This reverts commit b7dc2df572.
The initial patch didn't quite work since it doesn't cover all
the possible routes by which the GLF_FROZEN flag might be set.
A revised fix is coming up in the next patch.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This looks like a big change, but in reality its only a single line of actual
code change, the rest is just moving a function to before its new caller.
The "try" flag for glocks is a rather subtle and delicate setting since it
requires that the state machine tries just hard enough to ensure that it has
a good chance of getting the requested lock, but no so hard that the
request can land up blocked behind another.
The patch adds in an additional check which will fail any queued try
locks if there is another request blocking the try lock request which
is not granted and compatible, nor in progress already. The check is made
only after all pending locks which may be granted have been granted.
I've checked this with the reproducer for the reported flock bug which
this is intended to fix, and it now passes.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The k[mc]allocs in dr_split_leaf() and dir_double_exhash() are failable,
so remove __GFP_NOFAIL from their masks.
Cc: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Function gfs2_write_alloc_required always returned zero as its
return code. Therefore, it doesn't need to return a return code
at all. Given that, we can use the return value to return whether
or not the dinode needs block allocations rather than passing
that value in, which in turn simplifies a bunch of error checking.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch implements a wait for the journal id in the case that it has
not been specified on the command line. This is to allow the future
removal of the mount.gfs2 helper. The journal id would instead be
directly communicated by gfs_controld to the file system. Here is a
comparison of the two systems:
Current:
1. mount calls mount.gfs2
2. mount.gfs2 connects to gfs_controld to retrieve the journal id
3. mount.gfs2 adds the journal id to the mount command line and calls
the mount system call
4. gfs_controld receives the status of the mount request via a uevent
Proposed:
1. mount calls the mount system call (no mount.gfs2 helper)
2. gfs_controld receives a uevent for a gfs2 fs which it doesn't know
about already
3. gfs_controld assigns a journal id to it via sysfs
4. the mount system call then completes as normal (sending a uevent
according to status)
The advantage of the proposed system is that it is completely backward
compatible with the current system both at the kernel and at the
userland levels. The "first" parameter can also be set the same way,
with the restriction that it must be set before the journal id is
assigned.
In addition, if mount becomes stuck waiting for a reply from
gfs_controld which never arrives, then it is killable and will abort the
mount gracefully.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Use nobh_writepage rather than calling mpage_writepage directly.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
The function ecryptfs_uid_hash wrongly assumes that the
second parameter to hash_long() is the number of hash
buckets instead of the number of hash bits.
This patch fixes that and renames the variable
ecryptfs_hash_buckets to ecryptfs_hash_bits to make it
clearer.
Fixes: CVE-2010-2492
Signed-off-by: Andre Osterhues <aosterhues@escrypt.com>
Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If we don't need a huge amount of memory in ->readdir() then
we can use kmalloc rather than vmalloc to allocate it. This
should cut down on the greater overheads associated with
vmalloc for smaller directories.
We may be able to eliminate vmalloc entirely at some stage,
but this is easy to do right away.
Also using GFP_NOFS to avoid any issues wrt to deleting inodes
while under a glock, and suggestion from Linus to factor out
the alloc/dealloc.
I've given this a test with a variety of different sized
directories and it seems to work ok.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <eparis@redhat.com>
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 <eparis@redhat.com>
We currently walk the list of marks on an inode followed by the list of
marks on the vfsmount. These are in order (by the memory address of the
group) so lets walk them both together. Eventually we can pass both the
inode mark and the vfsmount mark to helpers simultaneously.
Signed-off-by: Eric Paris <eparis@redhat.com>
currently ignored_mark clearing is done in a seperate list traversal
before the actual list traversal to send events. There is no need for
this. Do them at the same time.
Signed-off-by: Eric Paris <eparis@redhat.com>
The global fsnotify groups lists were invented as a way to increase the
performance of fsnotify by shortcutting events which were not interesting.
With the changes to walk the object lists rather than global groups lists
these shortcuts are not useful.
Signed-off-by: Eric Paris <eparis@redhat.com>
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 <eparis@redhat.com>
Because we walk the object->fsnotify_marks list instead of the global
fsnotify groups list we don't need the fsnotify_inode_mask and
fsnotify_vfsmount_mask as these were simply shortcuts in fsnotify() for
performance. They are now extra checks, rip them out.
