Commit Graph

550 Commits

Author SHA1 Message Date
Amir Goldstein
f17936993a fanotify: turn off support for FAN_DIR_MODIFY
FAN_DIR_MODIFY has been enabled by commit 44d705b037 ("fanotify:
report name info for FAN_DIR_MODIFY event") in 5.7-rc1. Now we are
planning further extensions to the fanotify API and during that we
realized that FAN_DIR_MODIFY may behave slightly differently to be more
consistent with extensions we plan. So until we finalize these
extensions, let's not bind our hands with exposing FAN_DIR_MODIFY to
userland.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-05-27 18:55:54 +02:00
Nathan Chancellor
6def1a1d2d fanotify: Fix the checks in fanotify_fsid_equal
Clang warns:

fs/notify/fanotify/fanotify.c:28:23: warning: self-comparison always
evaluates to true [-Wtautological-compare]
        return fsid1->val[0] == fsid1->val[0] && fsid2->val[1] == fsid2->val[1];
                             ^
fs/notify/fanotify/fanotify.c:28:57: warning: self-comparison always
evaluates to true [-Wtautological-compare]
        return fsid1->val[0] == fsid1->val[0] && fsid2->val[1] == fsid2->val[1];
                                                               ^
2 warnings generated.

The intention was clearly to compare val[0] and val[1] in the two
different fsid structs. Fix it otherwise this function always returns
true.

Fixes: afc894c784 ("fanotify: Store fanotify handles differently")
Link: https://github.com/ClangBuiltLinux/linux/issues/952
Link: https://lore.kernel.org/r/20200327171030.30625-1-natechancellor@gmail.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-30 12:40:53 +02:00
Amir Goldstein
44d705b037 fanotify: report name info for FAN_DIR_MODIFY event
Report event FAN_DIR_MODIFY with name in a variable length record similar
to how fid's are reported.  With name info reporting implemented, setting
FAN_DIR_MODIFY in mark mask is now allowed.

When events are reported with name, the reported fid identifies the
directory and the name follows the fid. The info record type for this
event info is FAN_EVENT_INFO_TYPE_DFID_NAME.

For now, all reported events have at most one info record which is
either FAN_EVENT_INFO_TYPE_FID or FAN_EVENT_INFO_TYPE_DFID_NAME (for
FAN_DIR_MODIFY).  Later on, events "on child" will report both records.

There are several ways that an application can use this information:

1. When watching a single directory, the name is always relative to
the watched directory, so application need to fstatat(2) the name
relative to the watched directory.

2. When watching a set of directories, the application could keep a map
of dirfd for all watched directories and hash the map by fid obtained
with name_to_handle_at(2).  When getting a name event, the fid in the
event info could be used to lookup the base dirfd in the map and then
call fstatat(2) with that dirfd.

3. When watching a filesystem (FAN_MARK_FILESYSTEM) or a large set of
directories, the application could use open_by_handle_at(2) with the fid
in event info to obtain dirfd for the directory where event happened and
call fstatat(2) with this dirfd.

The last option scales better for a large number of watched directories.
The first two options may be available in the future also for non
privileged fanotify watchers, because open_by_handle_at(2) requires
the CAP_DAC_READ_SEARCH capability.

Link: https://lore.kernel.org/r/20200319151022.31456-15-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 23:17:16 +01:00
Amir Goldstein
cacfb956d4 fanotify: record name info for FAN_DIR_MODIFY event
For FAN_DIR_MODIFY event, allocate a variable size event struct to store
the dir entry name along side the directory file handle.

At this point, name info reporting is not yet implemented, so trying to
set FAN_DIR_MODIFY in mark mask will return -EINVAL.

Link: https://lore.kernel.org/r/20200319151022.31456-14-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 23:17:10 +01:00
Jan Kara
01affd5471 fanotify: Drop fanotify_event_has_fid()
When some events have directory id and some object id,
fanotify_event_has_fid() becomes mostly useless and confusing because we
usually need to know which type of file handle the event has. So just
drop the function and use fanotify_event_object_fh() instead.

Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:27:16 +01:00
Amir Goldstein
d766b55361 fanotify: prepare to report both parent and child fid's
For some events, we are going to report both child and parent fid's,
so pass fsid and file handle as arguments to copy_fid_to_user(),
which is going to be called with parent and child file handles.

Link: https://lore.kernel.org/r/20200319151022.31456-13-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:27:16 +01:00
Amir Goldstein
9e2ba2c34f fanotify: send FAN_DIR_MODIFY event flavor with dir inode and name
Dirent events are going to be supported in two flavors:

1. Directory fid info + mask that includes the specific event types
   (e.g. FAN_CREATE) and an optional FAN_ONDIR flag.
2. Directory fid info + name + mask that includes only FAN_DIR_MODIFY.

To request the second event flavor, user needs to set the event type
FAN_DIR_MODIFY in the mark mask.

The first flavor is supported since kernel v5.1 for groups initialized
with flag FAN_REPORT_FID.  It is intended to be used for watching
directories in "batch mode" - the watcher is notified when directory is
changed and re-scans the directory content in response.  This event
flavor is stored more compactly in the event queue, so it is optimal
for workloads with frequent directory changes.

