Commit graph

2447 commits

Author SHA1 Message Date
Steve French
aa21d67d7f smb3: on kerberos mount if server doesn't specify auth type use krb5
commit 926674de6705f0f1dbf29a62fd758d0977f535d6 upstream.

Some servers (e.g. Azure) do not include a spnego blob in the SMB3
negotiate protocol response, so on kerberos mounts ("sec=krb5")
we can fail, as we expected the server to list its supported
auth types (OIDs in the spnego blob in the negprot response).
Change this so that on krb5 mounts we default to trying krb5 if the
server doesn't list its supported protocol mechanisms.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
Steve French
ae83508da4 smb3: do not attempt cifs operation in smb3 query info error path
commit 1e77a8c204c9d1b655c61751b8ad0fde22421dbb upstream.

If backupuid mount option is sent, we can incorrectly retry
(on access denied on query info) with a cifs (FindFirst) operation
on an smb3 mount which causes the server to force the session close.

We set backup intent on open so no need for this fallback.

See kernel bugzilla 201435

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
Steve French
39d6c4cdcf smb3: allow stats which track session and share reconnects to be reset
commit 2c887635cd6ab3af619dc2be94e5bf8f2e172b78 upstream.

Currently, "echo 0 > /proc/fs/cifs/Stats" resets all of the stats
except the session and share reconnect counts.  Fix it to
reset those as well.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-21 09:27:35 +01:00
Mark Syms
2297977609 CIFS: handle guest access errors to Windows shares
[ Upstream commit 40920c2bb119fd49ba03e2f97a172171781be442 ]

Commit 1a967d6c9b39c226be1b45f13acd4d8a5ab3dc44 ("correctly to
anonymous authentication for the NTLM(v2) authentication") introduces
a regression in handling errors related to attempting a guest
connection to a Windows share which requires authentication. This
should result in a permission denied error but actually causes the
kernel module to enter a never-ending loop trying to follow a DFS
referal which doesn't exist.

The base cause of this is the failure now occurs later in the process
during tree connect and not at the session setup setup and all errors
in tree connect are interpreted as needing to follow the DFS paths
which isn't in this case correct. So, check the returned error against
EACCES and fail if this is returned error.

Feedback from Aurelien:

  PS> net user guest /activate:no
    PS> mkdir C:\guestshare
      PS> icacls C:\guestshare /grant 'Everyone:(OI)(CI)F'
        PS> new-smbshare -name guestshare -path C:\guestshare -fullaccess Everyone

        I've tested v3.10, v4.4, master, master+your patch using default options
        (empty or no user "NU") and user=abc (U).

        NT_LOGON_FAILURE in session setup: LF
        This is what you seem to have in 3.10.

        NT_ACCESS_DENIED in tree connect to the share: AD
        This is what you get before your infinite loop.

                     |   NU       U
                     --------------------------------
                     3.10         |   LF       LF
                     4.4          |   LF       LF
                     master       |   AD       LF
                     master+patch |   AD       LF

                     No infinite DFS loop :(
                     All these issues result in mount failing very fast with permission denied.

                     I guess it could be from either the Windows version or the share/folder
                     ACL. A deeper analysis of the packets might reveal more.

                     In any case I did not notice any issues for on a basic DFS setup with
                     the patch so I don't think it introduced any regressions, which is
                     probably all that matters. It still bothers me a little I couldn't hit
                     the bug.

                     I've included kernel output w/ debugging output and network capture of
                     my tests if anyone want to have a look at it. (master+patch = ml-guestfix).

Signed-off-by: Mark Syms <mark.syms@citrix.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Tested-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-10 07:41:37 -08:00
Aurelien Aptel
ec2a4f06e3 smb2: fix missing files in root share directory listing
commit 0595751f267994c3c7027377058e4185b3a28e75 upstream.

When mounting a Windows share that is the root of a drive (eg. C$)
the server does not return . and .. directory entries. This results in
the smb2 code path erroneously skipping the 2 first entries.

Pseudo-code of the readdir() code path:

cifs_readdir(struct file, struct dir_context)
    initiate_cifs_search            <-- if no reponse cached yet
        server->ops->query_dir_first

    dir_emit_dots
        dir_emit                    <-- adds "." and ".." if we're at pos=0

    find_cifs_entry
        initiate_cifs_search        <-- if pos < start of current response
                                         (restart search)
        server->ops->query_dir_next <-- if pos > end of current response
                                         (fetch next search res)

    for(...)                        <-- loops over cur response entries
                                          starting at pos
        cifs_filldir                <-- skip . and .., emit entry
            cifs_fill_dirent
            dir_emit
	pos++

A) dir_emit_dots() always adds . & ..
   and sets the current dir pos to 2 (0 and 1 are done).

