Commit Graph

2984 Commits

Author SHA1 Message Date
Steve French
38bd575b9a SMB3: Fix SMB3.1.1 guest mounts to Samba
commit 8c11a607d1 upstream.

Workaround problem with Samba responses to SMB3.1.1
null user (guest) mounts.  The server doesn't set the
expected flag in the session setup response so we have
to do a similar check to what is done in smb3_validate_negotiate
where we also check if the user is a null user (but not sec=krb5
since username might not be passed in on mount for Kerberos case).

Note that the commit below tightened the conditions and forced signing
for the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
cases where there is no user (even if server forgets to set the flag
in the response) since we don't have anything useful to sign with.
This is especially important now that the more secure SMB3.1.1 protocol
is in the default dialect list.

An earlier patch ("cifs: allow guest mounts to work for smb3.11") fixed
the guest mounts to Windows.

    Fixes: 6188f28bf6 ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27 14:14:41 +09:00
Ronnie Sahlberg
14c52acaac cifs: allow guest mounts to work for smb3.11
commit e71ab2aa06 upstream.

Fix Guest/Anonymous sessions so that they work with SMB 3.11.

The commit noted below tightened the conditions and forced signing for
the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
Guest/Anonumous sessions.

Fixes: 6188f28bf6 ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27 14:14:40 +09:00
Pavel Shilovsky
43eaa6cc17 CIFS: Fix read after write for files with read caching
commit 6dfbd84684 upstream.

When we have a READ lease for a file and have just issued a write
operation to the server we need to purge the cache and set oplock/lease
level to NONE to avoid reading stale data. Currently we do that
only if a write operation succedeed thus not covering cases when
a request was sent to the server but a negative error code was
returned later for some other reasons (e.g. -EIOCBQUEUED or -EINTR).
Fix this by turning off caching regardless of the error code being
returned.

The patches fixes generic tests 075 and 112 from the xfs-tests.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:09:56 +01:00
Pavel Shilovsky
dc8e8ad962 CIFS: Do not skip SMB2 message IDs on send failures
commit c781af7e0c upstream.

When we hit failures during constructing MIDs or sending PDUs
through the network, we end up not using message IDs assigned
to the packet. The next SMB packet will skip those message IDs
and continue with the next one. This behavior may lead to a server
not granting us credits until we use the skipped IDs. Fix this by
reverting the current ID to the original value if any errors occur
before we push the packet through the network stack.

This patch fixes the generic/310 test from the xfs-tests.

Cc: <stable@vger.kernel.org> # 4.19.x
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:09:56 +01:00
Pavel Shilovsky
3ed9f22e28 CIFS: Do not reset lease state to NONE on lease break
commit 7b9b9edb49 upstream.

Currently on lease break the client sets a caching level twice:
when oplock is detected and when oplock is processed. While the
1st attempt sets the level to the value provided by the server,
the 2nd one resets the level to None unconditionally.
This happens because the oplock/lease processing code was changed
to avoid races between page cache flushes and oplock breaks.
The commit c11f1df500 ("cifs: Wait for writebacks to complete
before attempting write.") fixed the races for oplocks but didn't
apply the same changes for leases resulting in overwriting the
server granted value to None. Fix this by properly processing
lease breaks.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:09:56 +01:00
Ronnie Sahlberg
b4d965a37d cifs: allow calling SMB2_xxx_free(NULL)
commit 32a1fb36f6 upstream.

Change these free functions to allow passing NULL as the argument and
treat it as a no-op just like free(NULL) would.
Or, if rqst->rq_iov is NULL.

The second scenario could happen for smb2_queryfs() if the call
to SMB2_query_info_init() fails and we go to qfs_exit to clean up
and free all resources.
In that case we have not yet assigned rqst[2].rq_iov and thus
the rq_iov dereference in SMB2_close_free() will cause a NULL pointer
dereference.

