Commit Graph

160 Commits

Author SHA1 Message Date
David Howells
da9592edeb CRED: Wrap task credential accesses in the filesystem subsystem
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14 10:39:05 +11:00
Miklos Szeredi
f696a3659f [PATCH] move executable checking into ->permission()
For execute permission on a regular files we need to check if file has
any execute bits at all, regardless of capabilites.

This check is normally performed by generic_permission() but was also
added to the case when the filesystem defines its own ->permission()
method.  In the latter case the filesystem should be responsible for
performing this check.

Move the check from inode_permission() inside filesystems which are
not calling generic_permission().

Create a helper function execute_ok() that returns true if the inode
is a directory or if any execute bits are present in i_mode.

Also fix up the following code:

 - coda control file is never executable
 - sysctl files are never executable
 - hfs_permission seems broken on MAY_EXEC, remove
 - hfsplus_permission is eqivalent to generic_permission(), remove

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-10-23 05:13:25 -04:00
OGAWA Hirofumi
4e9ed2f85a [PATCH vfs-2.6 6/6] vfs: add LOOKUP_RENAME_TARGET intent
This adds LOOKUP_RENAME_TARGET intent for lookup of rename destination.

LOOKUP_RENAME_TARGET is going to be used like LOOKUP_CREATE. But since
the destination of rename() can be existing directory entry, so it has a
difference. Although that difference doesn't matter in my usage, this
tells it to user of this intent.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2008-10-23 05:13:20 -04:00
OGAWA Hirofumi
0612d9fb27 [PATCH vfs-2.6 5/6] vfs: remove LOOKUP_PARENT from non LOOKUP_PARENT lookup
lookup_hash() with LOOKUP_PARENT is bogus. And this prepares to add
new intent on those path.

The user of LOOKUP_PARENT intent is nfs only, and it checks whether
nd->flags has LOOKUP_CREATE or LOOKUP_OPEN, so the result is same.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2008-10-23 05:13:19 -04:00
OGAWA Hirofumi
e2761a1167 [PATCH vfs-2.6 2/6] vfs: add d_ancestor()
This adds d_ancestor() instead of d_isparent(), then use it.

If new_dentry == old_dentry, is_subdir() returns 1, looks strange.
"new_dentry == old_dentry" is not subdir obviously. But I'm not
checking callers for now, so this keeps current behavior.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2008-10-23 05:13:16 -04:00
OGAWA Hirofumi
871c0067d5 [PATCH vfs-2.6 1/6] vfs: replace parent == dentry->d_parent by IS_ROOT()
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
2008-10-23 05:13:16 -04:00
Al Viro
3516586a42 [PATCH] make O_EXCL in nd->intent.flags visible in nd->flags
New flag: LOOKUP_EXCL.  Set before doing the final step of pathname
resolution on the paths that have LOOKUP_CREATE and O_EXCL.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-23 05:12:56 -04:00
Al Viro
8737f3a1b3 [PATCH] get rid of path_lookup_create()
... and don't pass bogus flags when we are just looking for parent.
Fold __path_lookup_intent_open() into path_lookup_open() while we
are at it; that's the only remaining caller.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-23 05:12:54 -04:00
Al Viro
d181146572 [PATCH] new helper - kern_path()
Analog of lookup_path(), takes struct path *.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-23 03:34:19 -04:00
Miklos Szeredi
a95164d979 [patch 3/4] vfs: remove unused nameidata argument of may_create()
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-08-01 11:25:30 -04:00
Stephen Smalley
f418b00607 Re: BUG at security/selinux/avc.c:883 (was: Re: linux-next: Tree
for July 17: early crash on x86-64)

