Commit graph

94 commits

Author SHA1 Message Date
Paulo Alcantara
796733054e smb: client: fix noisy message when mounting shares
When the client unconditionally attempts to get an DFS referral to
check if share is DFS, some servers may return different errors that
aren't handled in smb2_get_dfs_refer(), so the following will be
logged in dmesg:

	CIFS: VFS: \\srv\IPC$ smb2_get_dfs_refer: ioctl error...

which can confuse some users while mounting an SMB share.

Fix this by logging such error with FYI.

Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-26 18:46:40 -06:00
Paulo Alcantara
e148107598 smb: client: allow reconnect when sending ioctl
cifs_tree_connect() no longer uses ioctl, so allow sessions to be
reconnected when sending ioctls.

Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-26 18:46:27 -06:00
Paulo Alcantara
bc925c1216 smb: client: improve compound padding in encryption
After commit f7f291e14d ("cifs: fix oops during encryption"), the
encryption layer can handle vmalloc'd buffers as well as kmalloc'd
buffers, so there is no need to inefficiently squash request iovs
into a single one to handle padding in compound requests.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-21 10:45:49 -06:00
Steve French
9ed9d83a51 smb3: request handle caching when caching directories
This client was only requesting READ caching, not READ and HANDLE caching
in the LeaseState on the open requests we send for directories.  To
delay closing a handle (e.g. for caching directory contents) we should
be requesting HANDLE as well as READ (as we already do for deferred
close of files).   See MS-SMB2 3.3.1.4 e.g.

Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-21 10:45:15 -06:00
Su Hui
19ebc1e6ca smb: client: fix possible double free in smb2_set_ea()
Clang static checker(scan-build) warning:
fs/smb/client/smb2ops.c:1304:2: Attempt to free released memory.
 1304 |         kfree(ea);
      |         ^~~~~~~~~

There is a double free in such case:
'ea is initialized to NULL' -> 'first successful memory allocation for
ea' -> 'something failed, goto sea_exit' -> 'first memory release for ea'
-> 'goto replay_again' -> 'second goto sea_exit before allocate memory
for ea' -> 'second memory release for ea resulted in double free'.

Re-initialie 'ea' to NULL near to the replay_again label, it can fix this
double free problem.

Fixes: 4f1fffa237 ("cifs: commands that are retried should have replay flag set")
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Su Hui <suhui@nfschina.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-10-16 00:25:54 -05:00
Shen Lichuan
e9f49feefb smb: client: Correct typos in multiple comments across various files
Fixed some confusing typos that were currently identified witch codespell,
the details are as follows:

-in the code comments:
fs/smb/client/cifsacl.h:58: inheritence ==> inheritance
fs/smb/client/cifsencrypt.c:242: origiginal ==> original
fs/smb/client/cifsfs.c:164: referece ==> reference
fs/smb/client/cifsfs.c:292: ned ==> need
fs/smb/client/cifsglob.h:779: initital ==> initial
fs/smb/client/cifspdu.h:784: altetnative ==> alternative
fs/smb/client/cifspdu.h:2409: conrol ==> control
fs/smb/client/cifssmb.c:1218: Expirement ==> Experiment
fs/smb/client/cifssmb.c:3021: conver ==> convert
fs/smb/client/cifssmb.c:3998: asterik ==> asterisk
fs/smb/client/file.c:2505: useable ==> usable
fs/smb/client/fs_context.h:263: timemout ==> timeout
fs/smb/client/misc.c:257: responsbility ==> responsibility
fs/smb/client/netmisc.c:1006: divisable ==> divisible
fs/smb/client/readdir.c:556: endianess ==> endianness
fs/smb/client/readdir.c:818: bu ==> by
fs/smb/client/smb2ops.c:2180: snaphots ==> snapshots
fs/smb/client/smb2ops.c:3586: otions ==> options
fs/smb/client/smb2pdu.c:2979: timestaps ==> timestamps
fs/smb/client/smb2pdu.c:4574: memmory ==> memory
fs/smb/client/smb2transport.c:699: origiginal ==> original
fs/smb/client/smbdirect.c:222: happenes ==> happens
fs/smb/client/smbdirect.c:1347: registartions ==> registrations
fs/smb/client/smbdirect.h:114: accoutning ==> accounting

Signed-off-by: Shen Lichuan <shenlichuan@vivo.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-10-02 17:52:24 -05:00
wangrong
a421e3fe0e smb: client: use actual path when queryfs
Due to server permission control, the client does not have access to
the shared root directory, but can access subdirectories normally, so
users usually mount the shared subdirectories directly. In this case,
queryfs should use the actual path instead of the root directory to
avoid the call returning an error (EACCES).

Signed-off-by: wangrong <wangrong@uniontech.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-10-01 21:47:16 -05:00
Enzo Matsumiya
b0abcd65ec smb: client: fix UAF in async decryption
Doing an async decryption (large read) crashes with a
slab-use-after-free way down in the crypto API.

