Commit Graph

264 Commits

Author SHA1 Message Date
Al Viro
d83c49f3e3 Fix the regression created by "set S_DEAD on unlink()..." commit
1) i_flags simply doesn't work for mount/unlink race prevention;
we may have many links to file and rm on one of those obviously
shouldn't prevent bind on top of another later on.  To fix it
right way we need to mark _dentry_ as unsuitable for mounting
upon; new flag (DCACHE_CANT_MOUNT) is protected by d_flags and
i_mutex on the inode in question.  Set it (with dont_mount(dentry))
in unlink/rmdir/etc., check (with cant_mount(dentry)) in places
in namespace.c that used to check for S_DEAD.  Setting S_DEAD
is still needed in places where we used to set it (for directories
getting killed), since we rely on it for readdir/rmdir race
prevention.

2) rename()/mount() protection has another bogosity - we unhash
the target before we'd checked that it's not a mountpoint.  Fixed.

3) ancient bogosity in pivot_root() - we locked i_mutex on the
right directory, but checked S_DEAD on the different (and wrong)
one.  Noticed and fixed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-15 07:16:33 -04:00
Jan Kara
002baeecf5 vfs: Fix O_NOFOLLOW behavior for paths with trailing slashes
According to specification

	mkdir d; ln -s d a; open("a/", O_NOFOLLOW | O_RDONLY)

should return success but currently it returns ELOOP.  This is a
regression caused by path lookup cleanup patch series.

Fix the code to ignore O_NOFOLLOW in case the provided path has trailing
slashes.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: Marius Tolzmann <tolzmann@molgen.mpg.de>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-13 08:46:04 -07:00
Al Viro
3e297b6134 Restore LOOKUP_DIRECTORY hint handling in final lookup on open()
Lose want_dir argument, while we are at it - since now
nd->flags & LOOKUP_DIRECTORY is equivalent to it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-26 12:41:05 -04:00
Jiri Kosina
318ae2edc3 Merge branch 'for-next' into for-linus
Conflicts:
	Documentation/filesystems/proc.txt
	arch/arm/mach-u300/include/mach/debug-macro.S
	drivers/net/qlge/qlge_ethtool.c
	drivers/net/qlge/qlge_main.c
	drivers/net/typhoon.c
2010-03-08 16:55:37 +01:00
Al Viro
781b16775b Fix a dumb typo - use of & instead of &&
We managed to lose O_DIRECTORY testing due to a stupid typo in commit
1f36f774b2 ("Switch !O_CREAT case to use of do_last()")

Reported-by: Walter Sheets <w41ter@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 10:54:48 -08:00
Linus Torvalds
e213e26ab3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits)
  quota: stop using QUOTA_OK / NO_QUOTA
  dquot: cleanup dquot initialize routine
  dquot: move dquot initialization responsibility into the filesystem
  dquot: cleanup dquot drop routine
  dquot: move dquot drop responsibility into the filesystem
  dquot: cleanup dquot transfer routine
  dquot: move dquot transfer responsibility into the filesystem
  dquot: cleanup inode allocation / freeing routines
  dquot: cleanup space allocation / freeing routines
  ext3: add writepage sanity checks
  ext3: Truncate allocated blocks if direct IO write fails to update i_size
  quota: Properly invalidate caches even for filesystems with blocksize < pagesize
  quota: generalize quota transfer interface
  quota: sb_quota state flags cleanup
  jbd: Delay discarding buffers in journal_unmap_buffer
  ext3: quota_write cross block boundary behaviour
  quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota
  quota: split out compat_sys_quotactl support from quota.c
  quota: split out netlink notification support from quota.c
  quota: remove invalid optimization from quota_sync_all
  ...

Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c
2010-03-05 13:20:53 -08:00
Al Viro
1f36f774b2 Switch !O_CREAT case to use of do_last()
... and now we have all intents crap well localized

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:22:25 -05:00
Al Viro
def4af30cf Get rid of symlink body copying
Now that nd->last stays around until ->put_link() is called, we can
just postpone that ->put_link() in do_filp_open() a bit and don't
bother with copying.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:40 -05:00
Al Viro
3866248e5f Finish pulling of -ESTALE handling to upper level in do_filp_open()
Don't bother with path_walk() (and its retry loop); link_path_walk()
will do it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:38 -05:00
Al Viro
806b681cbe Turn do_link spaghetty into a normal loop
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:36 -05:00
Al Viro
10fa8e62f2 Unify exits in O_CREAT handling
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:35 -05:00
Al Viro
9e67f36169 Kill is_link argument of do_last()
We set it to 1 iff we return NULL

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:33 -05:00
Al Viro
67ee3ad21d Pull handling of LAST_BIND into do_last(), clean up ok: part in do_filp_open()
Note that in case of !O_CREAT we know that nd.root has already been given up

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:31 -05:00
Al Viro
4296e2cbf2 Leave mangled flag only for setting nd.intent.open.flag
Nothing else uses it anymore

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:29 -05:00
Al Viro
5b369df826 Get rid of passing mangled flag to do_last()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:27 -05:00
Al Viro
9a66179e13 Don't pass mangled open_flag to finish_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:25 -05:00
Al Viro
a2c36b450e pull more into do_last()
Handling of LAST_DOT/LAST_ROOT/LAST_DOTDOT/terminating slash
can be pulled in as well

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:24 -05:00
Al Viro
c99658fe97 bail out with ELOOP earlier in do_link loop
If we'd passed through 32 trailing symlinks already, there's
no sense following the 33rd - we'll bail out anyway.  Better
bugger off earlier.

