The srv_mutex is used during writeback so cifs should ensure that
allocations done when that mutex is held are done with GFP_NOFS, to
avoid having direct reclaim ending up waiting for the same mutex and
causing a deadlock. This is detected by lockdep with the splat below:
======================================================
WARNING: possible circular locking dependency detected
5.18.0 #70 Not tainted
------------------------------------------------------
kswapd0/49 is trying to acquire lock:
ffff8880195782e0 (&tcp_ses->srv_mutex){+.+.}-{3:3}, at: compound_send_recv
but task is already holding lock:
ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire
kmem_cache_alloc_trace
__request_module
crypto_alg_mod_lookup
crypto_alloc_tfm_node
crypto_alloc_shash
cifs_alloc_hash
smb311_crypto_shash_allocate
smb311_update_preauth_hash
compound_send_recv
cifs_send_recv
SMB2_negotiate
smb2_negotiate
cifs_negotiate_protocol
cifs_get_smb_ses
cifs_mount
cifs_smb3_do_mount
smb3_get_tree
vfs_get_tree
path_mount
__x64_sys_mount
do_syscall_64
entry_SYSCALL_64_after_hwframe
-> #0 (&tcp_ses->srv_mutex){+.+.}-{3:3}:
__lock_acquire
lock_acquire
__mutex_lock
mutex_lock_nested
compound_send_recv
cifs_send_recv
SMB2_write
smb2_sync_write
cifs_write
cifs_writepage_locked
cifs_writepage
shrink_page_list
shrink_lruvec
shrink_node
balance_pgdat
kswapd
kthread
ret_from_fork
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&tcp_ses->srv_mutex);
lock(fs_reclaim);
lock(&tcp_ses->srv_mutex);
*** DEADLOCK ***
1 lock held by kswapd0/49:
#0: ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat
stack backtrace:
CPU: 2 PID: 49 Comm: kswapd0 Not tainted 5.18.0 #70
Call Trace:
<TASK>
dump_stack_lvl
dump_stack
print_circular_bug.cold
check_noncircular
__lock_acquire
lock_acquire
__mutex_lock
mutex_lock_nested
compound_send_recv
cifs_send_recv
SMB2_write
smb2_sync_write
cifs_write
cifs_writepage_locked
cifs_writepage
shrink_page_list
shrink_lruvec
shrink_node
balance_pgdat
kswapd
kthread
ret_from_fork
</TASK>
Fix this by using the memalloc_nofs_save/restore APIs around the places
where the srv_mutex is held. Do this in a wrapper function for the
lock/unlock of the srv_mutex, and rename the srv_mutex to avoid missing
call sites in the conversion.
Note that there is another lockdep warning involving internal crypto
locks, which was masked by this problem and is visible after this fix,
see the discussion in this thread:
https://lore.kernel.org/all/20220523123755.GA13668@axis.com/
Link: https://lore.kernel.org/r/CANT5p=rqcYfYMVHirqvdnnca4Mo+JQSw5Qu12v=kPfpk5yhhmg@mail.gmail.com/
Reported-by: Shyam Prasad N <nspmangalore@gmail.com>
Suggested-by: Lars Persson <larper@axis.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The cifs_demultiplexer_thread should only call cifs_reconnect.
If any other thread wants to trigger a reconnect, they can do
so by updating the server tcpStatus to CifsNeedReconnect.
The last patch attempted to use the same helper function for
both types of threads, but that causes other issues
with lock dependencies.
This patch creates a new helper for non-cifsd threads, that
will indicate to cifsd that the server needs reconnect.
Fixes: 2a05137a05 ("cifs: mark sessions for reconnection in helper function")
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
cifs_mark_tcp_ses_conns_for_reconnect helper function is now
meant to be used by any of the threads to mark a channel
(or all the channels) for reconnect.
Replace all such manual changes to tcpStatus to use this
helper function, which takes care that the right channels,
smb sessions and tcons are marked for reconnect.
Also includes one line minor change
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Help userland apps to identify cifs and smb2 mounts.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Mount will hang if using SMB1 and DFS.
This is because every call to get_next_mid() will, unconditionally,
mark tcpStatus to CifsNeedReconnect before even establishing the
initial connect, because "reconnect" variable was not initialized.
Initializing "reconnect" to false fix this issue.
