The user.* extended attributes are only allowed on regular files and
directories. Sticky directories further restrict write access to the owner
and privileged users. (See the attr(5) man page for an explanation.)
The original check in ext2/ext3 when user.* xattrs were merged was more
restrictive than intended, and when the xattr permission checks were moved
into the VFS, read access to user.* attributes on sticky directores ended
up being denied in addition.
Originally-from: Gerard Neil <xyzzy@devferret.org>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch moves code out of fs/xattr.c:listxattr into a new function -
vfs_listxattr. The code for vfs_listxattr was originally submitted by Bill
Nottingham <notting@redhat.com> to Unionfs.
Sorry about that. The reason for this submission is to make the
listxattr code in fs/xattr.c a little cleaner (as well as to clean up
some code in Unionfs.)
Currently, Unionfs has vfs_listxattr defined in its code. I think
that's very ugly, and I'd like to see it (re)moved. The logical place
to put it, is along side of all the other vfs_*xattr functions.
Overall, I think this patch is benefitial for both kernel.org kernel and
Unionfs.
Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch augments the collection of inode info during syscall
processing. It represents part of the functionality that was provided
by the auditfs patch included in RHEL4.
Specifically, it:
- Collects information for target inodes created or removed during
syscalls. Previous code only collects information for the target
inode's parent.
- Adds the audit_inode() hook to syscalls that operate on a file
descriptor (e.g. fchown), enabling audit to do inode filtering for
these calls.
- Modifies filtering code to check audit context for either an inode #
or a parent inode # matching a given rule.
- Modifies logging to provide inode # for both parent and child.
- Protect debug info from NULL audit_names.name.
[AV: folded a later typo fix from the same author]
Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
)
From: Christoph Hellwig <hch@lst.de>
The xattr code has rather complex permission checks because the rules are very
different for different attribute namespaces. This patch moves as much as we
can into the generic code. Currently all the major disk based filesystems
duplicate these checks, while many minor filesystems or network filesystems
lack some or all of them.
To do this we need defines for the extended attribute names in common code, I
moved them up from JFS which had the nicest defintions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add vfs_getxattr, vfs_setxattr and vfs_removexattr helpers for common checks
around invocation of the xattr methods. NFSD already was missing some of the
checks and there will be more soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: James Morris <jmorris@namei.org>
(James, I haven't touched selinux yet because it's doing various odd things
and I'm not sure how it would interact with the security attribute fallbacks
you added. Could you investigate whether it could use vfs_getxattr or if not
add a __vfs_getxattr helper to share the bits it is fine with?)
For NFSv4: instead of just converting it add an nfsd_getxattr helper for the
code shared by NFSv2/3 and NFSv4 ACLs. In fact that code isn't even
NFS-specific, but I'll wait for more users to pop up first before moving it to
common code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.
Modified-by: Ingo Molnar <mingo@elte.hu>
(finished the conversion)
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit f549d6c18c introduced a generic
fallback for security xattrs, but appears to include a subtle bug.
Gentoo users with kernels with selinux compiled in, and coreutils compiled
with acl support, noticed that they could not copy files on tmpfs using
'cp'.
cp (compiled with acl support) copies the file, lists the extended
attributes on the old file, copies them all to the new file, and then
exits. However the listxattr() calls were failing with this odd behaviour:
llistxattr("a.out", (nil), 0) = 17
llistxattr("a.out", 0x7fffff8c6cb0, 17) = -1 ERANGE (Numerical result out of
range)
I believe this is a simple problem in the logic used to check the buffer
sizes; if the user sends a buffer the exact size of the data, then its ok
:)
This change solves the problem.
More info can be found at http://bugs.gentoo.org/113138
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is the fs/ part of the big kfree cleanup patch.
Remove pointless checks for NULL prior to calling kfree() in fs/.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch allows SELinux to canonicalize the value returned from
getxattr() via the security_inode_getsecurity() hook, which is called after
the fs level getxattr() function.
The purpose of this is to allow the in-core security context for an inode
to override the on-disk value. This could happen in cases such as
upgrading a system to a different labeling form (e.g. standard SELinux to
MLS) without needing to do a full relabel of the filesystem.
In such cases, we want getxattr() to return the canonical security context
that the kernel is using rather than what is stored on disk.
The implementation hooks into the inode_getsecurity(), adding another
parameter to indicate the result of the preceding fs-level getxattr() call,
so that SELinux knows whether to compare a value obtained from disk with
the kernel value.
We also now allow getxattr() to work for mountpoint labeled filesystems
(i.e. mount with option context=foo_t), as we are able to return the
kernel value to the user.
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add fsnotify_xattr() hook to removexattr().
Signed-off-by: Robert Love <rml@novell.com>
Signed-off-by: John McCtuchan <ttb@tentacle.dhs.org>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch modifies the VFS setxattr, getxattr, and listxattr code to fall
back to the security module for security xattrs if the filesystem does not
support xattrs natively. This allows security modules to export the incore
inode security label information to userspace even if the filesystem does
not provide xattr storage, and eliminates the need to individually patch
various pseudo filesystem types to provide such access. The patch removes
the existing xattr code from devpts and tmpfs as it is then no longer
needed.
The patch restructures the code flow slightly to reduce duplication between
the normal path and the fallback path, but this should only have one
user-visible side effect - a program may get -EACCES rather than
-EOPNOTSUPP if policy denied access but the filesystem didn't support the
operation anyway. Note that the post_setxattr hook call is not needed in
the fallback case, as the inode_setsecurity hook call handles the incore
inode security state update directly. In contrast, we do call fsnotify in
both cases.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:
* dnotify requires the opening of one fd per each directory
that you intend to watch. This quickly results in too many
open files and pins removable media, preventing unmount.
* dnotify is directory-based. You only learn about changes to
directories. Sure, a change to a file in a directory affects
the directory, but you are then forced to keep a cache of
stat structures.
* dnotify's interface to user-space is awful. Signals?
inotify provides a more usable, simple, powerful solution to file change
notification:
* inotify's interface is a system call that returns a fd, not SIGIO.
You get a single fd, which is select()-able.
* inotify has an event that says "the filesystem that the item
you were watching is on was unmounted."
* inotify can watch directories or files.
Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.
See Documentation/filesystems/inotify.txt.
Signed-off-by: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Andreas Gruenbacher