SELinux needs MAY_APPEND to be passed down to the security hook.
Otherwise, we get permission denials when only append permission is
granted by policy even if the opening process specified O_APPEND.
Shows up as a regression in the ltp selinux testsuite, fixed by
this patch.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-08-01 11:25:21 -04:00
Al Viro
964bd18362 [PATCH] get rid of __user_path_lookup_open
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:41 -04:00
Al Viro
2ad94ae654 [PATCH] new (local) helper: user_path_parent()
Preparation to untangling intents mess: reduce the number of do_path_lookup()
callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:35 -04:00
Al Viro
2d8f30380a [PATCH] sanitize __user_walk_fd() et.al.
* do not pass nameidata; struct path is all the callers want.
* switch to new helpers:
	user_path_at(dfd, pathname, flags, &path)
	user_path(pathname, &path)
	user_lpath(pathname, &path)
	user_path_dir(pathname, &path)  (fail if not a directory)
  The last 3 are trivial macro wrappers for the first one.
* remove nameidata in callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:34 -04:00
Al Viro
f419a2e3b6 [PATCH] kill nameidata passing to permission(), rename to inode_permission()
Incidentally, the name that gives hundreds of false positives on grep
is not a good idea...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:31 -04:00
Al Viro
30524472c2 [PATCH] take noexec checks to very few callers that care
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:30 -04:00
Al Viro
672b16b2f6 [PATCH] more nameidata removal: exec_permission_lite() doesn't need it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:23 -04:00
Al Viro
b77b0646ef [PATCH] pass MAY_OPEN to vfs_permission() explicitly
... and get rid of the last "let's deduce mask from nameidata->flags"
bit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:22 -04:00
Al Viro
a110343f0d [PATCH] fix MAY_CHDIR/MAY_ACCESS/LOOKUP_ACCESS mess
* MAY_CHDIR is redundant - it's an equivalent of MAY_ACCESS
* MAY_ACCESS on fuse should affect only the last step of pathname resolution
* fchdir() and chroot() should pass MAY_ACCESS, for the same reason why
  chdir() needs that.
* now that we pass MAY_ACCESS explicitly in all cases, LOOKUP_ACCESS can be
  removed; it has no business being in nameidata.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:21 -04:00
Al Viro
7f2da1e7d0 [PATCH] kill altroot
long overdue...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:20 -04:00
Al Viro
8bb79224b8 [PATCH] permission checks for chdir need special treatment only on the last step
... so we ought to pass MAY_CHDIR to vfs_permission() instead of having
it triggered on every step of preceding pathname resolution.  LOOKUP_CHDIR
is killed by that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:19 -04:00
Miklos Szeredi
db2e747b14 [patch 5/5] vfs: remove mode parameter from vfs_symlink()
Remove the unused mode parameter from vfs_symlink and callers.

Thanks to Tetsuo Handa for noticing.

CC: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-07-26 20:53:18 -04:00
Tetsuo Handa
7e79eedb3b [patch 4/5] vfs: reuse local variable in vfs_link()
Why not reuse "inode" which is assigned as

  struct inode *inode = old_dentry->d_inode;

in the beginning of vfs_link() ?

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-07-26 20:53:17 -04:00
Al Viro
e6305c43ed [PATCH] sanitize ->permission() prototype
* kill nameidata * argument; map the 3 bits in ->flags anybody cares
  about to new MAY_... ones and pass with the mask.
* kill redundant gfs2_iop_permission()
* sanitize ecryptfs_permission()
* fix remaining places where ->permission() instances might barf on new
  MAY_... found in mask.

The obvious next target in that direction is permission(9)

folded fix for nfs_permission() breakage from Miklos Szeredi <mszeredi@suse.cz>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:14 -04:00
Miklos Szeredi
d70b67c8bc [patch] vfs: fix lookup on deleted directory
Lookup can install a child dentry for a deleted directory.  This keeps
the directory dentry alive, and the inode pinned in the cache and on
disk, even after all external references have gone away.

This isn't a big problem normally, since memory pressure or umount
will clear out the directory dentry and its children, releasing the
inode.  But for UBIFS this causes problems because its orphan area can
overflow.

Fix this by returning ENOENT for all lookups on a S_DEAD directory
before creating a child dentry.

Thanks to Zoltan Sogor for noticing this while testing UBIFS, and
Artem for the excellent analysis of the problem and testing.