The second event flavor is intended to be used for watching large
directories, where the cost of re-scan of the directory on every change
is considered too high.  The watcher getting the event with the directory
fid and entry name is expected to call fstatat(2) to query the content of
the entry after the change.

Legacy inotify events are reported with name and event mask (e.g. "foo",
FAN_CREATE | FAN_ONDIR).  That can lead users to the conclusion that
there is *currently* an entry "foo" that is a sub-directory, when in fact
"foo" may be negative or non-dir by the time user gets the event.

To make it clear that the current state of the named entry is unknown,
when reporting an event with name info, fanotify obfuscates the specific
event types (e.g. create,delete,rename) and uses a common event type -
FAN_DIR_MODIFY to describe the change.  This should make it harder for
users to make wrong assumptions and write buggy filesystem monitors.

At this point, name info reporting is not yet implemented, so trying to
set FAN_DIR_MODIFY in mark mask will return -EINVAL.

Link: https://lore.kernel.org/r/20200319151022.31456-12-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:27:16 +01:00
Jan Kara
7088f35720 fanotify: divorce fanotify_path_event and fanotify_fid_event
Breakup the union and make them both inherit from abstract fanotify_event.

fanotify_path_event, fanotify_fid_event and fanotify_perm_event inherit
from fanotify_event.

type field in abstract fanotify_event determines the concrete event type.

fanotify_path_event, fanotify_fid_event and fanotify_perm_event are
allocated from separate memcache pools.

Rename fanotify_perm_event casting macro to FANOTIFY_PERM(), so that
FANOTIFY_PE() and FANOTIFY_FE() can be used as casting macros to
fanotify_path_event and fanotify_fid_event.

[JK: Cleanup FANOTIFY_PE() and FANOTIFY_FE() to be proper inline
functions and remove requirement that fanotify_event is the first in
event structures]

Link: https://lore.kernel.org/r/20200319151022.31456-11-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:27:16 +01:00
Jan Kara
afc894c784 fanotify: Store fanotify handles differently
Currently, struct fanotify_fid groups fsid and file handle and is
unioned together with struct path to save space. Also there is fh_type
and fh_len directly in struct fanotify_event to avoid padding overhead.
In the follwing patches, we will be adding more event types and this
packing makes code difficult to follow. So unpack everything and create
struct fanotify_fh which groups members logically related to file handle
to make code easier to follow. In the following patch we will pack
things again differently to make events smaller.

Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:27:16 +01:00
Jan Kara
a741c2febe fanotify: Simplify create_fd()
create_fd() is never used with invalid path. Also the only thing it
needs to know from fanotify_event is the path. Simplify the function to
take path directly and assume it is correct.

Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-25 10:22:54 +01:00
Amir Goldstein
55bf882c7f fanotify: fix merging marks masks with FAN_ONDIR
Change the logic of FAN_ONDIR in two ways that are similar to the logic
of FAN_EVENT_ON_CHILD, that was fixed in commit 54a307ba8d ("fanotify:
fix logic of events on child"):

1. The flag is meaningless in ignore mask
2. The flag refers only to events in the mask of the mark where it is set

This is what the fanotify_mark.2 man page says about FAN_ONDIR:
"Without this flag, only events for files are created."  It doesn't
say anything about setting this flag in ignore mask to stop getting
events on directories nor can I think of any setup where this capability
would be useful.

Currently, when marks masks are merged, the FAN_ONDIR flag set in one
mark affects the events that are set in another mark's mask and this
behavior causes unexpected results.  For example, a user adds a mark on a
directory with mask FAN_ATTRIB | FAN_ONDIR and a mount mark with mask
FAN_OPEN (without FAN_ONDIR).  An opendir() of that directory (which is
inside that mount) generates a FAN_OPEN event even though neither of the
marks requested to get open events on directories.

Link: https://lore.kernel.org/r/20200319151022.31456-10-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-24 12:06:32 +01:00
Amir Goldstein
f367a62a7c fanotify: merge duplicate events on parent and child
With inotify, when a watch is set on a directory and on its child, an
event on the child is reported twice, once with wd of the parent watch
and once with wd of the child watch without the filename.

With fanotify, when a watch is set on a directory and on its child, an
event on the child is reported twice, but it has the exact same
information - either an open file descriptor of the child or an encoded
fid of the child.

The reason that the two identical events are not merged is because the
object id used for merging events in the queue is the child inode in one
event and parent inode in the other.

For events with path or dentry data, use the victim inode instead of the
watched inode as the object id for event merging, so that the event
reported on parent will be merged with the event reported on the child.

Link: https://lore.kernel.org/r/20200319151022.31456-9-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-24 11:29:12 +01:00
Amir Goldstein
dfc2d2594e fsnotify: replace inode pointer with an object id
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 <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-24 11:28:00 +01:00
Amir Goldstein
017de65fe5 fsnotify: simplify arguments passing to fsnotify_parent()
Instead of passing both dentry and path and having to figure out which
one to use, pass data/data_type to simplify the code.