It *does* change behaviour, after a fashion - if the 33rd happens
to be a procfs-style symlink, original code *would* allow it.
This one will not.  Cry me a river if that hurts you.  Please, do.
And post a video of that, while you are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:22 -05:00
Al Viro
a1e28038df pull the common predecessors into do_last()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:20 -05:00
Al Viro
c41c140562 postpone __putname() until after do_last()
Since do_last() doesn't mangle nd->last_name, we can safely postpone
__putname() done in handling of trailing symlinks until after the
call of do_last()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:18 -05:00
Al Viro
27bff34300 unroll do_last: loop in do_filp_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:16 -05:00
Al Viro
3343eb8209 Shift releasing nd->root from do_last() to its caller
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:15 -05:00
Al Viro
fb1cc555d5 gut do_filp_open() a bit more (do_last separation)
Brute-force separation of stuff reachable from do_last: with
the exception of do_link:; just take all that crap to a helper
function as-is and have it tell the caller if it has to go
to do_link.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:13 -05:00
Al Viro
648fa8611d beginning to untangle do_filp_open()
That's going to be a long and painful series.  The first step:
take the stuff reachable from 'ok' label in do_filp_open() into
a new helper (finish_open()).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 09:01:11 -05:00
Christoph Hellwig
907f4554e2 dquot: move dquot initialization responsibility into the filesystem
Currently various places in the VFS call vfs_dq_init directly.  This means
we tie the quota code into the VFS.  Get rid of that and make the
filesystem responsible for the initialization.   For most metadata operations
this is a straight forward move into the methods, but for truncate and
open it's a bit more complicated.

For truncate we currently only call vfs_dq_init for the sys_truncate case
because open already takes care of it for ftruncate and open(O_TRUNC) - the
new code causes an additional vfs_dq_init for those which is harmless.

For open the initialization is moved from do_filp_open into the open method,
which means it happens slightly earlier now, and only for regular files.
The latter is fine because we don't need to initialize it for operations
on special files, and we already do it as part of the namespace operations
for directories.

Add a dquot_file_open helper that filesystems that support generic quotas
can use to fill in ->open.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:30 +01:00
Al Viro
9643f5d94a Merge branch 'for-fsnotify' into for-linus 2010-03-03 17:12:40 -05:00
Al Viro
bec1052e5b set S_DEAD on unlink() and non-directory rename() victims
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:12:08 -05:00
Al Viro
3088dd7080 Clean follow_dotdot() up a bit
No need to open-code follow_up() in it and locking can be lighter.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 14:07:56 -05:00
Al Viro
8737c9305b Switch may_open() and break_lease() to passing O_...
... instead of mixing FMODE_ and O_

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-03 13:00:21 -05:00
Al Viro
ac278a9c50 fix LOOKUP_FOLLOW on automount "symlinks"
Make sure that automount "symlinks" are followed regardless of LOOKUP_FOLLOW;
it should have no effect on them.

Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-19 03:56:42 -05:00
Al Viro
cccc6bba3f Lose the first argument of audit_inode_child()
it's always equal to ->d_name.name of the second argument

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-08 14:38:36 -05:00
Al Viro
123df2944c Lose the new_name argument of fsnotify_move()
it's always new_dentry->d_name.name

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-08 14:38:36 -05:00
Mimi Zohar
9bbb6cad01 ima: rename ima_path_check to ima_file_check
ima_path_check actually deals with files!  call it ima_file_check instead.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-07 03:06:22 -05:00
Mimi Zohar
8eb988c70e fix ima breakage
The "Untangling ima mess, part 2 with counters" patch messed
up the counters.  Based on conversations with Al Viro, this patch
streamlines ima_path_check() by removing the counter maintaince.
The counters are now updated independently, from measuring the file,
in __dentry_open() and alloc_file() by calling ima_counts_get().
ima_path_check() is called from nfsd and do_filp_open().
It also did not measure all files that should have been measured.
Reason: ima_path_check() got bogus value passed as mask.
[AV: mea culpa]
[AV: add missing nfsd bits]

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-02-07 03:06:22 -05:00
Adam Buchbinder
c41b20e721 Fix misspellings of "truly" in comments.
Some comments misspell "truly"; this fixes them. No code changes.

Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-02-04 11:55:45 +01:00
Al Viro
9850c05655 Fix the -ESTALE handling in do_filp_open()
Instead of playing sick games with path saving, cleanups, just retry
the entire thing once with LOOKUP_REVAL added.  Post-.34 we'll convert
all -ESTALE handling in there to that style, rather than playing with
many retry loops deep in the call chain.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-14 09:05:26 -05:00
Al Viro
6d125529c6 Fix ACC_MODE() for real
commit 5300990c03 had stepped on a rather
nasty mess: definitions of ACC_MODE used to be different.  Fixed the
resulting breakage, converting them to variant that takes O_... value;
all callers have that and it actually simplifies life (see tomoyo part
of changes).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-14 09:05:26 -05:00
Al Viro
86acdca1b6 fix autofs/afs/etc. magic mountpoint breakage
We end up trying to kfree() nd.last.name on open("/mnt/tmp", O_CREAT)
if /mnt/tmp is an autofs direct mount.  The reason is that nd.last_type
is bogus here; we want LAST_BIND for everything of that kind and we
get LAST_NORM left over from finding parent directory.

So make sure that it *is* set properly; set to LAST_BIND before
doing ->follow_link() - for normal symlinks it will be changed
by __vfs_follow_link() and everything else needs it set that way.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-01-14 09:05:25 -05:00
Serge E. Hallyn
7ea6600148 generic_permission: MAY_OPEN is not write access
generic_permission was refusing CAP_DAC_READ_SEARCH-enabled
processes from opening DAC-protected files read-only, because
do_filp_open adds MAY_OPEN to the open mask.

Ignore MAY_OPEN.  After this patch, CAP_DAC_READ_SEARCH is
again sufficient to open(fname, O_RDONLY) on a file to which
DAC otherwise refuses us read permission.

Reported-by: Mike Kazantsev <mk.fraggod@gmail.com>
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Tested-by: Mike Kazantsev <mk.fraggod@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-30 12:35:44 -08:00
Al Viro
5300990c03 Sanitize f_flags helpers
* pull ACC_MODE to fs.h; we have several copies all over the place
* nightmarish expression calculating f_mode by f_flags deserves a helper
too (OPEN_FMODE(flags))

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-22 12:27:34 -05:00
Al Viro
482928d59d Fix f_flags/f_mode in case of lookup_instantiate_filp() from open(pathname, 3)
Just set f_flags when shoving struct file into nameidata; don't
postpone that until __dentry_open().  do_filp_open() has correct
value; lookup_instantiate_filp() doesn't - we lose the difference
between O_RDWR and 3 by that point.

We still set .intent.open.flags, so no fs code needs to be changed.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-22 12:27:34 -05:00
Jeff Layton
cb59861f03 vfs: remove extraneous NULL d_inode check from do_filp_open
We can't get to this point unless it's a valid pointer.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-17 10:52:34 -05:00
Jeff Layton
39159de2a0 vfs: force reval of target when following LAST_BIND symlinks (try #7)
procfs-style symlinks return a last_type of LAST_BIND without an actual
path string. This causes __follow_link to skip calling __vfs_follow_link
and so the dentry isn't revalidated.

This is a problem when the link target sits on NFSv4 as it depends on
the VFS to revalidate the dentry before using it on an open call. Ensure
that this occurs by forcing a revalidation of the target dentry of
LAST_BIND symlinks.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:48 -05:00
Al Viro
1429b3eca2 Untangling ima mess, part 3: kill dead code in ima
Kill the 'update' argument of ima_path_check(), kill
dead code in ima.

Current rules: ima counters are bumped at the same time
when the file switches from put_filp() fodder to fput()
one.  Which happens exactly in two places - alloc_file()
and __dentry_open().  Nothing else needs to do that at
all.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:47 -05:00
Al Viro
b65a9cfc2c Untangling ima mess, part 2: deal with counters
* do ima_get_count() in __dentry_open()
* stop doing that in followups
* move ima_path_check() to right after nameidata_to_filp()
* don't bump counters on it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:47 -05:00
Al Viro
7715b52122 O_TRUNC open shouldn't fail after file truncation
* take truncate logics into a helper (handle_truncate())
* rip it out of may_open()
* call it from the only caller of may_open() that might pass
O_TRUNC
* and do that after we'd finished with opening.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:47 -05:00
Eric Paris
e81e3f4dca fs: move get_empty_filp() deffinition to internal.h
All users outside of fs/ of get_empty_filp() have been removed.  This patch
moves the definition from the include/ directory to internal.h so no new
users crop up and removes the EXPORT_SYMBOL.  I'd love to see open intents
stop using it too, but that's a problem for another day and a smarter
developer!

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:45 -05:00
Al Viro
b75b5086be Sanitize exec_permission_lite()
Use the sucker in other places in pathname resolution
that check MAY_EXEC for directories; lose the _lite
from name, it's equivalent of full-blown inode_permission()
for its callers (albeit still lighter, since large parts
of generic_permission() do not apply for pure MAY_EXEC).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:45 -05:00
Al Viro
6e6b1bd1e7 Kill cached_lookup() and real_lookup()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:45 -05:00
Al Viro
2dd6d1f418 Kill path_lookup_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-16 12:16:45 -05:00