Therefore we always want the index_to_find to be 2 regardless of if
the response has . and ..

B) smb1 code initializes index_of_last_entry with a +2 offset

  in cifssmb.c CIFSFindFirst():
		psrch_inf->index_of_last_entry = 2 /* skip . and .. */ +
			psrch_inf->entries_in_buffer;

Later in find_cifs_entry() we want to find the next dir entry at pos=2
as a result of (A)

	first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
					cfile->srch_inf.entries_in_buffer;

This var is the dir pos that the first entry in the buffer will
have therefore it must be 2 in the first call.

If we don't offset index_of_last_entry by 2 (like in (B)),
first_entry_in_buffer=0 but we were instructed to get pos=2 so this
code in find_cifs_entry() skips the 2 first which is ok for non-root
shares, as it skips . and .. from the response but is not ok for root
shares where the 2 first are actual files

		pos_in_buf = index_to_find - first_entry_in_buffer;
                // pos_in_buf=2
		// we skip 2 first response entries :(
		for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
			/* go entry by entry figuring out which is first */
			cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
						cfile->srch_inf.info_level);
		}

C) cifs_filldir() skips . and .. so we can safely ignore them for now.

Sample program:

int main(int argc, char **argv)
{
	const char *path = argc >= 2 ? argv[1] : ".";
	DIR *dh;
	struct dirent *de;

	printf("listing path <%s>\n", path);
	dh = opendir(path);
	if (!dh) {
		printf("opendir error %d\n", errno);
		return 1;
	}

	while (1) {
		de = readdir(dh);
		if (!de) {
			if (errno) {
				printf("readdir error %d\n", errno);
				return 1;
			}
			printf("end of listing\n");
			break;
		}
		printf("off=%lu <%s>\n", de->d_off, de->d_name);
	}

	return 0;
}

Before the fix with SMB1 on root shares:

<.>            off=1
<..>           off=2
<$Recycle.Bin> off=3
<bootmgr>      off=4

and on non-root shares:

<.>    off=1
<..>   off=4  <-- after adding .., the offsets jumps to +2 because
<2536> off=5       we skipped . and .. from response buffer (C)
<411>  off=6       but still incremented pos
<file> off=7
<fsx>  off=8

Therefore the fix for smb2 is to mimic smb1 behaviour and offset the
index_of_last_entry by 2.

Test results comparing smb1 and smb2 before/after the fix on root
share, non-root shares and on large directories (ie. multi-response
dir listing):

PRE FIX
=======
pre-1-root VS pre-2-root:
        ERR pre-2-root is missing [bootmgr, $Recycle.Bin]
pre-1-nonroot VS pre-2-nonroot:
        OK~ same files, same order, different offsets
pre-1-nonroot-large VS pre-2-nonroot-large:
        OK~ same files, same order, different offsets

POST FIX
========
post-1-root VS post-2-root:
        OK same files, same order, same offsets
post-1-nonroot VS post-2-nonroot:
        OK same files, same order, same offsets
post-1-nonroot-large VS post-2-nonroot-large:
        OK same files, same order, same offsets

REGRESSION?
===========
pre-1-root VS post-1-root:
        OK same files, same order, same offsets
pre-1-nonroot VS post-1-nonroot:
        OK same files, same order, same offsets

BugLink: https://bugzilla.samba.org/show_bug.cgi?id=13107
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Paulo Alcantara <palcantara@suse.deR>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:13 +02:00
Dan Carpenter
cd65a43f4d cifs: read overflow in is_valid_oplock_break()
[ Upstream commit 097f5863b1a0c9901f180bbd56ae7d630655faaa ]

We need to verify that the "data_offset" is within bounds.

Reported-by: Dr Silvio Cesare of InfoSect <silvio.cesare@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:12 +02:00
Stephen Rothwell
8c47defad8 fs/cifs: suppress a string overflow warning
[ Upstream commit bcfb84a996f6fa90b5e6e2954b2accb7a4711097 ]

A powerpc build of cifs with gcc v8.2.0 produces this warning:

fs/cifs/cifssmb.c: In function ‘CIFSSMBNegotiate’:
fs/cifs/cifssmb.c:605:3: warning: ‘strncpy’ writing 16 bytes into a region of size 1 overflows the destination [-Wstringop-overflow=]
   strncpy(pSMB->DialectsArray+count, protocols[i].name, 16);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Since we are already doing a strlen() on the source, change the strncpy
to a memcpy().

