Граф коммитов

467 Коммитов

Автор SHA1 Сообщение Дата
Steve French 41e033fecd smb3: add mount option to allow RW caching of share accessed by only 1 client
If a share is known to be only to be accessed by one client, we
can aggressively cache writes not just reads to it.

Add "cache=" option (cache=singleclient) for mounting read write shares
(that will not be read or written to from other clients while we have
it mounted) in order to improve performance.

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-16 11:43:38 -05:00
Steve French 83bbfa706d smb3: add mount option to allow forced caching of read only share
If a share is immutable (at least for the period that it will
be mounted) it would be helpful to not have to revalidate
dentries repeatedly that we know can not be changed remotely.

Add "cache=" option (cache=ro) for mounting read only shares
in order to improve performance in cases in which we know that
the share will not be changing while it is in use.

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-09-16 11:43:37 -05:00
Amir Goldstein bf3c90ee1e cifs: copy_file_range needs to strip setuid bits and update timestamps
cifs has both source and destination inodes locked throughout the copy.
Like ->write_iter(), we update mtime and strip setuid bits of destination
file before copy and like ->read_iter(), we update atime of source file
after copy.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-18 14:03:03 -05:00
Linus Torvalds ae9b728c8d smb3/cifs fixes (3 for stable) and improvements including much faster encryption (SMB3.1.1 GCM)
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Merge tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs updates from Steve French:
 "Fixes (three for stable) and improvements including much faster
  encryption (SMB3.1.1 GCM)"

* tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (27 commits)
  smb3: smbdirect no longer experimental
  cifs: fix crash in smb2_compound_op()/smb2_set_next_command()
  cifs: fix crash in cifs_dfs_do_automount
  cifs: fix parsing of symbolic link error response
  cifs: refactor and clean up arguments in the reparse point parsing
  SMB3: query inode number on open via create context
  smb3: Send netname context during negotiate protocol
  smb3: do not send compression info by default
  smb3: add new mount option to retrieve mode from special ACE
  smb3: Allow query of symlinks stored as reparse points
  cifs: Fix a race condition with cifs_echo_request
  cifs: always add credits back for unsolicited PDUs
  fs: cifs: cifsssmb: Change return type of convert_ace_to_cifs_ace
  add some missing definitions
  cifs: fix typo in debug message with struct field ia_valid
  smb3: minor cleanup of compound_send_recv
  CIFS: Fix module dependency
  cifs: simplify code by removing CONFIG_CIFS_ACL ifdef
  cifs: Fix check for matching with existing mount
  cifs: Properly handle auto disabling of serverino option
  ...
2019-07-18 11:11:51 -07:00
Linus Torvalds 40f06c7995 Changes to copy_file_range for 5.3 from Dave and Amir:
- Create a generic copy_file_range handler and make individual
   filesystems responsible for calling it (i.e. no more assuming that
   do_splice_direct will work or is appropriate)
 - Refactor copy_file_range and remap_range parameter checking where they
   are the same
 - Install missing copy_file_range parameter checking(!)
 - Remove suid/sgid and update mtime like any other file write
 - Change the behavior so that a copy range crossing the source file's
   eof will result in a short copy to the source file's eof instead of
   EINVAL
 - Permit filesystems to decide if they want to handle cross-superblock
   copy_file_range in their local handlers.
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Merge tag 'copy-file-range-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull copy_file_range updates from Darrick Wong:
 "This fixes numerous parameter checking problems and inconsistent
  behaviors in the new(ish) copy_file_range system call.

  Now the system call will actually check its range parameters
  correctly; refuse to copy into files for which the caller does not
  have sufficient privileges; update mtime and strip setuid like file
  writes are supposed to do; and allows copying up to the EOF of the
  source file instead of failing the call like we used to.

  Summary:

   - Create a generic copy_file_range handler and make individual
     filesystems responsible for calling it (i.e. no more assuming that
     do_splice_direct will work or is appropriate)

   - Refactor copy_file_range and remap_range parameter checking where
     they are the same

   - Install missing copy_file_range parameter checking(!)

