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1483 commits

Author SHA1 Message Date
Shirish Pargaonkar
3d3ea8e64e cifs: Add mount options for backup intent (try #6)
Add mount options backupuid and backugid.

It allows an authenticated user to access files with the intent to back them
up including their ACLs, who may not have access permission but has
"Backup files and directories user right" on them (by virtue of being part
of the built-in group Backup Operators.

When mount options backupuid is specified, cifs client restricts the
use of backup intents to the user whose effective user id is specified
along with the mount option.

When mount options backupgid is specified, cifs client restricts the
use of backup intents to the users whose effective user id belongs to the
group id specified along with the mount option.

If an authenticated user is not part of the built-in group Backup Operators
at the server, access to such files is denied, even if allowed by the client.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:42:17 -05:00
Suresh Jayaraman
8bc4392a1e cifs: warn about deprecation of /proc/fs/cifs/OplockEnabled interface
The plan is to deprecate this interface by kernel version 3.4.

Changes since v1
   - add a '\n' to the printk.

Reported-by: Alexander Swen <alex@swen.nu>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:42:13 -05:00
Suresh Jayaraman
c9c4708fdf cifs: update README about the kernel module parameters
Reported-by: Alexander Swen <alex@swen.nu>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:42:09 -05:00
Steve French
e75047344e add new module parameter 'enable_oplocks'
Thus spake Jeff Layton:

"Making that a module parm would allow you to set that parameter at boot
time without needing to add special startup scripts. IMO, all of the
procfile "switches" under /proc/fs/cifs should be module parms
instead."

This patch doesn't alter the default behavior (Oplocks are enabled by
default).

To disable oplocks when loading the module, use

   modprobe cifs enable_oplocks=0

(any of '0' or 'n' or 'N' conventions can be used).

To disable oplocks at runtime using the new interface, use

   echo 0 > /sys/module/cifs/parameters/enable_oplocks

The older /proc/fs/cifs/OplockEnabled interface will be deprecated
after two releases. A subsequent patch will add an warning message
about this deprecation.

Changes since v2:
   - make enable_oplocks a 'bool'

Changes since v1:
   - eliminate the use of extra variable by renaming the old one to
     enable_oplocks and make it an 'int' type.

Reported-by: Alexander Swen <alex@swen.nu>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:42:05 -05:00
Jeff Layton
ba749e6d52 cifs: check for unresponsive server every time we call kernel_recvmsg
If the server stops sending data while in the middle of sending a
response then we still want to reconnect it if it doesn't come back.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:59 -05:00
Jeff Layton
e831e6cf3a cifs: make smb_msg local to read_from_socket
If msg_controllen is 0, then the socket layer should never touch these
fields. Thus, there's no need to continually reset them. Also, there's
no need to keep this field on the stack for the demultiplex thread, just
make it a local variable in read_from_socket.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:54 -05:00
Jeff Layton
e2218eab20 cifs: trivial: remove obsolete comment
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:47 -05:00
Jeff Layton
826a95e4a3 cifs: consolidate signature generating code
We have two versions of signature generating code. A vectorized and
non-vectorized version. Eliminate a large chunk of cut-and-paste
code by turning the non-vectorized version into a wrapper around the
vectorized one.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:41 -05:00
Jeff Layton
376b43f41c cifs: clean up checkSMB
The variable names in this function are so ambiguous that it's very
difficult to know what it's doing. Rename them to make it a bit more
clear.

Also, remove a redundant length check. cifsd checks to make sure that
the rfclen isn't larger than the maximum frame size when it does the
receive.

Finally, change checkSMB to return a real error code (-EIO) when
it finds an error. That will help simplify some coming changes in the
callers.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:36 -05:00
Jeff Layton
c974befa40 cifs: untangle server->maxBuf and CIFSMaxBufSize
server->maxBuf is the maximum SMB size (including header) that the
server can handle. CIFSMaxBufSize is the maximum amount of data (sans
header) that the client can handle. Currently maxBuf is being capped at
CIFSMaxBufSize + the max headers size, and the two values are used
somewhat interchangeably in the code.

This makes little sense as these two values are not related at all.
Separate them and make sure the code uses the right values in the right
places.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:32 -05:00
Paul Bolle
f3a6a60e4c cifs: Fix typo 'CIFS_NFSD_EXPORT'
It should be 'CONFIG_CIFS_NFSD_EXPORT'. No-one noticed because that
symbol depends on BROKEN.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:27 -05:00
Jeff Layton
4a29a0bd1d cifs: get rid of unused xid in cifs_get_root
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:22 -05:00
Jeff Layton
b4dacbc282 cifs: use memcpy for magic string in cifs signature generation BSRSPYL
...it's more efficient since we know the length.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:18 -05:00
Jeff Layton
ac423446d8 cifs: switch CIFSSMBQAllEAs to use memcmp
...as that's more efficient when we know that the lengths are equal.

Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-12 23:41:14 -05:00
Sachin Prabhu
875cd04381 cifs: Display strictcache mount option in /proc/mounts
Commit d39454ffe4 adds a strictcache mount
option. This patch allows the display of this mount option in
/proc/mounts when listing shares mounted with the strictcache mount
option.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-11 13:13:18 -05:00
Steve French
9d1e397b7b [CIFS] Fix first time message on mount, ntlmv2 upgrade delayed to 3.2
Microsoft has a bug with ntlmv2 that requires use of ntlmssp, but
we didn't get the required information on when/how to use ntlmssp to
old (but once very popular) legacy servers (various NT4 fixpacks
for example) until too late to merge for 3.1.  Will upgrade
to NTLMv2 in NTLMSSP in 3.2

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
2011-10-07 20:17:56 -05:00
Shirish Pargaonkar
cfbd6f84c2 cifs: Fix broken sec=ntlmv2/i sec option (try #2)
Fix sec=ntlmv2/i authentication option during mount of Samba shares.

cifs client was coding ntlmv2 response incorrectly.
All that is needed in temp as specified in MS-NLMP seciton 3.3.2

"Define ComputeResponse(NegFlg, ResponseKeyNT, ResponseKeyLM,
CHALLENGE_MESSAGE.ServerChallenge, ClientChallenge, Time, ServerName)

as
Set temp to ConcatenationOf(Responserversion, HiResponserversion,
Z(6), Time, ClientChallenge, Z(4), ServerName, Z(4)"

is MsvAvNbDomainName.

For sec=ntlmsspi, build_av_pair is not used, a blob is plucked from
type 2 response sent by the server to use in authentication.

I tested sec=ntlmv2/i and sec=ntlmssp/i mount options against
Samba (3.6) and Windows - XP, 2003 Server and 7.
They all worked.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:16:58 -05:00
Steve French
c9c7fa0064 Fix the conflict between rwpidforward and rw mount options
Both these options are started with "rw" - that's why the first one
isn't switched on even if it is specified. Fix this by adding a length
check for "rw" option check.

Cc: <stable@kernel.org>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:16:20 -05:00
Pavel Shilovsky
5b980b0121 CIFS: Fix ERR_PTR dereference in cifs_get_root
move it to the beginning of the loop.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:15:03 -05:00
Jeff Layton
9438fabb73 cifs: fix possible memory corruption in CIFSFindNext
The name_len variable in CIFSFindNext is a signed int that gets set to
the resume_name_len in the cifs_search_info. The resume_name_len however
is unsigned and for some infolevels is populated directly from a 32 bit
value sent by the server.

If the server sends a very large value for this, then that value could
look negative when converted to a signed int. That would make that
value pass the PATH_MAX check later in CIFSFindNext. The name_len would
then be used as a length value for a memcpy. It would then be treated
as unsigned again, and the memcpy scribbles over a ton of memory.

Fix this by making the name_len an unsigned value in CIFSFindNext.

Cc: <stable@kernel.org>
Reported-by: Darren Lavender <dcl@hppine99.gbr.hp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:14:40 -05:00
Steve French
04c05b4a68 update cifs version to 1.75
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-18 16:55:10 +00:00
Steve French
13589c437d [CIFS] possible memory corruption on mount
CIFS cleanup_volume_info_contents() looks like having a memory
corruption problem.
When UNCip is set to "&vol->UNC[2]" in cifs_parse_mount_options(), it
should not be kfree()-ed in cleanup_volume_info_contents().

Introduced in commit b946845a9d

Signed-off-by: J.R. Okajima <hooanon05@yahoo.co.jp>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
CC: Stable <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-18 16:53:02 +00:00
Jeff Layton
fa71f44706 cifs: demote cERROR in build_path_from_dentry to cFYI
Running the cthon tests on a recent kernel caused this message to pop
occasionally:

    CIFS VFS: did not end path lookup where expected namelen is 0

Some added debugging showed that namelen and dfsplen were both 0 when
this occurred. That means that the read_seqretry returned true.

Assuming that the comment inside the if statement is true, this should
be harmless and just means that we raced with a rename. If that is the
case, then there's no need for alarm and we can demote this to cFYI.

While we're at it, print the dfsplen too so that we can see what
happened here if the message pops during debugging.

Cc: stable@kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-16 13:07:24 +00:00
Shirish Pargaonkar
e22906c564 cifs: Do not set cifs/ntfs acl using a file handle (try #4)
Set security descriptor using path name instead of a file handle.
We can't be sure that the file handle has adequate permission to
set a security descriptor (to modify DACL).

