Commit Graph

989 Commits

Author SHA1 Message Date
Linus Torvalds
1a33418a69 Merge tag '6.15-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:

 - Fix dentry leak which can cause umount crash

 - Add warning for parse contexts error on compounded operation

* tag '6.15-rc5-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: Avoid race in open_cached_dir with lease breaks
  smb3 client: warn when parse contexts returns error on compounded operation
2025-05-09 16:45:21 -07:00
Linus Torvalds
80ae5fb229 Merge tag 'v6.15-rc5-ksmbd-server-fixes' of git://git.samba.org/ksmbd
Pull smb server fixes from Steve French:

 - Fix UAF closing file table (e.g. in tree disconnect)

 - Fix potential out of bounds write

 - Fix potential memory leak parsing lease state in open

 - Fix oops in rename with empty target

* tag 'v6.15-rc5-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
  ksmbd: Fix UAF in __close_file_table_ids
  ksmbd: prevent out-of-bounds stream writes by validating *pos
  ksmbd: fix memory leak in parse_lease_state()
  ksmbd: prevent rename with empty string
2025-05-08 08:22:35 -07:00
Paul Aurich
3ca02e63ed smb: client: Avoid race in open_cached_dir with lease breaks
A pre-existing valid cfid returned from find_or_create_cached_dir might
race with a lease break, meaning open_cached_dir doesn't consider it
valid, and thinks it's newly-constructed. This leaks a dentry reference
if the allocation occurs before the queued lease break work runs.

Avoid the race by extending holding the cfid_list_lock across
find_or_create_cached_dir and when the result is checked.

Cc: stable@vger.kernel.org
Reviewed-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Paul Aurich <paul@darkrain42.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-07 15:24:46 -05:00
Steve French
d90b023718 smb3 client: warn when parse contexts returns error on compounded operation
Coverity noticed that the rc on smb2_parse_contexts() was not being checked
in the case of compounded operations.  Since we don't want to stop parsing
the following compounded responses which are likely valid, we can't easily
error out here, but at least print a warning message if server has a bug
causing us to skip parsing the open response contexts.

Addresses-Coverity: 1639191
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-06 09:05:15 -05:00
Sean Heelan
36991c1ccd ksmbd: Fix UAF in __close_file_table_ids
A use-after-free is possible if one thread destroys the file
via __ksmbd_close_fd while another thread holds a reference to
it. The existing checks on fp->refcount are not sufficient to
prevent this.

The fix takes ft->lock around the section which removes the
file from the file table. This prevents two threads acquiring the
same file pointer via __close_file_table_ids, as well as the other
functions which retrieve a file from the IDR and which already use
this same lock.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Heelan <seanheelan@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-06 08:37:02 -05:00
Norbert Szetei
0ca6df4f40 ksmbd: prevent out-of-bounds stream writes by validating *pos
ksmbd_vfs_stream_write() did not validate whether the write offset
(*pos) was within the bounds of the existing stream data length (v_len).
If *pos was greater than or equal to v_len, this could lead to an
out-of-bounds memory write.

This patch adds a check to ensure *pos is less than v_len before
proceeding. If the condition fails, -EINVAL is returned.

Cc: stable@vger.kernel.org
Signed-off-by: Norbert Szetei <norbert@doyensec.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-06 08:36:36 -05:00
Linus Torvalds
daad00c063 Merge tag '6.15-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:

 - fix posix mkdir error to ksmbd (also avoids crash in
   cifs_destroy_request_bufs)

 - two smb1 fixes: fixing querypath info and setpathinfo to old servers

 - fix rsize/wsize when not multiple of page size to address DIO
   reads/writes

* tag '6.15-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: ensure aligned IO sizes
  cifs: Fix changing times and read-only attr over SMB1 smb_set_file_info() function
  cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()
  smb: client: fix zero length for mkdir POSIX create context
2025-05-02 14:37:16 -07:00
Wang Zhaolong
eb4447bcce ksmbd: fix memory leak in parse_lease_state()
The previous patch that added bounds check for create lease context
introduced a memory leak. When the bounds check fails, the function
returns NULL without freeing the previously allocated lease_ctx_info
structure.

This patch fixes the issue by adding kfree(lreq) before returning NULL
in both boundary check cases.

Fixes: bab703ed84 ("ksmbd: add bounds check for create lease context")
Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-01 18:58:48 -05:00
Namjae Jeon
53e3e5babc ksmbd: prevent rename with empty string
Client can send empty newname string to ksmbd server.
It will cause a kernel oops from d_alloc.
This patch return the error when attempting to rename
a file or directory with an empty new name string.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-01 18:58:48 -05:00
Paulo Alcantara
c59f7c9661 smb: client: ensure aligned IO sizes
Make all IO sizes multiple of PAGE_SIZE, either negotiated by the
server or passed through rsize, wsize and bsize mount options, to
prevent from breaking DIO reads and writes against servers that
enforce alignment as specified in MS-FSA 2.1.5.3 and 2.1.5.4.