Fixes: 220c5bc25d87 ("cifs: take cifs_tcp_ses_lock for status checks")
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
While checking/updating status for tcp ses, smb ses or tcon,
we take GlobalMid_Lock. This doesn't make any sense.
Replaced it with cifs_tcp_ses_lock.
Ideally, we should take a spin lock per struct.
But since tcp ses, smb ses and tcon objects won't add up to a lot,
I think there should not be too much contention.
Also, in few other places, these are checked without locking.
Added locking for these.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We use the concept of "binding" when one of the secondary channel
is in the process of connecting/reconnecting to the server. Till this
binding process completes, and the channel is bound to an existing session,
we redirect traffic from other established channels on the binding channel,
effectively blocking all traffic till individual channels get reconnected.
With my last set of commits, we can get rid of this binding serialization.
We now have a bitmap of connection states for each channel. We will use
this bitmap instead for tracking channel status.
Having a bitmap also now enables us to keep the session alive, as long
as even a single channel underneath is alive.
Unfortunately, this also meant that we need to supply the tcp connection
info for the channel during all negotiate and session setup functions.
These changes have resulted in a slightly bigger code churn.
However, I expect perf and robustness improvements in the mchan scenario
after this change.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
strndup(s, strlen(s)) is a highly unidiomatic way to spell strdup(s);
it's *NOT* safer in any way, since strlen() is just as sensitive to
NUL-termination as strdup() is.
strndup() is for situations when you need a copy of a known-sized
substring, not a magic security juju to drive the bad spirits away.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>
Harmonize and change all such variables to 'ctx', where possible.
No changes to actual logic.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
RHBZ 1145308
Some very old server may not support SetPathInfo to adjust the timestamps
of directories. For these servers, try to open the directory and use SetFileInfo.
Minor correction to patch included that was
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Tested-by: Kenneth D'souza <kdsouza@redhat.com>
Use pr_fmt to standardize all logging for fs/cifs.
Some logging output had no CIFS: specific prefix.
Now all output has one of three prefixes:
o CIFS:
o CIFS: VFS:
o Root-CIFS:
Miscellanea:
o Convert printks to pr_<level>
o Neaten macro definitions
o Remove embedded CIFS: prefixes from formats
o Convert "illegal" to "invalid"
o Coalesce formats
o Add missing '\n' format terminations
o Consolidate multiple cifs_dbg continuations into single calls
o More consistent use of upper case first word output logging
o Multiline statement argument alignment and wrapping
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
To rename a file in SMB2 we open it with the DELETE access and do a
special SetInfo on it. If the handle is missing the DELETE bit the
server will fail the SetInfo with STATUS_ACCESS_DENIED.
We currently try to reuse any existing opened handle we have with
cifs_get_writable_path(). That function looks for handles with WRITE
access but doesn't check for DELETE, making rename() fail if it finds
a handle to reuse. Simple reproducer below.
To select handles with the DELETE bit, this patch adds a flag argument
to cifs_get_writable_path() and find_writable_file() and the existing
'bool fsuid_only' argument is converted to a flag.
The cifsFileInfo struct only stores the UNIX open mode but not the
original SMB access flags. Since the DELETE bit is not mapped in that
mode, this patch stores the access mask in cifs_fid on file open,
which is accessible from cifsFileInfo.
Simple reproducer:
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define E(s) perror(s), exit(1)
int main(int argc, char *argv[])
{
int fd, ret;
if (argc != 3) {
fprintf(stderr, "Usage: %s A B\n"
"create&open A in write mode, "
"rename A to B, close A\n", argv[0]);
return 0;
}
fd = openat(AT_FDCWD, argv[1], O_WRONLY|O_CREAT|O_SYNC, 0666);
if (fd == -1) E("openat()");
ret = rename(argv[1], argv[2]);
if (ret) E("rename()");
ret = close(fd);
if (ret) E("close()");
return ret;
}
$ gcc -o bugrename bugrename.c
$ ./bugrename /mnt/a /mnt/b
rename(): Permission denied
Fixes: 8de9e86c67 ("cifs: create a helper to find a writeable handle by path name")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag was missing from
some of the operations.
