CIFS currently allows you to change the mode of an inode on a share that
doesn't have unix extensions enabled, and isn't using cifsacl. The inode
in this case *only* has its mode changed in memory on the client. This
is problematic since it can change any time the inode is purged from the
cache.
This patch makes cifs_setattr silently ignore most mode changes when
unix extensions and cifsacl support are not enabled, and when the share
is not mounted with the "dynperm" option. The exceptions are:
When a mode change would remove all write access to an inode we turn on
the ATTR_READONLY bit on the server and remove all write bits from the
inode's mode in memory.
When a mode change would add a write bit to an inode that previously had
them all turned off, it turns off the ATTR_READONLY bit on the server,
and resets the mode back to what it would normally be (generally, the
file_mode or dir_mode of the share).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
CIFS currently allows you to change the ownership of a file, but unless
unix extensions are enabled this change is not passed off to the server.
Have CIFS silently ignore ownership changes that can't be persistently
stored on the server unless the "setuids" option is explicitly
specified.
We could return an error here (-EOPNOTSUPP or something), but this is
how most disk-based windows filesystems on behave on Linux (e.g. VFAT,
NTFS, etc). With cifsacl support and proper Windows to Unix idmapping
support, we may be able to do this more properly in the future.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When CIFS creates a new inode on a mount without unix extensions, it
temporarily assigns the mode that was passed to it in the create/mkdir
call. Eventually, when the inode is revalidated, it changes to have the
file_mode or dir_mode for the mount. This is confusing to users who
expect that the mode shouldn't change this way. It's also problematic
since only the mode is treated this way, not the uid or gid. Suppose you
have a CIFS mount that's mounted with:
uid=0,gid=0,file_mode=0666,dir_mode=0777
...if an unprivileged user comes along and does this on the mount:
mkdir -m 0700 foo
touch foo/bar
...there is a period of time where the touch will fail, since the dir
will initially be owned by root and have mode 0700. If the user waits
long enough, then "foo" will be revalidated and will get the correct
dir_mode permissions.
This patch changes cifs_mkdir and cifs_create to not overwrite the
mode found by the initial cifs_get_inode_info call after the inode is
created on the server. Legacy behavior can be reenabled with the
new "dynperm" mount option.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When mounting a share with posix extensions disabled,
cifs_get_inode_info turns off all the write bits in the mode for regular
files if ATTR_READONLY is set. Directories and other inode types,
however, can also have ATTR_READONLY set, but the mode gives no
indication of this.
This patch makes this apply to other inode types besides regular files.
It also cleans up how modes are set in cifs_get_inode_info for both the
"normal" and "dynperm" cases.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Final piece for handling DFS in query_path_info, constructing a
fake inode for the junction directory which the submount will cover.
This handles the non-Unix (Windows etc.) code path.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Final piece for handling DFS in unix_query_path_info, constructing a
fake inode for the junction directory which the submount will cover.
Acked-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Some versions of Samba (3.2-pre e.g.) are stricter about checking to make sure that
paths in DFS name spaces are sent in the form \\server\share\dir\subdir ...
instead of \dir\subdir
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
SMBLegacyOpen always opens a file as r/w. This could be problematic
for files with ATTR_READONLY set. Have it interpret the access_mode
into a sane open mode.
Signed-off-by: Steve French <sfrench@us.ibm.com>
When creating a directory on a CIFS share without POSIX extensions,
and the given mode has no write bits set, set the ATTR_READONLY bit.
When creating a file, set ATTR_READONLY if the create mode has no write
bits set and we're not using unix extensions.
There are some comments about this being problematic due to the VFS
splitting creates into 2 parts. I'm not sure what that's actually
talking about, but I'm assuming that it has something to do with how
mknod is implemented. In the simple case where we have no unix
extensions and we're just creating a regular file, there's no reason
we can't set ATTR_READONLY.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Clean up cifs_setattr a bit by adding a local inode pointer, and
changing all of the direntry->d_inode references to it. This also adds a
bit of micro-optimization. d_inode shouldn't change over the life of
this function, so we only need to dereference it once.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The current logic in cifs_setattr calls mode_to_acl twice on mode
changes if cifsacl is enabled. Remove the duplicate call.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When a share was in DFS and the server was Unix/Linux, we were sending paths of the form
\\server\share/dir/file
rather than
//server/share/dir/file
There was some discussion between me and jra over whether we should use
/server/share/dir/file
as MS sometimes says - but the documentation for this claims it should be
doubleslash for this type of UNC-like path format and that works, so leaving
it as doubleslash but converting the \ to / in the the //server/share portion.