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:12 +02:00
Jon Kuhn
2b2ccb29f3 fs/cifs: don't translate SFM_SLASH (U+F026) to backslash
[ Upstream commit c15e3f19a6d5c89b1209dc94b40e568177cb0921 ]

When a Mac client saves an item containing a backslash to a file server
the backslash is represented in the CIFS/SMB protocol as as U+F026.
Before this change, listing a directory containing an item with a
backslash in its name will return that item with the backslash
represented with a true backslash character (U+005C) because
convert_sfm_character mapped U+F026 to U+005C when interpretting the
CIFS/SMB protocol response.  However, attempting to open or stat the
path using a true backslash will result in an error because
convert_to_sfm_char does not map U+005C back to U+F026 causing the
CIFS/SMB request to be made with the backslash represented as U+005C.

This change simply prevents the U+F026 to U+005C conversion from
happenning.  This is analogous to how the code does not do any
translation of UNI_SLASH (U+F000).

Signed-off-by: Jon Kuhn <jkuhn@barracuda.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10 08:52:11 +02:00
Dan Carpenter
74fb46864f CIFS: fix wrapping bugs in num_entries()
commit 56446f218af1133c802dad8e9e116f07f381846c upstream.

The problem is that "entryptr + next_offset" and "entryptr + len + size"
can wrap.  I ended up changing the type of "entryptr" because it makes
the math easier when we don't have to do so much casting.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:35:08 +02:00
Dan Carpenter
2d3631960d cifs: prevent integer overflow in nxt_dir_entry()
commit 8ad8aa353524d89fa2e09522f3078166ff78ec42 upstream.

The "old_entry + le32_to_cpu(pDirInfo->NextEntryOffset)" can wrap
around so I have added a check for integer overflow.

Reported-by: Dr Silvio Cesare of InfoSect <silvio.cesare@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-26 08:35:08 +02:00
Steve French
a9997f8873 SMB3: Number of requests sent should be displayed for SMB3 not just CIFS
[ Upstream commit 289131e1f1e6ad8c661ec05e176b8f0915672059 ]

For SMB2/SMB3 the number of requests sent was not displayed
in /proc/fs/cifs/Stats unless CONFIG_CIFS_STATS2 was
enabled (only number of failed requests displayed). As
with earlier dialects, we should be displaying these
counters if CONFIG_CIFS_STATS is enabled. They
are important for debugging.

e.g. when you cat /proc/fs/cifs/Stats (before the patch)
Resources in use
CIFS Session: 1
Share (unique mount targets): 2
SMB Request/Response Buffer: 1 Pool size: 5
SMB Small Req/Resp Buffer: 1 Pool size: 30
Operations (MIDs): 0

0 session 0 share reconnects
Total vfs operations: 690 maximum at one time: 2

1) \\localhost\test
SMBs: 975
Negotiates: 0 sent 0 failed
SessionSetups: 0 sent 0 failed
Logoffs: 0 sent 0 failed
TreeConnects: 0 sent 0 failed
TreeDisconnects: 0 sent 0 failed
Creates: 0 sent 2 failed
Closes: 0 sent 0 failed
Flushes: 0 sent 0 failed
Reads: 0 sent 0 failed
Writes: 0 sent 0 failed
Locks: 0 sent 0 failed
IOCTLs: 0 sent 1 failed
Cancels: 0 sent 0 failed
Echos: 0 sent 0 failed
QueryDirectories: 0 sent 63 failed

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:40:39 +02:00
Steve French
d6773f4061 smb3: fix reset of bytes read and written stats
[ Upstream commit c281bc0c7412308c7ec0888904f7c99353da4796 ]

echo 0 > /proc/fs/cifs/Stats is supposed to reset the stats
but there were four (see example below) that were not reset
(bytes read and witten, total vfs ops and max ops
at one time).

...
0 session 0 share reconnects
Total vfs operations: 100 maximum at one time: 2

1) \\localhost\test
SMBs: 0
Bytes read: 502092  Bytes written: 31457286
TreeConnects: 0 total 0 failed
TreeDisconnects: 0 total 0 failed
...

This patch fixes cifs_stats_proc_write to properly reset
those four.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:40:39 +02:00
Ronnie Sahlberg
d98ec8a9e2 cifs: check if SMB2 PDU size has been padded and suppress the warning
[ Upstream commit e6c47dd0da1e3a484e778046fc10da0b20606a86 ]

Some SMB2/3 servers, Win2016 but possibly others too, adds padding
not only between PDUs in a compound but also to the final PDU.
This padding extends the PDU to a multiple of 8 bytes.