   - Remove suid/sgid and update mtime like any other file write

   - Change the behavior so that a copy range crossing the source file's
     eof will result in a short copy to the source file's eof instead of
     EINVAL

   - Permit filesystems to decide if they want to handle
     cross-superblock copy_file_range in their local handlers"

* tag 'copy-file-range-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  fuse: copy_file_range needs to strip setuid bits and update timestamps
  vfs: allow copy_file_range to copy across devices
  xfs: use file_modified() helper
  vfs: introduce file_modified() helper
  vfs: add missing checks to copy_file_range
  vfs: remove redundant checks from generic_remap_checks()
  vfs: introduce generic_file_rw_checks()
  vfs: no fallback for ->copy_file_range
  vfs: introduce generic_copy_file_range()
2019-07-10 20:32:37 -07:00
Linus Torvalds 4d2fa8b44b Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "Here is the crypto update for 5.3:

  API:
   - Test shash interface directly in testmgr
   - cra_driver_name is now mandatory

  Algorithms:
   - Replace arc4 crypto_cipher with library helper
   - Implement 5 way interleave for ECB, CBC and CTR on arm64
   - Add xxhash
   - Add continuous self-test on noise source to drbg
   - Update jitter RNG

  Drivers:
   - Add support for SHA204A random number generator
   - Add support for 7211 in iproc-rng200
   - Fix fuzz test failures in inside-secure
   - Fix fuzz test failures in talitos
   - Fix fuzz test failures in qat"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits)
  crypto: stm32/hash - remove interruptible condition for dma
  crypto: stm32/hash - Fix hmac issue more than 256 bytes
  crypto: stm32/crc32 - rename driver file
  crypto: amcc - remove memset after dma_alloc_coherent
  crypto: ccp - Switch to SPDX license identifiers
  crypto: ccp - Validate the the error value used to index error messages
  crypto: doc - Fix formatting of new crypto engine content
  crypto: doc - Add parameter documentation
  crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR
  crypto: arm64/aes-ce - add 5 way interleave routines
  crypto: talitos - drop icv_ool
  crypto: talitos - fix hash on SEC1.
  crypto: talitos - move struct talitos_edesc into talitos.h
  lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE
  crypto/NX: Set receive window credits to max number of CRBs in RxFIFO
  crypto: asymmetric_keys - select CRYPTO_HASH where needed
  crypto: serpent - mark __serpent_setkey_sbox noinline
  crypto: testmgr - dynamically allocate crypto_shash
  crypto: testmgr - dynamically allocate testvec_config
  crypto: talitos - eliminate unneeded 'done' functions at build time
  ...
2019-07-08 20:57:08 -07:00
Steve French 412094a8fb smb3: add new mount option to retrieve mode from special ACE
There is a special ACE used by some servers to allow the mode
bits to be stored.  This can be especially helpful in scenarios
in which the client is trusted, and access checking on the
client vs the POSIX mode bits is sufficient.

Add mount option to allow enabling this behavior.
Follow on patch will add support for chmod and queryinfo
(stat) by retrieving the POSIX mode bits from the special
ACE, SID: S-1-5-88-3

See e.g.
https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/hh509017(v=ws.10)

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-07-07 22:37:43 -05:00
Steve French 73cf8085dc cifs: simplify code by removing CONFIG_CIFS_ACL ifdef
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>
2019-07-07 22:37:43 -05:00
Steve French dc179268cd smb3: if max_credits is specified then display it in /proc/mounts
If "max_credits" is overridden from its default by specifying
it on the smb3 mount then display it in /proc/mounts

Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07 22:37:43 -05:00
Aurelien Aptel 5fc3681fa5 cifs: add missing GCM module dependency
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-07-07 22:37:42 -05:00
Ard Biesheuvel 97a5fee2bd fs: cifs: switch to RC4 library interface
The CIFS code uses the sync skcipher API to invoke the ecb(arc4) skcipher,
of which only a single generic C code implementation exists. This means
that going through all the trouble of using scatterlists etc buys us
very little, and we're better off just invoking the arc4 library directly.

This also reverts commit 5f4b55699a ("CIFS: Fix BUG() in calc_seckey()"),
since it is no longer necessary to allocate sec_key on the heap.

Cc: linux-cifs@vger.kernel.org
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-06-20 14:19:55 +08:00
Ronnie Sahlberg 487317c994 cifs: add spinlock for the openFileList to cifsInodeInfo
We can not depend on the tcon->open_file_lock here since in multiuser mode
we may have the same file/inode open via multiple different tcons.

