Commit ceaf69f8ea ("fanotify: do not allow setting dirent events in
mask of non-dir") added restrictions about setting dirent events in the
mask of a non-dir inode mark, which does not make any sense.
For backward compatibility, these restictions were added only to new
(v5.17+) APIs.
It also does not make any sense to set the flags FAN_EVENT_ON_CHILD or
FAN_ONDIR in the mask of a non-dir inode. Add these flags to the
dir-only restriction of the new APIs as well.
Move the check of the dir-only flags for new APIs into the helper
fanotify_events_supported(), which is only called for FAN_MARK_ADD,
because there is no need to error on an attempt to remove the dir-only
flags from non-dir inode.
Fixes: ceaf69f8ea ("fanotify: do not allow setting dirent events in mask of non-dir")
Link: https://lore.kernel.org/linux-fsdevel/20220627113224.kr2725conevh53u4@quack3.lan/
Link: https://lore.kernel.org/r/20220627174719.2838175-1-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
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Merge tag 'fsnotify_for_v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
"The biggest part of this is support for fsnotify inode marks that
don't pin inodes in memory but rather get evicted together with the
inode (they are useful if userspace needs to exclude receipt of events
from potentially large subtrees using fanotify ignore marks).
There is also a fix for more consistent handling of events sent to
parent and a fix of sparse(1) complaints"
* tag 'fsnotify_for_v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fanotify: fix incorrect fmode_t casts
fsnotify: consistent behavior for parent not watching children
fsnotify: introduce mark type iterator
fanotify: enable "evictable" inode marks
fanotify: use fsnotify group lock helpers
fanotify: implement "evictable" inode marks
fanotify: factor out helper fanotify_mark_update_flags()
fanotify: create helper fanotify_mark_user_flags()
fsnotify: allow adding an inode mark without pinning inode
dnotify: use fsnotify group lock helpers
nfsd: use fsnotify group lock helpers
audit: use fsnotify group lock helpers
inotify: use fsnotify group lock helpers
fsnotify: create helpers for group mark_mutex lock
fsnotify: make allow_dups a property of the group
fsnotify: pass flags argument to fsnotify_alloc_group()
fsnotify: fix wrong lockdep annotations
inotify: move control flags from mask to mark flags
inotify: show inotify mask flags in proc fdinfo
Fixes sparce warnings:
fs/notify/fanotify/fanotify_user.c:267:63: sparse:
warning: restricted fmode_t degrades to integer
fs/notify/fanotify/fanotify_user.c:1351:28: sparse:
warning: restricted fmode_t degrades to integer
FMODE_NONTIFY have bitwise fmode_t type and requires __force attribute
for any casts.
Signed-off-by: Vasily Averin <vvs@openvz.org>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/9adfd6ac-1b89-791e-796b-49ada3293985@openvz.org
The logic for handling events on child in groups that have a mark on
the parent inode, but without FS_EVENT_ON_CHILD flag in the mask is
duplicated in several places and inconsistent.
Move the logic into the preparation of mark type iterator, so that the
parent mark type will be excluded from all mark type iterations in that
case.
This results in several subtle changes of behavior, hopefully all
desired changes of behavior, for example:
- Group A has a mount mark with FS_MODIFY in mask
- Group A has a mark with ignore mask that does not survive FS_MODIFY
and does not watch children on directory D.
- Group B has a mark with FS_MODIFY in mask that does watch children
on directory D.
- FS_MODIFY event on file D/foo should not clear the ignore mask of
group A, but before this change it does
And if group A ignore mask was set to survive FS_MODIFY:
- FS_MODIFY event on file D/foo should be reported to group A on account
of the mount mark, but before this change it is wrongly ignored
Fixes: 2f02fd3fa1 ("fanotify: fix ignore mask logic for events on child and on dir")
Reported-by: Jan Kara <jack@suse.com>
Link: https://lore.kernel.org/linux-fsdevel/20220314113337.j7slrb5srxukztje@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220511190213.831646-3-amir73il@gmail.com
fsnotify_foreach_iter_mark_type() is used to reduce boilerplate code
of iterating all marks of a specific group interested in an event
by consulting the iterator report_mask.
Use an open coded version of that iterator in fsnotify_iter_next()
that collects all marks of the current iteration group without
consulting the iterator report_mask.
At the moment, the two iterator variants are the same, but this
decoupling will allow us to exclude some of the group's marks from
reporting the event, for example for event on child and inode marks
on parent did not request to watch events on children.