Cc: linux-cifs@vger.kernel.org
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-05-01 08:35:58 -05:00
Pali Rohár
f122121796 cifs: Fix changing times and read-only attr over SMB1 smb_set_file_info() function
Function CIFSSMBSetPathInfo() is not supported by non-NT servers and
returns error. Fallback code via open filehandle and CIFSSMBSetFileInfo()
does not work neither because CIFS_open() works also only on NT server.

Therefore currently the whole smb_set_file_info() function as a SMB1
callback for the ->set_file_info() does not work with older non-NT SMB
servers, like Win9x and others.

This change implements fallback code in smb_set_file_info() which will
works with any server and allows to change time values and also to set or
clear read-only attributes.

To make existing fallback code via CIFSSMBSetFileInfo() working with also
non-NT servers, it is needed to change open function from CIFS_open()
(which is NT specific) to cifs_open_file() which works with any server
(this is just a open wrapper function which choose the correct open
function supported by the server).

CIFSSMBSetFileInfo() is working also on non-NT servers, but zero time
values are not treated specially. So first it is needed to fill all time
values if some of them are missing, via cifs_query_path_info() call.

There is another issue, opening file in write-mode (needed for changing
attributes) is not possible when the file has read-only attribute set.
The only option how to clear read-only attribute is via SMB_COM_SETATTR
command. And opening directory is not possible neither and here the
SMB_COM_SETATTR command is the only option how to change attributes.
And CIFSSMBSetFileInfo() does not honor setting read-only attribute, so
for setting is also needed to use SMB_COM_SETATTR command.

Existing code in cifs_query_path_info() is already using SMB_COM_GETATTR as
a fallback code path (function SMBQueryInformation()), so introduce a new
function SMBSetInformation which will implement SMB_COM_SETATTR command.

My testing showed that Windows XP SMB1 client is also using SMB_COM_SETATTR
command for setting or clearing read-only attribute against non-NT server.
So this can prove that this is the correct way how to do it.

With this change it is possible set all 4 time values and all attributes,
including clearing and setting read-only bit on non-NT SMB servers.
Tested against Win98 SMB1 server.

This change fixes "touch" command which was failing when called on existing
file. And fixes also "chmod +w" and "chmod -w" commands which were also
failing (as they are changing read-only attribute).

Note that this change depends on following change
"cifs: Improve cifs_query_path_info() and cifs_query_file_info()"
as it require to query all 4 time attribute values.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30 09:48:39 -05:00
Pali Rohár
1041c117a2 cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()
When CAP_NT_SMBS was not negotiated then do not issue CIFSSMBQPathInfo()
and CIFSSMBQFileInfo() commands. CIFSSMBQPathInfo() is not supported by
non-NT Win9x SMB server and CIFSSMBQFileInfo() returns from Win9x SMB
server bogus data in Attributes field (for example lot of files are marked
as reparse points, even Win9x does not support them and read-only bit is
not marked for read-only files). Correct information is returned by
CIFSFindFirst() or SMBQueryInformation() command.

So as a fallback in cifs_query_path_info() function use CIFSFindFirst()
with SMB_FIND_FILE_FULL_DIRECTORY_INFO level which is supported by both NT
and non-NT servers and as a last option use SMBQueryInformation() as it was
before.

And in function cifs_query_file_info() immediately returns -EOPNOTSUPP when
not communicating with NT server. Client then revalidate inode entry by the
cifs_query_path_info() call, which is working fine. So fstat() syscall on
already opened file will receive correct information.

Note that both fallback functions in non-UNICODE mode expands wildcards.
Therefore those fallback functions cannot be used on paths which contain
SMB wildcard characters (* ? " > <).

CIFSFindFirst() returns all 4 time attributes as opposite of
SMBQueryInformation() which returns only one.

With this change it is possible to query all 4 times attributes from Win9x
server and at the same time, client minimize sending of unsupported
commands to server.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30 09:48:39 -05:00
Jethro Donaldson
74c72419ec smb: client: fix zero length for mkdir POSIX create context
SMB create requests issued via smb311_posix_mkdir() have an incorrect
length of zero bytes for the POSIX create context data. ksmbd server
rejects such requests and logs "cli req too short" causing mkdir to fail
with "invalid argument" on the client side.  It also causes subsequent
rmmod to crash in cifs_destroy_request_bufs()

Inspection of packets sent by cifs.ko using wireshark show valid data for
the SMB2_POSIX_CREATE_CONTEXT is appended with the correct offset, but
with an incorrect length of zero bytes. Fails with ksmbd+cifs.ko only as
Windows server/client does not use POSIX extensions.

Fix smb311_posix_mkdir() to set req->CreateContextsLength as part of
appending the POSIX creation context to the request.