Link: https://lore.kernel.org/r/20200319151022.31456-6-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-23 18:22:48 +01:00
Amir Goldstein
aa93bdc550 fsnotify: use helpers to access data by data_type
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 <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-03-23 18:19:06 +01:00
Eric Sandeen
1edc8eb2e9 fs: call fsnotify_sb_delete after evict_inodes
When a filesystem is unmounted, we currently call fsnotify_sb_delete()
before evict_inodes(), which means that fsnotify_unmount_inodes()
must iterate over all inodes on the superblock looking for any inodes
with watches.  This is inefficient and can lead to livelocks as it
iterates over many unwatched inodes.

At this point, SB_ACTIVE is gone and dropping refcount to zero kicks
the inode out out immediately, so anything processed by
fsnotify_sb_delete / fsnotify_unmount_inodes gets evicted in that loop.

After that, the call to evict_inodes will evict everything else with a
zero refcount.

This should speed things up overall, and avoid livelocks in
fsnotify_unmount_inodes().

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-18 00:03:01 -05:00
Eric Sandeen
04646aebd3 fs: avoid softlockups in s_inodes iterators
Anything that walks all inodes on sb->s_inodes list without rescheduling
risks softlockups.

Previous efforts were made in 2 functions, see:

c27d82f fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
ac05fbb inode: don't softlockup when evicting inodes

but there hasn't been an audit of all walkers, so do that now.  This
also consistently moves the cond_resched() calls to the bottom of each
loop in cases where it already exists.

One loop remains: remove_dquot_ref(), because I'm not quite sure how
to deal with that one w/o taking the i_lock.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-18 00:03:01 -05:00
Linus Torvalds
0da522107e compat_ioctl: remove most of fs/compat_ioctl.c
As part of the cleanup of some remaining y2038 issues, I came to
 fs/compat_ioctl.c, which still has a couple of commands that need support
 for time64_t.
 
 In completely unrelated work, I spent time on cleaning up parts of this
 file in the past, moving things out into drivers instead.
 
 After Al Viro reviewed an earlier version of this series and did a lot
 more of that cleanup, I decided to try to completely eliminate the rest
 of it and move it all into drivers.
 
 This series incorporates some of Al's work and many patches of my own,
 but in the end stops short of actually removing the last part, which is
 the scsi ioctl handlers. I have patches for those as well, but they need
 more testing or possibly a rewrite.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABCAAGBQJdsHCdAAoJEJpsee/mABjZtYkP/1JGl3jFv3Iq/5BCdPkaePP1
 RtMJRNfURgK3GeuHUui330PvVjI/pLWXU/VXMK2MPTASpJLzYz3uCaZrpVWEMpDZ
 +ImzGmgJkITlW1uWU3zOcQhOxTyb1hCZ0Ci+2xn9QAmyOL7prXoXCXDWv3h6iyiF
 lwG+nW+HNtyx41YG+9bRfKNoG0ZJ+nkJ70BV6u0acQHXWn7Xuupa9YUmBL87hxAL
 6dlJfLTJg6q8QSv/Q6LxslfWk2Ti8OOJZOwtFM5R8Bgl0iUcvshiRCKfv/3t9jXD
 dJNvF1uq8z+gracWK49Qsfq5dnZ2ZxHFUo9u0NjbCrxNvWH/sdvhbaUBuJI75seH
 VIznCkdxFhrqitJJ8KmxANxG08u+9zSKjSlxG2SmlA4qFx/AoStoHwQXcogJscNb
 YIXYKmWBvwPzYu09QFAXdHFPmZvp/3HhMWU6o92lvDhsDwzkSGt3XKhCJea4DCaT
 m+oCcoACqSWhMwdbJOEFofSub4bY43s5iaYuKes+c8O261/Dwg6v/pgIVez9mxXm
 TBnvCsotq5m8wbwzv99eFqGeJH8zpDHrXxEtRR5KQqMqjLq/OQVaEzmpHZTEuK7n
 e/V/PAKo2/V63g4k6GApQXDxnjwT+m0aWToWoeEzPYXS6KmtWC91r4bWtslu3rdl
 bN65armTm7bFFR32Avnu
 =lgCl
 -----END PGP SIGNATURE-----

Merge tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
 "As part of the cleanup of some remaining y2038 issues, I came to
  fs/compat_ioctl.c, which still has a couple of commands that need
  support for time64_t.

  In completely unrelated work, I spent time on cleaning up parts of
  this file in the past, moving things out into drivers instead.

  After Al Viro reviewed an earlier version of this series and did a lot
  more of that cleanup, I decided to try to completely eliminate the
  rest of it and move it all into drivers.