Check if the unexpected length looks like this might be the case
and avoid triggering the log messages for :

  "SMB2 server sent bad RFC1001 len %d not %d\n"

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-15 09:40:37 +02:00
Steve French
951461680e smb3: don't request leases in symlink creation and query
commit 22783155f4bf956c346a81624ec9258930a6fe06 upstream.

Fixes problem pointed out by Pavel in discussions about commit
729c0c9dd55204f0c9a823ac8a7bfa83d36c7e78

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org> # 3.18.x+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:18:37 +02:00
Steve French
ff3bb182bc smb3: Do not send SMB3 SET_INFO if nothing changed
commit fd09b7d3b352105f08b8e02f7afecf7e816380ef upstream.

An earlier commit had a typo which prevented the
optimization from working:

commit 18dd8e1a65dd ("Do not send SMB3 SET_INFO request if nothing is changing")

Thank you to Metze for noticing this.  Also clear a
reserved field in the FILE_BASIC_INFO struct we send
that should be zero (all the other fields in that
struct were set or cleared explicitly already in
cifs_set_file_info).

Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org> # 4.9.x+
Reported-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:18:37 +02:00
Nicholas Mc Guire
0e28220672 cifs: check kmalloc before use
commit 126c97f4d0d1b5b956e8b0740c81a2b2a2ae548c upstream.

The kmalloc was not being checked - if it fails issue a warning
and return -ENOMEM to the caller.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: b8da344b74c8 ("cifs: dynamic allocation of ntlmssp blob")
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
cc: Stable <stable@vger.kernel.org>`
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:18:37 +02:00
Steve French
58d141a9ad cifs: add missing debug entries for kconfig options
commit 950132afd59385caf6e2b84e5235d069fa10681d upstream.

/proc/fs/cifs/DebugData displays the features (Kconfig options)
used to build cifs.ko but it was missing some, and needed comma
separator.  These can be useful in debugging certain problems
so we know which optional features were enabled in the user's build.
Also clarify them, by making them more closely match the
corresponding CONFIG_CIFS_* parm.

Old format:
Features: dfs fscache posix spnego xattr acl

New format:
Features: DFS,FSCACHE,SMB_DIRECT,STATS,DEBUG2,ALLOW_INSECURE_LEGACY,CIFS_POSIX,UPCALL(SPNEGO),XATTR,ACL

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-05 09:18:37 +02:00
Paulo Alcantara
6ee6f1787e cifs: Fix infinite loop when using hard mount option
commit 7ffbe65578b44fafdef577a360eb0583929f7c6e upstream.

For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.

So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.

Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().

Here's an example of how to trigger that:

$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard

(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511

$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511  0.0  0.0  12892  1008 pts/0    S    12:24   0:00 stat -f
/mnt/test

$ kill -9 2511

(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511 83.2  0.0  12892  1008 pts/0    R    12:24  30:01 stat -f
/mnt/test

By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.

Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-11 16:03:48 +02:00
Arnd Bergmann
9480368828 cifs: silence compiler warnings showing up with gcc-8.0.0
[ Upstream commit ade7db991b47ab3016a414468164f4966bd08202 ]

This bug was fixed before, but came up again with the latest
compiler in another function:

fs/cifs/cifssmb.c: In function 'CIFSSMBSetEA':
fs/cifs/cifssmb.c:6362:3: error: 'strncpy' offset 8 is out of the bounds [0, 4] [-Werror=array-bounds]
   strncpy(parm_data->list[0].name, ea_name, name_len);

Let's apply the same fix that was used for the other instances.

Fixes: b2a3ad9ca5 ("cifs: silence compiler warnings showing up with gcc-4.7.0")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:48:56 +02:00
Steve French
5f3a3e86be cifs: do not allow creating sockets except with SMB1 posix exensions
commit 1d0cffa674cfa7d185a302c8c6850fc50b893bed upstream.

RHBZ: 1453123

Since at least the 3.10 kernel and likely a lot earlier we have
not been able to create unix domain sockets in a cifs share
when mounted using the SFU mount option (except when mounted
with the cifs unix extensions to Samba e.g.)
Trying to create a socket, for example using the af_unix command from
xfstests will cause :
BUG: unable to handle kernel NULL pointer dereference at 00000000
00000040

Since no one uses or depends on being able to create unix domains sockets
on a cifs share the easiest fix to stop this vulnerability is to simply
not allow creation of any other special files than char or block devices
when sfu is used.

