Skip to content

L
linux

Linux-御风守护者 / linux
与 Fork 源项目一致

从无法访问的项目Fork

通知 1
Star 0
Fork 0
L
linux

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 20 7月, 2007 1 次提交
    • J
      fs: introduce vfs_path_lookup · 16f18200
      由 Josef 'Jeff' Sipek 提交于 
      Stackable file systems, among others, frequently need to lookup paths or
path components starting from an arbitrary point in the namespace
(identified by a dentry and a vfsmount).  Currently, such file systems use
lookup_one_len, which is frowned upon [1] as it does not pass the lookup
intent along; not passing a lookup intent, for example, can trigger BUG_ON's
when stacking on top of NFSv4.

The first patch introduces a new lookup function to allow lookup starting
from an arbitrary point in the namespace.  This approach has been suggested
by Christoph Hellwig [2].

The second patch changes sunrpc to use vfs_path_lookup.

The third patch changes nfsctl.c to use vfs_path_lookup.

The fourth patch marks link_path_walk static.

The fifth, and last patch, unexports path_walk because it is no longer
unnecessary to call it directly, and using the new vfs_path_lookup is
cleaner.

For example, the following snippet of code, looks up "some/path/component"
in a directory pointed to by parent_{dentry,vfsmnt}:

err = vfs_path_lookup(parent_dentry, parent_vfsmnt,
		      "some/path/component", 0, &nd);
if (!err) {
	/* exits */

	...

	/* once done, release the references */
	path_release(&nd);
} else if (err == -ENOENT) {
	/* doesn't exist */
} else {
	/* other error */
}

VFS functions such as lookup_create can be used on the nameidata structure
to pass the create intent to the file system.
Signed-off-by: NJosef 'Jeff' Sipek <jsipek@cs.sunysb.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: NChristoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      16f18200
  3. 18 7月, 2007 1 次提交
    • S
      Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check · 3bd858ab
      由 Satyam Sharma 提交于 
      Introduce is_owner_or_cap() macro in fs.h, and convert over relevant
users to it. This is done because we want to avoid bugs in the future
where we check for only effective fsuid of the current task against a
file's owning uid, without simultaneously checking for CAP_FOWNER as
well, thus violating its semantics.
[ XFS uses special macros and structures, and in general looked ...
untouchable, so we leave it alone -- but it has been looked over. ]

The (current->fsuid != inode->i_uid) check in generic_permission() and
exec_permission_lite() is left alone, because those operations are
covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations
falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone.
Signed-off-by: NSatyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: NSerge E. Hallyn <serge@hallyn.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      3bd858ab
  5. 11 5月, 2007 1 次提交
  7. 10 5月, 2007 2 次提交
  9. 09 5月, 2007 2 次提交
  11. 08 5月, 2007 1 次提交
  13. 28 4月, 2007 1 次提交
  15. 17 2月, 2007 1 次提交
  17. 13 2月, 2007 1 次提交
  19. 09 12月, 2006 2 次提交
  21. 08 12月, 2006 2 次提交
  23. 01 10月, 2006 2 次提交
  25. 30 9月, 2006 1 次提交
  27. 27 9月, 2006 1 次提交
    • I
      [PATCH] autofs4 needs to force fail return revalidate · bcdc5e01
      由 Ian Kent 提交于 
      For a long time now I have had a problem with not being able to return a
lookup failure on an existsing directory.  In autofs this corresponds to a
mount failure on a autofs managed mount entry that is browsable (and so the
mount point directory exists).

While this problem has been present for a long time I've avoided resolving
it because it was not very visible.  But now that autofs v5 has "mount and
expire on demand" of nested multiple mounts, such as is found when mounting
an export list from a server, solving the problem cannot be avoided any
longer.

I've tried very hard to find a way to do this entirely within the autofs4
module but have not been able to find a satisfactory way to achieve it.

So, I need to propose a change to the VFS.
Signed-off-by: NIan Kent <raven@themaw.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      bcdc5e01
  29. 25 9月, 2006 1 次提交
  31. 25 8月, 2006 2 次提交
    • T
      VFS: Fix access("file", X_OK) in the presence of ACLs · a343bb77
      由 Trond Myklebust 提交于 
      Currently, the access() call will return incorrect information on NFS if
there exists an ACL that grants execute access to the user on a regular
file. The reason the information is incorrect is that the VFS overrides
this execute access in open_exec() by checking (inode->i_mode & 0111).