Signed-off-by: Jethro Donaldson <devel@jro.nz>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-30 09:48:27 -05:00
Sean Heelan
2fc9feff45 ksmbd: fix use-after-free in session logoff
The sess->user object can currently be in use by another thread, for
example if another connection has sent a session setup request to
bind to the session being free'd. The handler for that connection could
be in the smb2_sess_setup function which makes use of sess->user.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Heelan <seanheelan@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-25 18:22:26 -05:00
Sean Heelan
e86e9134e1 ksmbd: fix use-after-free in kerberos authentication
Setting sess->user = NULL was introduced to fix the dangling pointer
created by ksmbd_free_user. However, it is possible another thread could
be operating on the session and make use of sess->user after it has been
passed to ksmbd_free_user but before sess->user is set to NULL.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Heelan <seanheelan@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-25 18:22:01 -05:00
Namjae Jeon
a1f46c99d9 ksmbd: fix use-after-free in ksmbd_session_rpc_open
A UAF issue can occur due to a race condition between
ksmbd_session_rpc_open() and __session_rpc_close().
Add rpc_lock to the session to protect it.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-22 20:45:43 -05:00
Salah Triki
af5226abb4 smb: server: smb2pdu: check return value of xa_store()
xa_store() may fail so check its return value and return error code if
error occurred.

Signed-off-by: Salah Triki <salah.triki@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-22 20:45:43 -05:00
Linus Torvalds
8560697b23 Merge tag '6.15-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:

 - Fix hard link lease key problem when close is deferred

 - Revert the socket lockdep/refcount workarounds done in cifs.ko now
   that it is fixed at the socket layer

* tag '6.15-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  Revert "smb: client: fix TCP timers deadlock after rmmod"
  Revert "smb: client: Fix netns refcount imbalance causing leaks and use-after-free"
  smb3 client: fix open hardlink on deferred close file error
2025-04-18 20:10:42 -07:00
Denis Arefev
a93ff74282 ksmbd: Prevent integer overflow in calculation of deadtime
The user can set any value for 'deadtime'. This affects the arithmetic
expression 'req->deadtime * SMB_ECHO_INTERVAL', which is subject to
overflow. The added check makes the server behavior more predictable.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 0626e6641f ("cifsd: add server handler for central processing and tranport layers")
Cc: stable@vger.kernel.org
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Namjae Jeon
b37f2f332b ksmbd: fix the warning from __kernel_write_iter
[ 2110.972290] ------------[ cut here ]------------
[ 2110.972301] WARNING: CPU: 3 PID: 735 at fs/read_write.c:599 __kernel_write_iter+0x21b/0x280

This patch doesn't allow writing to directory.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Namjae Jeon
18b4fac5ef ksmbd: fix use-after-free in smb_break_all_levII_oplock()
There is a room in smb_break_all_levII_oplock that can cause racy issues
when unlocking in the middle of the loop. This patch use read lock
to protect whole loop.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Namjae Jeon
21a4e47578 ksmbd: fix use-after-free in __smb2_lease_break_noti()
Move tcp_transport free to ksmbd_conn_free. If ksmbd connection is
referenced when ksmbd server thread terminates, It will not be freed,
but conn->tcp_transport is freed. __smb2_lease_break_noti can be performed
asynchronously when the connection is disconnected. __smb2_lease_break_noti
calls ksmbd_conn_write, which can cause use-after-free
when conn->ksmbd_transport is already freed.

Cc: stable@vger.kernel.org
Reported-by: Norbert Szetei <norbert@doyensec.com>
Tested-by: Norbert Szetei <norbert@doyensec.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Namjae Jeon
1df0d4c616 ksmbd: fix WARNING "do not call blocking ops when !TASK_RUNNING"
wait_event_timeout() will set the state of the current
task to TASK_UNINTERRUPTIBLE, before doing the condition check. This
means that ksmbd_durable_scavenger_alive() will try to acquire the mutex
while already in a sleeping state. The scheduler warns us by giving
the following warning:

do not call blocking ops when !TASK_RUNNING; state=2 set at
 [<0000000061515a6f>] prepare_to_wait_event+0x9f/0x6c0
WARNING: CPU: 2 PID: 4147 at kernel/sched/core.c:10099 __might_sleep+0x12f/0x160

mutex lock is not needed in ksmbd_durable_scavenger_alive().

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Sean Heelan
1e440d5b25 ksmbd: Fix dangling pointer in krb_authenticate
krb_authenticate frees sess->user and does not set the pointer
to NULL. It calls ksmbd_krb5_authenticate to reinitialise
sess->user but that function may return without doing so. If
that happens then smb2_sess_setup, which calls krb_authenticate,
will be accessing free'd memory when it later uses sess->user.

Cc: stable@vger.kernel.org
Signed-off-by: Sean Heelan <seanheelan@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-14 22:21:26 -05:00
Kuniyuki Iwashima
95d2b9f693 Revert "smb: client: fix TCP timers deadlock after rmmod"
This reverts commit e9f2517a3e.