Reproducer:
    # mount.cifs -o ...,seal,esize=1 //srv/share /mnt
    # dd if=/mnt/largefile of=/dev/null
    ...
    [  194.196391] ==================================================================
    [  194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110
    [  194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899
    [  194.197707]
    [  194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43
    [  194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014
    [  194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs]
    [  194.200032] Call Trace:
    [  194.200191]  <TASK>
    [  194.200327]  dump_stack_lvl+0x4e/0x70
    [  194.200558]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.200809]  print_report+0x174/0x505
    [  194.201040]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
    [  194.201352]  ? srso_return_thunk+0x5/0x5f
    [  194.201604]  ? __virt_addr_valid+0xdf/0x1c0
    [  194.201868]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.202128]  kasan_report+0xc8/0x150
    [  194.202361]  ? gf128mul_4k_lle+0xc1/0x110
    [  194.202616]  gf128mul_4k_lle+0xc1/0x110
    [  194.202863]  ghash_update+0x184/0x210
    [  194.203103]  shash_ahash_update+0x184/0x2a0
    [  194.203377]  ? __pfx_shash_ahash_update+0x10/0x10
    [  194.203651]  ? srso_return_thunk+0x5/0x5f
    [  194.203877]  ? crypto_gcm_init_common+0x1ba/0x340
    [  194.204142]  gcm_hash_assoc_remain_continue+0x10a/0x140
    [  194.204434]  crypt_message+0xec1/0x10a0 [cifs]
    [  194.206489]  ? __pfx_crypt_message+0x10/0x10 [cifs]
    [  194.208507]  ? srso_return_thunk+0x5/0x5f
    [  194.209205]  ? srso_return_thunk+0x5/0x5f
    [  194.209925]  ? srso_return_thunk+0x5/0x5f
    [  194.210443]  ? srso_return_thunk+0x5/0x5f
    [  194.211037]  decrypt_raw_data+0x15f/0x250 [cifs]
    [  194.212906]  ? __pfx_decrypt_raw_data+0x10/0x10 [cifs]
    [  194.214670]  ? srso_return_thunk+0x5/0x5f
    [  194.215193]  smb2_decrypt_offload+0x12a/0x6c0 [cifs]

This is because TFM is being used in parallel.

Fix this by allocating a new AEAD TFM for async decryption, but keep
the existing one for synchronous READ cases (similar to what is done
in smb3_calc_signature()).

Also remove the calls to aead_request_set_callback() and
crypto_wait_req() since it's always going to be a synchronous operation.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-26 18:14:48 -05:00
David Howells
307f77e7f5 cifs: Fix reversion of the iter in cifs_readv_receive().
cifs_read_iter_from_socket() copies the iterator that's passed in for the
socket to modify as and if it will, and then advances the original iterator
by the amount sent.  However, both callers revert the advancement (although
receive_encrypted_read() zeros beyond the iterator first).  The problem is,
though, that cifs_readv_receive() reverts by the original length, not the
amount transmitted which can cause an oops in iov_iter_revert().

Fix this by:

 (1) Remove the iov_iter_advance() from cifs_read_iter_from_socket().

 (2) Remove the iov_iter_revert() from both callers.  This fixes the bug in
     cifs_readv_receive().

 (3) In receive_encrypted_read(), if we didn't get back as much data as the
     buffer will hold, copy the iterator, advance the copy and use the copy
     to drive iov_iter_zero().

As a bonus, this gets rid of some unnecessary work.

This was triggered by generic/074 with the "-o sign" mount option.

Fixes: 3ee1a1fc39 ("cifs: Cut over to using netfslib")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-24 21:53:08 -05:00
Linus Torvalds
4e0373f1f9 24 smb3 client fixes, about half cleanup, and SMB3.1.1 compression improvements, and also fixes for special file types with sfu mount option
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Merge tag 'v6.12-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6

Pull smb client updates from Steve French:

 - cleanups (moving duplicated code, removing unused code etc)

 - fixes relating to "sfu" mount options (for better handling special
   file types)

 - SMB3.1.1 compression fixes/improvements

* tag 'v6.12-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6: (24 commits)
  smb: client: fix compression heuristic functions
  cifs: Update SFU comments about fifos and sockets
  cifs: Add support for creating SFU symlinks
  smb: use LIST_HEAD() to simplify code
  cifs: Recognize SFU socket type
  cifs: Show debug message when SFU Fifo type was detected
  cifs: Put explicit zero byte into SFU block/char types
  cifs: Add support for reading SFU symlink location
  cifs: Fix recognizing SFU symlinks
  smb: client: compress: fix an "illegal accesses" issue
  smb: client: compress: fix a potential issue of freeing an invalid pointer
  smb: client: compress: LZ77 code improvements cleanup
  smb: client: insert compression check/call on write requests
  smb3: mark compression as CONFIG_EXPERIMENTAL and fix missing compression operation
  cifs: Remove obsoleted declaration for cifs_dir_open
  smb: client: Use min() macro
  cifs: convert to use ERR_CAST()
  smb: add comment to STATUS_MCA_OCCURED
  smb: move SMB2 Status code to common header file
  smb: move some duplicate definitions to common/smbacl.h
  ...
2024-09-19 06:53:40 +02:00
Pali Rohár
37408843f2 cifs: Update SFU comments about fifos and sockets
In SFU mode, activated by -o sfu mount option is now also support for
creating new fifos and sockets.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-16 20:10:37 -05:00
Pali Rohár
41d3f256c6 cifs: Add support for creating SFU symlinks
Linux cifs client can already detect SFU symlinks and reads it content
(target location). But currently is not able to create new symlink. So
implement this missing support.