Fixes: 2f02fd3fa1 ("fanotify: fix ignore mask logic for events on child and on dir")
Reported-by: Jan Kara <jack@suse.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220511190213.831646-2-amir73il@gmail.com
Dirent events (create/delete/move) are only reported on watched
directory inodes, but in fanotify as well as in legacy inotify, it was
always allowed to set them on non-dir inode, which does not result in
any meaningful outcome.
Until kernel v5.17, dirent events in fanotify also differed from events
"on child" (e.g. FAN_OPEN) in the information provided in the event.
For example, FAN_OPEN could be set in the mask of a non-dir or the mask
of its parent and event would report the fid of the child regardless of
the marked object.
By contrast, FAN_DELETE is not reported if the child is marked and the
child fid was not reported in the events.
Since kernel v5.17, with fanotify group flag FAN_REPORT_TARGET_FID, the
fid of the child is reported with dirent events, like events "on child",
which may create confusion for users expecting the same behavior as
events "on child" when setting events in the mask on a child.
The desired semantics of setting dirent events in the mask of a child
are not clear, so for now, deny this action for a group initialized
with flag FAN_REPORT_TARGET_FID and for the new event FAN_RENAME.
We may relax this restriction in the future if we decide on the
semantics and implement them.
Fixes: d61fd650e9 ("fanotify: introduce group flag FAN_REPORT_TARGET_FID")
Fixes: 8cc3b1ccd9 ("fanotify: wire up FAN_RENAME event")
Link: https://lore.kernel.org/linux-fsdevel/20220505133057.zm5t6vumc4xdcnsg@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220507080028.219826-1-amir73il@gmail.com
Direct reclaim from fanotify mark allocation context may try to evict
inodes with evictable marks of the same group and hit this deadlock:
[<0>] fsnotify_destroy_mark+0x1f/0x3a
[<0>] fsnotify_destroy_marks+0x71/0xd9
[<0>] __destroy_inode+0x24/0x7e
[<0>] destroy_inode+0x2c/0x67
[<0>] dispose_list+0x49/0x68
[<0>] prune_icache_sb+0x5b/0x79
[<0>] super_cache_scan+0x11c/0x16f
[<0>] shrink_slab.constprop.0+0x23e/0x40f
[<0>] shrink_node+0x218/0x3e7
[<0>] do_try_to_free_pages+0x12a/0x2d2
[<0>] try_to_free_pages+0x166/0x242
[<0>] __alloc_pages_slowpath.constprop.0+0x30c/0x903
[<0>] __alloc_pages+0xeb/0x1c7
[<0>] cache_grow_begin+0x6f/0x31e
[<0>] fallback_alloc+0xe0/0x12d
[<0>] ____cache_alloc_node+0x15a/0x17e
[<0>] kmem_cache_alloc_trace+0xa1/0x143
[<0>] fanotify_add_mark+0xd5/0x2b2
[<0>] do_fanotify_mark+0x566/0x5eb
[<0>] __x64_sys_fanotify_mark+0x21/0x24
[<0>] do_syscall_64+0x6d/0x80
[<0>] entry_SYSCALL_64_after_hwframe+0x44/0xae
Set the FSNOTIFY_GROUP_NOFS flag to prevent going into direct reclaim
from allocations under fanotify group lock and use the safe group lock
helpers.
Link: https://lore.kernel.org/r/20220422120327.3459282-16-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
When an inode mark is created with flag FAN_MARK_EVICTABLE, it will not
pin the marked inode to inode cache, so when inode is evicted from cache
due to memory pressure, the mark will be lost.
When an inode mark with flag FAN_MARK_EVICATBLE is updated without using
this flag, the marked inode is pinned to inode cache.
When an inode mark is updated with flag FAN_MARK_EVICTABLE but an
existing mark already has the inode pinned, the mark update fails with
error EEXIST.
Evictable inode marks can be used to setup inode marks with ignored mask
to suppress events from uninteresting files or directories in a lazy
manner, upon receiving the first event, without having to iterate all
the uninteresting files or directories before hand.
The evictbale inode mark feature allows performing this lazy marks setup
without exhausting the system memory with pinned inodes.
This change does not enable the feature yet.