Commit e9f2517a3e ("smb: client: fix TCP timers deadlock after
rmmod") is intended to fix a null-ptr-deref in LOCKDEP, which is
mentioned as CVE-2024-54680, but is actually did not fix anything;
The issue can be reproduced on top of it. [0]

Also, it reverted the change by commit ef7134c7fc ("smb: client:
Fix use-after-free of network namespace.") and introduced a real
issue by reviving the kernel TCP socket.

When a reconnect happens for a CIFS connection, the socket state
transitions to FIN_WAIT_1.  Then, inet_csk_clear_xmit_timers_sync()
in tcp_close() stops all timers for the socket.

If an incoming FIN packet is lost, the socket will stay at FIN_WAIT_1
forever, and such sockets could be leaked up to net.ipv4.tcp_max_orphans.

Usually, FIN can be retransmitted by the peer, but if the peer aborts
the connection, the issue comes into reality.

I warned about this privately by pointing out the exact report [1],
but the bogus fix was finally merged.

So, we should not stop the timers to finally kill the connection on
our side in that case, meaning we must not use a kernel socket for
TCP whose sk->sk_net_refcnt is 0.

The kernel socket does not have a reference to its netns to make it
possible to tear down netns without cleaning up every resource in it.

For example, tunnel devices use a UDP socket internally, but we can
destroy netns without removing such devices and let it complete
during exit.  Otherwise, netns would be leaked when the last application
died.

However, this is problematic for TCP sockets because TCP has timers to
close the connection gracefully even after the socket is close()d.  The
lifetime of the socket and its netns is different from the lifetime of
the underlying connection.

If the socket user does not maintain the netns lifetime, the timer could
be fired after the socket is close()d and its netns is freed up, resulting
in use-after-free.

Actually, we have seen so many similar issues and converted such sockets
to have a reference to netns.

That's why I converted the CIFS client socket to have a reference to
netns (sk->sk_net_refcnt == 1), which is somehow mentioned as out-of-scope
of CIFS and technically wrong in e9f2517a3e, but **is in-scope and right
fix**.

Regarding the LOCKDEP issue, we can prevent the module unload by
bumping the module refcount when switching the LOCKDDEP key in
sock_lock_init_class_and_name(). [2]

For a while, let's revert the bogus fix.

Note that now we can use sk_net_refcnt_upgrade() for the socket
conversion, but I'll do so later separately to make backport easy.

Link: https://lore.kernel.org/all/20250402020807.28583-1-kuniyu@amazon.com/ #[0]
Link: https://lore.kernel.org/netdev/c08bd5378da647a2a4c16698125d180a@huawei.com/ #[1]
Link: https://lore.kernel.org/lkml/20250402005841.19846-1-kuniyu@amazon.com/ #[2]
Fixes: e9f2517a3e ("smb: client: fix TCP timers deadlock after rmmod")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13 17:24:55 -05:00
Kuniyuki Iwashima
c707193a17 Revert "smb: client: Fix netns refcount imbalance causing leaks and use-after-free"
This reverts commit 4e7f1644f2.

The commit e9f2517a3e ("smb: client: fix TCP timers deadlock after
rmmod") is not only a bogus fix for LOCKDEP null-ptr-deref but also
introduces a real issue, TCP sockets leak, which will be explained in
detail in the next revert.

Also, CNA assigned CVE-2024-54680 to it but is rejecting it. [0]

Thus, we are reverting the commit and its follow-up commit 4e7f1644f2
("smb: client: Fix netns refcount imbalance causing leaks and
use-after-free").

Link: https://lore.kernel.org/all/2025040248-tummy-smilingly-4240@gregkh/ #[0]
Fixes: 4e7f1644f2 ("smb: client: Fix netns refcount imbalance causing leaks and use-after-free")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13 17:24:55 -05:00
Chunjie Zhu
262b73ef44 smb3 client: fix open hardlink on deferred close file error
The following Python script results in unexpected behaviour when run on
a CIFS filesystem against a Windows Server:

    # Create file
    fd = os.open('test', os.O_WRONLY|os.O_CREAT)
    os.write(fd, b'foo')
    os.close(fd)

    # Open and close the file to leave a pending deferred close
    fd = os.open('test', os.O_RDONLY|os.O_DIRECT)
    os.close(fd)

    # Try to open the file via a hard link
    os.link('test', 'new')
    newfd = os.open('new', os.O_RDONLY|os.O_DIRECT)

The final open returns EINVAL due to the server returning
STATUS_INVALID_PARAMETER. The root cause of this is that the client
caches lease keys per inode, but the spec requires them to be related to
the filename which causes problems when hard links are involved:

From MS-SMB2 section 3.3.5.9.11:

"The server MUST attempt to locate a Lease by performing a lookup in the
LeaseTable.LeaseList using the LeaseKey in the
SMB2_CREATE_REQUEST_LEASE_V2 as the lookup key. If a lease is found,
Lease.FileDeleteOnClose is FALSE, and Lease.Filename does not match the
file name for the incoming request, the request MUST be failed with
STATUS_INVALID_PARAMETER"

On client side, we first check the context of file open, if it hits above
conditions, we first close all opening files which are belong to the same
inode, then we do open the hard link file.