Function set_cifs_acl_by_fid() has been removed since we can't be
sure how a file was opened for writing, a valid request can fail
if the file was not opened with two above mentioned permissions.
We could have opted to add on WRITE_DAC and WRITE_OWNER permissions
to file opens and then use that file handle but adding addtional
permissions such as WRITE_DAC and WRITE_OWNER could cause an
any open to fail.

And it was incorrect to look for read file handle to set a
security descriptor anyway.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-11 18:23:45 +00:00
Steve French
789e666123 [CIFS] Cleanup use of CONFIG_CIFS_STATS2 ifdef to make transport routines more readable
Christoph had requested that the stats related code (in
CONFIG_CIFS_STATS2) be moved into helpers to make code flow more
readable.   This patch should help.   For example the following
section from transport.c

                       spin_unlock(&GlobalMid_Lock);
                       atomic_inc(&ses->server->num_waiters);
                       wait_event(ses->server->request_q,
                                  atomic_read(&ses->server->inFlight)
                                    < cifs_max_pending);
                       atomic_dec(&ses->server->num_waiters);
                       spin_lock(&GlobalMid_Lock);

becomes simpler (with the patch below):
                       spin_unlock(&GlobalMid_Lock);
                       cifs_num_waiters_inc(server);
                       wait_event(server->request_q,
                                  atomic_read(&server->inFlight)
                                    < cifs_max_pending);
                       cifs_num_waiters_dec(server);
                       spin_lock(&GlobalMid_Lock);

Reviewed-by: Jeff Layton <jlayton@redhat.com>
CC: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
2011-08-11 18:23:45 +00:00
Jeff Layton
80975d21aa cifs: cope with negative dentries in cifs_get_root
The loop around lookup_one_len doesn't handle the case where it might
return a negative dentry, which can cause an oops on the next pass
through the loop. Check for that and break out of the loop with an
error of -ENOENT if there is one.

Fixes the panic reported here:

    https://bugzilla.redhat.com/show_bug.cgi?id=727927

Reported-by: TR Bentley <home@trarbentley.net>
Reported-by: Iain Arnell <iarnell@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-05 15:03:09 +00:00
Jeff Layton
f9e8c45002 cifs: convert prefixpath delimiters in cifs_build_path_to_root
Regression from 2.6.39...

The delimiters in the prefixpath are not being converted based on
whether posix paths are in effect. Fixes:

    https://bugzilla.redhat.com/show_bug.cgi?id=727834

Reported-and-Tested-by: Iain Arnell <iarnell@gmail.com>
Reported-by: Patrick Oltmann <patrick.oltmann@gmx.net>
Cc: Pavel Shilovsky <piastryyy@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-05 14:55:15 +00:00
Pavel Shilovsky
0193e07226 CIFS: Fix missing a decrement of inFlight value
if we failed on getting mid entry in cifs_call_async.

Cc: stable@kernel.org
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-03 19:42:12 +00:00
Jeff Layton
b802898334 cifs: demote DFS referral lookup errors to cFYI
cifs: demote DFS referral lookup errors to cFYI

Now that we call into this routine on every mount, anyone who doesn't
have the upcall configured will get multiple printks about failed lookups.

Reported-and-Tested-by: Martijn Uffing <mp3project@sarijopen.student.utwente.nl>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-03 03:19:28 +00:00
Steve French
fc05a78efb Revert "cifs: advertise the right receive buffer size to the server"
This reverts commit c4d3396b26.

Problems discovered with readdir to Samba due to
not accounting for header size properly with this change
2011-08-03 03:17:43 +00:00
Pavel Shilovsky
762dfd1057 CIFS: Cleanup demupltiplex thread exiting code
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-01 12:49:45 +00:00
Pavel Shilovsky
ad69bae178 CIFS: Move mid search to a separate function
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-01 12:49:42 +00:00
Pavel Shilovsky
98bac62c9f CIFS: Move RFC1002 check to a separate function
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-01 12:49:38 +00:00
Pavel Shilovsky
e7015fb1c5 CIFS: Simplify socket reading in demultiplex thread
Move reading to separate function and remove csocket variable.

Also change semantic in a little: goto incomplete_rcv only when
we get -EAGAIN (or a familiar error) while reading rfc1002 header.
In this case we don't check for echo timeout when we don't get whole
header at once, as it was before.

Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-01 12:49:34 +00:00
Pavel Shilovsky
3d9c2472a5 CIFS: Move buffer allocation to a separate function
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-08-01 12:33:44 +00:00
Jeff Layton
c4a5534a1b cifs: remove unneeded variable initialization in cifs_reconnect_tcon
Reported-and-acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:27:16 +00:00
Jeff Layton
ad635942c8 cifs: simplify refcounting for oplock breaks
Currently, we take a sb->s_active reference and a cifsFileInfo reference
when an oplock break workqueue job is queued. This is unnecessary and
more complicated than it needs to be. Also as Al points out,
deactivate_super has non-trivial locking implications so it's best to
avoid that if we can.

