linux-toradex.git/fs/smb/server, branch master

ksmbd: keep compound responses on query info errors

2026-09-15T13:28:52+00:00

Do not reset the RFC1002 length of the complete response when a query
info buffer is too small. The current command will add its error response
through ksmbd_iov_pin_rsp(), while resetting the base length can truncate
earlier responses in a compound request.

This lets ksmbd return the earlier responses and the query-info error
response together. Remove the now-unused rsp_org parameter from the pipe
query-info helpers.

Fixes: e2b76ab8b5c9 ("ksmbd: add support for read compound")
Reported-by: Mobin Aydinfar 
Reviewed-by: ChenXiaoSong 
Signed-off-by: Namjae Jeon

ksmbd: fix partial normalized name responses

2026-09-15T13:28:51+00:00

Windows may request FILE_NORMALIZED_NAME_INFORMATION with an output
buffer that only fits the fixed portion of the variable-length response.
Treat the fixed portion as FILE_NORMALIZED_NAME_INFORMATION_SIZE so ksmbd
returns STATUS_BUFFER_OVERFLOW instead of STATUS_INFO_LENGTH_MISMATCH.

This avoids rejecting valid partial normalized-name responses.

Fixes: 6b8b79226bc3 ("ksmbd: fix partial file information responses")
Reported-by: Mobin Aydinfar 
Reviewed-by: ChenXiaoSong 
Signed-off-by: Namjae Jeon

ksmbd: follow SMB2 session expiration semantics

2026-09-14T11:14:35+00:00

ksmbd_session_register() destroys valid sessions after ten seconds of
inactivity whenever a client starts another SessionSetup exchange. This
confuses Session.IdleTime with Session.ExpirationTime. Windows can create
additional authenticated sessions on an existing connection, so deleting
the older session invalidates its tree connects and makes mapped drives
fail with STATUS_NETWORK_NAME_DELETED.

The session expiration rules require the server to change a valid session
to expired only after its credential expiration time passes. A valid or
expired session otherwise keeps its connection from being scavenged.
Connections that have not negotiated a dialect, have no sessions, or have
only InProgress sessions are disconnected after an implementation-specific
timeout. Use the Windows-compatible 45 second value and run the expiration
check periodically for both TCP and SMB Direct.

Keep zero as an infinite credential expiration time, and count each
Valid-to-Expired transition. Set expired sessions to InProgress when they
reauthenticate. If authentication fails, remove the session from the
global and per-connection tables immediately, including SMB3 multichannel
connections.

Retain protection against abandoned SessionId-zero exchanges by allowing
only one InProgress authentication per connection. Additional exchanges
fail with STATUS_INSUFFICIENT_RESOURCES, and stale InProgress sessions are
reaped after the same 45 second setup timeout. This bounds the original
unauthenticated memory-exhaustion path without evicting established
sessions.

Fixes: ea174a918939 ("ksmbd: destroy expired sessions")
Reported-by: Mobin Aydinfar 
Signed-off-by: Namjae Jeon

treewide: refresh kmalloc_obj() conversions

2026-09-05T04:37:00+00:00

This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook

ksmbd: fix tree connection use-after-free in smb2_tree_connect()

2026-09-02T08:58:35+00:00

ksmbd_tree_conn_connect() publishes a new tree connection in
sess->tree_conns with a single reference and returns its pointer to
smb2_tree_connect(). The handler continues to initialize the object and
build the response after publication. A concurrent session logoff can
erase the connection and drop that reference, freeing the object while
the handler still uses it.

BUG: KASAN: slab-use-after-free in smb2_tree_connect+0xe3d/0xf90
  smb2_tree_connect (fs/smb/server/smb2pdu.c:2872)
  handle_ksmbd_work
  process_one_work
  worker_thread
  kthread

After xa_store() succeeds, take a second reference before releasing
tree_conns_lock. The original reference belongs to the xarray entry and
the second belongs to the creating smb2_tree_connect() handler.

Keep the references balanced in every path:

- On normal exit or an error after publication, smb2_tree_connect()
  drops its creator reference. Error cleanup also calls
  ksmbd_tree_conn_disconnect(), which drops the xarray reference only if
  it removes the exact entry.
- SMB2 TREE_DISCONNECT uses the same helper to remove the entry and drop
  its xarray reference. The request's existing lookup reference remains
  owned by the request and is released by the existing cleanup.
- Session LOGOFF removes each entry and drops its xarray reference. If
  it wins the race, later cleanup sees that the entry is gone and does
  not drop that reference again.

To enforce this ownership, claim the disconnected state and erase the
exact entry atomically under tree_conns_lock. This guarantees one drop
for the xarray reference and one drop by each in-flight user, regardless
of which teardown path wins. If logoff removes the entry before
initialization completes, fail the connect instead of marking the
detached object TREE_CONNECTED.