[ bp: upstream patch also fixes SMB2_set_info_free which was introduced in 4.20 ]

Fixes:  1eb9fb5204 ("cifs: create SMB2_open_init()/SMB2_open_free() helpers")

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-13 14:02:40 -07:00
Ronnie Sahlberg
6efd69d633 cifs: fix computation for MAX_SMB2_HDR_SIZE
[ Upstream commit 58d15ed120 ]

The size of the fixed part of the create response is 88 bytes not 56.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:31 -07:00
Pavel Shilovsky
b1765ebd9d CIFS: Do not assume one credit for async responses
[ Upstream commit 0fd1d37b05 ]

If we don't receive a response we can't assume that the server
granted one credit. Assume zero credits in such cases.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20 10:25:44 +01:00
Ross Lagerwall
63715c1f0a cifs: Limit memory used by lock request calls to a page
[ Upstream commit 92a8109e4d ]

The code tries to allocate a contiguous buffer with a size supplied by
the server (maxBuf). This could fail if memory is fragmented since it
results in high order allocations for commonly used server
implementations. It is also wasteful since there are probably
few locks in the usual case. Limit the buffer to be no larger than a
page to avoid memory allocation failures due to fragmentation.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-20 10:25:43 +01:00
Ronnie Sahlberg
5d3b4cd873 cifs: check ntwrk_buf_start for NULL before dereferencing it
[ Upstream commit 59a63e479c ]

RHBZ: 1021460

There is an issue where when multiple threads open/close the same directory
ntwrk_buf_start might end up being NULL, causing the call to smbCalcSize
later to oops with a NULL deref.

The real bug is why this happens and why this can become NULL for an
open cfile, which should not be allowed.
This patch tries to avoid a oops until the time when we fix the underlying
issue.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-12 19:47:17 +01:00
Paulo Alcantara
c0be624777 cifs: Always resolve hostname before reconnecting
commit 28eb24ff75 upstream.

In case a hostname resolves to a different IP address (e.g. long
running mounts), make sure to resolve it every time prior to calling
generic_ip_connect() in reconnect.

Suggested-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:16 +01:00
Pavel Shilovsky
e9d56f920b CIFS: Do not consider -ENODATA as stat failure for reads
commit 082aaa8700 upstream.

When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Pavel Shilovsky
6e7045ec33 CIFS: Fix trace command logging for SMB2 reads and writes
commit 7d42e72fe8 upstream.

Currently we log success once we send an async IO request to
the server. Instead we need to analyse a response and then log
success or failure for a particular command. Also fix argument
list for read logging.

Cc: <stable@vger.kernel.org> # 4.18
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Pavel Shilovsky
c6961288a5 CIFS: Do not count -ENODATA as failure for query directory
commit 8e6e72aece upstream.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:11 +01:00
Ronnie Sahlberg
06d9f98720 smb3: add credits we receive from oplock/break PDUs
commit 2e5700bdde upstream.

Otherwise we gradually leak credits leading to potential
hung session.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
779c65bb77 CIFS: Do not reconnect TCP session in add_credits()
commit ef68e83184 upstream.

When executing add_credits() we currently call cifs_reconnect()
if the number of credits is zero and there are no requests in
flight. In this case we may call cifs_reconnect() recursively
twice and cause memory corruption given the following sequence
of functions:

mid1.callback() -> add_credits() -> cifs_reconnect() ->
-> mid2.callback() -> add_credits() -> cifs_reconnect().

Fix this by avoiding to call cifs_reconnect() in add_credits()
and checking for zero credits in the demultiplex thread.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
2ae6fedbd5 CIFS: Fix credit calculation for encrypted reads with errors
commit ec678eae74 upstream.

We do need to account for credits received in error responses
to read requests on encrypted sessions.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
0380ed9b1c CIFS: Fix credits calculations for reads with errors
commit 8004c78c68 upstream.

Currently we mark MID as malformed if we get an error from server
in a read response. This leads to not properly processing credits
in the readv callback. Fix this by marking such a response as
normal received response and process it appropriately.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Pavel Shilovsky
07b9e5e35e CIFS: Fix possible hang during async MTU reads and writes
commit acc58d0bab upstream.

When doing MTU i/o we need to leave some credits for
possible reopen requests and other operations happening
in parallel. Currently we leave 1 credit which is not
enough even for reopen only: we need at least 2 credits
if durable handle reconnect fails. Also there may be
other operations at the same time including compounding
ones which require 3 credits at a time each. Fix this
by leaving 8 credits which is big enough to cover most
scenarios.