When 'sfu' mount option is specified and 'mfsymlinks' is not specified then
create new symlinks in SFU-style. This will provide full SFU compatibility
of symlinks when mounting cifs share with 'sfu' option. 'mfsymlinks' option
override SFU for better Apple compatibility as explained in fs_context.c
file in smb3_update_mnt_flags() function.

Extend __cifs_sfu_make_node() function, which now can handle also S_IFLNK
type and refactor structures passed to sync_write() in this function, by
splitting SFU type and SFU data from original combined struct win_dev as
combined fixed-length struct cannot be used for variable-length symlinks.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-16 20:10:34 -05:00
Linus Torvalds
35219bc5c7 vfs-6.12.netfs
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Merge tag 'vfs-6.12.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull netfs updates from Christian Brauner:
 "This contains the work to improve read/write performance for the new
  netfs library.

  The main performance enhancing changes are:

   - Define a structure, struct folio_queue, and a new iterator type,
     ITER_FOLIOQ, to hold a buffer as a replacement for ITER_XARRAY. See
     that patch for questions about naming and form.

     ITER_FOLIOQ is provided as a replacement for ITER_XARRAY. The
     problem with an xarray is that accessing it requires the use of a
     lock (typically the RCU read lock) - and this means that we can't
     supply iterate_and_advance() with a step function that might sleep
     (crypto for example) without having to drop the lock between pages.
     ITER_FOLIOQ is the iterator for a chain of folio_queue structs,
     where each folio_queue holds a small list of folios. A folio_queue
     struct is a simpler structure than xarray and is not subject to
     concurrent manipulation by the VM. folio_queue is used rather than
     a bvec[] as it can form lists of indefinite size, adding to one end
     and removing from the other on the fly.

   - Provide a copy_folio_from_iter() wrapper.

   - Make cifs RDMA support ITER_FOLIOQ.

   - Use folio queues in the write-side helpers instead of xarrays.

   - Add a function to reset the iterator in a subrequest.

   - Simplify the write-side helpers to use sheaves to skip gaps rather
     than trying to work out where gaps are.

   - In afs, make the read subrequests asynchronous, putting them into
     work items to allow the next patch to do progressive
     unlocking/reading.

   - Overhaul the read-side helpers to improve performance.

   - Fix the caching of a partial block at the end of a file.

   - Allow a store to be cancelled.

  Then some changes for cifs to make it use folio queues instead of
  xarrays for crypto bufferage:

   - Use raw iteration functions rather than manually coding iteration
     when hashing data.

   - Switch to using folio_queue for crypto buffers.

   - Remove the xarray bits.

  Make some adjustments to the /proc/fs/netfs/stats file such that:

   - All the netfs stats lines begin 'Netfs:' but change this to
     something a bit more useful.

   - Add a couple of stats counters to track the numbers of skips and
     waits on the per-inode writeback serialisation lock to make it
     easier to check for this as a source of performance loss.

  Miscellaneous work:

   - Ensure that the sb_writers lock is taken around
     vfs_{set,remove}xattr() in the cachefiles code.

   - Reduce the number of conditional branches in netfs_perform_write().

   - Move the CIFS_INO_MODIFIED_ATTR flag to the netfs_inode struct and
     remove cifs_post_modify().

   - Move the max_len/max_nr_segs members from netfs_io_subrequest to
     netfs_io_request as they're only needed for one subreq at a time.

   - Add an 'unknown' source value for tracing purposes.

   - Remove NETFS_COPY_TO_CACHE as it's no longer used.

   - Set the request work function up front at allocation time.

   - Use bh-disabling spinlocks for rreq->lock as cachefiles completion
     may be run from block-filesystem DIO completion in softirq context.

   - Remove fs/netfs/io.c"

* tag 'vfs-6.12.netfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (25 commits)
  docs: filesystems: corrected grammar of netfs page
  cifs: Don't support ITER_XARRAY
  cifs: Switch crypto buffer to use a folio_queue rather than an xarray
  cifs: Use iterate_and_advance*() routines directly for hashing
  netfs: Cancel dirty folios that have no storage destination
  cachefiles, netfs: Fix write to partial block at EOF
  netfs: Remove fs/netfs/io.c
  netfs: Speed up buffered reading
  afs: Make read subreqs async
  netfs: Simplify the writeback code
  netfs: Provide an iterator-reset function
  netfs: Use new folio_queue data type and iterator instead of xarray iter
  cifs: Provide the capability to extract from ITER_FOLIOQ to RDMA SGEs
  iov_iter: Provide copy_folio_from_iter()
  mm: Define struct folio_queue and ITER_FOLIOQ to handle a sequence of folios
  netfs: Use bh-disabling spinlocks for rreq->lock
  netfs: Set the request work function upon allocation
  netfs: Remove NETFS_COPY_TO_CACHE
  netfs: Reserve netfs_sreq_source 0 as unset/unknown
  netfs: Move max_len/max_nr_segs from netfs_io_subrequest to netfs_io_stream
  ...
2024-09-16 12:13:31 +02:00
Pali Rohár
bb68327053 cifs: Put explicit zero byte into SFU block/char types
SFU types IntxCHR and IntxBLK are 8 bytes with zero as last byte. Make it
explicit in memcpy and memset calls, so the zero byte is visible in the
code (and not hidden as string trailing nul byte).

