ksmbd: clear RENAME_NOREPLACE before calling vfs_rename

File overwrite case is explicitly handled, so it is not necessary to
pass RENAME_NOREPLACE to vfs_rename.

Clearing the flag fixes rename operations when the share is a ntfs-3g
mount. The latter uses an older version of fuse with no support for
flags in the ->rename op.

Cc: stable@vger.kernel.org
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: replace generic_fillattr with vfs_getattr

generic_fillattr should not be used outside of ->getattr
implementations.

Use vfs_getattr instead, and adapt functions to return an
error code to the caller.

Cc: stable@vger.kernel.org
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb/server: adapt to breakup of struct file_lock

Most of the existing APIs have remained the same, but subsystems that
access file_lock fields directly need to reach into struct
file_lock_core now.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-45-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

filelock: split common fields into struct file_lock_core

In a future patch, we're going to split file leases into their own
structure. Since a lot of the underlying machinery uses the same fields
move those into a new file_lock_core, and embed that inside struct
file_lock.

For now, add some macros to ensure that we can continue to build while
the conversion is in progress.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-17-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

smb/server: convert to using new filelock helpers

Convert to using the new file locking helper functions.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-15-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ksmbd: vfs: fix all kernel-doc warnings

Fix all kernel-doc warnings in vfs.c:

vfs.c:54: warning: Function parameter or member 'parent' not described in 'ksmbd_vfs_lock_parent'
vfs.c:54: warning: Function parameter or member 'child' not described in 'ksmbd_vfs_lock_parent'
vfs.c:54: warning: No description found for return value of 'ksmbd_vfs_lock_parent'
vfs.c:372: warning: Function parameter or member 'fp' not described in 'ksmbd_vfs_read'
vfs.c:372: warning: Excess function parameter 'fid' description in 'ksmbd_vfs_read'
vfs.c:489: warning: Function parameter or member 'fp' not described in 'ksmbd_vfs_write'
vfs.c:489: warning: Excess function parameter 'fid' description in 'ksmbd_vfs_write'
vfs.c:555: warning: Function parameter or member 'path' not described in 'ksmbd_vfs_getattr'
vfs.c:555: warning: Function parameter or member 'stat' not described in 'ksmbd_vfs_getattr'
vfs.c:555: warning: Excess function parameter 'work' description in 'ksmbd_vfs_getattr'
vfs.c:555: warning: Excess function parameter 'fid' description in 'ksmbd_vfs_getattr'
vfs.c:555: warning: Excess function parameter 'attrs' description in 'ksmbd_vfs_getattr'
vfs.c:572: warning: Function parameter or member 'p_id' not described in 'ksmbd_vfs_fsync'
vfs.c:595: warning: Function parameter or member 'work' not described in 'ksmbd_vfs_remove_file'
vfs.c:595: warning: Function parameter or member 'path' not described in 'ksmbd_vfs_remove_file'
vfs.c:595: warning: Excess function parameter 'name' description in 'ksmbd_vfs_remove_file'
vfs.c:633: warning: Function parameter or member 'work' not described in 'ksmbd_vfs_link'
vfs.c:805: warning: Function parameter or member 'fp' not described in 'ksmbd_vfs_truncate'
vfs.c:805: warning: Excess function parameter 'fid' description in 'ksmbd_vfs_truncate'
vfs.c:846: warning: Excess function parameter 'size' description in 'ksmbd_vfs_listxattr'
vfs.c:953: warning: Function parameter or member 'option' not described in 'ksmbd_vfs_set_fadvise'
vfs.c:953: warning: Excess function parameter 'options' description in 'ksmbd_vfs_set_fadvise'
vfs.c:1167: warning: Function parameter or member 'um' not described in 'ksmbd_vfs_lookup_in_dir'
vfs.c:1203: warning: Function parameter or member 'work' not described in 'ksmbd_vfs_kern_path_locked'
vfs.c:1641: warning: No description found for return value of 'ksmbd_vfs_init_kstat'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <sfrench@samba.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

rename(): avoid a deadlock in the case of parents having no common ancestor

... and fix the directory locking documentation and proof of correctness.
Holding ->s_vfs_rename_mutex *almost* prevents ->d_parent changes; the
case where we really don't want it is splicing the root of disconnected
tree to somewhere.

In other words, ->s_vfs_rename_mutex is sufficient to stabilize "X is an
ancestor of Y" only if X and Y are already in the same tree. Otherwise
it can go from false to true, and one can construct a deadlock on that.

Make lock_two_directories() report an error in such case and update the
callers of lock_rename()/lock_rename_child() to handle such errors.

And yes, such conditions are not impossible to create ;-/

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ksmbd: lazy v2 lease break on smb2_write()

Don't immediately send directory lease break notification on smb2_write().
Instead, It postpones it until smb2_close().