Was able to reproduce this when server was configured
to give out fewer credits than usual.

The proper fix would be to reconnect a file handle first
and then obtain credits for an MTU request but this leads
to bigger code changes and should happen in other patches.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:37 +01:00
Ross Lagerwall
2a71a47e03 cifs: Fix potential OOB access of lock element array
commit b9a74cde94 upstream.

If maxBuf is small but non-zero, it could result in a zero sized lock
element array which we would then try and access OOB.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:31 +01:00
Pavel Shilovsky
7dcc5b36ea CIFS: Fix credit computation for compounded requests
commit 8544f4aa9d upstream.

In SMB3 protocol every part of the compound chain consumes credits
individually, so we need to call wait_for_free_credits() for each
of the PDUs in the chain. If an operation is interrupted, we must
ensure we return all credits taken from the server structure back.

Without this patch server can sometimes disconnect the session
due to credit mismatches, especially when first operation(s)
are large writes.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:31 +01:00
Pavel Shilovsky
d2f76f6f9f CIFS: Do not hide EINTR after sending network packets
commit ee13919c2e upstream.

Currently we hide EINTR code returned from sock_sendmsg()
and return 0 instead. This makes a caller think that we
successfully completed the network operation which is not
true. Fix this by properly returning EINTR to callers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:30 +01:00
Pavel Shilovsky
c3606c6467 CIFS: Do not set credits to 1 if the server didn't grant anything
commit 33fa5c8b8a upstream.

Currently we reset the number of total credits granted by the server
to 1 if the server didn't grant us anything int the response. This
violates the SMB3 protocol - we need to trust the server and use
the credit values from the response. Fix this by removing the
corresponding code.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:30 +01:00
Pavel Shilovsky
d1130682d1 CIFS: Fix adjustment of credits for MTU requests
commit b983f7e923 upstream.

Currently for MTU requests we allocate maximum possible credits
in advance and then adjust them according to the request size.
While we were adjusting the number of credits belonging to the
server, we were skipping adjustment of credits belonging to the
request. This patch fixes it by setting request credits to
CreditCharge field value of SMB2 packet header.

Also ask 1 credit more for async read and write operations to
increase parallelism and match the behavior of other operations.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-16 22:04:30 +01:00
Paul Aurich
ba77e8c7f7 smb3: fix large reads on encrypted connections
commit 6d2f84eee0 upstream.

When passing a large read to receive_encrypted_read(), ensure that the
demultiplex_thread knows that a MID was processed.  Without this, those
operations never complete.

This is a similar issue/fix to lease break handling:
commit 7af929d6d0
("smb3: fix lease break problem introduced by compounding")

CC: Stable <stable@vger.kernel.org> # 4.19+
Fixes: b24df3e30c ("cifs: update receive_encrypted_standard to handle compounded responses")
Signed-off-by: Paul Aurich <paul@darkrain42.org>
Tested-by: Yves-Alexis Perez <corsac@corsac.net>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:48 +01:00
Georgy A Bystrenin
1827d1c439 CIFS: Fix error mapping for SMB2_LOCK command which caused OFD lock problem
commit 9a596f5b39 upstream.

While resolving a bug with locks on samba shares found a strange behavior.
When a file locked by one node and we trying to lock it from another node
it fail with errno 5 (EIO) but in that case errno must be set to
(EACCES | EAGAIN).
This isn't happening when we try to lock file second time on same node.
In this case it returns EACCES as expected.
Also this issue not reproduces when we use SMB1 protocol (vers=1.0 in
mount options).

Further investigation showed that the mapping from status_to_posix_error
is different for SMB1 and SMB2+ implementations.
For SMB1 mapping is [NT_STATUS_LOCK_NOT_GRANTED to ERRlock]
(See fs/cifs/netmisc.c line 66)
but for SMB2+ mapping is [STATUS_LOCK_NOT_GRANTED to -EIO]
(see fs/cifs/smb2maperror.c line 383)

Quick changes in SMB2+ mapping from EIO to EACCES has fixed issue.