Added update to Ronnie's patch to handle a tcon link leak, and
to address a buf leak noticed by Gustavo and Colin.

Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
CC:  Colin Ian King <colin.king@canonical.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29 07:50:01 +02:00
Christophe JAILLET
e38311ff9e SMB2: Fix share type handling
[ Upstream commit cd1230070ae1c12fd34cf6a557bfa81bf9311009 ]

In fs/cifs/smb2pdu.h, we have:
#define SMB2_SHARE_TYPE_DISK    0x01
#define SMB2_SHARE_TYPE_PIPE    0x02
#define SMB2_SHARE_TYPE_PRINT   0x03

Knowing that, with the current code, the SMB2_SHARE_TYPE_PRINT case can
never trigger and printer share would be interpreted as disk share.

So, test the ShareType value for equality instead.

Fixes: faaf946a7d ("CIFS: Add tree connect/disconnect capability for SMB2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:50:04 +02:00
Rabin Vincent
407078971b CIFS: silence lockdep splat in cifs_relock_file()
[ Upstream commit 560d388950ceda5e7c7cdef7f3d9a8ff297bbf9d ]

cifs_relock_file() can perform a down_write() on the inode's lock_sem even
though it was already performed in cifs_strict_readv().  Lockdep complains
about this.  AFAICS, there is no problem here, and lockdep just needs to be
told that this nesting is OK.

 =============================================
 [ INFO: possible recursive locking detected ]
 4.11.0+ #20 Not tainted
 ---------------------------------------------
 cat/701 is trying to acquire lock:
  (&cifsi->lock_sem){++++.+}, at: cifs_reopen_file+0x7a7/0xc00

 but task is already holding lock:
  (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&cifsi->lock_sem);
   lock(&cifsi->lock_sem);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 1 lock held by cat/701:
  #0:  (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310

 stack backtrace:
 CPU: 0 PID: 701 Comm: cat Not tainted 4.11.0+ #20
 Call Trace:
  dump_stack+0x85/0xc2
  __lock_acquire+0x17dd/0x2260
  ? trace_hardirqs_on_thunk+0x1a/0x1c
  ? preempt_schedule_irq+0x6b/0x80
  lock_acquire+0xcc/0x260
  ? lock_acquire+0xcc/0x260
  ? cifs_reopen_file+0x7a7/0xc00
  down_read+0x2d/0x70
  ? cifs_reopen_file+0x7a7/0xc00
  cifs_reopen_file+0x7a7/0xc00
  ? printk+0x43/0x4b
  cifs_readpage_worker+0x327/0x8a0
  cifs_readpage+0x8c/0x2a0
  generic_file_read_iter+0x692/0xd00
  cifs_strict_readv+0x29f/0x310
  generic_file_splice_read+0x11c/0x1c0
  do_splice_to+0xa5/0xc0
  splice_direct_to_actor+0xfa/0x350
  ? generic_pipe_buf_nosteal+0x10/0x10
  do_splice_direct+0xb5/0xe0
  do_sendfile+0x278/0x3a0
  SyS_sendfile64+0xc4/0xe0
  entry_SYSCALL_64_fastpath+0x1f/0xbe

Signed-off-by: Rabin Vincent <rabinv@axis.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13 19:50:03 +02:00
Dan Carpenter
8a58463396 cifs: small underflow in cnvrtDosUnixTm()
[ Upstream commit 564277eceeca01e02b1ef3e141cfb939184601b4 ]

January is month 1.  There is no zero-th month.  If someone passes a
zero month then it means we read from one space before the start of the
total_days_of_prev_months[] array.

We may as well also be strict about days as well.

Fixes: 1bd5bbcb65 ("[CIFS] Legacy time handling for Win9x and OS/2 part 1")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 10:58:46 +01:00
Pavel Shilovsky
26dc7476ef CIFS: Enable encryption during session setup phase
commit cabfb3680f78981d26c078a26e5c748531257ebb upstream.

In order to allow encryption on SMB connection we need to exchange
a session key and generate encryption and decryption keys.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 10:58:40 +01:00
Steve French
0a53587ac6 SMB3: Validate negotiate request must always be signed
commit 4587eee04e2ac7ac3ac9fa2bc164fb6e548f99cd upstream.

