25 Feb, 2018
1 commit
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commit b3a0066005821acdc0cdb092cb72587182ab583f upstream.
fsnotify_add_mark_locked() can fail but we do not check its return
value. This didn't matter before commit 9dd813c15b2c "fsnotify: Move
mark list head from object into dedicated structure" as none of possible
failures could happen for dnotify but after that commit -ENOMEM can be
returned. Handle this error properly in fcntl_dirnotify() as
otherwise we just hit BUG_ON(dn_mark->dn) in dnotify_free_mark().Reviewed-by: Amir Goldstein
Reported-by: syzkaller
Fixes: 9dd813c15b2c101168808d4f5941a29985758973
Signed-off-by: Jan Kara
Signed-off-by: Greg Kroah-Hartman
30 Aug, 2017
1 commit
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Make this const as it is never modified.
Signed-off-by: Bhumika Goyal
Signed-off-by: Jan Kara
10 Apr, 2017
7 commits
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Pointer to ->free_mark callback unnecessarily occupies one long in each
fsnotify_mark although they are the same for all marks from one
notification group. Move the callback pointer to fsnotify_ops.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
Currently we initialize mark->group only in fsnotify_add_mark_lock().
However we will need to access fsnotify_ops of corresponding group from
fsnotify_put_mark() so we need mark->group initialized earlier. Do that
in fsnotify_init_mark() which has a consequence that once
fsnotify_init_mark() is called on a mark, the mark has to be destroyed
by fsnotify_put_mark().Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
These are very thin wrappers, just remove them. Drop
fs/notify/vfsmount_mark.c as it is empty now.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
These helpers are now only a simple assignment and just obfuscate
what is going on. Remove them.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
Pass fsnotify_iter_info into ->handle_event() handler so that it can
release and reacquire SRCU lock via fsnotify_prepare_user_wait() and
fsnotify_finish_user_wait() functions. These functions also make sure
current marks are appropriately pinned so that iteration protected by
srcu in fsnotify() stays safe.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
Move locking of locks protecting a list of marks into
fsnotify_recalc_mask(). This reduces code churn in the following patch
which changes the lock protecting the list of marks.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara -
Move pointer to inode / vfsmount from mark itself to the
fsnotify_mark_connector structure. This is another step on the path
towards decoupling inode / vfsmount lifetime from notification mark
lifetime.Reviewed-by: Miklos Szeredi
Reviewed-by: Amir Goldstein
Signed-off-by: Jan Kara
06 Dec, 2016
1 commit
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Signed-off-by: Al Viro
05 Sep, 2015
1 commit
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fsnotify_destroy_mark_locked() is subtle to use because it temporarily
releases group->mark_mutex. To avoid future problems with this
function, split it into two.fsnotify_detach_mark() is the part that needs group->mark_mutex and
fsnotify_free_mark() is the part that must be called outside of
group->mark_mutex. This way it's much clearer what's going on and we
also avoid some pointless acquisitions of group->mark_mutex.Signed-off-by: Jan Kara
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
14 Dec, 2014
1 commit
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There's a lot of common code in inode and mount marks handling. Factor it
out to a common helper function.Signed-off-by: Jan Kara
Cc: Eric Paris
Cc: Heinrich Schuchardt
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Sep, 2014
1 commit
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security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton
Reviewed-by: Christoph Hellwig
18 Feb, 2014
1 commit
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My rework of handling of notification events (namely commit 7053aee26a35
"fsnotify: do not share events between notification groups") broke
sending of cookies with inotify events. We didn't propagate the value
passed to fsnotify() properly and passed 4 uninitialized bytes to
userspace instead (so it is also an information leak). Sadly I didn't
notice this during my testing because inotify cookies aren't used very
much and LTP inotify tests ignore them.Fix the problem by passing the cookie value properly.
Fixes: 7053aee26a3548ebaba046ae2e52396ccf56ac6c
Reported-by: Vegard Nossum
Signed-off-by: Jan Kara
22 Jan, 2014
3 commits
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We usually rely on the fact that struct members not specified in the
initializer are set to NULL. So do that with fsnotify function pointers
as well.Signed-off-by: Jan Kara
Reviewed-by: Christoph Hellwig
Cc: Eric Paris
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
After removing event structure creation from the generic layer there is
no reason for separate .should_send_event and .handle_event callbacks.
So just remove the first one.Signed-off-by: Jan Kara
Reviewed-by: Christoph Hellwig
Cc: Eric Paris
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently fsnotify framework creates one event structure for each
notification event and links this event into all interested notification
groups. This is done so that we save memory when several notification
groups are interested in the event. However the need for event
structure shared between inotify & fanotify bloats the event structure
so the result is often higher memory consumption.Another problem is that fsnotify framework keeps path references with
outstanding events so that fanotify can return open file descriptors
with its events. This has the undesirable effect that filesystem cannot
be unmounted while there are outstanding events - a regression for
inotify compared to a situation before it was converted to fsnotify
framework. For fanotify this problem is hard to avoid and users of
fanotify should kind of expect this behavior when they ask for file
descriptors from notified files.This patch changes fsnotify and its users to create separate event
structure for each group. This allows for much simpler code (~400 lines
removed by this patch) and also smaller event structures. For example
on 64-bit system original struct fsnotify_event consumes 120 bytes, plus
additional space for file name, additional 24 bytes for second and each
subsequent group linking the event, and additional 32 bytes for each
inotify group for private data. After the conversion inotify event
consumes 48 bytes plus space for file name which is considerably less
memory unless file names are long and there are several groups
interested in the events (both of which are uncommon). Fanotify event
fits in 56 bytes after the conversion (fanotify doesn't care about file
names so its events don't have to have it allocated). A win unless
there are four or more fanotify groups interested in the event.The conversion also solves the problem with unmount when only inotify is
used as we don't have to grab path references for inotify events.[hughd@google.com: fanotify: fix corruption preventing startup]
Signed-off-by: Jan Kara
Reviewed-by: Christoph Hellwig
Cc: Eric Paris
Cc: Al Viro
Signed-off-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Jul, 2013
1 commit
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There is no need to use a special mutex to protect against the
fcntl/close race (see dnotify.c for a description of this race).