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: separately allocate ci per dentry

xfstests generic/002 test fail when enabling smb2 leases feature.
This test create hard link file, but removeal failed.
ci has a file open count to count file open through the smb client,
but in the case of hard link files, The allocation of ci per inode
cause incorrectly open count for file deletion. This patch allocate
ci per dentry to counts open counts for hard link.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix possible deadlock in smb2_open

[ 8743.393379] ======================================================
[ 8743.393385] WARNING: possible circular locking dependency detected
[ 8743.393391] 6.4.0-rc1+ #11 Tainted: G OE
[ 8743.393397] ------------------------------------------------------
[ 8743.393402] kworker/0:2/12921 is trying to acquire lock:
[ 8743.393408] ffff888127a14460 (sb_writers#8){.+.+}-{0:0}, at: ksmbd_vfs_setxattr+0x3d/0xd0 [ksmbd]
[ 8743.393510]
but task is already holding lock:
[ 8743.393515] ffff8880360d97f0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: ksmbd_vfs_kern_path_locked+0x181/0x670 [ksmbd]
[ 8743.393618]
which lock already depends on the new lock.

[ 8743.393623]
the existing dependency chain (in reverse order) is:
[ 8743.393628]
-> #1 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}:
[ 8743.393648] down_write_nested+0x9a/0x1b0
[ 8743.393660] filename_create+0x128/0x270
[ 8743.393670] do_mkdirat+0xab/0x1f0
[ 8743.393680] __x64_sys_mkdir+0x47/0x60
[ 8743.393690] do_syscall_64+0x5d/0x90
[ 8743.393701] entry_SYSCALL_64_after_hwframe+0x72/0xdc
[ 8743.393711]
-> #0 (sb_writers#8){.+.+}-{0:0}:
[ 8743.393728] __lock_acquire+0x2201/0x3b80
[ 8743.393737] lock_acquire+0x18f/0x440
[ 8743.393746] mnt_want_write+0x5f/0x240
[ 8743.393755] ksmbd_vfs_setxattr+0x3d/0xd0 [ksmbd]
[ 8743.393839] ksmbd_vfs_set_dos_attrib_xattr+0xcc/0x110 [ksmbd]
[ 8743.393924] compat_ksmbd_vfs_set_dos_attrib_xattr+0x39/0x50 [ksmbd]
[ 8743.394010] smb2_open+0x3432/0x3cc0 [ksmbd]
[ 8743.394099] handle_ksmbd_work+0x2c9/0x7b0 [ksmbd]
[ 8743.394187] process_one_work+0x65a/0xb30
[ 8743.394198] worker_thread+0x2cf/0x700
[ 8743.394209] kthread+0x1ad/0x1f0
[ 8743.394218] ret_from_fork+0x29/0x50

This patch add mnt_want_write() above parent inode lock and remove
nested mnt_want_write calls in smb2_open().

Fixes: 40b268d384a2 ("ksmbd: add mnt_want_write to ksmbd vfs functions")
Cc: stable@vger.kernel.org
Reported-by: Marios Makassikis <mmakassikis@freebox.fr>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix kernel-doc comment of ksmbd_vfs_kern_path_locked()

Fix argument list that the kdoc format and script verified in
ksmbd_vfs_kern_path_locked().

fs/smb/server/vfs.c:1207: warning: Function parameter or member 'parent_path'
not described in 'ksmbd_vfs_kern_path_locked'

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix recursive locking in vfs helpers

Running smb2.rename test from Samba smbtorture suite against a kernel built
with lockdep triggers a "possible recursive locking detected" warning.

This is because mnt_want_write() is called twice with no mnt_drop_write()
in between:
-> ksmbd_vfs_mkdir()
-> ksmbd_vfs_kern_path_create()
-> kern_path_create()
-> filename_create()
-> mnt_want_write()
-> mnt_want_write()

Fix this by removing the mnt_want_write/mnt_drop_write calls from vfs
helpers that call kern_path_create().