According to MS-SMB2 3.2.55 validate_negotiate request must
always be signed. Some Windows can fail the request if you send it unsigned

See kernel bugzilla bug 197311

CC: Stable <stable@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-24 10:58:39 +01:00
Aurelien Aptel
f260cb7751 CIFS: zero sensitive data when freeing
commit 97f4b7276b829a8927ac903a119bef2f963ccc58 upstream.

also replaces memset()+kfree() by kzfree().

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:09:39 +01:00
Daniel N Pettersson
aa8c1051ab cifs: Fix autonegotiate security settings mismatch
commit 9aca7e454415f7878b28524e76bebe1170911a88 upstream.

Autonegotiation gives a security settings mismatch error if the SMB
server selects an SMBv3 dialect that isn't SMB3.02. The exact error is
"protocol revalidation - security settings mismatch".
This can be tested using Samba v4.2 or by setting the global Samba
setting max protocol = SMB3_00.

The check that fails in smb3_validate_negotiate is the dialect
verification of the negotiate info response. This is because it tries
to verify against the protocol_id in the global smbdefault_values. The
protocol_id in smbdefault_values is SMB3.02.
In SMB2_negotiate the protocol_id in smbdefault_values isn't updated,
it is global so it probably shouldn't be, but server->dialect is.

This patch changes the check in smb3_validate_negotiate to use
server->dialect instead of server->vals->protocol_id. The patch works
with autonegotiate and when using a specific version in the vers mount
option.

Signed-off-by: Daniel N Pettersson <danielnp@axis.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:09:39 +01:00
Matthew Wilcox
e343f5fd73 cifs: Fix missing put_xid in cifs_file_strict_mmap
commit f04a703c3d613845ae3141bfaf223489de8ab3eb upstream.

If cifs_zap_mapping() returned an error, we would return without putting
the xid that we got earlier.  Restructure cifs_file_strict_mmap() and
cifs_file_mmap() to be more similar to each other and have a single
point of return that always puts the xid.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:09:39 +01:00
Ronnie Sahlberg
d304c9169b cifs: check MaxPathNameComponentLength != 0 before using it
commit f74bc7c6679200a4a83156bb89cbf6c229fe8ec0 upstream.

And fix tcon leak in error path.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: David Disseldorp <ddiss@samba.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:06:27 +01:00
Pavel Shilovsky
f2bb4bcc04 CIFS: Reconnect expired SMB sessions
commit 511c54a2f69195b28afb9dd119f03787b1625bb4 upstream.

According to the MS-SMB2 spec (3.2.5.1.6) once the client receives
STATUS_NETWORK_SESSION_EXPIRED error code from a server it should
reconnect the current SMB session. Currently the client doesn't do
that. This can result in subsequent client requests failing by
the server. The patch adds an additional logic to the demultiplex
thread to identify expired sessions and reconnect them.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-18 09:20:40 +02:00
Steve French
3bb7084cc0 SMB3: Don't ignore O_SYNC/O_DSYNC and O_DIRECT flags
commit 1013e760d10e614dc10b5624ce9fc41563ba2e65 upstream.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:41:45 +02:00
Steve French
02ef29f9cb SMB: Validate negotiate (to protect against downgrade) even if signing off
commit 0603c96f3af50e2f9299fa410c224ab1d465e0f9 upstream.

As long as signing is supported (ie not a guest user connection) and
connection is SMB3 or SMB3.02, then validate negotiate (protect
against man in the middle downgrade attacks).  We had been doing this
only when signing was required, not when signing was just enabled,
but this more closely matches recommended SMB3 behavior and is
better security.  Suggested by Metze.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Acked-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:41:45 +02:00
Steve French
c096b31f9d Fix SMB3.1.1 guest authentication to Samba
commit 23586b66d84ba3184b8820277f3fc42761640f87 upstream.

Samba rejects SMB3.1.1 dialect (vers=3.1.1) negotiate requests from
the kernel client due to the two byte pad at the end of the negotiate
contexts.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:41:45 +02:00
Shu Wang
fcc949a488 cifs: release auth_key.response for reconnect.
commit f5c4ba816315d3b813af16f5571f86c8d4e897bd upstream.

There is a race that cause cifs reconnect in cifs_mount,
- cifs_mount
  - cifs_get_tcp_session
    - [ start thread cifs_demultiplex_thread
      - cifs_read_from_socket: -ECONNABORTED
        - DELAY_WORK smb2_reconnect_server ]
  - cifs_setup_session
  - [ smb2_reconnect_server ]

auth_key.response was allocated in cifs_setup_session, and
will release when the session destoried. So when session re-
connect, auth_key.response should be check and released.