This gets Samba to now correctly return STATUS_PATH_NOT_COVERED when it is
supposed to (Windows already did since the direction of the slash was not an issue
for them). Still need another minor change to fully enable DFS (need to finish
some chages to SMBGetDFSRefer
Signed-off-by: Steve French <sfrench@us.ibm.com>
Shirish Pargaonkar noted:
With cifsacl mount option, when a file is created on the Windows server,
exclusive oplock is broken right away because the get cifs acl code
again opens the file to obtain security descriptor.
The client does not have the newly created file handle or inode in any
of its lists yet so it does not respond to oplock break and server waits for
its duration and then responds to the second open. This slows down file
creation signficantly. The fix is to pass the file descriptor to the get
cifsacl code wherever available so that get cifs acl code does not send
second open (NT Create ANDX) and oplock is not broken.
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Kukks noticed that cp -p can write out file data too late, after the timestamp
is already set. This was introduced as an unintentional sideeffect of the change
in an earlier patch (see below) which fixed some delayed return code propagation.
cea218054a
Author: Jeff Layton <jlayton@redhat.com>
Date: Tue Nov 20 23:19:03 2007 +0000
Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Christoph had noticed too many ifdefs in the CIFS code making it
hard to read. This patch removes about a quarter of them from
the C files in cifs by improving a few key ifdefs in the .h files.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Stop the CIFS filesystem from using iget() and read_inode(). Replace
cifs_read_inode() with cifs_iget(), and call that instead of iget().
cifs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.
cifs_read_super() now returns any error incurred when getting the root inode
instead of ENOMEM.
cifs_iget() needs examining. The comment "can not call macro FreeXid here
since in a void func" is no longer true.
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
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>
Simplify page cache zeroing of segments of pages through 3 functions
zero_user_segments(page, start1, end1, start2, end2)
Zeros two segments of the page. It takes the position where to
start and end the zeroing which avoids length calculations and
makes code clearer.
zero_user_segment(page, start, end)
Same for a single segment.
zero_user(page, start, length)
Length variant for the case where we know the length.
We remove the zero_user_page macro. Issues:
1. Its a macro. Inline functions are preferable.
2. The KM_USER0 macro is only defined for HIGHMEM.
Having to treat this special case everywhere makes the
code needlessly complex. The parameter for zeroing is always
KM_USER0 except in one single case that we open code.
Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.
Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.
Also extract the flushing of the caches to be outside of the kmap.
[akpm@linux-foundation.org: fix nfs and ntfs build]
[akpm@linux-foundation.org: fix ntfs build some more]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Requires cifsacl mount flag to be on and CIFS_EXPERIMENTAL enabled
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Fix RedHat bug 329431
The idea here is separate "conscious" from "unconscious" flushes.
Conscious flushes are those due to a fsync() or close(). Unconscious
ones are flushes that occur as a side effect of some other operation or
due to memory pressure.
Currently, when an error occurs during an unconscious flush (ENOSPC or
EIO), we toss out the page and don't preserve that error to report to
the user when a conscious flush occurs. If after the unconscious flush,
there are no more dirty pages for the inode, the conscious flush will
simply return success even though there were previous errors when writing
out pages. This can lead to data corruption.
The easiest way to reproduce this is to mount up a CIFS share that's
very close to being full or where the user is very close to quota. mv
a file to the share that's slightly larger than the quota allows. The
writes will all succeed (since they go to pagecache). The mv will do a
setattr to set the new file's attributes. This calls
filemap_write_and_wait,
which will return an error since all of the pages can't be written out.
Then later, when the flush and release ops occur, there are no more
dirty pages in pagecache for the file and those operations return 0. mv
then assumes that the file was written out correctly and deletes the
original.