Link: https://lore.kernel.org/linux-fsdevel/CAOQ4uxiRDpuS=2uA6+ZUM7yG9vVU-u212tkunBmSnP_u=mkv=Q@mail.gmail.com/
Link: https://lore.kernel.org/r/20220422120327.3459282-15-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Handle FAN_MARK_IGNORED_SURV_MODIFY flag change in a helper that
is called after updating the mark mask.
Replace the added and removed return values and help variables with
bool recalc return values and help variable, which makes the code a
bit easier to follow.
Rename flags argument to fan_flags to emphasize the difference from
mark->flags.
Link: https://lore.kernel.org/r/20220422120327.3459282-14-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fsnotify_add_mark() and variants implicitly take a reference on inode
when attaching a mark to an inode.
Make that behavior opt-out with the mark flag FSNOTIFY_MARK_FLAG_NO_IREF.
Instead of taking the inode reference when attaching connector to inode
and dropping the inode reference when detaching connector from inode,
take the inode reference on attach of the first mark that wants to hold
an inode reference and drop the inode reference on detach of the last
mark that wants to hold an inode reference.
Backends can "upgrade" an existing mark to take an inode reference, but
cannot "downgrade" a mark with inode reference to release the refernce.
This leaves the choice to the backend whether or not to pin the inode
when adding an inode mark.
This is intended to be used when adding a mark with ignored mask that is
used for optimization in cases where group can afford getting unneeded
events and reinstate the mark with ignored mask when inode is accessed
again after being evicted.
Link: https://lore.kernel.org/r/20220422120327.3459282-12-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Before commit 9542e6a643 ("nfsd: Containerise filecache laundrette")
nfsd would close open files in direct reclaim context. There is no
guarantee that others memory shrinkers don't do the same and no
guarantee that future shrinkers won't do that.
For example, if overlayfs implements inode cache of fscache would
keep open files to cached objects, inode shrinkers could end up closing
open files to underlying fs.
Direct reclaim from dnotify mark allocation context may try to close
open files that have dnotify marks of the same group and hit a deadlock
on mark_mutex.
Set the FSNOTIFY_GROUP_NOFS flag to prevent going into direct reclaim
from allocations under dnotify group lock and use the safe group lock
helpers.
Link: https://lore.kernel.org/r/20220422120327.3459282-11-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Create helpers to take and release the group mark_mutex lock.
Define a flag FSNOTIFY_GROUP_NOFS in fsnotify_group that determines
if the mark_mutex lock is fs reclaim safe or not. If not safe, the
lock helpers take the lock and disable direct fs reclaim.
In that case we annotate the mutex with a different lockdep class to
express to lockdep that an allocation of mark of an fs reclaim safe group
may take the group lock of another "NOFS" group to evict inodes.
For now, converted only the callers in common code and no backend
defines the NOFS flag. It is intended to be set by fanotify for
evictable marks support.
Link: https://lore.kernel.org/r/20220422120327.3459282-7-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Instead of passing the allow_dups argument to fsnotify_add_mark()
as an argument, define the group flag FSNOTIFY_GROUP_DUPS to express
the allow_dups behavior and set this behavior at group creation time
for all calls of fsnotify_add_mark().
Rename the allow_dups argument to generic add_flags argument for future
use.
Link: https://lore.kernel.org/r/20220422120327.3459282-6-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>
Add flags argument to fsnotify_alloc_group(), define and use the flag
FSNOTIFY_GROUP_USER in inotify and fanotify instead of the helper
fsnotify_alloc_user_group() to indicate user allocation.
Although the flag FSNOTIFY_GROUP_USER is currently not used after group
allocation, we store the flags argument in the group struct for future
use of other group flags.
Link: https://lore.kernel.org/r/20220422120327.3459282-5-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Commit 6960b0d909 ("fsnotify: change locking order") changed some
of the mark_mutex locks in direct reclaim path to use:
mutex_lock_nested(&group->mark_mutex, SINGLE_DEPTH_NESTING);
This change is explained:
"...It uses nested locking to avoid deadlock in case we do the final
iput() on an inode which still holds marks and thus would take the
mutex again when calling fsnotify_inode_delete() in destroy_inode()."
The problem is that the mutex_lock_nested() is not a nested lock at
all. In fact, it has the opposite effect of preventing lockdep from
warning about a very possible deadlock.
Due to these wrong annotations, a deadlock that was introduced with
nfsd filecache in kernel v5.4 went unnoticed in v5.4.y for over two
years until it was reported recently by Khazhismel Kumykov, only to
find out that the deadlock was already fixed in kernel v5.5.