Cc: stable@vger.kernel.org
Signed-off-by: Chunjie Zhu <chunjie.zhu@cloud.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-13 17:24:55 -05:00
Steve French
56c283b9e0 smb3: Add defines for two new FileSystemAttributes
Two new file system attributes were recently added. See MS-FSCC 2.5.1:
       FILE_SUPPORTS_POSIX_UNLINK_RENAME and
       FILE_RETURNS_CLEANUP_RESULT_INFO

Update the missing defines for ksmbd and cifs.ko

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 23:42:16 -05:00
Pali Rohár
ef86ab131d cifs: Fix querying of WSL CHR and BLK reparse points over SMB1
When reparse point in SMB1 query_path_info() callback was detected then
query also for EA $LXDEV. In this EA are stored device major and minor
numbers used by WSL CHR and BLK reparse points. Without major and minor
numbers, stat() syscall does not work for char and block devices.

Similar code is already in SMB2+ query_path_info() callback function.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 15:49:19 -05:00
Pali Rohár
56c0bea52c cifs: Split parse_reparse_point callback to functions: get buffer and parse buffer
Parsing reparse point buffer is generic for all SMB versions and is already
implemented by global function parse_reparse_point().

Getting reparse point buffer from the SMB response is SMB version specific,
so introduce for it a new callback get_reparse_point_buffer.

This functionality split is needed for followup change - getting reparse
point buffer without parsing it.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 15:37:35 -05:00
Pali Rohár
12193b9801 cifs: Improve handling of name surrogate reparse points in reparse.c
Like previous changes for file inode.c, handle directory name surrogate
reparse points generally also in reparse.c.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 15:37:26 -05:00
Pali Rohár
9ce7351291 cifs: Remove explicit handling of IO_REPARSE_TAG_MOUNT_POINT in inode.c
IO_REPARSE_TAG_MOUNT_POINT is just a specific case of directory Name
Surrogate reparse point. As reparse_info_to_fattr() already handles all
directory Name Surrogate reparse point (done by the previous change),
there is no need to have explicit case for IO_REPARSE_TAG_MOUNT_POINT.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 15:37:20 -05:00
Pali Rohár
16cb6b0509 cifs: Fix encoding of SMB1 Session Setup Kerberos Request in non-UNICODE mode
Like in UNICODE mode, SMB1 Session Setup Kerberos Request contains oslm and
domain strings.

Extract common code into ascii_oslm_strings() and ascii_domain_string()
functions (similar to unicode variants) and use these functions in
non-UNICODE code path in sess_auth_kerberos().

Decision if non-UNICODE or UNICODE mode is used is based on the
SMBFLG2_UNICODE flag in Flags2 packed field, and not based on the
capabilities of server. Fix this check too.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 13:34:32 -05:00
Paulo Alcantara
9502dd5c70 smb: client: fix UAF in decryption with multichannel
After commit f7025d8616 ("smb: client: allocate crypto only for
primary server") and commit b0abcd65ec ("smb: client: fix UAF in
async decryption"), the channels started reusing AEAD TFM from primary
channel to perform synchronous decryption, but that can't done as
there could be multiple cifsd threads (one per channel) simultaneously
accessing it to perform decryption.

This fixes the following KASAN splat when running fstest generic/249
with 'vers=3.1.1,multichannel,max_channels=4,seal' against Windows
Server 2022:

BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xba/0x110
Read of size 8 at addr ffff8881046c18a0 by task cifsd/986
CPU: 3 UID: 0 PID: 986 Comm: cifsd Not tainted 6.15.0-rc1 #1
PREEMPT(voluntary)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41
04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x5d/0x80
 print_report+0x156/0x528
 ? gf128mul_4k_lle+0xba/0x110
 ? __virt_addr_valid+0x145/0x300
 ? __phys_addr+0x46/0x90
 ? gf128mul_4k_lle+0xba/0x110
 kasan_report+0xdf/0x1a0
 ? gf128mul_4k_lle+0xba/0x110
 gf128mul_4k_lle+0xba/0x110
 ghash_update+0x189/0x210
 shash_ahash_update+0x295/0x370
 ? __pfx_shash_ahash_update+0x10/0x10
 ? __pfx_shash_ahash_update+0x10/0x10
 ? __pfx_extract_iter_to_sg+0x10/0x10
 ? ___kmalloc_large_node+0x10e/0x180
 ? __asan_memset+0x23/0x50
 crypto_ahash_update+0x3c/0xc0
 gcm_hash_assoc_remain_continue+0x93/0xc0
 crypt_message+0xe09/0xec0 [cifs]
 ? __pfx_crypt_message+0x10/0x10 [cifs]
 ? _raw_spin_unlock+0x23/0x40
 ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs]
 decrypt_raw_data+0x229/0x380 [cifs]
 ? __pfx_decrypt_raw_data+0x10/0x10 [cifs]
 ? __pfx_cifs_read_iter_from_socket+0x10/0x10 [cifs]
 smb3_receive_transform+0x837/0xc80 [cifs]
 ? __pfx_smb3_receive_transform+0x10/0x10 [cifs]
 ? __pfx___might_resched+0x10/0x10
 ? __pfx_smb3_is_transform_hdr+0x10/0x10 [cifs]
 cifs_demultiplex_thread+0x692/0x1570 [cifs]
 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
 ? rcu_is_watching+0x20/0x50
 ? rcu_lockdep_current_cpu_online+0x62/0xb0
 ? find_held_lock+0x32/0x90
 ? kvm_sched_clock_read+0x11/0x20
 ? local_clock_noinstr+0xd/0xd0
 ? trace_irq_enable.constprop.0+0xa8/0xe0
 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
 kthread+0x1fe/0x380
 ? kthread+0x10f/0x380
 ? __pfx_kthread+0x10/0x10
 ? local_clock_noinstr+0xd/0xd0
 ? ret_from_fork+0x1b/0x60
 ? local_clock+0x15/0x30
 ? lock_release+0x29b/0x390
 ? rcu_is_watching+0x20/0x50
 ? __pfx_kthread+0x10/0x10
 ret_from_fork+0x31/0x60
 ? __pfx_kthread+0x10/0x10
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Tested-by: David Howells <dhowells@redhat.com>
Reported-by: Steve French <stfrench@microsoft.com>
Closes: https://lore.kernel.org/r/CAH2r5mu6Yc0-RJXM3kFyBYUB09XmXBrNodOiCVR4EDrmxq5Szg@mail.gmail.com
Fixes: f7025d8616 ("smb: client: allocate crypto only for primary server")
Fixes: b0abcd65ec ("smb: client: fix UAF in async decryption")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-09 10:24:55 -05:00
Pali Rohár
c7efac7f1c cifs: Fix support for WSL-style symlinks
MS-FSCC in section 2.1.2.7 LX SYMLINK REPARSE_DATA_BUFFER now contains
documentation about WSL symlink reparse point buffers.

https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/68337353-9153-4ee1-ac6b-419839c3b7ad

Fix the struct reparse_wsl_symlink_data_buffer to reflect buffer fields
according to the MS-FSCC documentation.

Fix the Linux SMB client to correctly fill the WSL symlink reparse point
buffer when creaing new WSL-style symlink. There was a mistake during
filling the data part of the reparse point buffer. It should starts with
bytes "\x02\x00\x00\x00" (which represents version 2) but this constant was
written as number 0x02000000 encoded in little endian, which resulted bytes
"\x00\x00\x00\x02". This change is fixing this mistake.

Fixes: 4e2043be5c ("cifs: Add support for creating WSL-style symlinks")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-08 18:38:03 -05:00
Steve French
b365b9d404 smb311 client: fix missing tcon check when mounting with linux/posix extensions
When mounting the same share twice, once with the "linux" mount parameter
(or equivalently "posix") and then once without (or e.g. with "nolinux"),
we were incorrectly reusing the same tree connection for both mounts.
This meant that the first mount of the share on the client, would
cause subsequent mounts of that same share on the same client to
ignore that mount parm ("linux" vs. "nolinux") and incorrectly reuse
the same tcon.

Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-07 01:08:07 -05:00
Pali Rohár
6f8a394aa9 cifs: Ensure that all non-client-specific reparse points are processed by the server
Fix regression in mounts to e.g. onedrive shares.

Generally, reparse points are processed by the SMB server during the
SMB OPEN request, but there are few reparse points which do not have
OPEN-like meaning for the SMB server and has to be processed by the SMB
client. Those are symlinks and special files (fifo, socket, block, char).

For Linux SMB client, it is required to process also name surrogate reparse
points as they represent another entity on the SMB server system. Linux
client will mark them as separate mount points. Examples of name surrogate
reparse points are NTFS junction points (e.g. created by the "mklink" tool
on Windows servers).

So after processing the name surrogate reparse points, clear the
-EOPNOTSUPP error code returned from the parse_reparse_point() to let SMB
server to process reparse points.

And remove printing misleading error message "unhandled reparse tag:" as
reparse points are handled by SMB server and hence unhandled fact is normal
operation.

