| Commit message (Collapse) | Author | Age | Files | Lines |
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* 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linux:
unistd: add __NR_prlimit64 syscall numbers
rlimits: implement prlimit64 syscall
rlimits: switch more rlimit syscalls to do_prlimit
rlimits: redo do_setrlimit to more generic do_prlimit
rlimits: add rlimit64 structure
rlimits: do security check under task_lock
rlimits: allow setrlimit to non-current tasks
rlimits: split sys_setrlimit
rlimits: selinux, do rlimits changes under task_lock
rlimits: make sure ->rlim_max never grows in sys_setrlimit
rlimits: add task_struct to update_rlimit_cpu
rlimits: security, add task_struct to setrlimit
Fix up various system call number conflicts. We not only added fanotify
system calls in the meantime, but asm-generic/unistd.h added a wait4
along with a range of reserved per-architecture system calls.
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This patch adds the code to support the sys_prlimit64 syscall which
modifies-and-returns the rlim values of a selected process atomically.
The first parameter, pid, being 0 means current process.
Unlike the current implementation, it is a generic interface,
architecture indepentent so that we needn't handle compat stuff
anymore. In the future, after glibc start to use this we can deprecate
sys_setrlimit and sys_getrlimit in favor to clean up the code finally.
It also adds a possibility of changing limits of other processes. We
check the user's permissions to do that and if it succeeds, the new
limits are propagated online. This is good for large scale
applications such as SAP or databases where administrators need to
change limits time by time (e.g. on crashes increase core size). And
it is unacceptable to restart the service.
For safety, all rlim users now either use accessors or doesn't need
them due to
- locking
- the fact a process was just forked and nobody else knows about it
yet (and nobody can't thus read/write limits)
hence it is safe to modify limits now.
The limitation is that we currently stay at ulong internal
representation. So the rlim64_is_infinity check is used where value is
compared against ULONG_MAX on 32-bit which is the maximum value there.
And since internally the limits are held in struct rlimit, converters
which are used before and after do_prlimit call in sys_prlimit64 are
introduced.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
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After we added more generic do_prlimit, switch sys_getrlimit to that.
Also switch compat handling, so we can get rid of ugly __user casts
and avoid setting process' address limit to kernel data and back.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
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It now allows also reading of limits. I.e. all read and writes will
later use this function.
It takes two parameters, new and old limits which can be both NULL.
If new is non-NULL, the value in it is set to rlimits.
If old is non-NULL, current rlimits are stored there.
If both are non-NULL, old are stored prior to setting the new ones,
atomically.
(Similar to sigaction.)
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
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Do security_task_setrlimit under task_lock. Other tasks may change
limits under our hands while we are checking limits inside the
function. From now on, they can't.
Note that all the security work is done under a spinlock here now.
Security hooks count with that, they are called from interrupt context
(like security_task_kill) and with spinlocks already held (e.g.
capable->security_capable).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: James Morris <jmorris@namei.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
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Add locking to allow setrlimit accept task parameter other than
current.
Namely, lock tasklist_lock for read and check whether the task
structure has sighand non-null. Do all the signal processing under
that lock still held.
There are some points:
1) security_task_setrlimit is now called with that lock held. This is
not new, many security_* functions are called with this lock held
already so it doesn't harm (all this security_* stuff does almost
the same).
2) task->sighand->siglock (in update_rlimit_cpu) is nested in
tasklist_lock. This dependence is already existing.
3) tsk->alloc_lock is nested in tasklist_lock. This is OK too, already
existing dependence.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
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Create do_setrlimit from sys_setrlimit and declare do_setrlimit
in the resource header. This is the first phase to have generic
do_prlimit which allows to be called from read, write and compat
rlimits code.
The new do_setrlimit also accepts a task pointer to change the limits
of. Currently, it cannot be other than current, but this will change
with locking later.
Also pass tsk->group_leader to security_task_setrlimit to check
whether current is allowed to change rlimits of the process and not
its arbitrary thread because it makes more sense given that rlimit are
per process and not per-thread.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
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Mostly preparation for Jiri's changes, but probably makes sense anyway.
sys_setrlimit() checks new_rlim.rlim_max <= old_rlim->rlim_max, but when
it takes task_lock() old_rlim->rlim_max can be already lowered. Move this
check under task_lock().