Reported-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Tested-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26 20:53:05 -04:00
Marcin Slusarz
694a1764d6 [patch 3/4] vfs: fix ERR_PTR abuse in generic_readlink
generic_readlink calls ERR_PTR for negative and positive values
(vfs_readlink returns length of "link"), but it should not
(not an errno) and does not need to.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:30 -04:00
Jan Blunck
c8e7f449b2 [patch 1/4] vfs: path_{get,put}() cleanups
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-23 11:52:29 -04:00
Al Viro
e9baf6e598 [PATCH] return to old errno choice in mkdir() et.al.
In case when both EEXIST and EROFS would apply we used to
return the former in mkdir(2) and friends.  Lest anyone suspects
us of being consistent, in the same situation knfsd gave clients
nfs_erofs...

	ro-bind series had switched the syscall side of things to
returning -EROFS and immediately broke an application - namely,
mkdir -p.  Patch restores the original behaviour...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-05-16 17:23:18 -04:00
Serge E. Hallyn
08ce5f16ee cgroups: implement device whitelist
Implement a cgroup to track and enforce open and mknod restrictions on device
files.  A device cgroup associates a device access whitelist with each cgroup.
 A whitelist entry has 4 fields.  'type' is a (all), c (char), or b (block).
'all' means it applies to all types and all major and minor numbers.  Major
and minor are either an integer or * for all.  Access is a composition of r
(read), w (write), and m (mknod).

The root device cgroup starts with rwm to 'all'.  A child devcg gets a copy of
the parent.  Admins can then remove devices from the whitelist or add new
entries.  A child cgroup can never receive a device access which is denied its
parent.  However when a device access is removed from a parent it will not
also be removed from the child(ren).

An entry is added using devices.allow, and removed using
devices.deny.  For instance

	echo 'c 1:3 mr' > /cgroups/1/devices.allow

allows cgroup 1 to read and mknod the device usually known as
/dev/null.  Doing

	echo a > /cgroups/1/devices.deny

will remove the default 'a *:* mrw' entry.

CAP_SYS_ADMIN is needed to change permissions or move another task to a new
cgroup.  A cgroup may not be granted more permissions than the cgroup's parent
has.  Any task can move itself between cgroups.  This won't be sufficient, but
we can decide the best way to adequately restrict movement later.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix may-be-used-uninitialized warning]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Looks-good-to: Pavel Emelyanov <xemul@openvz.org>
Cc: Daniel Hokka Zakrisson <daniel@hozac.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:09 -07:00
Dave Hansen
4a3fd211cc [PATCH] r/o bind mounts: elevate write count for open()s
This is the first really tricky patch in the series.  It elevates the writer
count on a mount each time a non-special file is opened for write.

We used to do this in may_open(), but Miklos pointed out that __dentry_open()
is used as well to create filps.  This will cover even those cases, while a
call in may_open() would not have.

There is also an elevated count around the vfs_create() call in open_namei().
See the comments for more details, but we need this to fix a 'create, remount,
fail r/w open()' race.

Some filesystems forego the use of normal vfs calls to create
struct files.   Make sure that these users elevate the mnt
writer count because they will get __fput(), and we need
to make sure they're balanced.

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:29:25 -04:00
Dave Hansen
9079b1eb17 [PATCH] r/o bind mounts: get write access for vfs_rename() callers
This also uses the little helper in the NFS code to make an if() a little bit
less ugly.  We introduced the helper at the beginning of the series.

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:34 -04:00
Dave Hansen
75c3f29de7 [PATCH] r/o bind mounts: write counts for link/symlink
[AV: add missing nfsd pieces]

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:34 -04:00
Dave Hansen
463c319726 [PATCH] r/o bind mounts: get callers of vfs_mknod/create/mkdir()
This takes care of all of the direct callers of vfs_mknod().
Since a few of these cases also handle normal file creation
as well, this also covers some calls to vfs_create().

So that we don't have to make three mnt_want/drop_write()
calls inside of the switch statement, we move some of its
logic outside of the switch and into a helper function
suggested by Christoph.

This also encapsulates a fix for mknod(S_IFREG) that Miklos
found.

[AV: merged mkdir handling, added missing nfsd pieces]

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:34 -04:00
Dave Hansen
0622753b80 [PATCH] r/o bind mounts: elevate write count for rmdir and unlink.
Elevate the write count during the vfs_rmdir() and vfs_unlink().