CIFS already has a write_behind_rc variable where it stores the results
from earlier flushes, but that value is only reported in cifs_close.
Since the VFS ignores the return value from the release operation, this
isn't helpful. We should be reporting this error during the flush
operation.
This patch does the following:
1) changes cifs_fsync to use filemap_write_and_wait and cifs_flush and also
sync to check its return code. If it returns successful, they then check
the value of write_behind_rc to see if an earlier flush had reported any
errors. If so, they return that error and clear write_behind_rc.
2) sets write_behind_rc in a few other places where pages are written
out as a side effect of other operations and the code waits on them.
3) changes cifs_setattr to only call filemap_write_and_wait for
ATTR_SIZE changes.
4) makes cifs_writepages accurately distinguish between EIO and ENOSPC
errors when writing out pages.
Some simple testing indicates that the patch works as expected and that
it fixes the reproduceable known problem.
Acked-by: Dave Kleikamp <shaggy@austin.rr.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
We were requesting GENERIC_READ but that fails when we do not have
read permission on the file (even if we could read the ACL).
Also move the dump access control entry code into debug ifdef.
Signed-off-by: Steve French <sfrench@us.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (51 commits)
[CIFS] log better errors on failed mounts
[CIFS] Return better error when server requires signing but client forbids
[CIFS] fix typo
[CIFS] acl support part 4
[CIFS] Fix minor problems noticed by scan
[CIFS] fix bad handling of EAGAIN error on kernel_recvmsg in cifs_demultiplex_thread
[CIFS] build break
[CIFS] endian fixes
[CIFS] endian fixes in new acl code
[CIFS] Fix some endianness problems in new acl code
[CIFS] missing #endif from a previous patch
[CIFS] formatting fixes
[CIFS] Break up unicode_sessetup string functions
[CIFS] parse server_GUID in SPNEGO negProt response
[CIFS]
[CIFS] Fix endian conversion problem in posix mkdir
[CIFS] fix build break when lanman not enabled
[CIFS] remove two sparse warnings
[CIFS] remove compile warnings when debug disabled
[CIFS] CIFS ACL support part 3
...
If the ATTR_KILL_S*ID bits are set then any mode change is only for clearing
the setuid/setgid bits. For CIFS, skip the mode change and let the server
handle it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows cifs to mount to ipc shares (IPC$)
which will allow user space applications to
layer over authenticated cifs connections
(useful for Wine and others that would want
to put DCE/RPC over CIFS or run CIFS named
pipes)
Acked-by: Rob Shearman <rob@codeweavers.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
There is a small memory leak in fs/cifs/inode.c::cifs_mkdir().
Storage for 'pInfo' is allocated with kzalloc(), but if the call
to CIFSPOSIXCreate(...) happens to return 0 and pInfo->Type == -1,
then we'll jump to the 'mkdir_get_info' label without freeing the
storage allocated for 'pInfo'.
This patch adds a kfree() call to free the storage just before
jumping to the label, thus getting rid of the leak.
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When making a directory with POSIX mkdir calls, cifs_mkdir does not
respect the umask. This patch causes the new POSIX mkdir to create with
the right mode
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
vmtruncate had added the same fix to handle the case of private pages
being Copy on writed while truncate_inode_pages is going on
Signed-off-by: Steve French <sfrench@us.ibm.com>
Previously the only way to do this was to umount all mounts to that server,
turn off a proc setting (/proc/fs/cifs/LinuxExtensionsEnabled).
Fixes Samba bugzilla bug number: 4582 (and also 2008)
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
In the cleanup phase of the dbench test, we were noticing sharing
violation followed by failed directory removals when dbench
did not close the test files before the cleanup phase started.
Using the new POSIX unlink, which Samba has supported for a few
months, avoids this.
Signed-off-by: Steve French <sfrench@us.ibm.com>
This should be the last big batch of whitespace/formatting fixes.
checkpatch warnings for the cifs directory are down about 90% and
many of the remaining ones are harder to remove or make the code
harder to read.
Signed-off-by: Steve French <sfrench@us.ibm.com>