  This series incorporates some of Al's work and many patches of my own,
  but in the end stops short of actually removing the last part, which
  is the scsi ioctl handlers. I have patches for those as well, but they
  need more testing or possibly a rewrite"

* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
  scsi: sd: enable compat ioctls for sed-opal
  pktcdvd: add compat_ioctl handler
  compat_ioctl: move SG_GET_REQUEST_TABLE handling
  compat_ioctl: ppp: move simple commands into ppp_generic.c
  compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
  compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
  compat_ioctl: unify copy-in of ppp filters
  tty: handle compat PPP ioctls
  compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
  compat_ioctl: handle SIOCOUTQNSD
  af_unix: add compat_ioctl support
  compat_ioctl: reimplement SG_IO handling
  compat_ioctl: move WDIOC handling into wdt drivers
  fs: compat_ioctl: move FITRIM emulation into file systems
  gfs2: add compat_ioctl support
  compat_ioctl: remove unused convert_in_user macro
  compat_ioctl: remove last RAID handling code
  compat_ioctl: remove /dev/raw ioctl translation
  compat_ioctl: remove PCI ioctl translation
  compat_ioctl: remove joystick ioctl translation
  ...
2019-12-01 13:46:15 -08:00
Arnd Bergmann
1832f2d8ff compat_ioctl: move more drivers to compat_ptr_ioctl
The .ioctl and .compat_ioctl file operations have the same prototype so
they can both point to the same function, which works great almost all
the time when all the commands are compatible.

One exception is the s390 architecture, where a compat pointer is only
31 bit wide, and converting it into a 64-bit pointer requires calling
compat_ptr(). Most drivers here will never run in s390, but since we now
have a generic helper for it, it's easy enough to use it consistently.

I double-checked all these drivers to ensure that all ioctl arguments
are used as pointers or are ignored, but are not interpreted as integer
values.

Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Darren Hart (VMware) <dvhart@infradead.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-10-23 17:23:44 +02:00
Ben Dooks (Codethink)
ddd06c36bd fsnotify/fdinfo: exportfs_encode_inode_fh() takes pointer as 4th argument
The call to exportfs_encode_inode_fh() takes an pointer
as the 4th argument, so replace the integer 0 with the
NULL pointer.

This fixes the following sparse warning:

fs/notify/fdinfo.c:53:87: warning: Using plain integer as NULL pointer

Link: https://lore.kernel.org/r/20191016095955.3347-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-17 10:32:59 +02:00
Ben Dooks
4a0b20be60 fsnotify: move declaration of fsnotify_mark_connector_cachep to fsnotify.h
Move fsnotify_mark_connector_cachep to fsnotify.h to properly
share it with the user in mark.c and avoid the following warning
from sparse:

fs/notify/mark.c:82:19: warning: symbol 'fsnotify_mark_connector_cachep' was not declared. Should it be static?

Link: https://lore.kernel.org/r/20191015132518.21819-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-10-17 10:31:12 +02:00
Linus Torvalds
298fb76a55 Highlights:
- add a new knfsd file cache, so that we don't have to open and
 	  close on each (NFSv2/v3) READ or WRITE.  This can speed up
 	  read and write in some cases.  It also replaces our readahead
 	  cache.
 	- Prevent silent data loss on write errors, by treating write
 	  errors like server reboots for the purposes of write caching,
 	  thus forcing clients to resend their writes.
 	- Tweak the code that allocates sessions to be more forgiving,
 	  so that NFSv4.1 mounts are less likely to hang when a server
 	  already has a lot of clients.
 	- Eliminate an arbitrary limit on NFSv4 ACL sizes; they should
 	  now be limited only by the backend filesystem and the
 	  maximum RPC size.
 	- Allow the server to enforce use of the correct kerberos
 	  credentials when a client reclaims state after a reboot.
 
 And some miscellaneous smaller bugfixes and cleanup.
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCAAzFiEEYtFWavXG9hZotryuJ5vNeUKO4b4FAl2OoFcVHGJmaWVsZHNA
 ZmllbGRzZXMub3JnAAoJECebzXlCjuG+dRoP/3OW1NxPjpjbCQWZL0M+O3AYJJla
 W8E+uoZKMosFEe/ymokMD0Vn5s47jPaMCifMjHZa2GygW8zHN9X2v0HURx/lob+o
 /rJXwMn78N/8kdbfDz2FvaCPeT0IuNzRIFBV8/sSXofqwCBwvPo+cl0QGrd4/xLp
 X35qlupx62TRk+kbdRjvv8kpS5SJ7BvR+FSA1WubNYWw2hpdEsr2OCFdGq2Wvthy
 DK6AfGBXfJGsOE+HGCSj6ejRV6i0UOJ17P8gRSsx+YT0DOe5E7ROjt+qvvRwk489
 wmR8Vjuqr1e40eGAUq3xuLfk5F5NgycY4ekVxk/cTVFNwWcz2DfdjXQUlyPAbrSD
 SqIyxN1qdKT24gtr7AHOXUWJzBYPWDgObCVBXUGzyL81RiDdhf38HRNjL2TcSDld
 tzCjQ0wbPw+iT74v6qQRY05oS+h3JOtDjU4pxsBnxVtNn4WhGJtaLfWW8o1C1QwU
 bc4aX3TlYhDmzU7n7Zjt4rFXGJfyokM+o6tPao1Z60Pmsv1gOk4KQlzLtW/jPHx4
 ZwYTwVQUKRDBfC62nmgqDyGI3/Qu11FuIxL2KXUCgkwDxNWN4YkwYjOGw9Lb5qKM
 wFpxq6CDNZB/IWLEu8Yg85kDPPUJMoI657lZb7Osr/MfBpU0YljcMOIzLBy8uV1u
 9COUbPaQipiWGu/0
 =diBo
 -----END PGP SIGNATURE-----

Merge tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new knfsd file cache, so that we don't have to open and close
     on each (NFSv2/v3) READ or WRITE. This can speed up read and write
     in some cases. It also replaces our readahead cache.