Change all operations to use the macro cifs_create_options() to
set the backup intent flag if needed.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currenly we doesn't assume that a server may break a lease
from RWH to RW which causes us setting a wrong lease state
on a file and thus mistakenly flushing data and byte-range
locks and purging cached data on the client. This leads to
performance degradation because subsequent IOs go directly
to the server.
Fix this by propagating new lease state and epoch values
to the oplock break handler through cifsFileInfo structure
and removing the use of cifsInodeInfo flags for that. It
allows to avoid some races of several lease/oplock breaks
using those flags in parallel.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
According to MS-CIFS specification MID 0xFFFF should not be used by the
CIFS client, but we actually do. Besides, this has proven to cause races
leading to oops between SendReceive2/cifs_demultiplex_thread. On SMB1,
MID is a 2 byte value easy to reach in CurrentMid which may conflict with
an oplock break notification request coming from server
Signed-off-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
SMB3 ACL support is needed for many use cases now and should not be
ifdeffed out, even for SMB1 (CIFS). Remove the CONFIG_CIFS_ACL
ifdef so ACL support is always built into cifs.ko
Signed-off-by: Steve French <stfrench@microsoft.com>
When using multidialect negotiate (default or specifying vers=3.0 which
allows any smb3 dialect), fix how we check for an existing server session.
Before this fix if you mounted a second time to the same server (e.g. a
different share on the same server) we would only reuse the existing smb
session if a single dialect were requested (e.g. specifying vers=2.1 or vers=3.0
or vers=3.1.1 on the mount command). If a default mount (e.g. not
specifying vers=) is done then would always create a new socket connection
and SMB3 (or SMB3.1.1) session each time we connect to a different share
on the same server rather than reusing the existing one.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Based on 1 normalized pattern(s):
this library is free software you can redistribute it and or modify
it under the terms of the gnu general public license v2 as published
by the free software foundation this library is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu lesser general public license for more details
you should have received a copy of the gnu lesser general public
license along with this library if not write to the free software
foundation inc 59 temple place suite 330 boston ma 02111 1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 2 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.539286961@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Two of the common symlink formats use reparse points
(unlike mfsymlinks and also unlike the SMB1 posix
extensions). This is the first part of the fixes
to allow these reparse points (NFS style and Windows
symlinks) to be resolved properly as symlinks by the
client.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This cleanup removes cifs specific code from SMB2/SMB3 code paths
which is cleaner and easier to maintain as the code to handle
special files is improved. Below is an example creating special files
using 'sfu' mount option over SMB3 to Windows (with this patch)
(Note that to Samba server, support for saving dos attributes
has to be enabled for the SFU mount option to work).
In the future this will also make implementation of creating
special files as reparse points easier (as Windows NFS server does
for example).
root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char
character special file
root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block
block special file
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
When compiling with -Wformat, clang emits the following warnings:
fs/cifs/smb1ops.c:312:20: warning: format specifies type 'unsigned
short' but the argument has type 'unsigned int' [-Wformat]
tgt_total_cnt, total_in_tgt);
^~~~~~~~~~~~
fs/cifs/cifs_dfs_ref.c:289:4: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
ref->flags, ref->server_type);
^~~~~~~~~~
fs/cifs/cifs_dfs_ref.c:289:16: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
ref->flags, ref->server_type);
^~~~~~~~~~~~~~~~
fs/cifs/cifs_dfs_ref.c:291:4: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
ref->ref_flag, ref->path_consumed);
^~~~~~~~~~~~~
fs/cifs/cifs_dfs_ref.c:291:19: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
ref->ref_flag, ref->path_consumed);
^~~~~~~~~~~~~~~~~~
The types of these arguments are unconditionally defined, so this patch
updates the format character to the correct ones for ints and unsigned
ints.
Link: https://github.com/ClangBuiltLinux/linux/issues/378
Signed-off-by: Louis Taylor <louis@kragniz.eu>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Every time after a session reconnect we don't need to account for
credits obtained in previous sessions. Introduce new struct cifs_credits
which contains both credits value and reconnect instance of the
time those credits were taken. Modify a routine that add credits
back to handle the reconnect instance by assuming zero credits
if the reconnect happened after the credits were obtained and
before we decided to add them back due to some errors during sending.
