Change notification is a commonly supported feature by most servers,
but the current ioctl to request notification when a directory is
changed does not return the information about what changed
(even though it is returned by the server in the SMB3 change
notify response), it simply returns when there is a change.
This ioctl improves upon CIFS_IOC_NOTIFY by returning the notify
information structure which includes the name of the file(s) that
changed and why. See MS-SMB2 2.2.35 for details on the individual
filter flags and the file_notify_information structure returned.
To use this simply pass in the following (with enough space
to fit at least one file_notify_information structure)
struct __attribute__((__packed__)) smb3_notify {
uint32_t completion_filter;
bool watch_tree;
uint32_t data_len;
uint8_t data[];
} __packed;
using CIFS_IOC_NOTIFY_INFO 0xc009cf0b
or equivalently _IOWR(CIFS_IOCTL_MAGIC, 11, struct smb3_notify_info)
The ioctl will block until the server detects a change to that
directory or its subdirectories (if watch_tree is set).
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently much of the smb1 code is built even when
CONFIG_CIFS_ALLOW_INSECURE_LEGACY is disabled.
Move cifssmb.c to only be compiled when insecure legacy is disabled,
and move various SMB1/CIFS helper functions to that ifdef. Some
functions that were not SMB1/CIFS specific needed to be moved out of
cifssmb.c
This shrinks cifs.ko by more than 10% which is good - but also will
help with the eventual movement of the legacy code to a distinct
module. Follow on patches can shrink the number of ifdefs by
code restructuring where smb1 code is wedged in functions that
should be calling dialect specific helper functions instead,
and also by moving some functions from file.c/dir.c/inode.c into
smb1 specific c files.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Correct kernel-doc comments pointed out by the
automated kernel test robot.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
checkpatch complains about source files with filenames (e.g. in
these cases just below the SPDX header in comments at the top of
various files in fs/cifs). It also is helpful to change this now
so will be less confusing when the parent directory is renamed
e.g. from fs/cifs to fs/smb_client (or fs/smbfs)
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add SPDX license identifier and replace license boilerplate.
Corrects various checkpatch errors with the older format for
noting the LGPL license.
Signed-off-by: Steve French <stfrench@microsoft.com>
When mounted multiuser it is hard to dump keys for the other sessions
which makes it hard to debug using network traces (e.g. using wireshark).
Suggested-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Previously we were only able to dump CCM or GCM-128 keys (see "smbinfo keys" e.g.)
to allow network debugging (e.g. wireshark) of mounts to SMB3.1.1 encrypted
shares. But with the addition of GCM-256 support, we have to be able to dump
32 byte instead of 16 byte keys which requires adding an additional ioctl
for that.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Various filesystem support the shutdown ioctl which is used by various
xfstests. The shutdown ioctl sets a flag on the superblock which
prevents open, unlink, symlink, hardlink, rmdir, create etc.
on the file system until unmount and remounted. The two flags supported
in this patch are:
FSOP_GOING_FLAGS_LOGFLUSH and FSOP_GOING_FLAGS_NOLOGFLUSH
which require very little other than blocking new operations (since
we do not cache writes to metadata on the client with cifs.ko).
FSOP_GOING_FLAGS_DEFAULT is not supported yet, but could be added in
the future but would need to call syncfs or equivalent to write out
pending data on the mount.
With this patch various xfstests now work including tests 043 through
046 for example.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
build_path_from_dentry() open-codes dentry_path_raw(). The reason
we can't use dentry_path_raw() in there (and postprocess the
result as needed) is that the callers of build_path_from_dentry()
expect that the object to be freed on cleanup and the string to
be used are at the same address. That's painful, since the path
is naturally built end-to-beginning - we start at the leaf and
go through the ancestors, accumulating the pathname.
Life would be easier if we left the buffer allocation to callers.
It wouldn't be exact-sized buffer, but none of the callers keep
the result for long - it's always freed before the caller returns.
So there's no need to do exact-sized allocation; better use
__getname()/__putname(), same as we do for pathname arguments
of syscalls. What's more, there's no need to do allocation under
spinlocks, so GFP_ATOMIC is not needed.
Next patch will replace the open-coded dentry_path_raw() (in
build_path_from_dentry_optional_prefix()) with calling the real
thing. This patch only introduces wrappers for allocating/freeing
the buffers and switches to new calling conventions:
build_path_from_dentry(dentry, buf)
expects buf to be address of a page-sized object or NULL,
return value is a pathname built inside that buffer on success,
ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if
the pathname won't fit into page. Note that we don't need to
check for failure when allocating the buffer in the caller -
build_path_from_dentry() will do the right thing.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steve French <stfrench@microsoft.com>
Don't leak a reference to tlink during the NOTIFY ioctl
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org> # v5.6+
A commonly used SMB3 feature is change notification, allowing an
app to be notified about changes to a directory. The SMB3
Notify request blocks until the server detects a change to that
directory or its contents that matches the completion flags
that were passed in and the "watch_tree" flag (which indicates
whether subdirectories under this directory should be also
included). See MS-SMB2 2.2.35 for additional detail.