Full lockdep trace below:

============================================
WARNING: possible recursive locking detected
6.6.0-rc5 #775 Not tainted
--------------------------------------------
kworker/1:1/32 is trying to acquire lock:
ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: ksmbd_vfs_mkdir+0xe1/0x410

but task is already holding lock:
ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: filename_create+0xb6/0x260

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

CPU0
----
lock(sb_writers#5);
lock(sb_writers#5);

*** DEADLOCK ***

May be due to missing lock nesting notation

4 locks held by kworker/1:1/32:
#0: ffff8880064e4138 ((wq_completion)ksmbd-io){+.+.}-{0:0}, at: process_one_work+0x40e/0x980
#1: ffff888005b0fdd0 ((work_completion)(&work->work)){+.+.}-{0:0}, at: process_one_work+0x40e/0x980
#2: ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: filename_create+0xb6/0x260
#3: ffff8880057ce760 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x123/0x260

Cc: stable@vger.kernel.org
Fixes: 40b268d384a2 ("ksmbd: add mnt_want_write to ksmbd vfs functions")
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix kernel-doc comment of ksmbd_vfs_setxattr()

Fix argument list that the kdoc format and script verified in
ksmbd_vfs_setxattr().

fs/smb/server/vfs.c:929: warning: Function parameter or member 'path'
not described in 'ksmbd_vfs_setxattr'

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: add support for read compound

MacOS sends a compound request including read to the server
(e.g. open-read-close). So far, ksmbd has not handled read as
a compound request. For compatibility between ksmbd and an OS that
supports SMB, This patch provides compound support for read requests.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

fs: pass the request_mask to generic_fillattr

generic_fillattr just fills in the entire stat struct indiscriminately
today, copying data from the inode. There is at least one attribute
(STATX_CHANGE_COOKIE) that can have side effects when it is reported,
and we're looking at adding more with the addition of multigrain
timestamps.

Add a request_mask argument to generic_fillattr and have most callers
just pass in the value that is passed to getattr. Have other callers
(e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
STATX_CHANGE_COOKIE into generic_fillattr.

Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Paulo Alcantara (SUSE)" <pc@manguebit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

ksmbd: check if a mount point is crossed during path lookup

Since commit 74d7970febf7 ("ksmbd: fix racy issue from using ->d_parent and
->d_name"), ksmbd can not lookup cross mount points. If last component is
a cross mount point during path lookup, check if it is crossed to follow it
down. And allow path lookup to cross a mount point when a crossmnt
parameter is set to 'yes' in smb.conf.

Cc: stable@vger.kernel.org
Fixes: 74d7970febf7 ("ksmbd: fix racy issue from using ->d_parent and ->d_name")
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: Fix unsigned expression compared with zero

The return value of the ksmbd_vfs_getcasexattr() is signed.
However, the return value is being assigned to an unsigned
variable and subsequently recasted, causing warnings. Use
a signed type.

Signed-off-by: Wang Ming <machel@vivo.com>
Acked-by: Tom Talpey <tom@talpey.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: use kvzalloc instead of kvmalloc

Use kvzalloc instead of kvmalloc.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: Change the return value of ksmbd_vfs_query_maximal_access to void

The return value of ksmbd_vfs_query_maximal_access is meaningless,
it is better to modify it to void.

Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: return a literal instead of 'err' in ksmbd_vfs_kern_path_locked()

Return a literal instead of 'err' in ksmbd_vfs_kern_path_locked().

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: add mnt_want_write to ksmbd vfs functions

ksmbd is doing write access using vfs helpers. There are the cases that
mnt_want_write() is not called in vfs helper. This patch add missing
mnt_want_write() to ksmbd vfs functions.

Cc: stable@vger.kernel.org
Cc: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix posix_acls and acls dereferencing possible ERR_PTR()

Dan reported the following error message:

fs/smb/server/smbacl.c:1296 smb_check_perm_dacl()
error: 'posix_acls' dereferencing possible ERR_PTR()
fs/smb/server/vfs.c:1323 ksmbd_vfs_make_xattr_posix_acl()
error: 'posix_acls' dereferencing possible ERR_PTR()
fs/smb/server/vfs.c:1830 ksmbd_vfs_inherit_posix_acl()
error: 'acls' dereferencing possible ERR_PTR()

__get_acl() returns a mix of error pointers and NULL. This change it
with IS_ERR_OR_NULL().

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: call putname after using the last component

last component point filename struct. Currently putname is called after
vfs_path_parent_lookup(). And then last component is used for
lookup_one_qstr_excl(). name in last component is freed by previous
calling putname(). And It cause file lookup failure when testing
generic/464 test of xfstest.

Fixes: 74d7970febf7 ("ksmbd: fix racy issue from using ->d_parent and ->d_name")
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

ksmbd: fix uninitialized pointer read in ksmbd_vfs_rename()

Uninitialized rd.delegated_inode can be used in vfs_rename().
Fix this by setting rd.delegated_inode to NULL to avoid the uninitialized
read.

Fixes: 74d7970febf7 ("ksmbd: fix racy issue from using ->d_parent and ->d_name")
Reported-by: Coverity Scan <scan-admin@coverity.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb: move client and server files to common directory fs/smb

Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko
and helper modules) to new fs/smb subdirectory:

fs/cifs --> fs/smb/client
fs/ksmbd --> fs/smb/server
fs/smbfs_common --> fs/smb/common

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>