This patch fixes the MTU credits cases. The subsequent patch
will handle non-MTU ones.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch will make use of DFS cache routines where appropriate and
do not always request a new referral from server.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CONFIG_CIFS_STATS should always be enabled as Pavel recently
noted. Simple statistics are not a significant performance hit,
and removing the ifdef simplifies the code slightly.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
With protocol version 2.0 mounts we have seen crashes with corrupt mid
entries. Either the server->pending_mid_q list becomes corrupt with a
cyclic reference in one element or a mid object fetched by the
demultiplexer thread becomes overwritten during use.
Code review identified a race between the demultiplexer thread and the
request issuing thread. The demultiplexer thread seems to be written
with the assumption that it is the sole user of the mid object until
it calls the mid callback which either wakes the issuer task or
deletes the mid.
This assumption is not true because the issuer task can be woken up
earlier by a signal. If the demultiplexer thread has proceeded as far
as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer
thread will happily end up calling cifs_delete_mid while the
demultiplexer thread still is using the mid object.
Inserting a delay in the cifs demultiplexer thread widens the race
window and makes reproduction of the race very easy:
if (server->large_buf)
buf = server->bigbuf;
+ usleep_range(500, 4000);
server->lstrp = jiffies;
To resolve this I think the proper solution involves putting a
reference count on the mid object. This patch makes sure that the
demultiplexer thread holds a reference until it has finished
processing the transaction.
Cc: stable@vger.kernel.org
Signed-off-by: Lars Persson <larper@axis.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This variable is set to 4 for all protocol versions and replaces
the hardcoded constant 4 throughought the code.
This will later be updated to reflect whether a response packet
has a 4 byte length preamble or not once we start removing this
field from the SMB2+ dialects.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
This patch is for preparing upper layer doing SMB read via RDMA write.
When RDMA write is used for SMB read, the returned data length is in
DataRemaining in the response packet. Reading it properly by adding a
parameter to specifiy where the returned data length is.
Add the defition for memory registration to wdata and return the correct
length based on if RDMA write is used.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Downgrade the loglevel for SMB2 to prevent filling the log
with messages if e.g. readdir was interrupted. Also make SMB2
and SMB1 codepaths do the same logging during readdir.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
commit 4fcd1813e6 ("Fix reconnect to not defer smb3 session reconnect
long after socket reconnect") added support for Negotiate requests to
be initiated by echo calls.
To avoid delays in calling echo after a reconnect, I added the patch
introduced by the commit b8c600120f ("Call echo service immediately
after socket reconnect").
This has however caused a regression with cifs shares which do not have
support for echo calls to trigger Negotiate requests. On connections
which need to call Negotiation, the echo calls trigger an error which
triggers a reconnect which in turn triggers another echo call. This
results in a loop which is only broken when an operation is performed on
the cifs share. For an idle share, it can DOS a server.
The patch uses the smb_operation can_echo() for cifs so that it is
called only if connection has been already been setup.
kernel bz: 194531
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Tested-by: Jonathan Liu <net147@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
If the security type specified using a mount option is not supported,
the SMB2 session setup code changes the security type to RawNTLMSSP. We
should instead fail the mount and return an error.
The patch changes the code for SMB2 to make it similar to the code used
for SMB1. Like in SMB1, we now use the global security flags to select
the security method to be used when no security method is specified and
to return an error when the requested auth method is not available.
For SMB2, we also use ntlmv2 as a synonym for nltmssp.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This is a bigger patch, but its size is mostly due to
a single change for how we check for remapping illegal characters
in file names - a lot of repeated, small changes to
the way callers request converting file names.
The final patch in the series does the following:
1) changes default behavior for cifs to be more intuitive.
Currently we do not map by default to seven reserved characters,
ie those valid in POSIX but not in NTFS/CIFS/SMB3/Windows,
unless a mount option (mapchars) is specified. Change this
to by default always map and map using the SFM maping
(like the Mac uses) unless the server negotiates the CIFS Unix
Extensions (like Samba does when mounting with the cifs protocol)
when the remapping of the characters is unnecessary. This should
help SMB3 mounts in particular since Samba will likely be
able to implement this mapping with its new "vfs_fruit" module
as it will be doing for the Mac.
2) if the user specifies the existing "mapchars" mount option then
use the "SFU" (Microsoft Services for Unix, SUA) style mapping of
the seven characters instead.