The current code is race prone and will crash if one user deletes a file
at the same time a different user opens/create the file.

To avoid this we need to have a spinlock attached to the inode and not the tcon.

RHBZ:  1580165

CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2019-06-13 14:21:09 -05:00
Amir Goldstein 5dae222a5f vfs: allow copy_file_range to copy across devices
We want to enable cross-filesystem copy_file_range functionality
where possible, so push the "same superblock only" checks down to
the individual filesystem callouts so they can make their own
decisions about cross-superblock copy offload and fallack to
generic_copy_file_range() for cross-superblock copy.

[Amir] We do not call ->remap_file_range() in case the files are not
on the same sb and do not call ->copy_file_range() in case the files
do not belong to the same filesystem driver.

This changes behavior of the copy_file_range(2) syscall, which will
now allow cross filesystem in-kernel copy.  CIFS already supports
cross-superblock copy, between two shares to the same server. This
functionality will now be available via the copy_file_range(2) syscall.

Cc: Steve French <stfrench@microsoft.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-09 10:06:20 -07:00
Dave Chinner 64bf5ff58d vfs: no fallback for ->copy_file_range
Now that we have generic_copy_file_range(), remove it as a fallback
case when offloads fail. This puts the responsibility for executing
fallbacks on the filesystems that implement ->copy_file_range and
allows us to add operational validity checks to
generic_copy_file_range().

Rework vfs_copy_file_range() to call a new do_copy_file_range()
helper to execute the copying callout, and move calls to
generic_file_copy_range() into filesystem methods where they
currently return failures.

[Amir] overlayfs is not responsible of executing the fallback.
It is the responsibility of the underlying filesystem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2019-06-09 10:06:19 -07:00
Ronnie Sahlberg dece44e381 cifs: add support for SEEK_DATA and SEEK_HOLE
Add llseek op for SEEK_DATA and SEEK_HOLE.
Improves xfstests/285,286,436,445,448 and 490

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-15 22:27:53 -05:00
Kovtunenko Oleksandr 9ab70ca653 Fixed https://bugzilla.kernel.org/show_bug.cgi?id=202935 allow write on the same file
Copychunk allows source and target to be on the same file.
For details on restrictions see MS-SMB2 3.3.5.15.6

Signed-off-by: Kovtunenko Oleksandr <alexander198961@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-15 22:27:53 -05:00
Ronnie Sahlberg 2f3ebaba13 cifs: add fiemap support
Useful for improved copy performance as well as for
applications which query allocated ranges of sparse
files.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:55 -05:00
Kenneth D'souza c8b6ac1a9d CIFS: Show locallease in /proc/mounts for cifs shares mounted with locallease feature.
Missing parameter that should be displayed in the mount list

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-05-07 23:24:54 -05:00
Al Viro c2e6802e7b cifs: switch to ->free_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-01 22:43:24 -04:00
Steve French ca567eb2b3 SMB3: Allow persistent handle timeout to be configurable on mount
Reconnecting after server or network failure can be improved
(to maintain availability and protect data integrity) by allowing
the client to choose the default persistent (or resilient)
handle timeout in some use cases.  Today we default to 0 which lets
the server pick the default timeout (usually 120 seconds) but this
can be problematic for some workloads.  Add the new mount parameter
to cifs.ko for SMB3 mounts "handletimeout" which enables the user
to override the default handle timeout for persistent (mount
option "persistenthandles") or resilient handles (mount option
"resilienthandles").  Maximum allowed is 16 minutes (960000 ms).
Units for the timeout are expressed in milliseconds. See
section 2.2.14.2.12 and 2.2.31.3 of the MS-SMB2 protocol
specification for more information.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
2019-04-01 14:33:36 -05:00
Xiaoli Feng b073a08016 cifs: fix that return -EINVAL when do dedupe operation
dedupe_file_range operations is combiled into remap_file_range.
But it's always skipped for dedupe operations in function
cifs_remap_file_range.