It is important for reader to show the last byte for block and char types
because it differs from the last byte of symlink type (which has it 0x01).

Also it is important to show that the type is not nul-term string, but
rather 8 bytes (with some printable bytes).

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-15 10:42:45 -05:00
ChenXiaoSong
78181a5504 smb: move SMB2 Status code to common header file
There are only 4 different definitions between the client and server:

  - STATUS_SERVER_UNAVAILABLE: from client/smb2status.h
  - STATUS_FILE_NOT_AVAILABLE: from client/smb2status.h
  - STATUS_NO_PREAUTH_INTEGRITY_HASH_OVERLAP: from server/smbstatus.h
  - STATUS_INVALID_LOCK_RANGE: from server/smbstatus.h

Rename client/smb2status.h to common/smb2status.h, and merge the
2 different definitions of server to common header file.

Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-15 10:42:44 -05:00
ChenXiaoSong
3651487607 smb/client: rename cifs_ntsd to smb_ntsd
Preparation for moving acl definitions to new common header file.

Use the following shell command to rename:

  find fs/smb/client -type f -exec sed -i \
    's/struct cifs_ntsd/struct smb_ntsd/g' {} +

Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-15 10:42:44 -05:00
David Howells
a2906d3316
cifs: Switch crypto buffer to use a folio_queue rather than an xarray
Switch cifs from using an xarray to hold the transport crypto buffer to
using a folio_queue and use ITER_FOLIOQ rather than ITER_XARRAY.

This is part of the process of phasing out ITER_XARRAY.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Tom Talpey <tom@talpey.com>
cc: Enzo Matsumiya <ematsumiya@suse.de>
cc: linux-cifs@vger.kernel.org
Link: https://lore.kernel.org/r/20240814203850.2240469-25-dhowells@redhat.com/ # v2
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-12 12:20:42 +02:00
David Howells
ee4cdf7ba8
netfs: Speed up buffered reading
Improve the efficiency of buffered reads in a number of ways:

 (1) Overhaul the algorithm in general so that it's a lot more compact and
     split the read submission code between buffered and unbuffered
     versions.  The unbuffered version can be vastly simplified.

 (2) Read-result collection is handed off to a work queue rather than being
     done in the I/O thread.  Multiple subrequests can be processes
     simultaneously.

 (3) When a subrequest is collected, any folios it fully spans are
     collected and "spare" data on either side is donated to either the
     previous or the next subrequest in the sequence.

Notes:

 (*) Readahead expansion is massively slows down fio, presumably because it
     causes a load of extra allocations, both folio and xarray, up front
     before RPC requests can be transmitted.

 (*) RDMA with cifs does appear to work, both with SIW and RXE.

 (*) PG_private_2-based reading and copy-to-cache is split out into its own
     file and altered to use folio_queue.  Note that the copy to the cache
     now creates a new write transaction against the cache and adds the
     folios to be copied into it.  This allows it to use part of the
     writeback I/O code.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/20240814203850.2240469-20-dhowells@redhat.com/ # v2
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-12 12:20:41 +02:00
David Howells
ab85218910 netfs, cifs: Improve some debugging bits
Improve some debugging bits:

 (1) The netfslib _debug() macro doesn't need a newline in its format
     string.

 (2) Display the request debug ID and subrequest index in messages emitted
     in smb2_adjust_credits() to make it easier to reference in traces.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-03 10:17:51 -05:00
David Howells
91d1dfae46 cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region
Under certain conditions, the range to be cleared by FALLOC_FL_ZERO_RANGE
may only be buffered locally and not yet have been flushed to the server.
For example:

	xfs_io -f -t -c "pwrite -S 0x41 0 4k" \
		     -c "pwrite -S 0x42 4k 4k" \
		     -c "fzero 0 4k" \
		     -c "pread -v 0 8k" /xfstest.test/foo

will write two 4KiB blocks of data, which get buffered in the pagecache,
and then fallocate() is used to clear the first 4KiB block on the server -
but we don't flush the data first, which means the EOF position on the
server is wrong, and so the FSCTL_SET_ZERO_DATA RPC fails (and xfs_io
ignores the error), but then when we try to read it, we see the old data.

Fix this by preflushing any part of the target region that above the
server's idea of the EOF position to force the server to update its EOF
position.

Note, however, that we don't want to simply expand the file by moving the
EOF before doing the FSCTL_SET_ZERO_DATA[*] because someone else might see
the zeroed region or if the RPC fails we then have to try to clean it up or
risk getting corruption.

[*] And we have to move the EOF first otherwise FSCTL_SET_ZERO_DATA won't
do what we want.

This fixes the generic/008 xfstest.

[!] Note: A better way to do this might be to split the operation into two
parts: we only do FSCTL_SET_ZERO_DATA for the part of the range below the
server's EOF and then, if that worked, invalidate the buffered pages for the
part above the range.