To use this simply pass in the following structure to ioctl:
struct __attribute__((__packed__)) smb3_notify {
uint32_t completion_filter;
bool watch_tree;
} __packed;
using CIFS_IOC_NOTIFY 0x4005cf09
or equivalently _IOW(CIFS_IOCTL_MAGIC, 9, struct smb3_notify)
SMB3 change notification is supported by all major servers.
The ioctl will block until the server detects a change to that
directory or its subdirectories (if watch_tree is set).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag was missing from
some of the operations.
Change all operations to use the macro cifs_create_options() to
set the backup intent flag if needed.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to debug certain problems it is important to be able
to decrypt network traces (e.g. wireshark) but to do this we
need to be able to dump out the encryption/decryption keys.
Dumping them to an ioctl is safer than dumping then to dmesg,
(and better than showing all keys in a pseudofile).
Restrict this to root (CAP_SYS_ADMIN), and only for a mount
that this admin has access to.
Sample smbinfo output:
SMB3.0 encryption
Session Id: 0x82d2ec52
Session Key: a5 6d 81 d0 e c1 ca e1 d8 13 aa 20 e8 f2 cc 71
Server Encryption Key: 1a c3 be ba 3d fc dc 3c e bc 93 9e 50 9e 19 c1
Server Decryption Key: e0 d4 d9 43 1b a2 1b e3 d8 76 77 49 56 f7 20 88
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We do not call cifs_open_file() for directories and thus we do not have a
pSMBFile we can extract the FIDs from.
Solve this by instead always using a compounded open/query/close for
the passthrough ioctl.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This allows userspace tools to query the raw info levels for cifs files
and process the response in userspace.
In particular this is useful for many of those data where there is no
corresponding native data structure in linux.
For example querying the security descriptor for a file and extract the
SIDs.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes gcc '-Wunused-but-set-variable' warning:
fs/cifs/ioctl.c: In function 'cifs_ioctl':
fs/cifs/ioctl.c:164:23: warning:
variable 'cifs_sb' set but not used [-Wunused-but-set-variable]
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Remove the CONFIG_CIFS_SMB2 ifdef and Kconfig option since they
must always be on now.
For various security reasons, SMB3 and later are STRONGLY preferred
over CIFS and older dialects, and SMB3 (and later) will now be
the default dialects so we do not want to allow them to be
ifdeffed out.
In the longer term, we may be able to make older CIFS support
disableable in Kconfig with a new set of #ifdef, but we always
want SMB3 and later support enabled.
Signed-off-by: Steven French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
An open directory may have a NULL private_data pointer prior to readdir.
Fixes: 0de1f4c6f6 ("Add way to query server fs info for smb3")
Cc: stable@vger.kernel.org
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
As with 618763958b, an open directory may have a NULL private_data
pointer prior to readdir. CIFS_ENUMERATE_SNAPSHOTS must check for this
before dereference.
Fixes: 834170c859 ("Enable previous version support")
Signed-off-by: David Disseldorp <ddiss@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
commit 620d8745b3 ("Introduce cifs_copy_file_range()") changes the
behaviour of the cifs ioctl call CIFS_IOC_COPYCHUNK_FILE. In case of
successful writes, it now returns the number of bytes written. This
return value is treated as an error by the xfstest cifs/001. Depending
on the errno set at that time, this may or may not result in the test
failing.
The patch fixes this by setting the return value to 0 in case of
successful writes.
Fixes: commit 620d8745b3 ("Introduce cifs_copy_file_range()")
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <smfrench@gmail.com>
The earlier changes to copy range for cifs unintentionally disabled the more
common form of server side copy.
The patch introduces the file_operations helper cifs_copy_file_range()
which is used by the syscall copy_file_range. The new file operations
helper allows us to perform server side copies for SMB2.0 and 2.1
servers as well as SMB 3.0+ servers which do not support the ioctl
FSCTL_DUPLICATE_EXTENTS_TO_FILE.
The new helper uses the ioctl FSCTL_SRV_COPYCHUNK_WRITE to perform
server side copies. The helper is called by vfs_copy_file_range() only
once an attempt to clone the file using the ioctl
FSCTL_DUPLICATE_EXTENTS_TO_FILE has failed.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Server side copy is one of the most important mechanisms smb2/smb3
supports and it was unintentionally disabled for most use cases.