Example to test:
Before this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Invalid argument

After this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Operation not supported

Influence for xfstests:
generic/091
generic/112
generic/127
generic/263
These tests report this error "do_copy_range:: Invalid
argument" instead of "FIDEDUPERANGE: Invalid argument".
Because there are still two bugs cause these test failed.
https://bugzilla.kernel.org/show_bug.cgi?id=202935
https://bugzilla.kernel.org/show_bug.cgi?id=202785

Signed-off-by: Xiaoli Feng <fengxiaoli0714@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2019-03-22 22:36:54 -05:00
Steve French 96281b9e46 smb3: for kerberos mounts display the credential uid used
For kerberos mounts, the cruid is helpful to display in
/proc/mounts in order to tell which uid's krb5 cache we
got the ticket for and to tell in the multiuser krb5 case
which local users (uids) we have Kerberos authentic sessions
for.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2019-03-05 18:10:48 -06:00
Steve French e8506d25f7 smb3: make default i/o size for smb3 mounts larger
We negotiate rsize mounts (and it can be overridden by user) to
typically 4MB, so using larger default I/O sizes from userspace
(changing to 1MB default i/o size returned by stat) the
performance is much better (and not just for long latency
network connections) in most use cases for SMB3 than the default I/O
size (which ends up being 128K for cp and can be even smaller for cp).
This can be 4x slower or worse depending on network latency.

By changing inode->blocksize from 32K (which was perhaps ok
for very old SMB1/CIFS) to a larger value, 1MB (but still less than
max size negotiated with the server which is 4MB, in order to minimize
risk) it significantly increases performance for the
noncached case, and slightly increases it for the cached case.
This can be changed by the user on mount (specifying bsize=
values from 16K to 16MB) to tune better for performance
for applications that depend on blocksize.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
2019-03-04 20:05:35 -06:00
Paulo Alcantara 1c780228e9 cifs: Make use of DFS cache to get new DFS referrals
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>
2018-12-28 10:09:46 -06:00
Colin Ian King 8c6c9bed87 cifs: don't dereference smb_file_target before null check
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>
2018-11-02 14:09:42 -05:00
Long Li be4eb68846 CIFS: Add direct I/O functions to file_operations
With direct read/write functions implemented, add them to file_operations.

Dircet I/O is used under two conditions:
1. When mounting with "cache=none", CIFS uses direct I/O for all user file
data transfer.
2. When opening a file with O_DIRECT, CIFS uses direct I/O for all data
transfer on this file.

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-11-02 14:09:42 -05:00
Linus Torvalds c2aa1a444c vfs: rework data cloning infrastructure
Rework the vfs_clone_file_range and vfs_dedupe_file_range infrastructure to use
 a common .remap_file_range method and supply generic bounds and sanity checking
 functions that are shared with the data write path. The current VFS
 infrastructure has problems with rlimit, LFS file sizes, file time stamps,
 maximum filesystem file sizes, stripping setuid bits, etc and so they are
 addressed in these commits.
 
 We also introduce the ability for the ->remap_file_range methods to return short
 clones so that clones for vfs_copy_file_range() don't get rejected if the entire
 range can't be cloned. It also allows filesystems to sliently skip deduplication
 of partial EOF blocks if they are not capable of doing so without requiring
 errors to be thrown to userspace.
 
 All existing filesystems are converted to user the new .remap_file_range method,
 and both XFS and ocfs2 are modified to make use of the new generic checking
 infrastructure.
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Merge tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull vfs dedup fixes from Dave Chinner:
 "This reworks the vfs data cloning infrastructure.

  We discovered many issues with these interfaces late in the 4.19 cycle
  - the worst of them (data corruption, setuid stripping) were fixed for
  XFS in 4.19-rc8, but a larger rework of the infrastructure fixing all
  the problems was needed. That rework is the contents of this pull
  request.

  Rework the vfs_clone_file_range and vfs_dedupe_file_range
  infrastructure to use a common .remap_file_range method and supply
  generic bounds and sanity checking functions that are shared with the
  data write path. The current VFS infrastructure has problems with
  rlimit, LFS file sizes, file time stamps, maximum filesystem file
  sizes, stripping setuid bits, etc and so they are addressed in these
  commits.

  We also introduce the ability for the ->remap_file_range methods to
  return short clones so that clones for vfs_copy_file_range() don't get
  rejected if the entire range can't be cloned. It also allows
  filesystems to sliently skip deduplication of partial EOF blocks if
  they are not capable of doing so without requiring errors to be thrown
  to userspace.