Tested with my system:
CIFS VFS: Free previous auth_key.response = ffff8800320bbf80

A simple auth_key.response allocation call trace:
- cifs_setup_session
- SMB2_sess_setup
- SMB2_sess_auth_rawntlmssp_authenticate
- build_ntlmssp_auth_blob
- setup_ntlmv2_rsp

Signed-off-by: Shu Wang <shuwang@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:41:44 +02:00
Steve French
5f08f0aebf CIFS: remove endian related sparse warning
commit 6e3c1529c39e92ed64ca41d53abadabbaa1d5393 upstream.

Recent patch had an endian warning ie
cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup()

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-07 08:34:09 +02:00
Pavel Shilovsky
e596cc1454 CIFS: Fix maximum SMB2 header size
commit 9e37b1784f2be9397a903307574ee565bbadfd75 upstream.

Currently the maximum size of SMB2/3 header is set incorrectly which
leads to hanging of directory listing operations on encrypted SMB3
connections. Fix this by setting the maximum size to 170 bytes that
is calculated as RFC1002 length field size (4) + transform header
size (52) + SMB2 header size (64) + create response size (56).

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-07 08:34:09 +02:00
Ronnie Sahlberg
e6066962ca cifs: return ENAMETOOLONG for overlong names in cifs_open()/cifs_lookup()
commit d3edede29f74d335f81d95a4588f5f136a9f7dcf upstream.

Add checking for the path component length and verify it is <= the maximum
that the server advertizes via FileFsAttributeInformation.

With this patch cifs.ko will now return ENAMETOOLONG instead of ENOENT
when users to access an overlong path.

To test this, try to cd into a (non-existing) directory on a CIFS share
that has a too long name:
cd /mnt/aaaaaaaaaaaaaaa...

and it now should show a good error message from the shell:
bash: cd: /mnt/aaaaaaaaaaaaaaaa...aaaaaa: File name too long

rh bz 1153996

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30 10:19:25 +02:00
Sachin Prabhu
210b41b497 cifs: Fix df output for users with quota limits
commit 42bec214d8bd432be6d32a1acb0a9079ecd4d142 upstream.

The df for a SMB2 share triggers a GetInfo call for
FS_FULL_SIZE_INFORMATION. The values returned are used to populate
struct statfs.

The problem is that none of the information returned by the call
contains the total blocks available on the filesystem. Instead we use
the blocks available to the user ie. quota limitation when filling out
statfs.f_blocks. The information returned does contain Actual free units
on the filesystem and is used to populate statfs.f_bfree. For users with
quota enabled, it can lead to situations where the total free space
reported is more than the total blocks on the system ending up with df
reports like the following

 # df -h /mnt/a
Filesystem         Size  Used Avail Use% Mounted on
//192.168.22.10/a  2.5G -2.3G  2.5G    - /mnt/a

To fix this problem, we instead populate both statfs.f_bfree with the
same value as statfs.f_bavail ie. CallerAvailableAllocationUnits. This
is similar to what is done already in the code for cifs and df now
reports the quota information for the user used to mount the share.

 # df --si /mnt/a
Filesystem         Size  Used Avail Use% Mounted on
//192.168.22.10/a  2.7G  101M  2.6G   4% /mnt/a

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pierguido Lambri <plambri@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30 10:19:25 +02:00
Pavel Shilovsky
63ba840a53 CIFS: Improve readdir verbosity
commit dcd87838c06f05ab7650b249ebf0d5b57ae63e1e upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-29 12:48:51 +02:00
Sachin Prabhu
2ba464a4b7 Call echo service immediately after socket reconnect
commit b8c600120fc87d53642476f48c8055b38d6e14c7 upstream.

Commit 4fcd1813e640 ("Fix reconnect to not defer smb3 session reconnect
long after socket reconnect") changes the behaviour of the SMB2 echo
service and causes it to renegotiate after a socket reconnect. However
under default settings, the echo service could take up to 120 seconds to
be scheduled.

The patch forces the echo service to be called immediately resulting a
negotiate call being made immediately on reconnect.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17 06:39:35 +02:00
Björn Jacke
9f4ba9062c CIFS: add misssing SFM mapping for doublequote
commit 85435d7a15294f9f7ef23469e6aaf7c5dfcc54f0 upstream.

SFM is mapping doublequote to 0xF020

Without this patch creating files with doublequote fails to Windows/Mac

Signed-off-by: Bjoern Jacke <bjacke@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:01 +02:00
David Disseldorp
9a40506699 cifs: fix CIFS_IOC_GET_MNT_INFO oops
commit d8a6e505d6bba2250852fbc1c1c86fe68aaf9af3 upstream.