Fixes: 33b235a6e6eb ("ksmbd: fix race condition between tree conn lookup and disconnect")
Reported-by: Xiang Mei (Microsoft) 
Cc: AutonomousCodeSecurity@microsoft.com
Cc: stable@vger.kernel.org
Signed-off-by: Cen Zhang (Microsoft Security FORGE Labs) 
Signed-off-by: Namjae Jeon

ksmbd: validate COPYCHUNK source and target ranges

2026-09-02T08:58:15+00:00

ksmbd_vfs_copy_file_ranges() rejects negative source offsets in the
copy loop, but it does not validate target offsets. It also calculates
lock and overlap endpoints before ensuring that either range fits within
MAX_LFS_FILESIZE.

When the target is an alternate data stream, the buffered path passes a
negative target offset to ksmbd_vfs_stream_write(). Let n be Length and
let -d be TargetOffset, where 0 < d < n <= XATTR_SIZE_MAX. For an empty
stream, the writer allocates n - d bytes, then copies n bytes starting d
bytes before the allocation. An authenticated SMB client can control d
and the source data, overwrite kernel heap memory, and crash the host.

Validate both ranges before lock, overlap, or I/O calculations.

Fixes: 8482150a0743 ("ksmbd: support copychunk for alternate data streams")
Assisted-by: Antiproof:GPT-5.6-Sol
Signed-off-by: Alon Shakevsky 
Signed-off-by: Namjae Jeon

ksmbd: fix use-after-free in oplock break notification

2026-09-02T08:58:11+00:00

smb2_oplock_break_noti() reads opinfo->conn without any lock and
dereferences it after two allocations which may sleep.  When the
durable handle owning the oplock is disconnected, session_fd_check()
clears opinfo->conn and drops its conn reference under ci->m_lock, and
the last ksmbd_conn_put() frees the connection.  A break triggered by
another connection that races with the teardown can then resurrect the
freed connection: ksmbd_conn_get() is a plain atomic_inc, and the
queued break work later dereferences the stale conn via
ksmbd_conn_write(), a use-after-free reachable by any authenticated
client holding a durable batch oplock.

Thread the caller's inode into the notification path instead of taking
a new reference on it.  Every caller of oplock_break() already holds a
live ksmbd_file (or an explicit ksmbd_inode_lookup_lock() reference,
in the parent lease break paths) on the inode that owns the break
target's oplock list, so ci cannot be freed during the call, and its
lock can be taken without dereferencing opinfo->o_fp, which a
concurrent close may free.  Select and pin the connection under
ci->m_lock, the same lock session_fd_check() and
ksmbd_reopen_durable_fd() use to update opinfo->conn, so a concurrent
detach either loses the race to the clear or keeps the connection
alive until the notification work releases it.  Transfer the reference
to the work item and release it on allocation failures.

Fixes: b003086d7696 ("ksmbd: fix NULL-deref of opinfo->conn in oplock/lease break notifiers")
Cc: stable@vger.kernel.org
Signed-off-by: Abdifatah Suruur 
Signed-off-by: Namjae Jeon

ksmbd: fix sparc build with atomic work state

2026-09-02T08:58:00+00:00

Use an unsigned int for the work state so xchg() uses a supported
4-byte operation on sparc.

Fixes: d12168084c8c ("ksmbd: safely drain sessions during logoff")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202609021157.8f7Wx34I-lkp@intel.com/
Signed-off-by: Namjae Jeon

ksmbd: validate normalized name response length

2026-08-31T10:27:36+00:00

FILE_NORMALIZED_NAME_INFORMATION converts the open file path to UTF-16.
smb2_allocate_rsp_buf() leaves these responses in the 448-byte small
buffer, and get_file_normalized_name_info() converts the path without
checking the remaining space.

An authenticated client can query a long path and make
smbConvertToUTF16() write beyond work->response_buf.

Use the large response buffer for normalized-name queries. Before
conversion, verify that the response has room for the worst-case UTF-16
output and its terminator.

Fixes: 10aeff72ab82 ("ksmbd: support normalized name information")
Assisted-by: Antiproof:GPT-5.6-Sol
Signed-off-by: Alon Shakevsky 
Signed-off-by: Namjae Jeon

ksmbd: fix listener task lifetime on netdev events

2026-08-31T10:27:11+00:00

The listener thread exits when its listening socket is shutdown. The
netdevice notifier shuts down the socket before calling kthread_stop(), so
the task_struct can be freed before kthread_stop() gets its reference.

Create the listener in a stopped state and hold an extra task_struct
reference until kthread_stop_put() completes. Also stop and release
listeners before freeing their interface records during TCP teardown.

Fixes: 3316a8fc840d ("ksmbd: server: avoid busy polling in accept loop")
Reported-by: Farhad Alemi 
Signed-off-by: Namjae Jeon