  Existing filesystems are converted to user the new remap_file_range
  method, and both XFS and ocfs2 are modified to make use of the new
  generic checking infrastructure"

* tag 'xfs-4.20-merge-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (28 commits)
  xfs: remove [cm]time update from reflink calls
  xfs: remove xfs_reflink_remap_range
  xfs: remove redundant remap partial EOF block checks
  xfs: support returning partial reflink results
  xfs: clean up xfs_reflink_remap_blocks call site
  xfs: fix pagecache truncation prior to reflink
  ocfs2: remove ocfs2_reflink_remap_range
  ocfs2: support partial clone range and dedupe range
  ocfs2: fix pagecache truncation prior to reflink
  ocfs2: truncate page cache for clone destination file before remapping
  vfs: clean up generic_remap_file_range_prep return value
  vfs: hide file range comparison function
  vfs: enable remap callers that can handle short operations
  vfs: plumb remap flags through the vfs dedupe functions
  vfs: plumb remap flags through the vfs clone functions
  vfs: make remap_file_range functions take and return bytes completed
  vfs: remap helper should update destination inode metadata
  vfs: pass remap flags to generic_remap_checks
  vfs: pass remap flags to generic_remap_file_range_prep
  vfs: combine the clone and dedupe into a single remap_file_range
  ...
2018-11-02 09:33:08 -07:00
Darrick J. Wong 42ec3d4c02 vfs: make remap_file_range functions take and return bytes completed
Change the remap_file_range functions to take a number of bytes to
operate upon and return the number of bytes they operated on.  This is a
requirement for allowing fs implementations to return short clone/dedupe
results to the user, which will enable us to obey resource limits in a
graceful manner.

A subsequent patch will enable copy_file_range to signal to the
->clone_file_range implementation that it can handle a short length,
which will be returned in the function's return value.  For now the
short return is not implemented anywhere so the behavior won't change --
either copy_file_range manages to clone the entire range or it tries an
alternative.

Neither clone ioctl can take advantage of this, alas.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30 10:41:49 +11:00
Darrick J. Wong 2e5dfc99f2 vfs: combine the clone and dedupe into a single remap_file_range
Combine the clone_file_range and dedupe_file_range operations into a
single remap_file_range file operation dispatch since they're
fundamentally the same operation.  The differences between the two can
be made in the prep functions.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2018-10-30 10:41:21 +11:00
Steve French 8c1beb9801 cifs: minor clarification in comments
Clarify meaning (in comments) meaning of various
options for debug messages in cifs.ko. Also fixed
trivial formatting/style issue with previous patch.

Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:05 -05:00
Rodrigo Freire f80eaedd6c CIFS: Print message when attempting a mount
Currently, no messages are printed when mounting a CIFS filesystem and
no debug configuration is enabled.

However, a CIFS mount information is valuable when troubleshooting
and/or forensic analyzing a system and finding out if was a CIFS
endpoint mount attempted.

Other filesystems such as XFS, EXT* does issue a printk() when mounting
their filesystems.

A terse log message is printed only if cifsFYI is not enabled. Otherwise,
the default full debug message is printed.

In order to not clutter and classify correctly the event messages, these
are logged as KERN_INFO level.

Sample mount operations:

[root@corinthians ~]# mount -o user=administrator //172.25.250.18/c$ /mnt
(non-existent system)

[root@corinthians ~]# mount -o user=administrator //172.25.250.19/c$ /mnt
(Valid system)

Kernel message log for the mount operations:

[  450.464543] CIFS: Attempting to mount //172.25.250.18/c$
[  456.478186] CIFS VFS: Error connecting to socket. Aborting operation.
[  456.478381] CIFS VFS: cifs_mount failed w/return code = -113
[  467.688866] CIFS: Attempting to mount //172.25.250.19/c$

Signed-off-by: Rodrigo Freire <rfreire@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2018-10-23 21:16:05 -05:00
Aurelien Aptel 8393072bab CIFS: make 'nodfs' mount opt a superblock flag
tcon->Flags is only used by SMB1 code and changing it is not permanent
(you lose the setting on tcon reconnect).