3) if the user specifies "nomapposix" then disable SFM/MAC style mapping
(so no character remapping would be used unless the user specifies
"mapchars" on mount as well, as above).
4) change all the places in the code that check for the superblock
flag on the mount which is set by mapchars and passed in on all
path based operation and change it to use a small function call
instead to set the mapping type properly (and check for the
mapping type in the cifs unicode functions)
Signed-off-by: Steve French <smfrench@gmail.com>
The "sfu" mount option did not work on SMB2/SMB3 mounts.
With these changes when the "sfu" mount option is passed in
on an smb2/smb2.1/smb3 mount the client can emulate (and
recognize) fifo and device (character and device files).
In addition the "sfu" mount option should not conflict
with "mfsymlinks" (symlink emulation) as we will never
create "sfu" style symlinks, but using "sfu" mount option
will allow us to recognize existing symlinks, created with
Microsoft "Services for Unix" (SFU and SUA).
To enable the "sfu" mount option for SMB2/SMB3 the calling
syntax of the generic cifs/smb2/smb3 sync_read and sync_write
protocol dependent function needed to be changed (we
don't have a file struct in all cases), but this actually
ended up simplifying the code a little.
Signed-off-by: Steve French <smfrench@gmail.com>
Changeset eb85d94bd introduced a problem where if a cifs open
fails during query info of a file we
will still try to close the file (happens with certain types
of reparse points) even though the file handle is not valid.
In addition for SMB2/SMB3 we were not mapping the return code returned
by Windows when trying to open a file (like a Windows NFS symlink)
which is a reparse point.
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
CC: stable <stable@vger.kernel.org> #v3.13+
SMB2 servers indicates the end of a directory search with
STATUS_NO_MORE_FILE error code that is not processed now.
This causes generic/257 xfstest to fail. Fix this by triggering
the end of search by this error code in SMB2_query_directory.
Also when negotiating CIFS protocol we tell the server to close
the search automatically at the end and there is no need to do
it itself. In the case of SMB2 protocol, we need to close it
explicitly - separate close directory checks for different
protocols.
Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
If we negotiate SMB 2.1 and higher version of the protocol and
a server supports large write buffer size, we need to consume 1
credit per 65536 bytes. So, we need to know how many credits
we have and obtain the required number of them before constructing
a writedata structure in writepages and iovec write.
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
If wsize changes on reconnect we need to use new writedata structure
that for retrying.
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Problem reported in Red Hat bz 1040329 for strict writes where we cache
only when we hold oplock and write direct to the server when we don't.
When we receive an oplock break, we first change the oplock value for
the inode in cifsInodeInfo->oplock to indicate that we no longer hold
the oplock before we enqueue a task to flush changes to the backing
device. Once we have completed flushing the changes, we return the
oplock to the server.
There are 2 ways here where we can have data corruption
1) While we flush changes to the backing device as part of the oplock
break, we can have processes write to the file. These writes check for
the oplock, find none and attempt to write directly to the server.
These direct writes made while we are flushing from cache could be
overwritten by data being flushed from the cache causing data
corruption.
2) While a thread runs in cifs_strict_writev, the machine could receive
and process an oplock break after the thread has checked the oplock and
found that it allows us to cache and before we have made changes to the
cache. In that case, we end up with a dirty page in cache when we
shouldn't have any. This will be flushed later and will overwrite all
subsequent writes to the part of the file represented by this page.
Before making any writes to the server, we need to confirm that we are
not in the process of flushing data to the server and if we are, we
should wait until the process is complete before we attempt the write.
We should also wait for existing writes to complete before we process
an oplock break request which changes oplock values.
We add a version specific downgrade_oplock() operation to allow for
differences in the oplock values set for the different smb versions.
Cc: stable@vger.kernel.org
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
When mounting with smb2/smb3 (e.g. vers=2.1) and cifsacl mount option,
it was trying to get the mode by querying the acl over the cifs
rather than smb2 protocol. This patch makes that protocol
independent and makes cifsacl smb2 mounts return a more intuitive
operation not supported error (until we add a worker function
for smb2_get_acl).