Signed-off-by: Eric Paris <eparis@redhat.com>
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 <eparis@redhat.com>
fanotify now gets a mark in the should_send_event and handle_event
functions. Rather than look up the mark themselves fanotify should just use
the mark it was handed.
Signed-off-by: Eric Paris <eparis@redhat.com>
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 <eparis@redhat.com>
inotify now gets a mark in the should_send_event and handle_event
functions. Rather than look up the mark themselves inotify should just use
the mark it was handed.
Signed-off-by: Eric Paris <eparis@redhat.com>
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 <eparis@redhat.com>
Instead of moving list elements from destroy_list to &private_destroy_list,
exchange the list heads.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
Currently reading the inode->i_fsnotify_marks or
vfsmount->mnt_fsnotify_marks lists are protected by a spinlock on both the
read and the write side. This patch protects the read side of those lists
with a new single srcu.
Signed-off-by: Eric Paris <eparis@redhat.com>
Currently fsnotify check is mark->group is NULL to decide if
fsnotify_destroy_mark() has already been called or not. With the upcoming
rcu work it is a heck of a lot easier to use an explicit flag than worry
about group being set to NULL.
Signed-off-by: Eric Paris <eparis@redhat.com>
In preparation for srcu locking use all _rcu appropiete functions for mark
list addition, removal, and traversal. The operations are still done under a
spinlock at the end of this patch.
Signed-off-by: Eric Paris <eparis@redhat.com>
fsnotify_marks currently are placed on objects (inodes or vfsmounts) in
arbitrary order. This patch places them in order of the group memory address.
Signed-off-by: Eric Paris <eparis@redhat.com>
fanotify almost works like so:
user context calls fsnotify_* function with a struct file.
fsnotify takes a reference on the struct path
user context goes about it's buissiness
at some later point in time the fsnotify listener gets the struct path
fanotify listener calls dentry_open() to create a file which userspace can deal with
listener drops the reference on the struct path
at some later point the listener calls close() on it's new file
With the switch from struct path to struct file this presents a problem for
fput() and fsnotify_close(). fsnotify_close() is called when the filp has
already reached 0 and __fput() wants to do it's cleanup.
The solution presented here is a bit odd. If an event is created from a
struct file we take a reference on the file. We check however if the f_count
was already 0 and if so we take an EXTRA reference EVEN THOUGH IT WAS ZERO.
In __fput() (where we know the f_count hit 0 once) we check if the f_count is
non-zero and if so we drop that 'extra' ref and return without destroying the
file.
Signed-off-by: Eric Paris <eparis@redhat.com>
Al explains that calling dentry_open() with a mnt/dentry pair is only
garunteed to be safe if they are already used in an open struct file. To
make sure this is the case don't store and use a struct path in fsnotify,
always use a struct file.
Signed-off-by: Eric Paris <eparis@redhat.com>
Rather than the horrific void ** argument and such just to pass the
fanotify_merge event back to the caller of fsnotify_add_notify_event() have
those things return an event if it was different than the event suggusted to
be added.
Signed-off-by: Eric Paris <eparis@redhat.com>
It can be hard to debug fsnotify since there are so few printks. Use
pr_debug to allow for dynamic debugging.
Signed-off-by: Eric Paris <eparis@redhat.com>
Currently fanotify fds opened for thier listeners are done with f_flags
equal to O_RDONLY | O_LARGEFILE. This patch instead takes f_flags from the
fanotify_init syscall and uses those when opening files in the context of
the listener.
Signed-off-by: Eric Paris <eparis@redhat.com>
This patch adds a check to make sure that all fsnotify bits are unique and we
cannot accidentally use the same bit for 2 different fsnotify event types.
Signed-off-by: Eric Paris <eparis@redhat.com>
The mask checks in inotify_update_existing_watch() and
inotify_new_watch() are useless because inotify_arg_to_mask() sets
FS_IN_IGNORED and FS_EVENT_ON_CHILD bits anyway.
Signed-off-by: Eric Paris <eparis@redhat.com>
inotify uses bits called IN_* and fsnotify uses bits called FS_*. These
need to line up. This patch adds build time checks to make sure noone can
change these bits so they are not the same.
Signed-off-by: Eric Paris <eparis@redhat.com>
An inotify watch on a directory will send events for children even if those
children have been unlinked. This patch add a new inotify flag IN_EXCL_UNLINK
which allows a watch to specificy they don't care about unlinked children.
