Commit graph

21 commits

Author SHA1 Message Date
Namjae Jeon
a89f5fae99 ksmbd: add free_transport ops in ksmbd connection
free_transport function for tcp connection can be called from smbdirect.
It will cause kernel oops. This patch add free_transport ops in ksmbd
connection, and add each free_transports for tcp and smbdirect.

Fixes: 21a4e47578 ("ksmbd: fix use-after-free in __smb2_lease_break_noti()")
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-17 16:26:44 -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
3aa660c059 ksmbd: prevent connection release during oplock break notification
ksmbd_work could be freed when after connection release.
Increment r_count of ksmbd_conn to indicate that requests
are not finished yet and to not release the connection.

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>
2025-03-10 12:54:32 -05:00
Marios Makassikis
43fb7bce88 ksmbd: fix broken transfers when exceeding max simultaneous operations
Since commit 0a77d947f5 ("ksmbd: check outstanding simultaneous SMB
operations"), ksmbd enforces a maximum number of simultaneous operations
for a connection. The problem is that reaching the limit causes ksmbd to
close the socket, and the client has no indication that it should have
slowed down.

This behaviour can be reproduced by setting "smb2 max credits = 128" (or
lower), and transferring a large file (25GB).

smbclient fails as below:

  $ smbclient //192.168.1.254/testshare -U user%pass
  smb: \> put file.bin
  cli_push returned NT_STATUS_USER_SESSION_DELETED
  putting file file.bin as \file.bin smb2cli_req_compound_submit:
  Insufficient credits. 0 available, 1 needed
  NT_STATUS_INTERNAL_ERROR closing remote file \file.bin
  smb: \> smb2cli_req_compound_submit: Insufficient credits. 0 available,
  1 needed

Windows clients fail with 0x8007003b (with smaller files even).

Fix this by delaying reading from the socket until there's room to
allocate a request. This effectively applies backpressure on the client,
so the transfer completes, albeit at a slower rate.

Fixes: 0a77d947f5 ("ksmbd: check outstanding simultaneous SMB operations")
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-12-15 22:20:03 -06:00
Marios Makassikis
83c47d9e0c ksmbd: count all requests in req_running counter
This changes the semantics of req_running to count all in-flight
requests on a given connection, rather than the number of elements
in the conn->request list. The latter is used only in smb2_cancel,
and the counter is not used

Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-12-15 22:20:03 -06:00
Namjae Jeon
db5f824306 ksmbd: add debug print for pending request during server shutdown
We need to know how many pending requests are left at the end of server
shutdown. That means we need to know how long the server will wait
to process pending requests in case of a server shutdown.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-25 18:58:27 -06:00
Namjae Jeon
f75f8bdd4f ksmbd: use msleep instaed of schedule_timeout_interruptible()
use msleep instaed of schedule_timeout_interruptible()
to guarantee the task delays as expected.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-25 18:58:26 -06:00
Namjae Jeon
0066f623bc ksmbd: use __GFP_RETRY_MAYFAIL
Prefer to report ENOMEM rather than incur the oom for allocations in
ksmbd. __GFP_NORETRY could not achieve that, It would fail the allocations
just too easily. __GFP_RETRY_MAYFAIL will keep retrying the allocation
until there is no more progress and fail the allocation instead go OOM
and let the caller to deal with it.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-11-25 18:58:02 -06:00
Namjae Jeon
0a77d947f5 ksmbd: check outstanding simultaneous SMB operations
If Client send simultaneous SMB operations to ksmbd, It exhausts too much
memory through the "ksmbd_work_cache”. It will cause OOM issue.
ksmbd has a credit mechanism but it can't handle this problem. This patch
add the check if it exceeds max credits to prevent this problem by assuming
that one smb request consumes at least one credit.

Cc: stable@vger.kernel.org # v5.15+
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>
2024-11-05 09:26:38 +09:00
Shen Lichuan
9e676e571d ksmbd: 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/common/smb2pdu.h:9: specfication ==> specification
fs/smb/common/smb2pdu.h:494: usally ==> usually
fs/smb/common/smb2pdu.h:1064: Attrubutes ==> Attributes
fs/smb/server/connection.c:28: cleand ==> cleaned
fs/smb/server/ksmbd_netlink.h:216: struture ==> structure
fs/smb/server/oplock.c:799: conains ==> contains
fs/smb/server/oplock.c:1487: containted ==> contained
fs/smb/server/server.c:282: proccessing ==> processing
fs/smb/server/smb_common.c:491: comforms ==> conforms
fs/smb/server/xattr.h:102: ATTRIBUITE ==> ATTRIBUTE

Signed-off-by: Shen Lichuan <shenlichuan@vivo.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-25 21:33:22 -05:00
Namjae Jeon
ee426bfb9d ksmbd: add refcnt to ksmbd_conn struct
When sending an oplock break request, opinfo->conn is used,
But freed ->conn can be used on multichannel.
This patch add a reference count to the ksmbd_conn struct
so that it can be freed when it is no longer used.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-14 00:03:15 -05:00
Namjae Jeon
76e98a158b ksmbd: fix race condition between destroy_previous_session() and smb2 operations()
If there is ->PreviousSessionId field in the session setup request,
The session of the previous connection should be destroyed.
During this, if the smb2 operation requests in the previous session are
being processed, a racy issue could happen with ksmbd_destroy_file_table().
This patch sets conn->status to KSMBD_SESS_NEED_RECONNECT to block
incoming  operations and waits until on-going operations are complete
(i.e. idle) before desctorying the previous session.