Fix the wrong lockdep annotations.
Cc: Khazhismel Kumykov <khazhy@google.com>
Fixes: 6960b0d909 ("fsnotify: change locking order")
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Link: https://lore.kernel.org/r/20220422120327.3459282-4-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The inotify control flags in the mark mask (e.g. FS_IN_ONE_SHOT) are not
relevant to object interest mask, so move them to the mark flags.
This frees up some bits in the object interest mask.
Link: https://lore.kernel.org/r/20220422120327.3459282-3-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The inotify mask flags IN_ONESHOT and IN_EXCL_UNLINK are not "internal
to kernel" and should be exposed in procfs fdinfo so CRIU can restore
them.
Fixes: 6933599697 ("inotify: hide internal kernel bits from fdinfo")
Link: https://lore.kernel.org/r/20220422120327.3459282-2-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fsnotify() treats FS_MODIFY events specially - it does not skip them
even if the FS_MODIFY event does not apear in the object's fsnotify
mask. This is because send_to_group() checks if FS_MODIFY needs to
clear ignored mask of marks.
The common case is that an object does not have any mark with ignored
mask and in particular, that it does not have a mark with ignored mask
and without the FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY flag.
Set FS_MODIFY in object's fsnotify mask during fsnotify_recalc_mask()
if object has a mark with an ignored mask and without the
FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY flag and remove the special
treatment of FS_MODIFY in fsnotify(), so that FS_MODIFY events could
be optimized in the common case.
Call fsnotify_recalc_mask() from fanotify after adding or removing an
ignored mask from a mark without FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY
or when adding the FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY flag to a mark
with ignored mask (the flag cannot be removed by fanotify uapi).
Performance results for doing 10000000 write(2)s to tmpfs:
vanilla patched
without notification mark 25.486+-1.054 24.965+-0.244
with notification mark 30.111+-0.139 26.891+-1.355
So we can see the overhead of notification subsystem has been
drastically reduced.
Link: https://lore.kernel.org/r/20220223151438.790268-3-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>
fsnotify_parent() does not consider the parent's mark at all unless
the parent inode shows interest in events on children and in the
specific event.
So unless parent added an event to both its mark mask and ignored mask,
the event will not be ignored.
Fix this by declaring the interest of an object in an event when the
event is in either a mark mask or ignored mask.
Link: https://lore.kernel.org/r/20220223151438.790268-2-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This code calls fd_install() which gives the userspace access to the fd.
Then if copy_info_records_to_user() fails it calls put_unused_fd(fd) but
that will not release it and leads to a stale entry in the file
descriptor table.
Generally you can't trust the fd after a call to fd_install(). The fix
is to delay the fd_install() until everything else has succeeded.
Fortunately it requires CAP_SYS_ADMIN to reach this code so the security
impact is less.
Fixes: f644bc449b ("fanotify: fix copy_event_to_user() fid error clean up")
Link: https://lore.kernel.org/r/20220128195656.GA26981@kili
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Mathias Krause <minipli@grsecurity.net>
Signed-off-by: Jan Kara <jack@suse.cz>
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Merge tag 'fsnotify_for_v5.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify fixes from Jan Kara:
"Fixes for userspace breakage caused by fsnotify changes ~3 years ago
and one fanotify cleanup"
* tag 'fsnotify_for_v5.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: fix fsnotify hooks in pseudo filesystems
fsnotify: invalidate dcache before IN_DELETE event
fanotify: remove variable set but not used
There is no need to user boiler plate code to specify a set of base
directories we're going to stuff sysctls under. Simplify this by using
register_sysctl() and specifying the directory path directly.
Move inotify_user sysctl to inotify_user.c while at it to remove clutter
from kernel/sysctl.c.
[mcgrof@kernel.org: remember to register fanotify_table]
Link: https://lkml.kernel.org/r/YZ5A6iWLb0h3N3RC@bombadil.infradead.org
[mcgrof@kernel.org: update commit log to reflect new path we decided to take]
Link: https://lkml.kernel.org/r/20211123202422.819032-7-mcgrof@kernel.org
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: David Airlie <airlied@linux.ie>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Qing Wang <wangqing@vivo.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.
To help with this maintenance let's start by moving sysctls to places
where they actually belong. The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.
So move dnotify sysctls to dnotify.c and use the new
register_sysctl_init() to register the sysctl interface.