Fixes: cad3fc0a4c ("cifs: Throw -EOPNOTSUPP error on unsupported reparse point type from parse_reparse_point()")
Fixes: b587fd1286 ("cifs: Treat unhandled directory name surrogate reparse points as mount directory nodes")
Cc: stable@vger.kernel.org
Reported-by: Junwen Sun <sunjw8888@gmail.com>
Tested-by: Junwen Sun <sunjw8888@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-07 01:07:22 -05:00
Linus Torvalds
9f867ba24d Merge tag '6.15-rc-part2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull more smb client updates from Steve French:

 - reconnect fixes: three for updating rsize/wsize and an SMB1 reconnect
   fix

 - RFC1001 fixes: fixing connections to nonstandard ports, and negprot
   retries

 - fix mfsymlinks to old servers

 - make mapping of open flags for SMB1 more accurate

 - permission fixes: adding retry on open for write, and one for stat to
   workaround unexpected access denied

 - add two new xattrs, one for retrieving SACL and one for retrieving
   owner (without having to retrieve the whole ACL)

 - fix mount parm validation for echo_interval

 - minor cleanup (including removing now unneeded cifs_truncate_page)

* tag '6.15-rc-part2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal version number
  cifs: Implement is_network_name_deleted for SMB1
  cifs: Remove cifs_truncate_page() as it should be superfluous
  cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL
  cifs: Improve SMB2+ stat() to work also without FILE_READ_ATTRIBUTES
  cifs: Add fallback for SMB2 CREATE without FILE_READ_ATTRIBUTES
  cifs: Fix querying and creating MF symlinks over SMB1
  cifs: Fix access_flags_to_smbopen_mode
  cifs: Fix negotiate retry functionality
  cifs: Improve handling of NetBIOS packets
  cifs: Allow to disable or force initialization of NetBIOS session
  cifs: Add a new xattr system.smb3_ntsd_owner for getting or setting owner
  cifs: Add a new xattr system.smb3_ntsd_sacl for getting or setting SACLs
  smb: client: Update IO sizes after reconnection
  smb: client: Store original IO parameters and prevent zero IO sizes
  smb:client: smb: client: Add reverse mapping from tcon to superblocks
  cifs: remove unreachable code in cifs_get_tcp_session()
  cifs: fix integer overflow in match_server()
2025-04-04 15:27:43 -07:00
Steve French
827a1bd9af cifs: update internal version number
To 2.52

Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-02 20:01:14 -05:00
Pali Rohár
28753e4304 cifs: Implement is_network_name_deleted for SMB1
This change allows Linux SMB1 client to autoreconnect the share when it is
modified on server by admin operation which removes and re-adds it.

Implementation is reused from SMB2+ is_network_name_deleted callback. There
are just adjusted checks for error codes and access to struct smb_hdr.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-02 20:01:14 -05:00
David Howells
f83e10a233 cifs: Remove cifs_truncate_page() as it should be superfluous
The calls to cifs_truncate_page() should be superfluous as the places that
call it also call truncate_setsize() or cifs_setsize() and therefore
truncate_pagecache() which should also clear the tail part of the folio
containing the EOF marker.

Further, smb3_simple_falloc() calls both cifs_setsize() and
truncate_setsize() in addition to cifs_truncate_page().

Remove the superfluous calls.

This gets rid of another function referring to struct page.

[Should cifs_setsize() also set inode->i_blocks?]

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Matthew Wilcox <willy@infradead.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>
2025-04-02 20:00:39 -05:00
Namjae Jeon
c8b5b7c5da ksmbd: fix null pointer dereference in alloc_preauth_hash()
The Client send malformed smb2 negotiate request. ksmbd return error
response. Subsequently, the client can send smb2 session setup even
thought conn->preauth_info is not allocated.
This patch add KSMBD_SESS_NEED_SETUP status of connection to ignore
session setup request if smb2 negotiate phase is not complete.

Cc: stable@vger.kernel.org
Tested-by: Steve French <stfrench@microsoft.com>
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-26505
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 23:02:20 -05:00
Pali Rohár
e97aec7889 cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL
Individual bits GENERIC_READ, GENERIC_EXECUTE and GENERIC_ALL have meaning
which includes also access right for FILE_READ_ATTRIBUTES. So specifying
FILE_READ_ATTRIBUTES bit together with one of those GENERIC (except
GENERIC_WRITE) does not do anything.

This change prevents calling additional (fallback) code and sending more
requests without FILE_READ_ATTRIBUTES when the primary request fails on
-EACCES, as it is not needed at all.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 04:58:09 -05:00
Pali Rohár
b07687edee cifs: Improve SMB2+ stat() to work also without FILE_READ_ATTRIBUTES
If SMB2_OP_QUERY_INFO (called when POSIX extensions are not used) failed
with STATUS_ACCESS_DENIED then it means that caller does not have
permission to open the path with FILE_READ_ATTRIBUTES access and therefore
cannot issue SMB2_OP_QUERY_INFO command.

This will result in the -EACCES error from stat() sycall.

There is an alternative way how to query limited information about path but
still suitable for stat() syscall. SMB2 OPEN/CREATE operation returns in
its successful response subset of query information.

So try to open the path without FILE_READ_ATTRIBUTES but with
MAXIMUM_ALLOWED access which will grant the maximum possible access to the
file and the response will contain required query information for stat()
syscall.