* Move the setting to superblock flags (per mount-points).
* Make automount callback exit early when flag present
* Make dfs resolving happening in mount syscall exit early if flag present

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-10-23 21:16:05 -05:00
Steve French 00778e2294 smb3: add way to control slow response threshold for logging and stats
/proc/fs/cifs/Stats when CONFIG_CIFS_STATS2 is enabled logs 'slow'
responses, but depending on the server you are debugging a
one second timeout may be too fast, so allow setting it to
a larger number of seconds via new module parameter

/sys/module/cifs/parameters/slow_rsp_threshold

or via modprobe:

slow_rsp_threshold:Amount of time (in seconds) to wait before
logging that a response is delayed.
Default: 1 (if set to 0 disables msg). (uint)

Recommended values are 0 (disabled) to 32767 (9 hours) with
the default remaining as 1 second.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-10-23 21:16:04 -05:00
Steve French 1c3a13a38a cifs: minor updates to module description for cifs.ko
note smb3 (and common more modern servers) in the module description

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-10-23 21:16:04 -05:00
Ronnie Sahlberg e55954a5f7 cifs: don't show domain= in mount output when domain is empty
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-08-10 11:53:51 -05:00
Steve French 8a69e96e61 smb3: snapshot mounts are read-only and make sure info is displayable about the mount
snapshot mounts were not marked as read-only and did not display the snapshot
time (in /proc/mounts) specified on mount

With this patch - note that can not write to the snapshot mount (see "ro" in
/proc/mounts line) and also the missing snapshot timewarp token time is
dumped.  Sample line from /proc/mounts with the patch:

//127.0.0.1/scratch /mnt2 smb3 ro,relatime,vers=default,cache=strict,username=testuser,domain=,uid=0,noforceuid,gid=0,noforcegid,addr=127.0.0.1,file_mode=0755,dir_mode=0755,soft,nounix,serverino,mapposix,noperm,rsize=1048576,wsize=1048576,echo_interval=60,snapshot=1234567,actimeo=1 0 0

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
2018-08-07 14:15:56 -05:00
Steve French 0fdfef9aa7 smb3: simplify code by removing CONFIG_CIFS_SMB311
We really, really want to be encouraging use of secure dialects,
and SMB3.1.1 offers useful security features, and will soon
be the recommended dialect for many use cases. Simplify the code
by removing the CONFIG_CIFS_SMB311 ifdef so users don't disable
it in the build, and create compatibility and/or security issues
with modern servers - many of which have been supporting this
dialect for multiple years.

Also clarify some of the Kconfig text for cifs.ko about
SMB3.1.1 and current supported features in the module.

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-08-07 14:15:56 -05:00
Steve French 21ba3845b5 smb3: fill in statfs fsid and correct namelen
Fil in the correct namelen (typically 255 not 4096) in the
statfs response and also fill in a reasonably unique fsid
(in this case taken from the volume id, and the creation time
of the volume).

In the case of the POSIX statfs all fields are now filled in,
and in the case of non-POSIX mounts, all fields are filled
in which can be.

Signed-off-by: Steve French <stfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
2018-08-07 14:15:41 -05:00
Steve French c7c137b931 smb3: do not allow insecure cifs mounts when using smb3
if mounting as smb3 do not allow cifs (vers=1.0) or insecure vers=2.0
mounts.

For example:
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1
root@smf-Thinkpad-P51:~/cifs-2.6# umount /mnt
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1,vers=1.0
mount: /mnt: wrong fs type, bad option, bad superblock on //127.0.0.1/scratch ...
root@smf-Thinkpad-P51:~/cifs-2.6# dmesg | grep smb3
[ 4302.200122] CIFS VFS: vers=1.0 (cifs) not permitted when mounting with smb3
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1,vers=3.11

Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Sachin Prabhu <sprabhu@redhat.com>
2018-06-07 08:36:39 -05:00
Steve French b326614ea2 smb3: allow "posix" mount option to enable new SMB311 protocol extensions
If "posix" (or synonym "unix" for backward compatibility) specified on mount,
and server advertises support for SMB3.11 POSIX negotiate context, then
enable the new posix extensions on the tcon.  This can be viewed by
looking for "posix" in the mount options displayed by /proc/mounts
for that mount (ie if posix extensions allowed by server and the
experimental POSIX extensions also requested on the mount by specifying
"posix" at mount time).