Instead, just cancel any pending oplock breaks for this filehandle
synchronously in cifsFileInfo_put after taking it off the lists.
That should ensure that this job doesn't outlive the structures it
depends on.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:21:20 +00:00
Jeff Layton
5980fc966b cifs: fix compiler warning in CIFSSMBQAllEAs
The recent fix to the above function causes this compiler warning to pop
on some gcc versions:

  CC [M]  fs/cifs/cifssmb.o
fs/cifs/cifssmb.c: In function ‘CIFSSMBQAllEAs’:
fs/cifs/cifssmb.c:5708: warning: ‘ea_name_len’ may be used uninitialized in
this function

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:21:13 +00:00
Jeff Layton
91d065c473 cifs: fix name parsing in CIFSSMBQAllEAs
The code that matches EA names in CIFSSMBQAllEAs is incorrect. It
uses strncmp to do the comparison with the length limited to the
name_len sent in the response.

Problem: Suppose we're looking for an attribute named "foobar" and
have an attribute before it in the EA list named "foo". The
comparison will succeed since we're only looking at the first 3
characters. Fix this by also comparing the length of the provided
ea_name with the name_len in the response. If they're not equal then
it shouldn't match.

Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:21:09 +00:00
Jeff Layton
998d6fcb24 cifs: don't start signing too early
Sniffing traffic on the wire shows that windows clients send a zeroed
out signature field in a NEGOTIATE request, and send "BSRSPYL" in the
signature field during SESSION_SETUP. Make the cifs client behave the
same way.

It doesn't seem to make much difference in any server that I've tested
against, but it's probably best to follow windows behavior as closely as
possible here.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:21:06 +00:00
Jeff Layton
1f1cff0be0 cifs: trivial: goto out here is unnecessary
...and remove some obsolete comments.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:21:02 +00:00
Jeff Layton
c4d3396b26 cifs: advertise the right receive buffer size to the server
Currently, we mirror the same size back to the server that it sends us.
That makes little sense. Instead we should be sending the server the
maximum buffer size that we can handle -- CIFSMaxBufSize minus the
4 byte RFC1001 header.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-31 21:20:58 +00:00
Linus Torvalds
1d87c28e68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: Cleanup: check return codes of crypto api calls
  CIFS: Fix oops while mounting with prefixpath
  [CIFS] Redundant null check after dereference
  cifs: use cifs_dirent in cifs_save_resume_key
  cifs: use cifs_dirent to replace cifs_get_name_from_search_buf
  cifs: introduce cifs_dirent
  cifs: cleanup cifs_filldir
2011-07-26 11:11:28 -07:00
Shirish Pargaonkar
14cae3243b cifs: Cleanup: check return codes of crypto api calls
Check return codes of crypto api calls and either log an error or log
an error and return from the calling function with error.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 22:12:10 +00:00
Pavel Shilovsky
f5bc1e755d CIFS: Fix oops while mounting with prefixpath
commit fec11dd9a0 caused
a regression when we have already mounted //server/share/a
and want to mount //server/share/a/b.

The problem is that lookup_one_len calls __lookup_hash
with nd pointer as NULL. Then __lookup_hash calls
do_revalidate in the case when dentry exists and we end
up with NULL pointer deference in cifs_d_revalidate:

if (nd->flags & LOOKUP_RCU)
	return -ECHILD;

Fix this by checking nd for NULL.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Shirish Pargaonkar <shirishp@us.ibm.com>
CC: Stable <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 22:06:40 +00:00
Steve French
e010a5ef95 [CIFS] Redundant null check after dereference
Reviewed-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 22:04:32 +00:00
Christoph Hellwig
eaf35b1ea8 cifs: use cifs_dirent in cifs_save_resume_key
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 21:43:14 +00:00
Christoph Hellwig
f16d59b417 cifs: use cifs_dirent to replace cifs_get_name_from_search_buf
This allows us to parse the on the wire structures only once in
cifs_filldir.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 21:40:53 +00:00
Christoph Hellwig
cda0ec6a86 cifs: introduce cifs_dirent
Introduce a generic directory entry structure, and factor the parsing
of the various on the wire structures that can represent one into
a common helper.  Switch cifs_entry_is_dot over to use it as a start.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 21:36:44 +00:00
Christoph Hellwig
9feed6f8fb cifs: cleanup cifs_filldir
Use sensible variable names and formatting and remove some superflous
checks on entry.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-25 21:05:10 +00:00