Fixes: 6b69040247 ("cifs/smb3: Fix data inconsistent when zero file range")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
cc: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
cc: Pavel Shilovsky <pshilov@microsoft.com>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-08-28 16:52:17 -05:00
David Howells
6a5dcd4877 cifs: Fix lack of credit renegotiation on read retry
When netfslib asks cifs to issue a read operation, it prefaces this with a
call to ->clamp_length() which cifs uses to negotiate credits, providing
receive capacity on the server; however, in the event that a read op needs
reissuing, netfslib doesn't call ->clamp_length() again as that could
shorten the subrequest, leaving a gap.

This causes the retried read to be done with zero credits which causes the
server to reject it with STATUS_INVALID_PARAMETER.  This is a problem for a
DIO read that is requested that would go over the EOF.  The short read will
be retried, causing EINVAL to be returned to the user when it fails.

Fix this by making cifs_req_issue_read() negotiate new credits if retrying
(NETFS_SREQ_RETRYING now gets set in the read side as well as the write
side in this instance).

This isn't sufficient, however: the new credits might not be sufficient to
complete the remainder of the read, so also add an additional field,
rreq->actual_len, that holds the actual size of the op we want to perform
without having to alter subreq->len.

We then rely on repeated short reads being retried until we finish the read
or reach the end of file and make a zero-length read.

Also fix a couple of places where the subrequest start and length need to
be altered by the amount so far transferred when being used.

Fixes: 69c3c023af ("cifs: Implement netfslib hooks")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-08-28 07:47:36 -05:00
David Howells
416871f4fb cifs: Fix FALLOC_FL_PUNCH_HOLE support
The cifs filesystem doesn't quite emulate FALLOC_FL_PUNCH_HOLE correctly
(note that due to lack of protocol support, it can't actually implement it
directly).  Whilst it will (partially) invalidate dirty folios in the
pagecache, it doesn't write them back first, and so the EOF marker on the
server may be lower than inode->i_size.

This presents a problem, however, as if the punched hole invalidates the
tail of the locally cached dirty data, writeback won't know it needs to
move the EOF over to account for the hole punch (which isn't supposed to
move the EOF).  We could just write zeroes over the punched out region of
the pagecache and write that back - but this is supposed to be a
deallocatory operation.

Fix this by manually moving the EOF over on the server after the operation
if the hole punched would corrupt it.

Note that the FSCTL_SET_ZERO_DATA RPC and the setting of the EOF should
probably be compounded to stop a third party interfering (or, at least,
massively reduce the chance).

This was reproducible occasionally by using fsx with the following script:

	truncate 0x0 0x375e2 0x0
	punch_hole 0x2f6d3 0x6ab5 0x375e2
	truncate 0x0 0x3a71f 0x375e2
	mapread 0xee05 0xcf12 0x3a71f
	write 0x2078e 0x5604 0x3a71f
	write 0x3ebdf 0x1421 0x3a71f *
	punch_hole 0x379d0 0x8630 0x40000 *
	mapread 0x2aaa2 0x85b 0x40000
	fallocate 0x1b401 0x9ada 0x40000
	read 0x15f2 0x7d32 0x40000
	read 0x32f37 0x7a3b 0x40000 *

The second "write" should extend the EOF to 0x40000, and the "punch_hole"
should operate inside of that - but that depends on whether the VM gets in
and writes back the data first.  If it doesn't, the file ends up 0x3a71f in
size, not 0x40000.

Fixes: 31742c5a33 ("enable fallocate punch hole ("fallocate -p") for SMB3")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-08-25 09:06:25 -05:00
Stefan Metzmacher
b608e2c318 smb/client: remove unused rq_iter_size from struct smb_rqst
Reviewed-by: David Howells <dhowells@redhat.com>
Fixes: d08089f649 ("cifs: Change the I/O paths to use an iterator rather than a page list")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-08-25 09:06:25 -05:00
Steve French
6629f87b97 smb3: add four dynamic tracepoints for copy_file_range and reflink
Add more dynamic tracepoints to help debug copy_file_range (copychunk)
and clone_range ("duplicate extents").  These are tracepoints for
entering the function and completing without error. For example:

  "trace-cmd record -e smb3_copychunk_enter -e smb3_copychunk_done"

or

  "trace-cmd record -e smb3_clone_enter -e smb3_clone_done"

Here is sample output:

       TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION
         | |         |   |||||     |         |
       cp-5964    [005] .....  2176.168977: smb3_clone_enter:
         xid=17 sid=0xeb275be4 tid=0x7ffa7cdb source fid=0x1ed02e15
         source offset=0x0 target fid=0x1ed02e15 target offset=0x0
         len=0xa0000
       cp-5964    [005] .....  2176.170668: smb3_clone_done:
         xid=17 sid=0xeb275be4 tid=0x7ffa7cdb source fid=0x1ed02e15
         source offset=0x0 target fid=0x1ed02e15 target offset=0x0
         len=0xa0000

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-07-26 12:34:41 -05:00
Steve French
5779d398db smb3: add dynamic tracepoint for reflink errors
There are cases where debugging clone_range ("smb2_duplicate_extents"
function) and in the future copy_range ("smb2_copychunk_range") can
be helpful. Add dynamic trace points for any errors in clone, and
a followon patch will add them for copychunk.