This should fix performance problems seen by tasks which add a watch to
/tmp and then are overrun with events when other processes are reading and
writing to unlinked files they created in /tmp.
https://bugzilla.kernel.org/show_bug.cgi?id=16296
Requested-by: Matthias Clasen <mclasen@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Since the .31 or so notify rewrite inotify has not sent events about
inodes which are unmounted. This patch restores those events.
Signed-off-by: Eric Paris <eparis@redhat.com>
During the large inotify rewrite to fsnotify I completely dropped support
for IN_ONESHOT. Reimplement that support.
Signed-off-by: Eric Paris <eparis@redhat.com>
Implicit slab.h inclusion via percpu.h is about to go away. Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
fanotify has default to y in linux-next since it's inception but default to
n in the final push to Linus.
Signed-off-by: Eric Paris <eparis@redhat.com>
The symbol inotify_max_user_watches is not used outside this
file and should be static.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
fsnotify takes an igrab on an inode when it adds a mark. The code was
supposed to drop the reference when the mark was removed but didn't.
This caused problems when an fs was unmounted because those inodes would
clearly not be gone. Thus resulting in the most devistating of messages:
VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds.
>>> Have a nice day...
Jiri Slaby bisected the problem to a patch in the fsnotify tree. The
code snippets below show my stupidity quite clearly.
void fsnotify_destroy_inode_mark(struct fsnotify_mark *mark)
{
...
mark->inode = NULL;
...
}
void fsnotify_destroy_mark(struct fsnotify_mark *mark)
{
struct inode *inode = NULL;
...
if (mark->flags & FSNOTIFY_MARK_FLAG_INODE) {
fsnotify_destroy_inode_mark(mark);
inode = mark->i.inode;
}
...
if (inode)
iput(inode);
...
}
Obviously the intent was to capture the inode before it was set to NULL in
fsnotify_destory_inode_mark() so we wouldn't be leaking inodes forever.
Instead we leaked them (and exploded on umount)
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
It seems to me you are always returning 0 in fsnotify, when you should return
the error (EPERM) returned by fanotify.
Signed-off-by: Jean-Christophe DUBOIS <jcd@tribudubois.net>
Signed-off-by: Eric Paris <eparis@redhat.com>
remove_access_response() is supposed to have a void return, but was
returning 0;
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Eric Paris <eparis@redhat.com>
fanotify groups need to respond to events which include permissions types.
To do so groups will send a response using write() on the fanotify_fd they
have open.
Signed-off-by: Eric Paris <eparis@redhat.com>
This is the backend work needed for fanotify to support the new
FS_OPEN_PERM and FS_ACCESS_PERM fsnotify events. This is done using the
new fsnotify secondary queue. No userspace interface is provided actually
respond to or request these events.
Signed-off-by: Eric Paris <eparis@redhat.com>
introduce a new fsnotify hook, fsnotify_perm(), which is called from the
security code. This hook is used to allow fsnotify groups to make access
control decisions about events on the system. We also must change the
generic fsnotify function to return an error code if we intend these hooks
to be in any way useful.
Signed-off-by: Eric Paris <eparis@redhat.com>
fsnotify was using char * when it passed around the d_name.name string
internally but it is actually an unsigned char *. This patch switches
fsnotify to use unsigned and should silence some pointer signess warnings
which have popped out of xfs. I do not add -Wpointer-sign to the fsnotify
code as there are still issues with kstrdup and strlen which would pop
out needless warnings.
Signed-off-by: Eric Paris <eparis@redhat.com>
fanotify needs to know the actual event added to queues so it can be
correctly checked for return values from userspace. To do this we need to
pass that information from the merger code back to the main even handling
routine. Currently that information is unused, but it will be.
Signed-off-by: Eric Paris <eparis@redhat.com>
Each group can define their own notification (and secondary_q) merge
function. Inotify does tail drop, fanotify does matching and drop which
can actually allocate a completely new event. But for fanotify to properly
deal with permissions events it needs to know the new event which was
ultimately added to the notification queue. This patch just implements a
void ** argument which is passed to the merge function. fanotify can use
this field to pass the new event back to higher layers.
Signed-off-by: Eric Paris <eparis@redhat.com>
for fanotify to properly deal with permissions events