Fixes: c8efcc7861 ("ksmbd: add support for durable handles v1/v2")
Cc: stable@vger.kernel.org # v6.6+
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-25040
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-08-18 17:02:36 -05:00
Namjae Jeon
38d20c6290 ksmbd: fix UAF issue in ksmbd_tcp_new_connection()
The race is between the handling of a new TCP connection and
its disconnection. It leads to UAF on `struct tcp_transport` in
ksmbd_tcp_new_connection() function.

Cc: stable@vger.kernel.org
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-22991
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-14 11:39:49 -06:00
Kevin Hao
8fb7b72392 ksmbd: Add missing set_freezable() for freezable kthread
The kernel thread function ksmbd_conn_handler_loop() invokes
the try_to_freeze() in its loop. But all the kernel threads are
non-freezable by default. So if we want to make a kernel thread to be
freezable, we have to invoke set_freezable() explicitly.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-09 20:01:16 -06:00
Namjae Jeon
67797da8a4 ksmbd: no need to wait for binded connection termination at logoff
The connection could be binded to the existing session for Multichannel.
session will be destroyed when binded connections are released.
So no need to wait for that's connection at logoff.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-10-30 21:58:12 -05:00
Namjae Jeon
53ff5cf891 ksmbd: fix race condition between session lookup and expire
Thread A                        +  Thread B
 ksmbd_session_lookup            |  smb2_sess_setup
   sess = xa_load                |
                                 |
                                 |    xa_erase(&conn->sessions, sess->id);
                                 |
                                 |    ksmbd_session_destroy(sess) --> kfree(sess)
                                 |
   // UAF!                       |
   sess->last_active = jiffies   |
                                 +

This patch add rwsem to fix race condition between ksmbd_session_lookup
and ksmbd_expire_session.

Reported-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-10-04 20:21:48 -05:00
Namjae Jeon
73f949ea87 ksmbd: check iov vector index in ksmbd_conn_write()
If ->iov_idx is zero, This means that the iov vector for the response
was not added during the request process. In other words, it means that
there is a problem in generating a response, So this patch return as
an error to avoid NULL pointer dereferencing problem.

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-09-21 14:41:06 -05:00
Namjae Jeon
e2b76ab8b5 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>
2023-08-29 12:30:19 -05:00
Namjae Jeon
1c1bcf2d3e ksmbd: validate smb request protocol id
This patch add the validation for smb request protocol id.
If it is not one of the four ids(SMB1_PROTO_NUMBER, SMB2_PROTO_NUMBER,
SMB2_TRANSFORM_PROTO_NUM, SMB2_COMPRESSION_TRANSFORM_ID), don't allow
processing the request. And this will fix the following KASAN warning
also.

[   13.905265] BUG: KASAN: slab-out-of-bounds in init_smb2_rsp_hdr+0x1b9/0x1f0
[   13.905900] Read of size 16 at addr ffff888005fd2f34 by task kworker/0:2/44
...
[   13.908553] Call Trace:
[   13.908793]  <TASK>
[   13.908995]  dump_stack_lvl+0x33/0x50
[   13.909369]  print_report+0xcc/0x620
[   13.910870]  kasan_report+0xae/0xe0
[   13.911519]  kasan_check_range+0x35/0x1b0
[   13.911796]  init_smb2_rsp_hdr+0x1b9/0x1f0
[   13.912492]  handle_ksmbd_work+0xe5/0x820

Cc: stable@vger.kernel.org
Reported-by: Chih-Yen Chang <cc85nod@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-02 12:30:57 -05:00
Namjae Jeon
368ba06881 ksmbd: check the validation of pdu_size in ksmbd_conn_handler_loop
The length field of netbios header must be greater than the SMB header
sizes(smb1 or smb2 header), otherwise the packet is an invalid SMB packet.

If `pdu_size` is 0, ksmbd allocates a 4 bytes chunk to `conn->request_buf`.
In the function `get_smb2_cmd_val` ksmbd will read cmd from
`rcv_hdr->Command`, which is `conn->request_buf + 12`, causing the KASAN
detector to print the following error message:

[    7.205018] BUG: KASAN: slab-out-of-bounds in get_smb2_cmd_val+0x45/0x60
[    7.205423] Read of size 2 at addr ffff8880062d8b50 by task ksmbd:42632/248
...
[    7.207125]  <TASK>
[    7.209191]  get_smb2_cmd_val+0x45/0x60
[    7.209426]  ksmbd_conn_enqueue_request+0x3a/0x100
[    7.209712]  ksmbd_server_process_request+0x72/0x160
[    7.210295]  ksmbd_conn_handler_loop+0x30c/0x550
[    7.212280]  kthread+0x160/0x190
[    7.212762]  ret_from_fork+0x1f/0x30
[    7.212981]  </TASK>

Cc: stable@vger.kernel.org
Reported-by: Chih-Yen Chang <cc85nod@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-02 12:30:57 -05:00
Steve French
38c8a9a520 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>
2023-05-24 16:29:21 -05:00
Renamed from fs/ksmbd/connection.c (Browse further)