Currently this is not important, we can only race with our sub-thread,
this means the application is stupid. But when we change the code to allow
the update of !current task's limits, it becomes important to make sure
->rlim_max can be lowered "reliably" even if we race with the application
doing sys_setrlimit().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
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Add task_struct as a parameter to update_rlimit_cpu to be able to set
rlimit_cpu of different task than current.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
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Add task_struct to task_setrlimit of security_operations to be able to set
rlimit of task other than current.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
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* 'for-linus' of git://git.infradead.org/users/eparis/notify: (132 commits)
fanotify: use both marks when possible
fsnotify: pass both the vfsmount mark and inode mark
fsnotify: walk the inode and vfsmount lists simultaneously
fsnotify: rework ignored mark flushing
fsnotify: remove global fsnotify groups lists
fsnotify: remove group->mask
fsnotify: remove the global masks
fsnotify: cleanup should_send_event
fanotify: use the mark in handler functions
audit: use the mark in handler functions
dnotify: use the mark in handler functions
inotify: use the mark in handler functions
fsnotify: send fsnotify_mark to groups in event handling functions
fsnotify: Exchange list heads instead of moving elements
fsnotify: srcu to protect read side of inode and vfsmount locks
fsnotify: use an explicit flag to indicate fsnotify_destroy_mark has been called
fsnotify: use _rcu functions for mark list traversal
fsnotify: place marks on object in order of group memory address
vfs/fsnotify: fsnotify_close can delay the final work in fput
fsnotify: store struct file not struct path
...
Fix up trivial delete/modify conflict in fs/notify/inotify/inotify.c.
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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audit now gets a mark in the should_send_event and handle_event
functions. Rather than look up the mark themselves audit should just use
the mark it was handed.
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <eparis@redhat.com>
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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>
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Extern declarations in sysctl.c should be move to their own head file, and
then include them in relavant .c files.
Move inotify_table extern declaration to linux/inotify.h
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
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Move dir_notify_enable declaration to where it belongs -- dnotify.h .
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
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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.c
Signed-off-by: Eric Paris <eparis@redhat.com>
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This patch simply declares the new sys_fanotify_mark syscall
int fanotify_mark(int fanotify_fd, unsigned int flags, u64_mask,
int dfd const char *pathname)
Signed-off-by: Eric Paris <eparis@redhat.com>
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This patch defines a new syscall fanotify_init() of the form:
int sys_fanotify_init(unsigned int flags, unsigned int event_f_flags,
unsigned int priority)
This syscall is used to create and fanotify group. This is very similar to
the inotify_init() syscall.
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
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the _entry portion of fsnotify functions is useless. Drop it.
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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Nothing uses the mask argument to fsnotify_alloc_group. This patch drops
that argument.
Signed-off-by: Eric Paris <eparis@redhat.com>
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Currently the audit watch group always sets a mask equal to all events it
might care about. We instead should only set the group mask if we are
actually watching inodes. This should be a perf win when audit watches are
compiled in.
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 <eparis@redhat.com>
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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 available
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <eparis@redhat.com>
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nothing uses inotify in the kernel, drop it!
Signed-off-by: Eric Paris <eparis@redhat.com>
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Audit watch init and fsnotify init both use subsys_initcall() but since the
audit watch code is linked in before the fsnotify code the audit watch code
would be using the fsnotify srcu struct before it was initialized. This
patch fixes that problem by moving audit watch init to device_initcall() so
it happens after fsnotify is ready.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Eric Paris <eparis@redhat.com>
Tested-by : Sachin Sant <sachinp@in.ibm.com>
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Audit watch should depend on CONFIG_AUDIT_SYSCALL and should select
FSNOTIFY. This splits the spagetti like mixing of audit_watch and
audit_filter code so they can be configured seperately.
Signed-off-by: Eric Paris <eparis@redhat.com>
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Simply switch audit_trees from using inotify to using fsnotify for it's
inode pinning and disappearing act information.
Signed-off-by: Eric Paris <eparis@redhat.com>
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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 <eparis@redhat.com>
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deleting audit watch rules is not currently done under audit_filter_mutex.
It was done this way because we could not hold the mutex during inotify
manipulation. Since we are using fsnotify we don't need to do the extra
get/put pair nor do we need the private list on which to store the parents
while they are about to be freed.