[AV: merged rmdir and unlink parts, added missing pieces in nfsd]

Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:33 -04:00
Christoph Hellwig
a70e65df88 [PATCH] merge open_namei() and do_filp_open()
open_namei() will, in the future, need to take mount write counts
over its creation and truncation (via may_open()) operations.  It
needs to keep these write counts until any potential filp that is
created gets __fput()'d.

This gets complicated in the error handling and becomes very murky
as to how far open_namei() actually got, and whether or not that
mount write count was taken.  That makes it a bad interface.

All that the current do_filp_open() really does is allocate the
nameidata on the stack, then call open_namei().

So, this merges those two functions and moves filp_open() over
to namei.c so it can be close to its buddy: do_filp_open().  It
also gets a kerneldoc comment in the process.

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:32 -04:00
Dave Hansen
d57999e152 [PATCH] do namei_flags calculation inside open_namei()
My end goal here is to make sure all users of may_open()
return filps.  This will ensure that we properly release
mount write counts which were taken for the filp in
may_open().

This patch moves the sys_open flags to namei flags
calculation into fs/namei.c.  We'll shortly be moving
the nameidata_to_filp() calls into namei.c, and this
gets the sys_open flags to a place where we can get
at them when we need them.

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19 00:25:31 -04:00
Linus Torvalds
7ed7fe5e82 Merge branch 'for-linus' of 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:
  [PATCH] get stack footprint of pathname resolution back to relative sanity
  [PATCH] double iput() on failure exit in hugetlb
  [PATCH] double dput() on failure exit in tiny-shmem
  [PATCH] fix up new filp allocators
  [PATCH] check for null vfsmount in dentry_open()
  [PATCH] reiserfs: eliminate private use of struct file in xattr
  [PATCH] sanitize hppfs
  hppfs pass vfsmount to dentry_open()
  [PATCH] restore export of do_kern_mount()
2008-03-25 08:57:47 -07:00
Randy Dunlap
a6b91919e0 fs: fix kernel-doc notation warnings
Fix kernel-doc notation warnings in fs/.

Warning(mmotm-2008-0314-1449//fs/super.c:560): missing initial short description on line:
 *	mark_files_ro
Warning(mmotm-2008-0314-1449//fs/locks.c:1277): missing initial short description on line:
 *	lease_get_mtime
Warning(mmotm-2008-0314-1449//fs/locks.c:1277): missing initial short description on line:
 *	lease_get_mtime
Warning(mmotm-2008-0314-1449//fs/namei.c:1368): missing initial short description on line:
 * lookup_one_len:  filesystem helper to lookup single pathname component
Warning(mmotm-2008-0314-1449//fs/buffer.c:3221): missing initial short description on line:
 * bh_uptodate_or_lock: Test whether the buffer is uptodate
Warning(mmotm-2008-0314-1449//fs/buffer.c:3240): missing initial short description on line:
 * bh_submit_read: Submit a locked buffer for reading
Warning(mmotm-2008-0314-1449//fs/fs-writeback.c:30): missing initial short description on line:
 * writeback_acquire: attempt to get exclusive writeback access to a device
Warning(mmotm-2008-0314-1449//fs/fs-writeback.c:47): missing initial short description on line:
 * writeback_in_progress: determine whether there is writeback in progress
Warning(mmotm-2008-0314-1449//fs/fs-writeback.c:58): missing initial short description on line:
 * writeback_release: relinquish exclusive writeback access against a device.
Warning(mmotm-2008-0314-1449//include/linux/jbd.h:351): contents before sections
Warning(mmotm-2008-0314-1449//include/linux/jbd.h:561): contents before sections
Warning(mmotm-2008-0314-1449//fs/jbd/transaction.c:1935): missing initial short description on line:
 * void journal_invalidatepage()

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-19 18:53:36 -07:00
Al Viro
a02f76c34d [PATCH] get stack footprint of pathname resolution back to relative sanity
Somebody had put struct nameidata in stack frame of link_path_walk().
Unfortunately, there are certain realities to deal with:
	* It's in the middle of recursion.  Depth is equal to the nesting
depth of symlinks, i.e. up to 8.
	* struct namiedata is, even if one discards the intent junk,
at least 12 pointers + 5 ints.
	* moreover, adding a stack frame is not free in that situation.
	* there are fs methods called on top of that, and they also have
stack footprint.
	* kernel stack is not infinite.