[mcgrof@kernel.org: adjust the commit log to justify the move]
Link: https://lkml.kernel.org/r/20211123202347.818157-10-mcgrof@kernel.org
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Qing Wang <wangqing@vivo.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code that uses the pointer info has been removed in 7326e382c2
("fanotify: report old and/or new parent+name in FAN_RENAME event").
and fanotify_event_info() doesn't change 'event', so the declaration and
assignment of info can be removed.
Eliminate the following clang warning:
fs/notify/fanotify/fanotify_user.c:161:24: warning: variable ‘info’ set
but not used
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Jan Kara <jack@suse.cz>
FAN_RENAME is the successor of FAN_MOVED_FROM and FAN_MOVED_TO
and can be used to get the old and new parent+name information in
a single event.
FAN_MOVED_FROM and FAN_MOVED_TO are still supported for backward
compatibility, but it makes little sense to use them together with
FAN_RENAME in the same group.
FAN_RENAME uses special info type records to report the old and
new parent+name, so reporting only old and new parent id is less
useful and was not implemented.
Therefore, FAN_REANAME requires a group with flag FAN_REPORT_NAME.
Link: https://lore.kernel.org/r/20211129201537.1932819-12-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
In the special case of FAN_RENAME event, we report old or new or both
old and new parent+name.
A single info record will be reported if either the old or new dir
is watched and two records will be reported if both old and new dir
(or their filesystem) are watched.
The old and new parent+name are reported using new info record types
FAN_EVENT_INFO_TYPE_{OLD,NEW}_DFID_NAME, so if a single info record
is reported, it is clear to the application, to which dir entry the
fid+name info is referring to.
Link: https://lore.kernel.org/r/20211129201537.1932819-11-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
We do not want to report the dirfid+name of a directory whose
inode/sb are not watched, because watcher may not have permissions
to see the directory content.
Use an internal iter_info to indicate to fanotify_alloc_event()
which marks of this group are watching FAN_RENAME, so it can decide
if we need to record only the old parent+name, new parent+name or both.
Link: https://lore.kernel.org/r/20211129201537.1932819-10-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
[JK: Modified code to pass around only mask of mark types matching
generated event]
Signed-off-by: Jan Kara <jack@suse.cz>
Allow storing a secondary dir fh and name tupple in fanotify_info.
This will be used to store the new parent and name information in
FAN_RENAME event.
Link: https://lore.kernel.org/r/20211129201537.1932819-8-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fanotify_info buffer is parceled into variable sized records, so the
records must be written in order: dir_fh, file_fh, name.
Use helpers to assert that order and make fanotify_alloc_name_event()
a bit more generic to allow empty dir_fh record and to allow expanding
to more records (i.e. name2) soon.
Link: https://lore.kernel.org/r/20211129201537.1932819-7-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The fanotify_info buffer contains up to two file handles and a name.
Use macros to simplify the code that access the different items within
the buffer.
Add assertions to verify that stored fh len and name len do not overflow
the u8 stored value in fanotify_info header.
Remove the unused fanotify_info_len() helper.
Link: https://lore.kernel.org/r/20211129201537.1932819-6-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The dnotify FS_DN_RENAME event is used to request notification about
a move within the same parent directory and was always coupled with
the FS_MOVED_FROM event.
Rename the FS_DN_RENAME event flag to FS_RENAME, decouple it from
FS_MOVED_FROM and report it with the moved dentry instead of the moved
inode, so it has the information about both old and new parent and name.
Generate the FS_RENAME event regardless of same parent dir and apply
the "same parent" rule in the generic fsnotify_handle_event() helper
that is used to call backends with ->handle_inode_event() method
(i.e. dnotify). The ->handle_inode_event() method is not rich enough to
report both old and new parent and name anyway.
The enriched event is reported to fanotify over the ->handle_event()
method with the old and new dir inode marks in marks array slots for
ITER_TYPE_INODE and a new iter type slot ITER_TYPE_INODE2.
The enriched event will be used for reporting old and new parent+name to
fanotify groups with FAN_RENAME events.
Link: https://lore.kernel.org/r/20211129201537.1932819-5-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
FAN_REPORT_FID is ambiguous in that it reports the fid of the child for
some events and the fid of the parent for create/delete/move events.
The new FAN_REPORT_TARGET_FID flag is an implicit request to report
the fid of the target object of the operation (a.k.a the child inode)
also in create/delete/move events in addition to the fid of the parent
and the name of the child.