Instead the dnotify_groups mark mutex can be used.Signed-off-by: Lino Sanfilippo
Cc: Eric Paris
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
23 Feb, 2013
1 commit
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Signed-off-by: Al Viro
12 Dec, 2012
1 commit
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In fsnotify_destroy_mark() dont get the group from the passed mark anymore,
but pass the group itself as an additional parameter to the function.Signed-off-by: Lino Sanfilippo
Signed-off-by: Eric Paris
28 Jul, 2010
20 commits
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fanotify currently, when given a vfsmount_mark will look up (if it exists)
the corresponding inode mark. This patch drops that lookup and uses the
mark provided.Signed-off-by: Eric Paris
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should_send_event() and handle_event() will both need to look up the inode
event if they get a vfsmount event. Lets just pass both at the same time
since we have them both after walking the lists in lockstep.Signed-off-by: Eric Paris
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group->mask is now useless. It was originally a shortcut for fsnotify to
save on performance. These checks are now redundant, so we remove them.Signed-off-by: Eric Paris
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The change to use srcu and walk the object list rather than the global
fsnotify_group list means that should_send_event is no longer needed for a
number of groups and can be simplified for others. Do that.Signed-off-by: Eric Paris
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dnotify now gets a mark in the should_send_event and handle_event
functions. Rather than look up the mark themselves dnotify should just use
the mark it was handed.Signed-off-by: Eric Paris
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With the change of fsnotify to use srcu walking the marks list instead of
walking the global groups list we now know the mark in question. The code can
send the mark to the group's handling functions and the groups won't have to
find those marks themselves.Signed-off-by: Eric Paris
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inotify marks must pin inodes in core. dnotify doesn't technically need to
since they are closed when the directory is closed. fanotify also need to
pin inodes in core as it works today. But the next step is to introduce
the concept of 'ignored masks' which is actually a mask of events for an
inode of no interest. I claim that these should be liberally sent to the
kernel and should not pin the inode in core. If the inode is brought back
in the listener will get an event it may have thought excluded, but this is
not a serious situation and one any listener should deal with.This patch lays the ground work for non-pinning inode marks by using lazy
inode pinning. We do not pin a mark until it has a non-zero mask entry. If a
listener new sets a mask we never pin the inode.Signed-off-by: Eric Paris
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currently all marking is done by functions in inode-mark.c. Some of this
is pretty generic and should be instead done in a generic function and we
should only put the inode specific code in inode-mark.cSigned-off-by: Eric Paris
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All callers to fsnotify_find_mark_entry() except one take and
release inode->i_lock around the call. Take the lock inside
fsnotify_find_mark_entry() instead.Signed-off-by: Andreas Gruenbacher
Signed-off-by: Eric Paris -
nomenclature change. Used to call things 'entries' but now we just call
them 'marks.' Do those changes for dnotify.Signed-off-by: Eric Paris
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the _entry portion of fsnotify functions is useless. Drop it.
Signed-off-by: Eric Paris
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The name is long and it serves no real purpose. So rename
fsnotify_mark_entry to just fsnotify_mark.Signed-off-by: Eric Paris
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The addition of marks on vfs mounts will be simplified if the inode
specific parts of a mark and the vfsmnt specific parts of a mark are
actually in a union so naming can be easy. This patch just implements the
inode struct and the union.Signed-off-by: Eric Paris
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To ensure that a group will not duplicate events when it receives it based
on the vfsmount and the inode should_send_event test we should distinguish
those two cases. We pass a vfsmount to this function so groups can make
their own determinations.Signed-off-by: Eric Paris
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Nothing uses the mask argument to fsnotify_alloc_group. This patch drops
that argument.Signed-off-by: Eric Paris
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fsnotify_obtain_group was intended to be able to find an already existing
group. Nothing uses that functionality. This just renames it to
fsnotify_alloc_group so it is clear what it is doing.Signed-off-by: Eric Paris
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The original fsnotify interface has a group-num which was intended to be
able to find a group after it was added. I no longer think this is a
necessary thing to do and so we remove the group_num.Signed-off-by: Eric Paris
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fanotify is going to need to look at file->private_data to know if an event
should be sent or not. This passes the data (which might be a file,
dentry, inode, or none) to the should_send function calls so fanotify can
get that information when availableSigned-off-by: Eric Paris
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fanotify is only interested in event types which contain enough information
to open the original file in the context of the fanotify listener. Since
fanotify may not want to send events if that data isn't present we pass
the data type to the should_send_event function call so fanotify can express
its lack of interest.Signed-off-by: Eric Paris
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This patch allows a task to add a second fsnotify mark to an inode for the
same group. This mark will be added to the end of the inode's list and
this will never be found by the stand fsnotify_find_mark() function. This
is useful if a user wants to add a new mark before removing the old one.Signed-off-by: Eric Paris