  "trace-cmd record -e smb3_clone_err"

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-07-26 12:34:19 -05:00
David Howells
519be98971 cifs: Add a tracepoint to track credits involved in R/W requests
Add a tracepoint to track the credit changes and server in_flight value
involved in the lifetime of a R/W request, logging it against the
request/subreq debugging ID.  This requires the debugging IDs to be
recorded in the cifs_credits struct.

The tracepoint can be enabled with:

	echo 1 >/sys/kernel/debug/tracing/events/cifs/smb3_rw_credits/enable

Also add a three-state flag to struct cifs_credits to note if we're
interested in determining when the in_flight contribution ends and, if so,
to track whether we've decremented the contribution yet.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-07-19 11:08:57 -05:00
Steve French
518549c120 cifs: fix creating sockets when using sfu mount options
When running fstest generic/423 with sfu mount option, it
was being skipped due to inability to create sockets:

  generic/423  [not run] cifs does not support mknod/mkfifo

which can also be easily reproduced with their af_unix tool:

  ./src/af_unix /mnt1/socket-two bind: Operation not permitted

Fix sfu mount option to allow creating and reporting sockets.

Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-05-31 10:55:15 -05:00
David Howells
93a4315512 cifs: Fix missing set of remote_i_size
Occasionally, the generic/001 xfstest will fail indicating corruption in
one of the copy chains when run on cifs against a server that supports
FSCTL_DUPLICATE_EXTENTS_TO_FILE (eg. Samba with a share on btrfs).  The
problem is that the remote_i_size value isn't updated by cifs_setsize()
when called by smb2_duplicate_extents(), but i_size *is*.

This may cause cifs_remap_file_range() to then skip the bit after calling
->duplicate_extents() that sets sizes.

Fix this by calling netfs_resize_file() in smb2_duplicate_extents() before
calling cifs_setsize() to set i_size.

This means we don't then need to call netfs_resize_file() upon return from
->duplicate_extents(), but we also fix the test to compare against the pre-dup
inode size.

[Note that this goes back before the addition of remote_i_size with the
netfs_inode struct.  It should probably have been setting cifsi->server_eof
previously.]

Fixes: cfc63fc812 ("smb3: fix cached file size problems in duplicate extents (reflink)")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-05-24 16:05:56 -05:00
David Howells
8a16072335 cifs: Fix smb3_insert_range() to move the zero_point
Fix smb3_insert_range() to move the zero_point over to the new EOF.
Without this, generic/147 fails as reads of data beyond the old EOF point
return zeroes.

Fixes: 3ee1a1fc39 ("cifs: Cut over to using netfslib")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-05-24 16:04:36 -05:00
David Howells
56257334e8 cifs: Make wait_mtu_credits take size_t args
Make the wait_mtu_credits functions use size_t for the size and num
arguments rather than unsigned int as netfslib uses size_t/ssize_t for
arguments and return values to allow for extra capacity.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-cachefs@redhat.com
cc: netfs@lists.linux.dev
cc: linux-mm@kvack.org
2024-05-01 18:08:19 +01:00
David Howells
ab58fbdeeb cifs: Use more fields from netfs_io_subrequest
Use more fields from netfs_io_subrequest instead of those incorporated into
cifs_io_subrequest from cifs_readdata and cifs_writedata.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
2024-05-01 18:08:19 +01:00
David Howells
753b67eb63 cifs: Replace cifs_readdata with a wrapper around netfs_io_subrequest
Netfslib has a facility whereby the allocation for netfs_io_subrequest can
be increased to so that filesystem-specific data can be tagged on the end.

Prepare to use this by making a struct, cifs_io_subrequest, that wraps
netfs_io_subrequest, and absorb struct cifs_readdata into it.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
2024-05-01 18:08:18 +01:00
David Howells
afc23febd5 cifs: Add tracing for the cifs_tcon struct refcounting
Add tracing for the refcounting/lifecycle of the cifs_tcon struct, marking
different events with different labels and giving each tcon its own debug
ID so that the tracelines corresponding to individual tcons can be
distinguished.  This can be enabled with:

	echo 1 >/sys/kernel/debug/tracing/events/cifs/smb3_tcon_ref/enable

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-19 16:02:09 -05:00
Paulo Alcantara
c6ff459037 smb: client: instantiate when creating SFU files
In cifs_sfu_make_node(), on success, instantiate rather than leave it
with dentry unhashed negative to support callers that expect mknod(2)
to always instantiate.

This fixes the following test case:

  mount.cifs //srv/share /mnt -o ...,sfu
  mkfifo /mnt/fifo
  ./xfstests/ltp/growfiles -b -W test -e 1 -u -i 0 -L 30 /mnt/fifo
  ...
  BUG: unable to handle page fault for address: 000000034cec4e58
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 1 PREEMPT SMP PTI
  CPU: 0 PID: 138098 Comm: growfiles Kdump: loaded Not tainted
  5.14.0-436.3987_1240945149.el9.x86_64 #1
  Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
  RIP: 0010:_raw_callee_save__kvm_vcpu_is_preempted+0x0/0x20
  Code: e8 15 d9 61 00 e9 63 ff ff ff 41 bd ea ff ff ff e9 58 ff ff ff e8
  d0 71 c0 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 04
  fd 60 2b c1 99 80 b8 90 50 03 00 00 0f 95 c0 c3 cc cc cc
  RSP: 0018:ffffb6a143cf7cf8 EFLAGS: 00010206
  RAX: ffff8a9bc30fb038 RBX: ffff8a9bc666a200 RCX: ffff8a9cc0260000
  RDX: 00000000736f622e RSI: ffff8a9bc30fb038 RDI: 000000007665645f
  RBP: ffffb6a143cf7d70 R08: 0000000000001000 R09: 0000000000000001
  R10: 0000000000000001 R11: 0000000000000000 R12: ffff8a9bc666a200
  R13: 0000559a302a12b0 R14: 0000000000001000 R15: 0000000000000000
  FS: 00007fbed1dbb740(0000) GS:ffff8a9cf0000000(0000)
  knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 000000034cec4e58 CR3: 0000000128ec6006 CR4: 0000000000770ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
   <TASK>
   ? show_trace_log_lvl+0x1c4/0x2df
   ? show_trace_log_lvl+0x1c4/0x2df
   ? __mutex_lock.constprop.0+0x5f7/0x6a0
   ? __die_body.cold+0x8/0xd
   ? page_fault_oops+0x134/0x170
   ? exc_page_fault+0x62/0x150
   ? asm_exc_page_fault+0x22/0x30
   ? _pfx_raw_callee_save__kvm_vcpu_is_preempted+0x10/0x10
   __mutex_lock.constprop.0+0x5f7/0x6a0
   ? __mod_memcg_lruvec_state+0x84/0xd0
   pipe_write+0x47/0x650
   ? do_anonymous_page+0x258/0x410
   ? inode_security+0x22/0x60
   ? selinux_file_permission+0x108/0x150
   vfs_write+0x2cb/0x410
   ksys_write+0x5f/0xe0
   do_syscall_64+0x5c/0xf0
   ? syscall_exit_to_user_mode+0x22/0x40
   ? do_syscall_64+0x6b/0xf0
   ? sched_clock_cpu+0x9/0xc0
   ? exc_page_fault+0x62/0x150
   entry_SYSCALL_64_after_hwframe+0x6e/0x76

Cc: stable@vger.kernel.org
Fixes: 72bc63f5e2 ("smb3: fix creating FIFOs when mounting with "sfu" mount option")
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-11 16:03:40 -05:00
Paulo Alcantara
63981561ff smb: client: fix potential UAF in smb2_is_network_name_deleted()
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-03 14:45:06 -05:00
Ritvik Budhiraja
173217bd73 smb3: retrying on failed server close
In the current implementation, CIFS close sends a close to the
server and does not check for the success of the server close.
This patch adds functionality to check for server close return
status and retries in case of an EBUSY or EAGAIN error.

This can help avoid handle leaks

Cc: stable@vger.kernel.org
Signed-off-by: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-03 14:43:24 -05:00
Justin Stitt
ebd9779683 smb: client: replace deprecated strncpy with strscpy
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.

In cifssmb.c:
Using strncpy with a length argument equal to strlen(src) is generally
dangerous because it can cause string buffers to not be NUL-terminated.
In this case, however, there was extra effort made to ensure the buffer
was NUL-terminated via a manual NUL-byte assignment. In an effort to rid
the kernel of strncpy() use, let's swap over to using strscpy() which
guarantees NUL-termination on the destination buffer.

To handle the case where ea_name is NULL, let's use the ?: operator to
substitute in an empty string, thereby allowing strscpy to still
NUL-terminate the destintation string.

Interesting note: this flex array buffer may go on to also have some
value encoded after the NUL-termination:
|	if (ea_value_len)
|		memcpy(parm_data->list.name + name_len + 1,
|			ea_value, ea_value_len);

Now for smb2ops.c and smb2transport.c:
Both of these cases are simple, strncpy() is used to copy string
literals which have a length less than the destination buffer's size. We
can simply swap in the new 2-argument version of strscpy() introduced in
Commit e6584c3964 ("string: Allow 2-argument strscpy()").

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-03-31 17:35:14 -05:00
Shyam Prasad N
13c0a74747 cifs: make sure server interfaces are requested only for SMB3+
Some code paths for querying server interfaces make a false
assumption that it will only get called for SMB3+. Since this
function now can get called from a generic code paths, the correct
thing to do is to have specific handler for this functionality
per SMB dialect, and call this handler.

This change adds such a handler and implements this handler only
for SMB 3.0 and 3.1.1.

Cc: stable@vger.kernel.org
Cc: Jan Čermák <sairon@sairon.cz>
Reported-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-03-14 13:54:27 -05:00
Paulo Alcantara
5a4b09ecf8 smb: client: add support for WSL reparse points
Add support for creating special files via WSL reparse points when
using 'reparse=wsl' mount option.  They're faster than NFS reparse
points because they don't require extra roundtrips to figure out what
->d_type a specific dirent is as such information is already stored in
query dir responses and then making getdents() calls faster.

Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-03-10 19:33:58 -05:00
Paulo Alcantara
c520ba7573 smb: client: move most of reparse point handling code to common file
In preparation to add support for creating special files also via WSL
reparse points in next commits.

Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-03-10 19:33:57 -05:00
Paulo Alcantara
8bde59b20d smb: client: handle path separator of created SMB symlinks
Convert path separator to CIFS_DIR_SEP(cifs_sb) from symlink target
before sending it over the wire otherwise the created SMB symlink may
become innaccesible from server side.

Fixes: 514d793e27 ("smb: client: allow creating symlinks via reparse points")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-02-12 12:47:21 -06:00
Shyam Prasad N
79520587fe cifs: update the same create_guid on replay
File open requests made to the server contain a
CreateGuid, which is used by the server to identify
the open request. If the same request needs to be
replayed, it needs to be sent with the same CreateGuid
in the durable handle v2 context.

Without doing so, we could end up leaking handles on
the server when:
1. multichannel is used AND
2. connection goes down, but not for all channels

This is because the replayed open request would have a
new CreateGuid and the server will treat this as a new
request and open a new handle.

This change fixes this by reusing the existing create_guid
stored in the cached fid struct.

REF: MS-SMB2 4.9 Replay Create Request on an Alternate Channel

Fixes: 4f1fffa237 ("cifs: commands that are retried should have replay flag set")
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-02-11 19:07:08 -06:00
Dan Carpenter
cffe487026 cifs: fix underflow in parse_server_interfaces()
In this loop, we step through the buffer and after each item we check
if the size_left is greater than the minimum size we need.  However,
the problem is that "bytes_left" is type ssize_t while sizeof() is type
size_t.  That means that because of type promotion, the comparison is
done as an unsigned and if we have negative bytes left the loop
continues instead of ending.

Fixes: fe856be475 ("CIFS: parse and store info on iface queries")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-02-11 19:07:08 -06:00
Shyam Prasad N
4f1fffa237 cifs: commands that are retried should have replay flag set
MS-SMB2 states that the header flag SMB2_FLAGS_REPLAY_OPERATION
needs to be set when a command needs to be retried, so that
the server is aware that this is a replay for an operation that
appeared before.

This can be very important, for example, for state changing
operations and opens which get retried following a reconnect;
since the client maybe unaware of the status of the previous
open.

This is particularly important for multichannel scenario, since
disconnection of one connection does not mean that the session
is lost. The requests can be replayed on another channel.

This change also makes use of exponential back-off before replays
and also limits the number of retries to "retrans" mount option
value.

Also, this change does not modify the read/write codepath.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-23 20:23:29 -06:00
David Howells
966cc171c8 cifs: Share server EOF pos with netfslib
Use cifsi->netfs_ctx.remote_i_size instead of cifsi->server_eof so that
netfslib can refer to it to.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-23 18:59:05 -06:00
Shyam Prasad N
78e727e58e cifs: update iface_last_update on each query-and-update
iface_last_update was an unused field when it was introduced.
Later, when we had periodic update of server interface list,
this field was used regularly to decide when to update next.

However, with the new logic of updating the interfaces, it
becomes crucial that this field be updated whenever
parse_server_interfaces runs successfully.

This change updates this field when either the server does
not support query of interfaces; so that we do not query
the interfaces repeatedly. It also updates the field when
the function reaches the end.

Fixes: aa45dadd34 ("cifs: change iface_list from array to sorted linked list")
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-19 10:33:21 -06:00
Shyam Prasad N
f591062bdb cifs: handle servers that still advertise multichannel after disabling
Some servers like Azure SMB servers always advertise multichannel
capability in server capabilities list. Such servers return error
STATUS_NOT_IMPLEMENTED for ioctl calls to query server interfaces,
and expect clients to consider that as a sign that they do not support
multichannel.

We already handled this at mount time. Soon after the tree connect,
we query server interfaces. And when server returned STATUS_NOT_IMPLEMENTED,
we kept interface list as empty. When cifs_try_adding_channels gets
called, it would not find any interfaces, so will not add channels.

For the case where an active multichannel mount exists, and multichannel
is disabled by such a server, this change will now allow the client
to disable secondary channels on the mount. It will check the return
status of query server interfaces call soon after a tree reconnect.
If the return status is EOPNOTSUPP, then instead of the check to add
more channels, we'll disable the secondary channels instead.

For better code reuse, this change also moves the common code for
disabling multichannel to a helper function.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-19 10:33:17 -06:00
Paulo Alcantara
8a3c4e44c2 cifs: get rid of dup length check in parse_reparse_point()
smb2_compound_op(SMB2_OP_GET_REPARSE) already checks if ioctl response
has a valid reparse data buffer's length, so there's no need to check
it again in parse_reparse_point().

In order to get rid of duplicate check, validate reparse data buffer's
length also in cifs_query_reparse_point().

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-07 21:18:00 -06:00
David Howells
6ebfede8d5 cifs: Pass unbyteswapped eof value into SMB2_set_eof()
Change SMB2_set_eof() to take eof as CPU order rather than __le64 and pass
it directly rather than by pointer.  This moves the conversion down into
SMB_set_eof() rather than all of its callers and means we don't need to
undo it for the traceline.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-07 15:46:06 -06:00
Paulo Alcantara
3ded18a9e9 smb: client: cleanup smb2_query_reparse_point()
Use smb2_compound_op() with SMB2_OP_GET_REPARSE to get reparse point.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-07 15:46:06 -06:00