Note that a previous patch fixed getxattr/setxattr for the CIFSACL xattr
which would unconditionally call cifs_get_acl and cifs_set_acl (even when
mounted smb2). I made those protocol independent last week (new protocol
version operations "get_acl" and "set_acl" but did not add an
smb2_get_acl and smb2_set_acl yet so those now simply return EOPNOTSUPP
which at least is better than sending cifs requests on smb2 mount)
The previous patches did not fix the one remaining case though ie
mounting with "cifsacl" when getting mode from acl would unconditionally
end up calling "cifs_get_acl_from_fid" even for smb2 - so made that protocol
independent but to make that protocol independent had to make sure that the callers
were passing the protocol independent handle structure (cifs_fid) instead
of cifs specific _u16 network file handle (ie cifs_fid instead of cifs_fid->fid)
Now mount with smb2 and cifsacl mount options will return EOPNOTSUP (instead
of timing out) and a future patch will add smb2 operations (e.g. get_smb2_acl)
to enable this.
Signed-off-by: Steve French <smfrench@gmail.com>
The get/set ACL xattr support for CIFS ACLs attempts to send old
cifs dialect protocol requests even when mounted with SMB2 or later
dialects. Sending cifs requests on an smb2 session causes problems -
the server drops the session due to the illegal request.
This patch makes CIFS ACL operations protocol specific to fix that.
Attempting to query/set CIFS ACLs for SMB2 will now return
EOPNOTSUPP (until we add worker routines for sending query
ACL requests via SMB2) instead of sending invalid (cifs)
requests.
A separate followon patch will be needed to fix cifs_acl_to_fattr
(which takes a cifs specific u16 fid so can't be abstracted
to work with SMB2 until that is changed) and will be needed
to fix mount problems when "cifsacl" is specified on mount
with e.g. vers=2.1
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
CC: Stable <stable@kernel.org>
Changeset 666753c3ef added protocol
operations for get/setxattr to avoid calling cifs operations
on smb2/smb3 mounts for xattr operations and this changeset
adds the calls to cifs specific protocol operations for xattrs
(in order to reenable cifs support for xattrs which was
temporarily disabled by the previous changeset. We do not
have SMB2/SMB3 worker function for setting xattrs yet so
this only enables it for cifs.
CCing stable since without these two small changsets (its
small coreq 666753c3ef is
also needed) calling getfattr/setfattr on smb2/smb3 mounts
causes problems.
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
CC: Stable <stable@kernel.org>
Rename CIFSSMBOpen to CIFS_open and make it take
cifs_open_parms structure as a parm.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
When using posix extensions, dfs shares in the dfs root show up as
symlinks resulting in userland tools such as 'ls' calling readlink() on
these shares. Since these are dfs shares, we end up returning -EREMOTE.
$ ls -l /mnt
ls: cannot read symbolic link /mnt/test: Object is remote
total 0
lrwxrwxrwx. 1 root root 19 Nov 6 09:47 test
With added follow_link() support for dfs shares, when using unix
extensions, we call GET_DFS_REFERRAL to obtain the DFS referral and
return the first node returned.
The dfs share in the dfs root is now displayed in the following manner.
$ ls -l /mnt
total 0
lrwxrwxrwx. 1 root root 19 Nov 6 09:47 test -> \vm140-31\test
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Unix extensions rigth now are only applicable to smb1 operations.
Move the check and subsequent unix extension call to the smb1
specific call to query_symlink() ie. cifs_query_symlink().
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Add a new protocol ops function create_mf_symlink and have
create_mf_symlink() use it.
This patchset moves the MFSymlink operations completely to the
ops structure so that we only use the right protocol versions when
querying or creating MFSymlinks.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Rename open_query_close_cifs_symlink to cifs_query_mf_symlink() to make
the name more consistent with other protocol version specific functions.
We also pass tcon as an argument to the function. This is already
available in the calling functions and we can avoid having to make an
unnecessary lookup.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Vincent Whitchurch
Shyam Prasad N
Jeff Layton
Enzo Matsumiya
Al Viro
Ronnie Sahlberg
Joe Perches
Aurelien Aptel
Amir Goldstein
Pavel Shilovsky
Roberto Bergantinos Corpas
Steve French
Thomas Gleixner
Louis Taylor
Paulo Alcantara
Lars Persson
Long Li
Sachin Prabhu
Nakajima Akira
David Howells
Steve French
Pavel Shilovsky
Pavel Shilovsky