Renaming calls to reflect the underlying smb2 ioctl called. This is
similar to the name duplicate_extents used for a similar ioctl which is
also used to duplicate files by reusing fs blocks. The name change is to
avoid confusion.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
The btrfs clone ioctls are now adopted by other file systems, with NFS
and CIFS already having support for them, and XFS being under active
development. To avoid growth of various slightly incompatible
implementations, add one to the VFS. Note that clones are different from
file copies in several ways:
- they are atomic vs other writers
- they support whole file clones
- they support 64-bit legth clones
- they do not allow partial success (aka short writes)
- clones are expected to be a fast metadata operation
Because of that it would be rather cumbersome to try to piggyback them on
top of the recent clone_file_range infrastructure. The converse isn't
true and the clone_file_range system call could try clone file range as
a first attempt to copy, something that further patches will enable.
Based on earlier work from Peng Tao.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
FSCTL_SRV_COPYCHUNK_WRITE only requires that the source and target
be on the same server (not the same volume or same share),
so relax the existing check (which required them to be on
the same share). Note that this works to Windows (and presumably
most other NAS) but Samba requires that the source
and target be on the same share. Moving a file across
shares is a common use case and can be very heplful (100x faster).
Signed-off-by: Steve French <steve.french@primarydata.com>
Reviewed-by: David Disseldorp <ddiss@samba.org>
This might lead to local privilege escalation (code execution as
kernel) for systems where the following conditions are met:
- CONFIG_CIFS_SMB2 and CONFIG_CIFS_POSIX are enabled
- a cifs filesystem is mounted where:
- the mount option "vers" was used and set to a value >=2.0
- the attacker has write access to at least one file on the filesystem
To attack this, an attacker would have to guess the target_tcon
pointer (but guessing wrong doesn't cause a crash, it just returns an
error code) and win a narrow race.
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Jann Horn <jann@thejh.net>
Signed-off-by: Steve French <smfrench@gmail.com>
The server exports information about the share and underlying
device under an SMB3 export, including its attributes and
capabilities, which is stored by cifs.ko when first connecting
to the share.
Add ioctl to cifs.ko to allow user space smb3 helper utilities
(in cifs-utils) to display this (e.g. via smb3util).
This information is also useful for debugging and for
resolving configuration errors.
Signed-off-by: Steve French <steve.french@primarydata.com>
set integrity increases reliability of files stored on SMB3 servers.
Add ioctl to allow setting this on files on SMB3 and later mounts.
Signed-off-by: Steve French <steve.french@primarydata.com>
Getting fantastic copy performance with cp --reflink over SMB3.11
using the new FSCTL_DUPLICATE_EXTENTS.
This FSCTL was added in the SMB3.11 dialect (testing was
against REFS file system) so have put it as a 3.11 protocol
specific operation ("vers=3.1.1" on the mount). Tested at
the SMB3 plugfest in Redmond.
It depends on the new FS Attribute (BLOCK_REFCOUNTING) which
is used to advertise support for the ability to do this ioctl
(if you can support multiple files pointing to the same block
than this refcounting ability or equivalent is needed to
support the new reflink-like duplicate extent SMB3 ioctl.
Signed-off-by: Steve French <steve.french@primarydata.com>
It really needs to check that src is non-directory *and* use
{un,}lock_two_nodirectories(). As it is, it's trivial to cause
double-lock (ioctl(fd, CIFS_IOC_COPYCHUNK_FILE, fd)) and if the
last argument is an fd of directory, we are asking for trouble
by violating the locking order - all directories go before all
non-directories. If the last argument is an fd of parent
directory, it has 50% odds of locking child before parent,
which will cause AB-BA deadlock if we race with unlink().
Cc: stable@vger.kernel.org @ 3.13+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Change cifs.ko to using CIFS_IOCTL_COPYCHUNK instead
of BTRFS_IOC_CLONE to avoid confusion about whether
copy-on-write is required or optional for this operation.
SMB2/SMB3 copyoffload had used the BTRFS_IOC_CLONE ioctl since
they both speed up copy by offloading the copy rather than
passing many read and write requests back and forth and both have
identical syntax (passing file handles), but for SMB2/SMB3
CopyChunk the server is not required to use copy-on-write
to make a copy of the file (although some do), and Christoph
has commented that since CopyChunk does not require
copy-on-write we should not reuse BTRFS_IOC_CLONE.
This patch renames the ioctl to use a cifs specific IOCTL
CIFS_IOCTL_COPYCHUNK. This ioctl is particularly important
for SMB2/SMB3 since large file copy over the network otherwise
can be very slow, and with this is often more than 100 times
faster putting less load on server and client.