BUG: https://bugzilla.kernel.org/show_bug.cgi?id=201971

Signed-off-by: Georgy A Bystrenin <gkot@altlinux.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:48 +01:00
Steve French
b5a8028c25 cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)
[ Upstream commit 6e785302da ]

Missing a dependency.  Shouldn't show cifs posix extensions
in Kconfig if CONFIG_CIFS_ALLOW_INSECURE_DIALECTS (ie SMB1
protocol) is disabled.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-12-21 14:15:23 +01:00
Paulo Alcantara
99c694081b cifs: Fix separator when building path from dentry
commit c988de29ca upstream.

Make sure to use the CIFS_DIR_SEP(cifs_sb) as path separator for
prefixpath too. Fixes a bug with smb1 UNIX extensions.

Fixes: a6b5058faf ("fs/cifs: make share unaccessible at root level mountable")
Signed-off-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-13 09:16:20 +01:00
Ronnie Sahlberg
e4ed4e68c6 cifs: fix return value for cifs_listxattr
[ Upstream commit 0c5d6cb664 ]

If the application buffer was too small to fit all the names
we would still count the number of bytes and return this for
listxattr. This would then trigger a BUG in usercopy.c

Fix the computation of the size so that we return -ERANGE
correctly when the buffer is too small.

This fixes the kernel BUG for xfstest generic/377

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-27 16:12:58 +01:00
Colin Ian King
ad1834fd8a cifs: don't dereference smb_file_target before null check
[ Upstream commit 8c6c9bed87 ]

There is a null check on dst_file->private data which suggests
it can be potentially null. However, before this check, pointer
smb_file_target is derived from dst_file->private and dereferenced
in the call to tlink_tcon, hence there is a potential null pointer
deference.

Fix this by assigning smb_file_target and target_tcon after the
null pointer sanity checks.

Detected by CoverityScan, CID#1475302 ("Dereference before null check")

Fixes: 04b38d6012 ("vfs: pull btrfs clone API to vfs layer")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-27 16:12:58 +01:00
Steve French
93e2e86745 smb3: on kerberos mount if server doesn't specify auth type use krb5
commit 926674de67 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>
2018-11-13 11:08:48 -08:00
Steve French
108b981d48 smb3: do not attempt cifs operation in smb3 query info error path
commit 1e77a8c204 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>
2018-11-13 11:08:48 -08:00
Steve French
eb7814c36f smb3: allow stats which track session and share reconnects to be reset
commit 2c887635cd 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>
2018-11-13 11:08:48 -08:00
Ronnie Sahlberg
c24f57c612 cifs: fix a credits leak for compund commands
[ Upstream commit cb5c2e6394 ]

When processing the mids for compounds we would only add credits based on
the last successful mid in the compound which would leak credits and
eventually triggering a re-connect.

Fix this by splitting the mid processing part into two loops instead of one
where the first loop just waits for all mids and then counts how many
credits we were granted for the whole compound.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-13 11:08:31 -08:00
Steve French
7af929d6d0 smb3: fix lease break problem introduced by compounding
Fixes problem (discovered by Aurelien) introduced by recent commit:
commit b24df3e30c
("cifs: update receive_encrypted_standard to handle compounded responses")

which broke the ability to respond to some lease breaks
(lease breaks being ignored is a problem since can block
server response for duration of the lease break timeout).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-02 18:54:09 -05:00
Ronnie Sahlberg
4e34feb5e9 cifs: only wake the thread for the very last PDU in a compound
For compounded PDUs we whould only wake the waiting thread for the
very last PDU of the compound.
We do this so that we are guaranteed that the demultiplex_thread will
not process or access any of those MIDs any more once the send/recv
thread starts processing.

Else there is a race where at the end of the send/recv processing we
will try to delete all the mids of the compound. If the multiplex
thread still has other mids to process at this point for this compound
this can lead to an oops.

Needed to fix recent commit:
commit 730928c8f4
("cifs: update smb2_queryfs() to use compounding")

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-02 18:53:57 -05:00
Ronnie Sahlberg
ddf83afb9f cifs: add a warning if we try to to dequeue a deleted mid
cifs_delete_mid() is called once we are finished handling a mid and we
expect no more work done on this mid.

