Commit Graph

389 Commits

Author SHA1 Message Date
Jeff Layton
e28bc5b1fd cifs: add cifs_async_readv
...which will allow cifs to do an asynchronous read call to the server.
The caller will allocate and set up cifs_readdata for each READ_AND_X
call that should be issued on the wire. The pages passed in are added
to the pagecache, but not placed on the LRU list yet (as we need the
page->lru to keep the pages on the list in the readdata).

When cifsd identifies the mid, it will see that there is a special
receive handler for the call, and use that to receive the rest of the
frame. cifs_readv_receive will then marshal up a kvec array with
kmapped pages from the pagecache, which eliminates one copy of the
data. Once the data is received, the pages are added to the LRU list,
set uptodate, and unlocked.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:30:07 -04:00
Jeff Layton
44d22d846f cifs: add a callback function to receive the rest of the frame
In order to handle larger SMBs for readpages and other calls, we want
to be able to read into a preallocated set of buffers. Rather than
changing all of the existing code to preallocate buffers however, we
instead add a receive callback function to the MID.

cifsd will call this function once the mid_q_entry has been identified
in order to receive the rest of the SMB. If the mid can't be identified
or the receive pointer is unset, then the standard 3rd phase receive
function will be called.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:49 -04:00
Jeff Layton
e9097ab489 cifs: break out 3rd receive phase into separate function
Move the entire 3rd phase of the receive codepath into a separate
function in preparation for the addition of a pluggable receive
function.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:40 -04:00
Jeff Layton
c8054ebdb6 cifs: find mid earlier in receive codepath
In order to receive directly into a preallocated buffer, we need to ID
the mid earlier, before the bulk of the response is read. Call the mid
finding routine as soon as we're able to read the mid.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:31 -04:00
Jeff Layton
2a37ef94bb cifs: move buffer pointers into TCP_Server_Info
We have several functions that need to access these pointers. Currently
that's done with a lot of double pointer passing. Instead, move them
into the TCP_Server_Info and simplify the handling.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:23 -04:00
Jeff Layton
ffc00e27aa cifs: eliminate is_multi_rsp parm to find_cifs_mid
Change find_cifs_mid to only return NULL if a mid could not be found.
If we got part of a multi-part T2 response, then coalesce it and still
return the mid. The caller can determine the T2 receive status from
the flags in the mid.

With this change, there is no need to pass a pointer to "length" as
well so just pass by value. If a mid is found, then we can just mark
it as malformed. If one isn't found, then the value of "length" won't
change anyway.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:13 -04:00
Jeff Layton
ea1f4502fc cifs: move mid finding into separate routine
Begin breaking up find_cifs_mid into smaller pieces. The parts that
coalesce T2 responses don't really need to be done under the
GlobalMid_lock anyway. Create a new function that just finds the
mid on the list, and then later takes it off the list if the entire
response has been received.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:29:05 -04:00
Jeff Layton
89482a56a0 cifs: add a third receive phase to cifs_demultiplex_thread
Have the demultiplex thread receive just enough to get to the MID, and
then find it before receiving the rest. Later, we'll use this to swap
in a preallocated receive buffer for some calls.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:28:57 -04:00
Jeff Layton
1041e3f991 cifs: keep a reusable kvec array for receives
Having to continually allocate a new kvec array is expensive. Allocate
one that's big enough, and only reallocate it as needed.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:28:27 -04:00
Jeff Layton
42c4dfc213 cifs: turn read_from_socket into a wrapper around a vectorized version
Eventually we'll want to allow cifsd to read data directly into the
pagecache. In order to do that we'll need a routine that can take a
kvec array and pass that directly to kernel_recvmsg.

Unfortunately though, the kernel's recvmsg routines modify the kvec
array that gets passed in, so we need to use a copy of the kvec array
and refresh that copy on each pass through the loop.

Reviewed-and-Tested-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
2011-10-19 15:28:17 -04:00
Jeff Layton
fe11e4ccb8 cifs: clean up check_rfc1002_header
Rename it for better clarity as to what it does and have the caller pass
in just the single type byte. Turn the if statement into a switch and
optimize it by placing the most common message type at the top. Move the
header length check back into cifs_demultiplex_thread in preparation
for adding a new receive phase and normalize the cFYI messages.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-13 18:44:40 -05:00
Pavel Shilovsky
94443f4340 CIFS: Fix incorrect max RFC1002 write size value
..the length field has only 17 bits.