Also add check to warn user if conflicting unix/nounix or posix/noposix specified
on mount.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French f92a720ee9 cifs: allow disabling less secure legacy dialects
To improve security it may be helpful to have additional ways to restrict the
ability to override the default dialects (SMB2.1, SMB3 and SMB3.02) on mount
with old dialects (CIFS/SMB1 and SMB2) since vers=1.0 (CIFS/SMB1) and vers=2.0
are weaker and less secure.

Add a module parameter "disable_legacy_dialects"
(/sys/module/cifs/parameters/disable_legacy_dialects) which can be set to
1 (or equivalently Y) to forbid use of vers=1.0 or vers=2.0 on mount.

Also cleans up a few build warnings about globals for various module parms.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French 11911b956f cifs: make minor clarifications to module params for cifs.ko
Note which ones of the module params are cifs dialect only
(N/A for default dialect now that has moved to SMB2.1 or later)

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-30 16:06:18 -05:00
Steve French 49218b4f57 smb3: add module alias for smb3 to cifs.ko
We really don't want to be encouraging people to use the old
(less secure) cifs dialect (SMB1) and it can be confusing for them
with SMB3 (or later) being recommended but the module name is cifs.

Add a module alias for "smb3" to cifs.ko to make this less confusing.

Signed-off-by: Steve French <smfrench@gmail.com>
2018-05-30 16:06:18 -05:00
Steve French 3d4ef9a153 smb3: fix redundant opens on root
In SMB2/SMB3 unlike in cifs we unnecessarily open the root of the share
over and over again in various places during mount and path revalidation
and also in statfs.  This patch cuts redundant traffic (opens and closes)
by simply keeping the directory handle for the root around (and reopening
it as needed on reconnect), so query calls don't require three round
trips to copmlete - just one, and eases load on network, client and
server (on mount alone, cuts network traffic by more than a third).

Also add a new cifs mount parm "nohandlecache" to allow users whose
servers might have resource constraints (eg in case they have a server
with so many users connecting to it that this extra handle per mount
could possibly be a resource concern).

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-05-27 17:56:35 -05:00
Steve French 6e70c267e6 smb3: directory sync should not return an error
As with NFS, which ignores sync on directory handles,
fsync on a directory handle is a noop for CIFS/SMB3.
Do not return an error on it.  It breaks some database
apps otherwise.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
2018-05-10 19:21:14 -05:00
Aurelien Aptel 5fcd7f3f96 CIFS: add sha512 secmech
* prepare for SMB3.11 pre-auth integrity
* enable sha512 when SMB311 is enabled in Kconfig
* add sha512 as a soft dependency

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
2018-04-01 20:24:39 -05:00
Linus Torvalds 617aebe6a9 Currently, hardened usercopy performs dynamic bounds checking on slab
cache objects. This is good, but still leaves a lot of kernel memory
 available to be copied to/from userspace in the face of bugs. To further
 restrict what memory is available for copying, this creates a way to
 whitelist specific areas of a given slab cache object for copying to/from
 userspace, allowing much finer granularity of access control. Slab caches
 that are never exposed to userspace can declare no whitelist for their
 objects, thereby keeping them unavailable to userspace via dynamic copy
 operations. (Note, an implicit form of whitelisting is the use of constant
 sizes in usercopy operations and get_user()/put_user(); these bypass all
 hardened usercopy checks since these sizes cannot change at runtime.)
 
 This new check is WARN-by-default, so any mistakes can be found over the
 next several releases without breaking anyone's system.
 
 The series has roughly the following sections:
 - remove %p and improve reporting with offset
 - prepare infrastructure and whitelist kmalloc
 - update VFS subsystem with whitelists
 - update SCSI subsystem with whitelists
 - update network subsystem with whitelists
 - update process memory with whitelists
 - update per-architecture thread_struct with whitelists
 - update KVM with whitelists and fix ioctl bug
 - mark all other allocations as not whitelisted
 - update lkdtm for more sensible test overage
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 Comment: Kees Cook <kees@outflux.net>
 
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Merge tag 'usercopy-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardened usercopy whitelisting from Kees Cook:
 "Currently, hardened usercopy performs dynamic bounds checking on slab
  cache objects. This is good, but still leaves a lot of kernel memory
  available to be copied to/from userspace in the face of bugs.