Note that if a copy syscall is ever introduced, depending on
its requirements/format it could end up using one of the other
three methods that CIFS/SMB2/SMB3 can do for copy offload,
but this method is particularly useful for file copy
and broadly supported (not just by Samba server).
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: David Disseldorp <ddiss@samba.org>
This first patch adds the ability for us to do a server side copy
(ie fast copy offloaded to the server to perform, aka refcopy)
"cp --reflink"
of one file to another located on the same server. This
is much faster than traditional copy (which requires
reading and writing over the network and extra
memcpys).
This first version is not going to be copy
files larger than about 1MB (to Samba) until I add
support for multiple chunks and for autoconfiguring
the chunksize.
It includes:
1) processing of the ioctl
2) marshalling and sending the SMB2/SMB3 fsctl over the network
3) simple parsing of the response
It does not include yet (these will be in followon patches to come soon):
1) support for multiple chunks
2) support for autoconfiguring and remembering the chunksize
3) Support for the older style copychunk which Samba 4.1 server supports
(because this requires write permission on the target file, which
cp does not give you, apparently per-posix). This may require
a distinct tool (other than cp) and other ioctl to implement.
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
Fix unused variable warning when CONFIG_CIFS_POSIX disabled.
fs/cifs/ioctl.c: In function 'cifs_ioctl':
>> fs/cifs/ioctl.c:40:8: warning: unused variable 'ExtAttrMask' [-Wunused-variable]
__u64 ExtAttrMask = 0;
^
Pointed out by 0-DAY kernel build testing backend
Signed-off-by: Steve French <smfrench@gmail.com>
Allow cifs/smb2/smb3 to return whether or not a file is compressed
via lsattr, and allow SMB2/SMB3 to set the per-file compression
flag ("chattr +c filename" on an smb3 mount).
Windows users often set the compressed flag (it can be
done from the desktop and file manager). David Disseldorp
has patches to Samba server to support this (at least on btrfs)
which are complementary to this
Signed-off-by: Steve French <smfrench@gmail.com>
It's not obvious from reading the macro names that these macros
are for debugging. Convert the names to a single more typical
kernel style cifs_dbg macro.
cERROR(1, ...) -> cifs_dbg(VFS, ...)
cFYI(1, ...) -> cifs_dbg(FYI, ...)
cFYI(DBG2, ...) -> cifs_dbg(NOISY, ...)
Move the terminating format newline from the macro to the call site.
Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the
"CIFS VFS: " prefix for VFS messages.
Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y)
$ size fs/cifs/cifs.ko*
text data bss dec hex filename
265245 2525 132 267902 4167e fs/cifs/cifs.ko.new
268359 2525 132 271016 422a8 fs/cifs/cifs.ko.old
Other miscellaneous changes around these conversions:
o Miscellaneous typo fixes
o Add terminating \n's to almost all formats and remove them
from the macros to be more kernel style like. A few formats
previously had defective \n's
o Remove unnecessary OOM messages as kmalloc() calls dump_stack
o Coalesce formats to make grep easier,
added missing spaces when coalescing formats
o Use %s, __func__ instead of embedded function name
o Removed unnecessary "cifs: " prefixes
o Convert kzalloc with multiply to kcalloc
o Remove unused cifswarn macro
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This is help us to extend the code for future protocols that can use
another fid mechanism (as SMB2 that has it divided into two parts:
persistent and violatile).
Also rename variables and refactor the code around the changes.
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
This was used by an ancient version of umount.cifs and in nowhere else
that I'm aware of. Let's add a warning now and dump it for 3.7.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Commit 13cfb7334e made cifs_ioctl use the tlink attached to the
cifsFileInfo for a filp. This ignores the case of an open directory
however, which in CIFS can have a NULL private_data until a readdir
is done on it.
This patch re-adds the NULL pointer checks that were removed in commit
50ae28f01 and moves the setting of tcon and "caps" variables lower.
Long term, a better fix would be to establish a f_op->open routine for
directories that populates that field at open time, but that requires
some other changes to how readdir calls are handled.
Reported-by: Kjell Rune Skaaraas <kjella79@yahoo.no>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Stanse found that pSMBFile in cifs_ioctl and file->f_path.dentry in
cifs_user_write are dereferenced prior their test to NULL.
The alternative is not to dereference them before the tests. The patch is
to point out the problem, you have to decide.
While at it we cache the inode in cifs_user_write to a local variable
and use all over the function.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
cifsFileInfo needs a pointer to a tcon, but it doesn't currently hold a
reference to it. Change it to keep a pointer to a tcon_link instead and
hold a reference to it.
That will keep the tcon from being freed until the file is closed.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Steve French