   - Prevent silent data loss on write errors, by treating write errors
     like server reboots for the purposes of write caching, thus forcing
     clients to resend their writes.

   - Tweak the code that allocates sessions to be more forgiving, so
     that NFSv4.1 mounts are less likely to hang when a server already
     has a lot of clients.

   - Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be
     limited only by the backend filesystem and the maximum RPC size.

   - Allow the server to enforce use of the correct kerberos credentials
     when a client reclaims state after a reboot.

  And some miscellaneous smaller bugfixes and cleanup"

* tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits)
  sunrpc: clean up indentation issue
  nfsd: fix nfs read eof detection
  nfsd: Make nfsd_reset_boot_verifier_locked static
  nfsd: degraded slot-count more gracefully as allocation nears exhaustion.
  nfsd: handle drc over-allocation gracefully.
  nfsd: add support for upcall version 2
  nfsd: add a "GetVersion" upcall for nfsdcld
  nfsd: Reset the boot verifier on all write I/O errors
  nfsd: Don't garbage collect files that might contain write errors
  nfsd: Support the server resetting the boot verifier
  nfsd: nfsd_file cache entries should be per net namespace
  nfsd: eliminate an unnecessary acl size limit
  Deprecate nfsd fault injection
  nfsd: remove duplicated include from filecache.c
  nfsd: Fix the documentation for svcxdr_tmpalloc()
  nfsd: Fix up some unused variable warnings
  nfsd: close cached files prior to a REMOVE or RENAME that would replace target
  nfsd: rip out the raparms cache
  nfsd: have nfsd_test_lock use the nfsd_file cache
  nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache
  ...
2019-09-27 17:00:27 -07:00
Linus Torvalds
5825a95fe9 selinux/stable-5.4 PR 20190917
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAl2BLvcUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXP9pA/+Ls9sRGZoEipycbgRnwkL9/6yFtn4
 UCFGMP0eobrjL82i8uMOa/72Budsp3ZaZRxf36NpbMDPyB9ohp5jf7o1WFTELESv
 EwxVvOMNwrxO2UbzRv3iywnhdPVJ4gHPa4GWfBHu2EEfhz3/Bv0tPIBdeXAbq4aC
 R0p+M9X0FFEp9eP4ftwOvFGpbZ8zKo1kwgdvCnqLhHDkyqtapqO/ByCTe1VATERP
 fyxjYDZNnITmI0plaIxCeeudklOTtVSAL4JPh1rk8rZIkUznZ4EBDHxdKiaz3j9C
 ZtAthiAA9PfAwf4DZSPHnGsfINxeNBKLD65jZn/PUne/gNJEx4DK041X9HXBNwjv
 OoArw58LCzxtTNZ//WB4CovRpeSdKvmKv0oh61k8cdQahLeHhzXE1wLQbnnBJLI3
 CTsumIp4ZPEOX5r4ogdS3UIQpo3KrZump7VO85yUTRni150JpZR3egYpmcJ0So1A
 QTPemBhC2CHJVTpycYZ9fVTlPeC4oNwosPmvpB8XeGu3w5JpuNSId+BDR/ZlQAmq
 xWiIocGL3UMuPuJUrTGChifqBAgzK+gLa7S7RYPEnTCkj6LVQwsuP4gBXf75QTG4
 FPwVcoMSDFxUDF0oFqwz4GfJlCxBSzX+BkWUn6jIiXKXBnQjU+1gu6KTwE25mf/j
 snJznFk25hFYFaM=
 =n4ht
 -----END PGP SIGNATURE-----

Merge tag 'selinux-pr-20190917' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