An open directory may have a NULL private_data pointer prior to readdir.

Fixes: 0de1f4c6f6 ("Add way to query server fs info for smb3")
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:01 +02:00
Björn Jacke
a8900a64ea CIFS: fix mapping of SFM_SPACE and SFM_PERIOD
commit b704e70b7cf48f9b67c07d585168e102dfa30bb4 upstream.

- trailing space maps to 0xF028
- trailing period maps to 0xF029

This fix corrects the mapping of file names which have a trailing character
that would otherwise be illegal (period or space) but is allowed by POSIX.

Signed-off-by: Bjoern Jacke <bjacke@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:01 +02:00
Steve French
b85fa4129e SMB3: Work around mount failure when using SMB3 dialect to Macs
commit 7db0a6efdc3e990cdfd4b24820d010e9eb7890ad upstream.

Macs send the maximum buffer size in response on ioctl to validate
negotiate security information, which causes us to fail the mount
as the response buffer is larger than the expected response.

Changed ioctl response processing to allow for padding of validate
negotiate ioctl response and limit the maximum response size to
maximum buffer size.

Signed-off-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:01 +02:00
Steve French
89d23005fd Set unicode flag on cifs echo request to avoid Mac error
commit 26c9cb668c7fbf9830516b75d8bee70b699ed449 upstream.

Mac requires the unicode flag to be set for cifs, even for the smb
echo request (which doesn't have strings).

Without this Mac rejects the periodic echo requests (when mounting
with cifs) that we use to check if server is down

Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:27:01 +02:00
Sachin Prabhu
6c106b55eb Handle mismatched open calls
commit 38bd49064a1ecb67baad33598e3d824448ab11ec upstream.

A signal can interrupt a SendReceive call which result in incoming
responses to the call being ignored. This is a problem for calls such as
open which results in the successful response being ignored. This
results in an open file resource on the server.

The patch looks into responses which were cancelled after being sent and
in case of successful open closes the open fids.

For this patch, the check is only done in SendReceive2()

RH-bz: 1403319

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-08 07:46:01 +02:00
Germano Percossi
859d615b5b CIFS: remove bad_network_name flag
commit a0918f1ce6a43ac980b42b300ec443c154970979 upstream.

STATUS_BAD_NETWORK_NAME can be received during node failover,
causing the flag to be set and making the reconnect thread
always unsuccessful, thereafter.

Once the only place where it is set is removed, the remaining
bits are rendered moot.

Removing it does not prevent "mount" from failing when a non
existent share is passed.

What happens when the share really ceases to exist while the
share is mounted is undefined now as much as it was before.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-27 09:09:32 +02:00
Sachin Prabhu
f8fe51c865 cifs: Do not send echoes before Negotiate is complete
commit 62a6cfddcc0a5313e7da3e8311ba16226fe0ac10 upstream.

commit 4fcd1813e640 ("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 b8c600120fc8 ("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>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-27 09:09:31 +02:00
Germano Percossi
f0899d0e1e CIFS: store results of cifs_reopen_file to avoid infinite wait
commit 1fa839b4986d648b907d117275869a0e46c324b9 upstream.

This fixes Continuous Availability when errors during
file reopen are encountered.

cifs_user_readv and cifs_user_writev would wait for ever if
results of cifs_reopen_file are not stored and for later inspection.

In fact, results are checked and, in case of errors, a chain
of function calls leading to reads and writes to be scheduled in
a separate thread is skipped.
These threads will wake up the corresponding waiters once reads
and writes are done.

However, given the return value is not stored, when rc is checked
for errors a previous one (always zero) is inspected instead.
This leads to pending reads/writes added to the list, making
cifs_user_readv and cifs_user_writev wait for ever.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-21 09:30:05 +02:00
Jan-Marek Glogowski
5a69c2b268 Reset TreeId to zero on SMB2 TREE_CONNECT
commit 806a28efe9b78ffae5e2757e1ee924b8e50c08ab upstream.

Currently the cifs module breaks the CIFS specs on reconnect as
described in http://msdn.microsoft.com/en-us/library/cc246529.aspx:

"TreeId (4 bytes): Uniquely identifies the tree connect for the
command. This MUST be 0 for the SMB2 TREE_CONNECT Request."

Signed-off-by: Jan-Marek Glogowski <glogow@fbihome.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Tested-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:38:33 +02:00