  To further restrict what memory is available for copying, this creates
  a way to whitelist specific areas of a given slab cache object for
  copying to/from userspace, allowing much finer granularity of access
  control.

  Slab caches that are never exposed to userspace can declare no
  whitelist for their objects, thereby keeping them unavailable to
  userspace via dynamic copy operations. (Note, an implicit form of
  whitelisting is the use of constant sizes in usercopy operations and
  get_user()/put_user(); these bypass all hardened usercopy checks since
  these sizes cannot change at runtime.)

  This new check is WARN-by-default, so any mistakes can be found over
  the next several releases without breaking anyone's system.

  The series has roughly the following sections:
   - remove %p and improve reporting with offset
   - prepare infrastructure and whitelist kmalloc
   - update VFS subsystem with whitelists
   - update SCSI subsystem with whitelists
   - update network subsystem with whitelists
   - update process memory with whitelists
   - update per-architecture thread_struct with whitelists
   - update KVM with whitelists and fix ioctl bug
   - mark all other allocations as not whitelisted
   - update lkdtm for more sensible test overage"

* tag 'usercopy-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (38 commits)
  lkdtm: Update usercopy tests for whitelisting
  usercopy: Restrict non-usercopy caches to size 0
  kvm: x86: fix KVM_XEN_HVM_CONFIG ioctl
  kvm: whitelist struct kvm_vcpu_arch
  arm: Implement thread_struct whitelist for hardened usercopy
  arm64: Implement thread_struct whitelist for hardened usercopy
  x86: Implement thread_struct whitelist for hardened usercopy
  fork: Provide usercopy whitelisting for task_struct
  fork: Define usercopy region in thread_stack slab caches
  fork: Define usercopy region in mm_struct slab caches
  net: Restrict unwhitelisted proto caches to size 0
  sctp: Copy struct sctp_sock.autoclose to userspace using put_user()
  sctp: Define usercopy region in SCTP proto slab cache
  caif: Define usercopy region in caif proto slab cache
  ip: Define usercopy region in IP proto slab cache
  net: Define usercopy region in struct proto slab cache
  scsi: Define usercopy region in scsi_sense_cache slab cache
  cifs: Define usercopy region in cifs_request slab cache
  vxfs: Define usercopy region in vxfs_inode slab cache
  ufs: Define usercopy region in ufs_inode_cache slab cache
  ...
2018-02-03 16:25:42 -08:00
Andrés Souto cd1aca29fa cifs: add .splice_write
add splice_write support in cifs vfs using iter_file_splice_write

Signed-off-by: Andrés Souto <kai670@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2018-01-26 17:03:01 -06:00
Long Li 8339dd32fb CIFS: SMBD: Add rdma mount option
Add "rdma" to CIFS mount options to connect to SMB Direct.
Add checks to validate this is used on SMB 3.X dialects.

To connect to SMBDirect, use "mount.cifs -o rdma,vers=3.x".
At the time of this patch, 3.x can be 3.0, 3.02 or 3.1.1.

Signed-off-by: Long Li <longli@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber.redhat.com>
2018-01-24 19:49:05 -06:00
David Windsor de04644904 cifs: Define usercopy region in cifs_request slab cache
CIFS request buffers, stored in the cifs_request slab cache, need to be
copied to/from userspace.

cache object allocation:
    fs/cifs/cifsfs.c:
        cifs_init_request_bufs():
            ...
            cifs_req_poolp = mempool_create_slab_pool(cifs_min_rcv,
                                                      cifs_req_cachep);

    fs/cifs/misc.c:
        cifs_buf_get():
            ...
            ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
            ...
            return ret_buf;

In support of usercopy hardening, this patch defines a region in the
cifs_request slab cache in which userspace copy operations are allowed.

This region is known as the slab cache's usercopy region. Slab caches
can now check that each dynamically sized copy operation involving
cache-managed memory falls entirely within the slab's usercopy region.

This patch is verbatim from Brad Spengler/PaX Team's PAX_USERCOPY
whitelisting code in the last public patch of grsecurity/PaX based on my
understanding of the code. Changes or omissions from the original code are
mine and don't reflect the original grsecurity/PaX code.

Signed-off-by: David Windsor <dave@nullcore.net>
[kees: adjust commit log, provide usage trace]
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-01-15 12:07:57 -08:00