privilege.

Signed-off-by: Aaron Goidel &lt;acgoide@tycho.nsa.gov&gt;
Acked-by: Casey Schaufler &lt;casey@schaufler-ca.com&gt;
Acked-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Paul Moore &lt;paul@paul-moore.com&gt;
</content>
</entry>
<entry>
<title>proc/sysctl: add shared variables for range check</title>
<updated>2019-07-19T00:08:07Z</updated>
<author>
<name>Matteo Croce</name>
<email>mcroce@redhat.com</email>
</author>
<published>2019-07-18T22:58:50Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=eec4844fae7c033a0c1fc1eb3b8517aeb8b6cc49'/>
<id>urn:sha1:eec4844fae7c033a0c1fc1eb3b8517aeb8b6cc49</id>
<content type='text'>
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range.  This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.

On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.

The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:

    $ git grep -E '\.extra[12].*&amp;(zero|one|int_max)' |wc -l
    248

Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.

This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:

    # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
    add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
    Data                                         old     new   delta
    sysctl_vals                                    -      12     +12
    __kstrtab_sysctl_vals                          -      12     +12
    max                                           14      10      -4
    int_max                                       16       -     -16
    one                                           68       -     -68
    zero                                         128      28    -100
    Total: Before=20583249, After=20583085, chg -0.00%

[mcroce@redhat.com: tipc: remove two unused variables]
  Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
  Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce &lt;mcroce@redhat.com&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Aaron Tomlin &lt;atomlin@redhat.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>memcg, fsnotify: no oom-kill for remote memcg charging</title>
<updated>2019-07-12T18:05:43Z</updated>
<author>
<name>Shakeel Butt</name>
<email>shakeelb@google.com</email>
</author>
<published>2019-07-12T03:55:52Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=ec165450968b26298bd1c373de37b0ab6d826b33'/>
<id>urn:sha1:ec165450968b26298bd1c373de37b0ab6d826b33</id>
<content type='text'>
Commit d46eb14b735b ("fs: fsnotify: account fsnotify metadata to
kmemcg") added remote memcg charging for fanotify and inotify event
objects.  The aim was to charge the memory to the listener who is
interested in the events but without triggering the OOM killer.
Otherwise there would be security concerns for the listener.

At the time, oom-kill trigger was not in the charging path.  A parallel
work added the oom-kill back to charging path i.e.  commit 29ef680ae7c2
("memcg, oom: move out_of_memory back to the charge path").  So to not
trigger oom-killer in the remote memcg, explicitly add
__GFP_RETRY_MAYFAIL to the fanotigy and inotify event allocations.

Link: http://lkml.kernel.org/r/20190514212259.156585-2-shakeelb@google.com
Signed-off-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Reviewed-by: Roman Gushchin &lt;guro@fb.com&gt;
Acked-by: Jan Kara &lt;jack@suse.cz&gt;
Cc: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Vladimir Davydov &lt;vdavydov.dev@gmail.com&gt;
Cc: Michal Hocko &lt;mhocko@suse.com&gt;
Cc: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118</title>
<updated>2019-05-24T15:39:02Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-05-23T09:14:55Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=3e0a4e85803345e31ae2d0009bedf252e43278cb'/>
<id>urn:sha1:3e0a4e85803345e31ae2d0009bedf252e43278cb</id>
<content type='text'>
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version this program is distributed in the hope that it will
  be useful but without any warranty without even the implied warranty
  of merchantability or fitness for a particular purpose see the gnu
  general public license for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Richard Fontana &lt;rfontana@redhat.com&gt;
Reviewed-by: Allison Randal &lt;allison@lohutok.net&gt;
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.032047323@linutronix.de
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>treewide: Add SPDX license identifier - Makefile/Kconfig</title>
<updated>2019-05-21T08:50:46Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-05-19T12:07:45Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1'/>
<id>urn:sha1:ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1</id>
<content type='text'>
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs</title>
<updated>2019-05-08T03:03:32Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-05-08T03:03:32Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=d27fb65bc2389621040e5107baedb94b4cccf641'/>
<id>urn:sha1:d27fb65bc2389621040e5107baedb94b4cccf641</id>
<content type='text'>
Pull misc dcache updates from Al Viro:
 "Most of this pile is putting name length into struct name_snapshot and
  making use of it.

  The beginning of this series ("ovl_lookup_real_one(): don't bother
  with strlen()") ought to have been split in two (separate switch of
  name_snapshot to struct qstr from overlayfs reaping the trivial
  benefits of that), but I wanted to avoid a rebase - by the time I'd
  spotted that it was (a) in -next and (b) close to 5.1-final ;-/"

* 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  audit_compare_dname_path(): switch to const struct qstr *
  audit_update_watch(): switch to const struct qstr *
  inotify_handle_event(): don't bother with strlen()
  fsnotify: switch send_to_group() and -&gt;handle_event to const struct qstr *
  fsnotify(): switch to passing const struct qstr * for file_name
  switch fsnotify_move() to passing const struct qstr * for old_name
  ovl_lookup_real_one(): don't bother with strlen()
  sysv: bury the broken "quietly truncate the long filenames" logics
  nsfs: unobfuscate
  unexport d_alloc_pseudo()
</content>
</entry>
<entry>
<title>inotify_handle_event(): don't bother with strlen()</title>
<updated>2019-04-26T17:55:21Z</updated>
<author>
<name>Al Viro</name>
<email>viro@zeniv.linux.org.uk</email>
</author>
<published>2019-04-26T17:55:21Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=ce163918cd330158eb1a4c2a8fddec6b2e7d6d74'/>
<id>urn:sha1:ce163918cd330158eb1a4c2a8fddec6b2e7d6d74</id>
<content type='text'>
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
</content>
</entry>
</feed>