Needed to fix recent commit:
commit 730928c8f4
("cifs: update smb2_queryfs() to use compounding")

Add a warning if someone tries to dequeue a mid that has already been
flagged to be deleted.
Also change list_del() to list_del_init() so that if we have similar bugs
resurface in the future we will not oops.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-02 18:12:31 -05:00
Aurelien Aptel
0595751f26 smb2: fix missing files in root share directory listing
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>
2018-10-02 18:06:21 -05:00
Dan Carpenter
097f5863b1 cifs: read overflow in is_valid_oplock_break()
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>
2018-09-12 17:13:34 -05:00
Dan Carpenter
2d204ee9d6 cifs: integer overflow in in SMB2_ioctl()
The "le32_to_cpu(rsp->OutputOffset) + *plen" addition can overflow and
wrap around to a smaller value which looks like it would lead to an
information leak.

Fixes: 4a72dafa19 ("SMB2 FSCTL and IOCTL worker function")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2018-09-12 09:32:07 -05:00
Dan Carpenter
56446f218a CIFS: fix wrapping bugs in num_entries()
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>
2018-09-12 09:32:07 -05:00
Dan Carpenter
8ad8aa3535 cifs: prevent integer overflow in nxt_dir_entry()
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>
2018-09-12 09:27:57 -05:00
Stefan Metzmacher
5890184d2b fs/cifs: require sha512
This got lost in commit 0fdfef9aa7,
which removed CONFIG_CIFS_SMB311.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Fixes: 0fdfef9aa7 ("smb3: simplify code by removing CONFIG_CIFS_SMB311")
CC: Stable <stable@vger.kernel.org>
CC: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-09-09 00:04:27 -05:00
Stephen Rothwell
bcfb84a996 fs/cifs: suppress a string overflow warning
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>
2018-09-09 00:02:39 -05:00
Thomas Werschlein
395a2076b4 cifs: connect to servername instead of IP for IPC$ share
This patch is required allows access to a Microsoft fileserver failover
cluster behind a 1:1 NAT firewall.

The change also provides stronger context for authentication and share
connection (see MS-SMB2 3.3.5.7 and MS-SRVS 3.1.6.8) as noted by
Tom Talpey, and addresses comments about the buffer size for the UNC
made by Aurélien Aptel.

Signed-off-by: Thomas Werschlein <thomas.werschlein@geo.uzh.ch>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Tom Talpey <ttalpey@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
2018-09-02 23:21:42 -05:00
Steve French
f801568332 smb3: check for and properly advertise directory lease support
Although servers will typically ignore unsupported features,
we should advertise the support for directory leases (as
Windows e.g. does) in the negotiate protocol capabilities we
pass to the server, and should check for the server capability
(CAP_DIRECTORY_LEASING) before sending a lease request for an
open of a directory.  This will prevent us from accidentally
sending directory leases to SMB2.1 or SMB2 server for example.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-09-02 23:21:42 -05:00
Steve French
25f2573512 smb3: minor debugging clarifications in rfc1001 len processing
I ran into some cases where server was returning the wrong length
on frames but I couldn't easily match them to the command in the
network trace (or server logs) since I need the command and/or
multiplex id to find the offending SMB2/SMB3 command.  Add these
two fields to the log message. In the case of padding too much
it may not be a problem in all cases but might have correlated
to a network disconnect case in some problems we have been
looking at. In the case of frame too short is even more important.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-09-02 23:21:42 -05:00
Steve French
5e19697b56 SMB3: Backup intent flag missing for directory opens with backupuid mounts
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag needs to be set
on opens of directories (and files) but was missing in some
places causing access denied trying to enumerate and backup
servers.

Fixes kernel bugzilla #200953
https://bugzilla.kernel.org/show_bug.cgi?id=200953

Reported-and-tested-by: <whh@rubrik.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-09-02 23:21:42 -05:00
Jon Kuhn
c15e3f19a6 fs/cifs: don't translate SFM_SLASH (U+F026) to backslash
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>
2018-09-02 23:21:42 -05:00
Steve French
7753e38286 cifs: update internal module version number for cifs.ko to 2.12
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-08-23 15:11:10 -05:00