To reduce the test matrix for uninteresting use cases, the new
FAN_REPORT_TARGET_FID flag requires both FAN_REPORT_NAME and
FAN_REPORT_FID. The convenience macro FAN_REPORT_DFID_NAME_TARGET
combines FAN_REPORT_TARGET_FID with all the required flags.
Link: https://lore.kernel.org/r/20211129201537.1932819-4-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
They are two different types that use the same enum, so this confusing.
Use the object type to indicate the type of object mark is attached to
and the iter type to indicate the type of watch.
A group can have two different watches of the same object type (parent
and child watches) that match the same event.
Link: https://lore.kernel.org/r/20211129201537.1932819-3-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
In preparation for separating object type from iterator type, rename
some 'type' arguments in functions to 'obj_type' and remove the unused
interface to clear marks by object type mask.
Link: https://lore.kernel.org/r/20211129201537.1932819-2-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Wire up the FAN_FS_ERROR event in the fanotify_mark syscall, allowing
user space to request the monitoring of FAN_FS_ERROR events.
These events are limited to filesystem marks, so check it is the
case in the syscall handler.
Link: https://lore.kernel.org/r/20211025192746.66445-29-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The error info is a record sent to users on FAN_FS_ERROR events
documenting the type of error. It also carries an error count,
documenting how many errors were observed since the last reporting.
Link: https://lore.kernel.org/r/20211025192746.66445-28-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Plumb the pieces to add a FID report to error records. Since all error
event memory must be pre-allocated, we pre-allocate the maximum file
handle size possible, such that it should always fit.
For errors that don't expose a file handle, report it with an invalid
FID. Internally we use zero-length FILEID_ROOT file handle for passing
the information (which we report as zero-length FILEID_INVALID file
handle to userspace) so we update the handle reporting code to deal with
this case correctly.
Link: https://lore.kernel.org/r/20211025192746.66445-27-krisman@collabora.com
Link: https://lore.kernel.org/r/20211025192746.66445-25-krisman@collabora.com
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
[Folded two patches into 2 to make series bisectable]
Signed-off-by: Jan Kara <jack@suse.cz>
struct fanotify_error_event, at least, is preallocated and isn't able to
to handle arbitrarily large file handles. Future-proof the code by
complaining loudly if a handle larger than MAX_HANDLE_SZ is ever found.
Link: https://lore.kernel.org/r/20211025192746.66445-26-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Now that there is an event that reports FID records even for a zeroed
file handle, wrap the logic that deides whether to issue the records
into helper functions. This shouldn't have any impact on the code, but
simplifies further patches.
Link: https://lore.kernel.org/r/20211025192746.66445-24-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
fanotify_error_event would duplicate this sequence of declarations that
already exist elsewhere with a slight different size. Create a helper
macro to avoid code duplication.
Link: https://lore.kernel.org/r/20211025192746.66445-23-krisman@collabora.com
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Error events (FAN_FS_ERROR) against the same file system can be merged
by simply iterating the error count. The hash is taken from the fsid,
without considering the FH. This means that only the first error object
is reported.
Link: https://lore.kernel.org/r/20211025192746.66445-22-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Once an error event is triggered, enqueue it in the notification group,
similarly to what is done for other events. FAN_FS_ERROR is not
handled specially, since the memory is now handled by a preallocated
mempool.
For now, make the event unhashed. A future patch implements merging of
this kind of event.
Link: https://lore.kernel.org/r/20211025192746.66445-21-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Pre-allocate slots for file system errors to have greater chances of
succeeding, since error events can happen in GFP_NOFS context. This
patch introduces a group-wide mempool of error events, shared by all
FAN_FS_ERROR marks in this group.
Link: https://lore.kernel.org/r/20211025192746.66445-20-krisman@collabora.com
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
FAN_FS_ERROR allows reporting of event type FS_ERROR to userspace, which
is a mechanism to report file system wide problems via fanotify. This
commit preallocate userspace visible bits to match the FS_ERROR event.
Link: https://lore.kernel.org/r/20211025192746.66445-19-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Like inode events, FAN_FS_ERROR will require fid mode. Therefore,
convert the verification during fanotify_mark(2) to require fid for any
non-fd event. This means fid_mode will not only be required for inode
events, but for any event that doesn't provide a descriptor.
Link: https://lore.kernel.org/r/20211025192746.66445-17-krisman@collabora.com
Suggested-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