The thing is, even if one chooses to deal with -ESTALE that way (and it's
one hell of an overkill), the only thing that needs to be preserved is
vfsmount + dentry, not the entire struct nameidata.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-19 06:55:46 -04:00
Jan Blunck
6ac08c39a1 Use struct path in fs_struct
* Use struct path in fs_struct.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
5dd784d049 Introduce path_get()
This introduces the symmetric function to path_put() for getting a reference
to the dentry and vfsmount of a struct path in the right order.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
09da5916ba Use path_put() in a few places instead of {mnt,d}put()
Use path_put() in a few places instead of {mnt,d}put()

Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
1d957f9bf8 Introduce path_put()
* Add path_put() functions for releasing a reference to the dentry and
  vfsmount of a struct path in the right order

* Switch from path_release(nd) to path_put(&nd->path)

* Rename dput_path() to path_put_conditional()

[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
4ac9137858 Embed a struct path into struct nameidata instead of nd->{dentry,mnt}
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.

Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
  <dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
  struct path in every place where the stack can be traversed
- it reduces the overall code size:

without patch series:
   text    data     bss     dec     hex filename
5321639  858418  715768 6895825  6938d1 vmlinux

with patch series:
   text    data     bss     dec     hex filename
5320026  858418  715768 6894212  693284 vmlinux

This patch:

Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:33 -08:00
Jan Blunck
429731b155 Remove path_release_on_umount()
path_release_on_umount() should only be called from sys_umount(). I merged the
function into sys_umount() instead of having in in namei.c.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:13:32 -08:00
Harvey Harrison
fc9b52cd8f fs: remove fastcall, it is always empty
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:31 -08:00
Jan Kara
ece95912db inotify: send IN_ATTRIB events when link count changes
Currently, no notification event has been sent when inode's link count
changed.  This is inconvenient for the application in some cases:

Suppose you have the following directory structure

    foo/test
    bar/

and you watch test.  If someone does "mv foo/test bar/", you get event
IN_MOVE_SELF and you know something has happened with the file "test".
However if someone does "ln foo/test bar/test" and "rm foo/test" you get no
inotify event for the file "test" (only directories "foo" and "bar" receive
events).

Furthermore it could be argued that link count belongs to file's metadata and
thus IN_ATTRIB should be sent when it changes.

The following patch implements sending of IN_ATTRIB inotify events when link
count of the inode changes, i.e., when a hardlink to the inode is created or
when it is removed.  This event is sent in addition to all the events sent so
far.  In particular, when a last link to a file is removed, IN_ATTRIB event is
sent in addition to IN_DELETE_SELF event.

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Morten Welinder <mwelinder@gmail.com>
Cc: Robert Love <rlove@google.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-06 10:41:05 -08:00
Linus Torvalds
974a9f0b47 Use access mode instead of open flags to determine needed permissions
Way back when (in commit 834f2a4a15, aka
"VFS: Allow the filesystem to return a full file pointer on open intent"
to be exact), Trond changed the open logic to keep track of the original
flags to a file open, in order to pass down the the intent of a dentry
lookup to the low-level filesystem.

However, when doing that reorganization, it changed the meaning of
namei_flags, and thus inadvertently changed the test of access mode for
directories (and RO filesystem) to use the wrong flag.  So fix those
test back to use access mode ("acc_mode") rather than the open flag
("flag").

Issue noticed by Bill Roman at Datalight.

Reported-and-tested-by: Bill Roman <bill.roman@datalight.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-12 14:47:58 -08:00
Al Viro
5a190ae697 [PATCH] pass dentry to audit_inode()/audit_inode_child()
makes caller simpler *and* allows to scan ancestors

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-10-21 02:37:18 -04:00
Miklos Szeredi
d139d7ffd0 VFS: allow filesystems to implement atomic open+truncate
Add a new attribute flag ATTR_OPEN, with the meaning: "truncation was
initiated by open() due to the O_TRUNC flag".

This way filesystems wanting to implement truncation within their ->open()
method can ignore such truncate requests.

This is a quick & dirty hack, but it comes for free.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:30 -07:00