This patch propagates the VFS execute bit check back into the generic
permission() call.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 64cbae98848c4c99851cb0a405f0b4982cd76c1e commit)
      a343bb77
    • A
      VFS: add lookup hint for network file systems · a634904a
      由 ASANO Masahiro 提交于 
      I'm trying to speeding up mkdir(2) for network file systems.  A typical
mkdir(2) calls two inode_operations: lookup and mkdir.  The lookup
operation would fail with ENOENT in common case.  I think it is unnecessary
because the subsequent mkdir operation can check it.  In case of creat(2),
lookup operation is called with the LOOKUP_CREATE flag, so individual
filesystem can omit real lookup.  e.g.  nfs_lookup().

Here is a sample patch which uses LOOKUP_CREATE and O_EXCL on mkdir,
symlink and mknod.  This uses the gadget for creat(2).

And here is the result of a benchmark on NFSv3.
  mkdir(2) 10,000 times:
    original  50.5 sec
    patched   29.0 sec
Signed-off-by: NASANO Masahiro <masano@tnes.nec.co.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from fab7bf44449b29f9d5572a5dd8adcf7c91d5bf0f commit)
      a634904a
  33. 03 8月, 2006 3 次提交
  35. 15 7月, 2006 1 次提交
    • K
      [PATCH] struct file leakage · de459215
      由 Kirill Korotaev 提交于 
      2.6.16 leaks like hell. While testing, I found massive leakage
(reproduced in openvz) in:

*filp
*size-4096

And 1 object leaks in
*size-32
*size-64
*size-128

It is the fix for the first one.  filp leaks in the bowels of namei.c.

Seems, size-4096 is file table leaking in expand_fdtables.

I have no idea what are the rest and why they show only accompanying
another leaks.  Some debugging structs?

[akpm@osdl.org, Trond: remove the IS_ERR() check]
Signed-off-by: NAlexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: <stable@kernel.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      de459215
  37. 04 7月, 2006 1 次提交
  39. 26 6月, 2006 1 次提交
    • U
      [PATCH] Implement AT_SYMLINK_FOLLOW flag for linkat · 45c9b11a
      由 Ulrich Drepper 提交于 
      When the linkat() syscall was added the flag parameter was added in the
last minute but it wasn't used so far.  The following patch should change
that.  My tests show that this is all that's needed.

If OLDNAME is a symlink setting the flag causes linkat to follow the
symlink and create a hardlink with the target.  This is actually the
behavior POSIX demands for link() as well but Linux wisely does not do
this.  With this flag (which will most likely be in the next POSIX
revision) the programmer can choose the behavior, defaulting to the safe
variant.  As a side effect it is now possible to implement a
POSIX-compliant link(2) function for those who are interested.

  touch file
  ln -s file symlink

  linkat(fd, "symlink", fd, "newlink", 0)
    -> newlink is hardlink of symlink

  linkat(fd, "symlink", fd, "newlink", AT_SYMLINK_FOLLOW)
    -> newlink is hardlink of file

The value of AT_SYMLINK_FOLLOW is determined by the definition we already
use in glibc.
Signed-off-by: NUlrich Drepper <drepper@redhat.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      45c9b11a
  41. 23 6月, 2006 1 次提交
  43. 20 6月, 2006 1 次提交
    • A
      [PATCH] log more info for directory entry change events · 9c937dcc
      由 Amy Griffis 提交于 
      When an audit event involves changes to a directory entry, include
a PATH record for the directory itself.  A few other notable changes:

    - fixed audit_inode_child() hooks in fsnotify_move()
    - removed unused flags arg from audit_inode()
    - added audit log routines for logging a portion of a string

Here's some sample output.