Cc: <stable@kernel.org>
Acked-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-13 15:20:14 -05:00
Jeff Layton
a52c1eb7ae cifs: simplify read_from_socket
Move the iovec handling entirely into read_from_socket. That simplifies
the code and gets rid of the special handling for header reads. With
this we can also get rid of the "goto incomplete_rcv" label in the main
demultiplex thread function since we can now treat header and non-header
receives the same way.

Also, make it return an int (since we'll never receive enough to worry
about the sign bit anyway), and simply make it return the amount of bytes
read or a negative error code.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2011-10-13 00:05:59 -05:00
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
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
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
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
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
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
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
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
Al Viro
7c97c200e2 cifs: fix the type of cifs_demultiplex_thread()
... and get rid of a bogus typecast, while we are at it; it's not
just that we want a function returning int and not void, but cast
to pointer to function taking void * and returning void would be
(void (*)(void *)) and not (void *)(void *), TYVM...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:39 -04:00
Steve French
ea1be1a3c3 [CIFS] update limit for snprintf in cifs_construct_tcon
In 34c87901e1 "Shrink stack space usage in cifs_construct_tcon" we
change the size of the username name buffer from MAX_USERNAME_SIZE
(256) to 28.  This call to snprintf() needs to be updated as well.
Reported by Dan Carpenter.

Reviewed-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-12 19:14:24 +00:00
Jeff Layton
f484b5d001 cifs: drop spinlock before calling cifs_put_tlink
...as that function can sleep.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-11 18:40:52 +00:00
Jeff Layton
b9bce2e9f9 cifs: fix expand_dfs_referral
Regression introduced in commit 724d9f1cfb.

Prior to that, expand_dfs_referral would regenerate the mount data string
and then call cifs_parse_mount_options to re-parse it (klunky, but it
worked). The above commit moved cifs_parse_mount_options out of cifs_mount,
so the re-parsing of the new mount options no longer occurred. Fix it by
making expand_dfs_referral re-parse the mount options.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-09 21:25:57 +00:00
Jeff Layton
20547490c1 cifs: move bdi_setup_and_register outside of CONFIG_CIFS_DFS_UPCALL
This needs to be done regardless of whether that KConfig option is set
or not.

Reported-by: Sven-Haegar Koch <haegar@sdinet.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-09 20:29:51 +00:00
Jeff Layton
04db79b015 cifs: factor smb_vol allocation out of cifs_setup_volume_info
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-08 03:51:23 +00:00
Jeff Layton
f9e59bcba2 cifs: have cifs_cleanup_volume_info not take a double pointer
...as that makes for a cumbersome interface. Make it take a regular
smb_vol pointer and rely on the caller to zero it out if needed.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-06 20:03:05 +00:00
Jeff Layton
b2a0fa1520 cifs: fix build_unc_path_to_root to account for a prefixpath
Regression introduced by commit f87d39d951.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-06 20:03:05 +00:00
Jeff Layton
677d8537d8 cifs: remove bogus call to cifs_cleanup_volume_info
This call to cifs_cleanup_volume_info is clearly wrong. As soon as it's
called the following call to cifs_get_tcp_session will oops as the
volume_info pointer will then be NULL.

The caller of cifs_mount should clean up this data since it passed it
in. There's no need for us to call this here.

Regression introduced by commit 724d9f1cfb.

Reported-by: Adam Williamson <awilliam@redhat.com>
Cc: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-06 20:03:04 +00:00
Jeff Layton
ee1b3ea9e6 cifs: set socket send and receive timeouts before attempting connect
Benjamin S. reported that he was unable to suspend his machine while
it had a cifs share mounted. The freezer caused this to spew when he
tried it:

-----------------------[snip]------------------
PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ...
Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0):
cifsd         S ffff880127f7b1b0     0  1821      2 0x00800000
 ffff880127f7b1b0 0000000000000046 ffff88005fe008a8 ffff8800ffffffff
 ffff880127cee6b0 0000000000011100 ffff880127737fd8 0000000000004000
 ffff880127737fd8 0000000000011100 ffff880127f7b1b0 ffff880127736010
Call Trace:
 [<ffffffff811e85dd>] ? sk_reset_timer+0xf/0x19
 [<ffffffff8122cf3f>] ? tcp_connect+0x43c/0x445
 [<ffffffff8123374e>] ? tcp_v4_connect+0x40d/0x47f
 [<ffffffff8126ce41>] ? schedule_timeout+0x21/0x1ad
 [<ffffffff8126e358>] ? _raw_spin_lock_bh+0x9/0x1f
 [<ffffffff811e81c7>] ? release_sock+0x19/0xef
 [<ffffffff8123e8be>] ? inet_stream_connect+0x14c/0x24a
 [<ffffffff8104485b>] ? autoremove_wake_function+0x0/0x2a
 [<ffffffffa02ccfe2>] ? ipv4_connect+0x39c/0x3b5 [cifs]
 [<ffffffffa02cd7b7>] ? cifs_reconnect+0x1fc/0x28a [cifs]
 [<ffffffffa02cdbdc>] ? cifs_demultiplex_thread+0x397/0xb9f [cifs]
 [<ffffffff81076afc>] ? perf_event_exit_task+0xb9/0x1bf
 [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs]
 [<ffffffffa02cd845>] ? cifs_demultiplex_thread+0x0/0xb9f [cifs]
 [<ffffffff810444a1>] ? kthread+0x7a/0x82
 [<ffffffff81002d14>] ? kernel_thread_helper+0x4/0x10
 [<ffffffff81044427>] ? kthread+0x0/0x82
 [<ffffffff81002d10>] ? kernel_thread_helper+0x0/0x10

Restarting tasks ... done.
-----------------------[snip]------------------

We do attempt to perform a try_to_freeze in cifs_reconnect, but the
connection attempt itself seems to be taking longer than 20s to time
out. The connect timeout is governed by the socket send and receive
timeouts, so we can shorten that period by setting those timeouts
before attempting the connect instead of after.

Adam Williamson tested the patch and said that it seems to have fixed
suspending on his laptop when a cifs share is mounted.

Reported-by: Benjamin S <da_joind@gmx.net>
Tested-by: Adam Williamson <awilliam@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-07-01 16:15:30 +00:00
Linus Torvalds
804a007f54 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  cifs: propagate errors from cifs_get_root() to mount(2)
  cifs: tidy cifs_do_mount() up a bit
  cifs: more breakage on mount failures
  cifs: close sget() races
  cifs: pull freeing mountdata/dropping nls/freeing cifs_sb into cifs_umount()
  cifs: move cifs_umount() call into ->kill_sb()
  cifs: pull cifs_mount() call up
  sanitize cifs_umount() prototype
  cifs: initialize ->tlink_tree in cifs_setup_cifs_sb()
  cifs: allocate mountdata earlier
  cifs: leak on mount if we share superblock
  cifs: don't pass superblock to cifs_mount()
  cifs: don't leak nls on mount failure
  cifs: double free on mount failure
  take bdi setup/destruction into cifs_mount/cifs_umount

Acked-by: Steve French <smfrench@gmail.com>
2011-06-26 19:39:22 -07:00
Al Viro
d757d71bfc cifs: pull freeing mountdata/dropping nls/freeing cifs_sb into cifs_umount()
all callers of cifs_umount() proceed to do the same thing; pull it into
cifs_umount() itself.

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-24 18:39:42 -04:00
Al Viro
2a9b99516c sanitize cifs_umount() prototype
a) superblock argument is unused
b) it always returns 0

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-24 18:39:42 -04:00
Al Viro
2ced6f6935 cifs: initialize ->tlink_tree in cifs_setup_cifs_sb()
no need to wait until cifs_read_super() and we need it done
by the time cifs_mount() will be called.

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-24 18:39:42 -04:00
Al Viro
2c6292ae4b cifs: don't pass superblock to cifs_mount()
To close sget() races we'll need to be able to set cifs_sb up before
we get the superblock, so we'll want to be able to do cifs_mount()
earlier.  Fortunately, it's easy to do - setting ->s_maxbytes can
be done in cifs_read_super(), ditto for ->s_time_gran and as for
putting MS_POSIXACL into ->s_flags, we can mirror it in ->mnt_cifs_flags
until cifs_read_super() is called.  Kill unused 'devname' argument,
while we are at it...

Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-24 18:39:41 -04:00
Al Viro
dd85446619 take bdi setup/destruction into cifs_mount/cifs_umount
Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-24 18:39:41 -04:00
Jeff Layton
1190f6a067 cifs: fix wsize negotiation to respect max buffer size and active signing (try #4)
Hopefully last version. Base signing check on CAP_UNIX instead of
tcon->unix_ext, also clean up the comments a bit more.

According to Hongwei Sun's blog posting here:

    http://blogs.msdn.com/b/openspecification/archive/2009/04/10/smb-maximum-transmit-buffer-size-and-performance-tuning.aspx

CAP_LARGE_WRITEX is ignored when signing is active. Also, the maximum
size for a write without CAP_LARGE_WRITEX should be the maxBuf that
the server sent in the NEGOTIATE request.

Fix the wsize negotiation to take this into account. While we're at it,
alter the other wsize definitions to use sizeof(WRITE_REQ) to allow for
slightly larger amounts of data to potentially be written per request.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-23 17:54:39 +00:00
Pavel Shilovsky
446b23a758 CIFS: Fix problem with 3.0-rc1 null user mount failure
Figured it out: it was broken by b946845a9d commit - "cifs: cifs_parse_mount_options: do not tokenize mount options in-place". So, as a quick fix I suggest to apply this patch.

[PATCH] CIFS: Fix kfree() with constant string in a null user case

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-22 21:43:56 +00:00
Jeff Layton
8d1bca328b cifs: correctly handle NULL tcon pointer in CIFSTCon
Long ago (in commit 00e485b0), I added some code to handle share-level
passwords in CIFSTCon. That code ignored the fact that it's legit to
pass in a NULL tcon pointer when connecting to the IPC$ share on the
server.

This wasn't really a problem until recently as we only called CIFSTCon
this way when the server returned -EREMOTE. With the introduction of
commit c1508ca2 however, it gets called this way on every mount, causing
an oops when share-level security is in effect.

Fix this by simply treating a NULL tcon pointer as if user-level
security were in effect. I'm not aware of any servers that protect the
IPC$ share with a specific password anyway. Also, add a comment to the
top of CIFSTCon to ensure that we don't make the same mistake again.

Cc: <stable@kernel.org>
Reported-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>
2011-06-13 20:34:34 +00:00
Jeff Layton
7fdbaa1b8d cifs: don't allow cifs_reconnect to exit with NULL socket pointer
It's possible for the following set of events to happen:

cifsd calls cifs_reconnect which reconnects the socket. A userspace
process then calls cifs_negotiate_protocol to handle the NEGOTIATE and
gets a reply. But, while processing the reply, cifsd calls
cifs_reconnect again.  Eventually the GlobalMid_Lock is dropped and the
reply from the earlier NEGOTIATE completes and the tcpStatus is set to
CifsGood. cifs_reconnect then goes through and closes the socket and sets the
pointer to zero, but because the status is now CifsGood, the new socket
is not created and cifs_reconnect exits with the socket pointer set to
NULL.

Fix this by only setting the tcpStatus to CifsGood if the tcpStatus is
CifsNeedNegotiate, and by making sure that generic_ip_connect is always
called at least once in cifs_reconnect.

Note that this is not a perfect fix for this issue. It's still possible
that the NEGOTIATE reply is handled after the socket has been closed and
reconnected. In that case, the socket state will look correct but it no
NEGOTIATE was performed on it be for the wrong socket. In that situation
though the server should just shut down the socket on the next attempted
send, rather than causing the oops that occurs today.

Cc: <stable@kernel.org> # .38.x: fd88ce9: [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood
Reported-and-Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-13 20:34:33 +00:00
Pavel Shilovsky
cd51875d53 CIFS: Fix sparse error
cifs_sb_master_tlink was declared as inline, but without a definition.
Remove the declaration and move the definition up.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-13 20:34:33 +00:00
Jeff Layton
83fb086e0e cifs: trivial: add space in fsc error message
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-08 16:03:29 +00:00
Vasily Averin
957df4535d possible memory corruption in cifs_parse_mount_options()
error path after mountdata check frees uninitialized mountdata_copy

Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-06-06 15:31:29 +00:00