Signed-off-by: Eric Paris <eparis@redhat.com>
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fsnotify can handle mutexes to be held across all fsnotify operations since
it deals strickly in spinlocks. This can simplify and reduce some of the
audit_filter_mutex taking and dropping.
Signed-off-by: Eric Paris <eparis@redhat.com>
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Audit currently uses inotify to pin inodes in core and to detect when
watched inodes are deleted or unmounted. This patch uses fsnotify instead
of inotify.
Signed-off-by: Eric Paris <eparis@redhat.com>
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No real changes, just cleanup to the audit_watch split patch which we done
with minimal code changes for easy review. Now fix interfaces to make
things work better.
Signed-off-by: Eric Paris <eparis@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
no need for list_for_each_entry_safe()/resetting with superblock list
Fix sget() race with failing mount
vfs: don't hold s_umount over close_bdev_exclusive() call
sysv: do not mark superblock dirty on remount
sysv: do not mark superblock dirty on mount
btrfs: remove junk sb_dirt change
BFS: clean up the superblock usage
AFFS: wait for sb synchronization when needed
AFFS: clean up dirty flag usage
cifs: truncate fallout
mbcache: fix shrinker function return value
mbcache: Remove unused features
add f_flags to struct statfs(64)
pass a struct path to vfs_statfs
update VFS documentation for method changes.
All filesystems that need invalidate_inode_buffers() are doing that explicitly
convert remaining ->clear_inode() to ->evict_inode()
Make ->drop_inode() just return whether inode needs to be dropped
fs/inode.c:clear_inode() is gone
fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
...
Fix up trivial conflicts in fs/nilfs2/super.c
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We'll need the path to implement the flags field for statvfs support.
We do have it available in all callers except:
- ecryptfs_statfs. This one doesn't actually need vfs_statfs but just
needs to do a caller to the lower filesystem statfs method.
- sys_ustat. Add a non-exported statfs_by_dentry helper for it which
doesn't won't be able to fill out the flags field later on.
In addition rename the helpers for statfs vs fstatfs to do_*statfs instead
of the misleading vfs prefix.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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kmsg_dump takes care to sample the global variables
inside a spinlock, but then goes on to use the same
variables outside the spinlock region too.
Use the correct variable. This will make the race
window smaller.
Found by gcc 4.6's new warnings.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Reorder elements in structure cpu_stopper to remove alignment padding on
64 bit builds, this shrinks its size from 40 to 32 bytes saving 8 bytes
per cpu.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Remove duplicate definition of ARRAY_SIZE(), which was never used anyway.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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sys_personality()->__set_personality() path
Cleanup, no functional changes.
- __set_personality() always changes ->exec_domain/personality, the
special case when ->exec_domain remains the same buys nothing but
complicates the code. Unify both cases to simplify the code.
- The -EINVAL check in sys_personality() was never right. If we assume
that set_personality() can fail we should check the value it returns
instead of verifying that task->personality was actually changed.
Remove it. Before the previous patch it was possible to hit this case
due to overflow problems, but this -EINVAL just indicated the kernel
bug.
OTOH, probably it makes sense to change lookup_exec_domain() to return
ERR_PTR() instead of default_exec_domain if the search in exec_domains
list fails, and report this error to the user-space. But this means
another user-space change, and we have in-kernel users which need fixes.
For example, PER_OSF4 falls into PER_MASK for unkown reason and nobody
cares to register this domain.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Wenming Zhang <wezhang@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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When taking a memory snapshot in hibernate_snapshot(), all (directly
called) memory allocations use GFP_ATOMIC. Hence swap misusage during
hibernation never occurs.
But from a pessimistic point of view, there is no guarantee that no page
allcation has __GFP_WAIT. It is better to have a global indication "we
enter hibernation, don't use swap!".
This patch tries to freeze new-swap-allocation during hibernation. (All
user processes are frozenm so swapin is not a concern).
This way, no updates will happen to swap_map[] between
hibernate_snapshot() and save_image(). Swap is thawed when swsusp_free()
is called. We can be assured that swap corruption will not occur.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Hugh Dickins <hughd@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Ondrej Zary <linux@rainbow-software.org>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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