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
2019-09-23 11:21:04 -07:00
Trond Myklebust
b72679ee89 notify: export symbols for use by the knfsd file cache
The knfsd file cache will need to detect when files are unlinked, so that
it can close the associated cached files. Export a minimal set of notifier
functions to allow it to do so.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:00:39 -04:00
Aaron Goidel
ac5656d8a4 fanotify, inotify, dnotify, security: add security hook for fs notifications
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 <acgoide@tycho.nsa.gov>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2019-08-12 17:45:39 -04:00
Matteo Croce
eec4844fae proc/sysctl: add shared variables for range check
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].*&(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 <mcroce@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-18 17:08:07 -07:00
Shakeel Butt
ec16545096 memcg, fsnotify: no oom-kill for remote memcg charging
Commit d46eb14b73 ("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 29ef680ae7
("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 <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-12 11:05:43 -07:00
Linus Torvalds
e6983afd92 \n
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAl0kWgwACgkQnJ2qBz9k
 QNkkdggA7bdy6xZRPdumZMxtASGDs1JJ4diNs+apgyc6wUfsT1lCE2ap20EdzfzK
 drAvlJt1vYEW+6apOzUXJ0qWXMVRzy4XRl+jVMO9GW6BoY4OyJQ86AQZlEv1zZ4n
 vxeYnlbxA7JyfkWgup0ZSb5EKRSO1eSxZKEZou0wu2jRCRr/E5RyjPQHXaiE5ihc
 7ilEtTI3Qg3nnAK30F0Iy0X3lGqgXj+rlJ0TgR8BBEDllct2wV16vvMl/Sy+BXip
 5sSWjSy8zntMnkSN8yH/oJN0D+fqmCsnYafwqTpPek8izvEz4xpjshbWTDnPm0HM
 eiMC1U3ZJoD3Z4/wxRZ91m60VYgJBA==
 =SVKR
 -----END PGP SIGNATURE-----

Merge tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "This contains cleanups of the fsnotify name removal hook and also a
  patch to disable fanotify permission events for 'proc' filesystem"

* tag 'fsnotify_for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: get rid of fsnotify_nameremove()
  fsnotify: move fsnotify_nameremove() hook out of d_delete()
  configfs: call fsnotify_rmdir() hook
  debugfs: call fsnotify_{unlink,rmdir}() hooks
  debugfs: simplify __debugfs_remove_file()
  devpts: call fsnotify_unlink() hook
  tracefs: call fsnotify_{unlink,rmdir}() hooks
  rpc_pipefs: call fsnotify_{unlink,rmdir}() hooks
  btrfs: call fsnotify_rmdir() hook
  fsnotify: add empty fsnotify_{unlink,rmdir}() hooks
  fanotify: Disallow permission events for proc filesystem
2019-07-10 20:09:17 -07:00
Amir Goldstein
7377f5bec1 fsnotify: get rid of fsnotify_nameremove()
For all callers of fsnotify_{unlink,rmdir}(), we made sure that d_parent
and d_name are stable.  Therefore, fsnotify_{unlink,rmdir}() do not need
the safety measures in fsnotify_nameremove() to stabilize parent and name.
We can now simplify those hooks and get rid of fsnotify_nameremove().

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-20 14:47:54 +02:00
Amir Goldstein
c285a2f01d fanotify: update connector fsid cache on add mark
When implementing connector fsid cache, we only initialized the cache
when the first mark added to object was added by FAN_REPORT_FID group.
We forgot to update conn->fsid when the second mark is added by
FAN_REPORT_FID group to an already attached connector without fsid
cache.

Reported-and-tested-by: syzbot+c277e8e2f46414645508@syzkaller.appspotmail.com
Fixes: 77115225ac ("fanotify: cache fsid in fsnotify_mark_connector")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-19 15:53:58 +02:00
Jan Kara
0b3b094ac9 fanotify: Disallow permission events for proc filesystem
Proc filesystem has special locking rules for various files. Thus
fanotify which opens files on event delivery can easily deadlock
against another process that waits for fanotify permission event to be
handled. Since permission events on /proc have doubtful value anyway,
just disallow them.

Link: https://lore.kernel.org/linux-fsdevel/20190320131642.GE9485@quack2.suse.cz/
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-28 18:10:07 +02:00
Thomas Gleixner
3e0a4e8580 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118
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 <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.032047323@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:02 +02:00
Thomas Gleixner
c82ee6d3be treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18
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 you should have received a
  copy of the gnu general public license along with this program see
  the file copying if not write to the free software foundation 675
  mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 52 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154042.342335923@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:46 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
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 <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
d4c608115c \n
-----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAlzZmHgACgkQnJ2qBz9k
 QNleKQf/VglDfB2VvuYnMbZp4YBPZgNMe0KlOTYE60RBg4DGZj04ov0bxSRZccPP
 KvHp1ZyIM4Bp67lKFZoI6bYd5diq7gVjHIdHrFc0LfDmpyaodqxe3bOMWT/TH0YU
 0jjr7MU1wmVRY8UYrIqPIlL6Dl0hlxGf5cYPzoRQB4hzNWEWr9ZEdC1DbKupWTk/
 1GsYtCHZzpZ20YfzDU3jcYaHRVZDwZXb65Wx3OfUVof8q9bkpHd5lhl79jT4yVPS
 yYfqs1CW6ra2zsYDtBdmh46BZ3d36ACfcjmgf2/7GMdQP8Ocv0c5lnSSkrJeC5XO
 GttTFIKU7JWFAqiWmPAoGIchUXNkRA==
 =eSpi
 -----END PGP SIGNATURE-----

Merge tag 'fsnotify_for_v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify fixes from Jan Kara:
 "Two fsnotify fixes"

* tag 'fsnotify_for_v5.2-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: fix unlink performance regression
  fsnotify: Clarify connector assignment in fsnotify_add_mark_list()
2019-05-13 15:08:16 -07:00
Amir Goldstein
4d8e7055a4 fsnotify: fix unlink performance regression
__fsnotify_parent() has an optimization in place to avoid unneeded
take_dentry_name_snapshot().  When fsnotify_nameremove() was changed
not to call __fsnotify_parent(), we left out the optimization.
Kernel test robot reported a 5% performance regression in concurrent
unlink() workload.