This will improve smb2_query_path_info() to query also files which do not
grant FILE_READ_ATTRIBUTES access to caller.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 04:58:05 -05:00
Pali Rohár
e255612b5e cifs: Add fallback for SMB2 CREATE without FILE_READ_ATTRIBUTES
Some operations, like WRITE, does not require FILE_READ_ATTRIBUTES access.

So when FILE_READ_ATTRIBUTES is not explicitly requested for
smb2_open_file() then first try to do SMB2 CREATE with FILE_READ_ATTRIBUTES
access (like it was before) and then fallback to SMB2 CREATE without
FILE_READ_ATTRIBUTES access (less common case).

This change allows to complete WRITE operation to a file when it does not
grant FILE_READ_ATTRIBUTES permission and its parent directory does not
grant READ_DATA permission (parent directory READ_DATA is implicit grant of
child FILE_READ_ATTRIBUTES permission).

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 04:58:00 -05:00
Pali Rohár
4236ac9fe5 cifs: Fix querying and creating MF symlinks over SMB1
Old SMB1 servers without CAP_NT_SMBS do not support CIFS_open() function
and instead SMBLegacyOpen() needs to be used. This logic is already handled
in cifs_open_file() function, which is server->ops->open callback function.

So for querying and creating MF symlinks use open callback function instead
of CIFS_open() function directly.

This change fixes querying and creating new MF symlinks on Windows 98.
Currently cifs_query_mf_symlink() is not able to detect MF symlink and
cifs_create_mf_symlink() is failing with EIO error.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 01:54:17 -05:00
Pali Rohár
6aa9f1c9cd cifs: Fix access_flags_to_smbopen_mode
When converting access_flags to SMBOPEN mode, check for all possible access
flags, not only GENERIC_READ and GENERIC_WRITE flags.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 01:54:17 -05:00
Pali Rohár
e94e882a6d cifs: Fix negotiate retry functionality
SMB negotiate retry functionality in cifs_negotiate() is currently broken
and does not work when doing socket reconnect. Caller of this function,
which is cifs_negotiate_protocol() requires that tcpStatus after successful
execution of negotiate callback stay in CifsInNegotiate. But if the
CIFSSMBNegotiate() called from cifs_negotiate() fails due to connection
issues then tcpStatus is changed as so repeated CIFSSMBNegotiate() call
does not help.

Fix this problem by moving retrying code from negotiate callback (which is
either cifs_negotiate() or smb2_negotiate()) to cifs_negotiate_protocol()
which is caller of those callbacks. This allows to properly handle and
implement correct transistions between tcpStatus states as function
cifs_negotiate_protocol() already handles it.

With this change, cifs_negotiate_protocol() now handles also -EAGAIN error
set by the RFC1002_NEGATIVE_SESSION_RESPONSE processing after reconnecting
with NetBIOS session.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 01:54:17 -05:00
Pali Rohár
665e187948 cifs: Improve handling of NetBIOS packets
Now all NetBIOS session logic is handled in ip_rfc1001_connect() function,
so cleanup is_smb_response() function which contains generic handling of
incoming SMB packets. Note that function is_smb_response() is not used
directly or indirectly (e.g. over cifs_demultiplex_thread() by
ip_rfc1001_connect() function.

Except the Negative Session Response and the Session Keep Alive packet, the
cifs_demultiplex_thread() should not receive any NetBIOS session packets.
And Session Keep Alive packet may be received only when the NetBIOS session
was established by ip_rfc1001_connect() function. So treat any such packet
as error and schedule reconnect.

Negative Session Response packet is returned from Windows SMB server (from
Windows 98 and also from Windows Server 2022) if client sent over port 139
SMB negotiate request without previously establishing a NetBIOS session.
The common scenario is that Negative Session Response packet is returned
for the SMB negotiate packet, which is the first one which SMB client
sends (if it is not establishing a NetBIOS session).

Note that server port 139 may be forwarded and mapped between virtual
machines to different number. And Linux SMB client do not call function
ip_rfc1001_connect() when prot is not 139. So nowadays when using port
mapping or port forwarding between VMs, it is not so uncommon to see this
error.

Currently the logic on Negative Session Response packet changes server port
to 445 and force reconnection. But this logic does not work when using
non-standard port numbers and also does not help if the server on specified
port is requiring establishing a NetBIOS session.

Fix this Negative Session Response logic and instead of changing server
port (on which server does not have to listen), force reconnection with
establishing a NetBIOS session.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 01:54:17 -05:00
Pali Rohár
7d14dd683b cifs: Allow to disable or force initialization of NetBIOS session
Currently SMB client always tries to initialize NetBIOS session when the
server port is 139. This is useful for default cases, but nowadays when
using non-standard routing or testing between VMs, it is common that
servers are listening on non-standard ports.

So add a new mount option -o nbsessinit and -o nonbsessinit which either
forces initialization or disables initialization regardless of server port
number.

This allows Linux SMB client to connect to older SMB1 server listening on
non-standard port, which requires initialization of NetBIOS session, by
using additional mount options -o port= and -o nbsessinit.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-04-01 01:54:17 -05:00