before patch:
type=SYSCALL msg=audit(1149821605.320:26): arch=40000003 syscall=39 success=yes exit=0 a0=bf8d3c7c a1=1ff a2=804e1b8 a3=bf8d3c7c items=1 ppid=739 pid=800 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149821605.320:26):  cwd="/root"
type=PATH msg=audit(1149821605.320:26): item=0 name="foo" parent=164068 inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0

after patch:
type=SYSCALL msg=audit(1149822032.332:24): arch=40000003 syscall=39 success=yes exit=0 a0=bfdd9c7c a1=1ff a2=804e1b8 a3=bfdd9c7c items=2 ppid=714 pid=777 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255
type=CWD msg=audit(1149822032.332:24):  cwd="/root"
type=PATH msg=audit(1149822032.332:24): item=0 name="/root" inode=164068 dev=03:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_dir_t:s0
type=PATH msg=audit(1149822032.332:24): item=1 name="foo" inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0
Signed-off-by: NAmy Griffis <amy.griffis@hp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      9c937dcc
  45. 06 6月, 2006 1 次提交
  47. 01 4月, 2006 1 次提交
  49. 28 3月, 2006 1 次提交
    • I
      [PATCH] autofs4: nameidata needs to be up to date for follow_link · 051d3812
      由 Ian Kent 提交于 
      In order to be able to trigger a mount using the follow_link inode method the
nameidata struct that is passed in needs to have the vfsmount of the autofs
trigger not its parent.

During a path walk if an autofs trigger is mounted on a dentry, when the
follow_link method is called, the nameidata struct contains the vfsmount and
mountpoint dentry of the parent mount while the dentry that is passed in is
the root of the autofs trigger mount.  I believe it is impossible to get the
vfsmount of the trigger mount, within the follow_link method, when only the
parent vfsmount and the root dentry of the trigger mount are known.

This patch updates the nameidata struct on entry to __do_follow_link if it
detects that it is out of date.  It moves the path_to_nameidata to above
__do_follow_link to facilitate calling it from there.  The dput_path is moved
as well as that seemed sensible.  No changes are made to these two functions.
Signed-off-by: NIan Kent <raven@themaw.net>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      051d3812
  51. 26 3月, 2006 2 次提交
    • N
      [PATCH] Honour AOP_TRUNCATE_PAGE returns in page_symlink · 7e53cac4
      由 NeilBrown 提交于 
      As prepare_write, commit_write and readpage are allowed to return
AOP_TRUNCATE_PAGE, page_symlink should respond to them.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      7e53cac4
    • O
      [PATCH] Missed error checking for intent's filp in open_namei(). · 4af4c52f
      由 Oleg Drokin 提交于 
      It seems there is error check missing in open_namei for errors returned
through intent.open.file (from lookup_instantiate_filp).

If there is plain open performed, then such a check done inside
__path_lookup_intent_open called from path_lookup_open(), but when the open
is performed with O_CREAT flag set, then __path_lookup_intent_open is only
called with LOOKUP_PARENT set where no file opening can occur yet.

Later on lookup_hash is called where exact opening might take place and
intent.open.file may be filled.  If it is filled with error value of some
sort, then we get kernel attempting to dereference this error value as
address (and corresponding oops) in nameidata_to_filp() called from
filp_open().

While this is relatively simple to workaround in ->lookup() method by just
checking lookup_instantiate_filp() return value and returning error as
needed, this is not so easy in ->d_revalidate(), where we can only return
"yes, dentry is valid" or "no, dentry is invalid, perform full lookup
again", and just returning 0 on error would cause extra lookup (with
potential extra costly RPCs).

So in short, I believe that there should be no difference in error handling
for opening a file and creating a file in open_namei() and propose this
simple patch as a solution.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      4af4c52f
  53. 23 3月, 2006 1 次提交
  55. 21 3月, 2006 2 次提交
  57. 12 3月, 2006 1 次提交
  59. 25 2月, 2006 1 次提交
    • U
      [PATCH] flags parameter for linkat · c04030e1
      由 Ulrich Drepper 提交于 
      I'm currently at the POSIX meeting and one thing covered was the
incompatibility of Linux's link() with the POSIX definition.  The name.
Linux does not follow symlinks, POSIX requires it does.

Even if somebody thinks this is a good default behavior we cannot change this
because it would break the ABI.  But the fact remains that some application
might want this behavior.

We have one chance to help implementing this without breaking the behavior.
 For this we could use the new linkat interface which would need a new
flags parameter.  If the new parameter is AT_SYMLINK_FOLLOW the new
behavior could be invoked.

I do not want to introduce such a patch now.  But we could add the
parameter now, just don't use it.  The patch below would do this.  Can we
get this late patch applied before the release more or less fixes the
syscall API?
Signed-off-by: NUlrich Drepper <drepper@redhat.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      c04030e1