Reported-by: kernel test robot <rong.a.chen@intel.com>
Link: https://lore.kernel.org/lkml/20190505062153.GG29809@shao2-debian/
Link: https://lore.kernel.org/linux-fsdevel/20190104090357.GD22409@quack2.suse.cz/
Fixes: 5f02a87763 ("fsnotify: annotate directory entry modification events")
CC: stable@vger.kernel.org
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-09 12:44:00 +02:00
Linus Torvalds
d27fb65bc2 Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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 ->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()
2019-05-07 20:03:32 -07:00
Linus Torvalds
eac7078a0f pidfd patches for v5.2-rc1
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE7btrcuORLb1XUhEwjrBW1T7ssS0FAlzReuoACgkQjrBW1T7s
 sS1uvBAA16pgnhRNxNTrp3LYft6lUWmF4n0baOTVtQNLhPjpwaOxHIrCBugkQCJB
 QcQ9IQSOvIkaEW0XAQoPBaeLviiKhHOFw1Fv89OtW6xUidSfSV15lcI9f1F2pCm2
 4yCL/8XvL6M0NhxiwftJAkWOXeDNLfjFnLwyLxBfgg3EeyqMgUB8raeosEID0ORR
 gm2/g8DYS2r+KNqM/F4xvMSgabfi2bGk+8BtAaVnftJfstpRNrqKwWnSK3Wspj1l
 5gkb8gSsiY6ns3V6RgNHrFlhevFg8V+VjcJt7FR+aUEjOkcoiXas/PhvamMzdsn/
 FM1F/A0pM8FSybIUClhnnnxNPc+p8ZN/71YQAPs+Mnh3xvbtKea2lkhC+Xv4OpK3
 edutSZWFaiIery82Rk00H3vqiSF1+kRIXSpZSS4mElk4FsVljkyH+nSP7rbmE2MR
 EQe+kKnZl8QzWrVbnODC+EVvvVpA2bXDvENJmvKqus+t2G0OdV7Iku3F5E3KjF8k
 S5RRV1zuBF3ugqnjmYrVmJtpEA8mxClmqvg6okru+qW6ngO5oOgVpPLjWn1CXcdj
 wcuQ6Pe1QwAHS54e9WSWgCHVssLvm9nCdCqypdNaoyGWmbTWntwlrY7Y0JUQnAbB
 6/G/DQQiCWY9y8bMZlTEydhIpgcsdROuPYv+oHF5+eQQthsWwHc=
 =LH11
 -----END PGP SIGNATURE-----

Merge tag 'pidfd-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull pidfd updates from Christian Brauner:
 "This patchset makes it possible to retrieve pidfds at process creation
  time by introducing the new flag CLONE_PIDFD to the clone() system
  call. Linus originally suggested to implement this as a new flag to
  clone() instead of making it a separate system call.

  After a thorough review from Oleg CLONE_PIDFD returns pidfds in the
  parent_tidptr argument. This means we can give back the associated pid
  and the pidfd at the same time. Access to process metadata information
  thus becomes rather trivial.

  As has been agreed, CLONE_PIDFD creates file descriptors based on
  anonymous inodes similar to the new mount api. They are made
  unconditional by this patchset as they are now needed by core kernel
  code (vfs, pidfd) even more than they already were before (timerfd,
  signalfd, io_uring, epoll etc.). The core patchset is rather small.
  The bulky looking changelist is caused by David's very simple changes
  to Kconfig to make anon inodes unconditional.

  A pidfd comes with additional information in fdinfo if the kernel
  supports procfs. The fdinfo file contains the pid of the process in
  the callers pid namespace in the same format as the procfs status
  file, i.e. "Pid:\t%d".

  To remove worries about missing metadata access this patchset comes
  with a sample/test program that illustrates how a combination of
  CLONE_PIDFD and pidfd_send_signal() can be used to gain race-free
  access to process metadata through /proc/<pid>.

  Further work based on this patchset has been done by Joel. His work
  makes pidfds pollable. It finished too late for this merge window. I
  would prefer to have it sitting in linux-next for a while and send it
  for inclusion during the 5.3 merge window"

* tag 'pidfd-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  samples: show race-free pidfd metadata access
  signal: support CLONE_PIDFD with pidfd_send_signal
  clone: add CLONE_PIDFD
  Make anon_inodes unconditional
2019-05-07 12:30:24 -07:00
Jan Kara
11a6f8e2db fsnotify: Clarify connector assignment in fsnotify_add_mark_list()
Add a comment explaining why WRITE_ONCE() is enough when setting
mark->connector which can get dereferenced by RCU protected readers.

Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-01 18:05:11 +02:00
Jan Kara
b1da6a5187 fsnotify: Fix NULL ptr deref in fanotify_get_fsid()
fanotify_get_fsid() is reading mark->connector->fsid under srcu. It can
happen that it sees mark not fully initialized or mark that is already
detached from the object list. In these cases mark->connector
can be NULL leading to NULL ptr dereference. Fix the problem by
being careful when reading mark->connector and check it for being NULL.
Also use WRITE_ONCE when writing the mark just to prevent compiler from
doing something stupid.

Reported-by: syzbot+15927486a4f1bfcbaf91@syzkaller.appspotmail.com
Fixes: 77115225ac ("fanotify: cache fsid in fsnotify_mark_connector")
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-28 22:14:50 +02:00
Al Viro
ce163918cd inotify_handle_event(): don't bother with strlen()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26 13:55:21 -04:00
Al Viro
e43e9c339a fsnotify: switch send_to_group() and ->handle_event to const struct qstr *
note that conditions surrounding accesses to dname in audit_watch_handle_event()
and audit_mark_handle_event() guarantee that dname won't have been NULL.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26 13:51:03 -04:00
Al Viro
25b229dff4 fsnotify(): switch to passing const struct qstr * for file_name
Note that in fnsotify_move() and fsnotify_link() we are guaranteed
that dentry->d_name won't change during the fsnotify() evaluation
(by having the parent directory locked exclusive), so we don't
need to fetch dentry->d_name.name in the callers.  In fsnotify_dirent()
the same stability of dentry->d_name is also true, but it's a bit
more convoluted - there is one callchain (devpts_pty_new() ->
fsnotify_create() -> fsnotify_dirent()) where the parent is _not_
locked, but on devpts ->d_name of everything is unchanging; it
has neither explicit nor implicit renames.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26 13:37:25 -04:00
Al Viro
230c6402b1 ovl_lookup_real_one(): don't bother with strlen()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-04-26 13:13:33 -04:00
David Howells
5dd50aaeb1
Make anon_inodes unconditional
Make the anon_inodes facility unconditional so that it can be used by core
VFS code and pidfd code.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[christian@brauner.io: adapt commit message to mention pidfds]
Signed-off-by: Christian Brauner <christian@brauner.io>
2019-04-19 14:03:11 +02:00
Jan Kara
b2d22b6bb3 fanotify: Allow copying of file handle to userspace
When file handle is embedded inside fanotify_event and usercopy checks
are enabled, we get a warning like:

Bad or missing usercopy whitelist? Kernel memory exposure attempt detected
from SLAB object 'fanotify_event' (offset 40, size 8)!
WARNING: CPU: 1 PID: 7649 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110
mm/usercopy.c:78

Annotate handling in fanotify_event properly to mark copying it to
userspace is fine.

Reported-by: syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com
Fixes: a8b13aa20a ("fanotify: enable FAN_REPORT_FID init flag")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-19 09:29:07 +01:00
ZhangXiaoxu
62c9d2674b inotify: Fix fsnotify_mark refcount leak in inotify_update_existing_watch()
Commit 4d97f7d53d ("inotify: Add flag IN_MASK_CREATE for
inotify_add_watch()") forgot to call fsnotify_put_mark() with
IN_MASK_CREATE after fsnotify_find_mark()

Fixes: 4d97f7d53d ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()")
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-11 10:13:17 +01:00
Jan Kara
b519057981 fanotify: Make waits for fanotify events only killable
Making waits for response to fanotify permission events interruptible
can result in EINTR returns from open(2) or other syscalls when there's
e.g. AV software that's monitoring the file. Orion reports that e.g.
bash is complaining like:

bash: /etc/bash_completion.d/itweb-settings.bash: Interrupted system call

So for now convert the wait from interruptible to only killable one.
That is mostly invisible to userspace. Sadly this breaks hibernation
with fanotify permission events pending again but we have to put more
thought into how to fix this without regressing userspace visible
behavior.

Reported-by: Orion Poplawski <orion@nwra.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-21 11:47:23 +01:00
Jan Kara
fabf7f29b3 fanotify: Use interruptible wait when waiting for permission events
When waiting for response to fanotify permission events, we currently
use uninterruptible waits. That makes code simple however it can cause
lots of processes to end up in uninterruptible sleep with hard reboot
being the only alternative in case fanotify listener process stops
responding (e.g. due to a bug in its implementation). Uninterruptible
sleep also makes system hibernation fail if the listener gets frozen
before the process generating fanotify permission event.

Fix these problems by using interruptible sleep for waiting for response
to fanotify event. This is slightly tricky though - we have to
detect when the event got already reported to userspace as in that
case we must not free the event. Instead we push the responsibility for
freeing the event to the process that will write response to the
event.

Reported-by: Orion Poplawski <orion@nwra.com>
Reported-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18 12:41:16 +01:00
Jan Kara
40873284d7 fanotify: Track permission event state
Track whether permission event got already reported to userspace and
whether userspace already answered to the permission event. Protect
stores to this field together with updates to ->response field by
group->notification_lock. This will allow aborting wait for reply to
permission event from userspace.

Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-02-18 12:41:16 +01:00