| Age | Commit message (Collapse) | Author |
|---|
|
Pull smb client fixes from Steve French:
- Fix for two ACL issues (security fix to validate dacloffset better
and chmod fix)
- Fix out of bounds reads (in check_wsl_eas and smb2_check_msg for
symlinks)
- Two Kerberos fixes including an important one when AES-256 encryption
chosen
- Fix open_cached_dir problem when directory leases disabled
* tag 'v7.1-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: validate dacloffset before building DACL pointers
smb/client: fix out-of-bounds read in smb2_compound_op()
smb/client: fix out-of-bounds read in symlink_data()
smb: client: Zero-pad short GSS session keys per MS-SMB2
smb: client: Use FullSessionKey for AES-256 encryption key derivation
smb: client: use kzalloc to zero-initialize security descriptor buffer
cifs: abort open_cached_dir if we don't request leases
|
|
parse_sec_desc(), build_sec_desc(), and the chown path in
id_mode_to_cifs_acl() all add the server-supplied dacloffset to pntsd
before proving a DACL header fits inside the returned security
descriptor.
On 32-bit builds a malicious server can return dacloffset near
U32_MAX, wrap the derived DACL pointer below end_of_acl, and then slip
past the later pointer-based bounds checks. build_sec_desc() and
id_mode_to_cifs_acl() can then dereference DACL fields from the wrapped
pointer in the chmod/chown rewrite paths.
Validate dacloffset numerically before building any DACL pointer and
reuse the same helper at the three DACL entry points.
Fixes: bc3e9dd9d104 ("cifs: Change SIDs in ACEs while transferring file ownership.")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
If a server sends a truncated response but a large OutputBufferLength, and
terminates the EA list early, check_wsl_eas() returns success without
validating that the entire OutputBufferLength fits within iov_len.
Then smb2_compound_op() does:
memcpy(idata->wsl.eas, data[0], size[0]);
Where size[0] is OutputBufferLength. If iov_len is smaller than size[0],
memcpy can read beyond the end of the rsp_iov allocation and leak adjacent
kernel heap memory.
Link: https://lore.kernel.org/linux-cifs/d998240c-aca9-420d-9dbd-f5ba24af19e0@chenxiaosong.com/
Fixes: ea41367b2a60 ("smb: client: introduce SMB2_OP_QUERY_WSL_EA")
Cc: stable@vger.kernel.org
Signed-off-by: Zisen Ye <zisenye@stu.xidian.edu.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Since smb2_check_message() returns success without length validation for
the symlink error response, in symlink_data() it is possible for
iov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer
only contains the base SMB2 header (64 bytes), accessing
err->ErrorContextCount (at offset 66) or err->ByteCount later in
symlink_data() will cause an out-of-bounds read.
Link: https://lore.kernel.org/linux-cifs/297d8d9b-adf7-42fd-a1c2-5b1f230032bc@chenxiaosong.com/
Fixes: 76894f3e2f71 ("cifs: improve symlink handling for smb2+")
Cc: Stable@vger.kernel.org
Signed-off-by: Zisen Ye <zisenye@stu.xidian.edu.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Per MS-SMB2 section 3.2.5.3, Session.SessionKey is the first 16 bytes
of the GSS cryptographic key, right-padded with zero bytes if the key
is shorter than 16 bytes.
SMB2_auth_kerberos() copies the GSS session key from the cifs.upcall
response using kmemdup(msg->data, msg->sesskey_len, ...) and stores
the GSS-reported length verbatim in ses->auth_key.len. generate_key()
reads SMB2_NTLMV2_SESSKEY_SIZE bytes from this buffer when feeding the
HMAC-SHA256 KDF for signing key derivation. If a GSS mechanism returns
a session key shorter than 16 bytes (e.g. a deprecated single-DES
Kerberos enctype with an 8-byte session key), the KDF call performs an
out-of-bounds slab read and derives keys that do not match the server,
which pads per the spec.
Modern KDCs disable short-key enctypes by default, so this is latent
rather than reachable in production, but it is still a kernel heap
over-read.
Allocate auth_key.response with kzalloc() at a length of
max(msg->sesskey_len, SMB2_NTLMV2_SESSKEY_SIZE), copy the GSS key in,
and rely on kzalloc()'s zero initialization for the spec-mandated
padding. Set ses->auth_key.len to the padded length. Larger GSS keys
(e.g. the 32-byte aes256-cts-hmac-sha1-96 session key) continue to be
stored at their natural length, preserving the FullSessionKey path.
Emit a cifs_dbg(VFS, ...) message when a short key is encountered to
surface deprecated-enctype usage.
NTLMv2 and NTLMSSP code paths produce a 16-byte session key by
construction and are unaffected.
Signed-off-by: Piyush Sachdeva <psachdeva@microsoft.com>
Signed-off-by: Piyush Sachdeva <s.piyush1024@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
When Kerberos authentication is used with AES-256 encryption (AES-256-CCM
or AES-256-GCM), the SMB3 encryption and decryption keys must be derived
using the full session key (Session.FullSessionKey) rather than just the
first 16 bytes (Session.SessionKey).
Per MS-SMB2 section 3.2.5.3.1, when Connection.Dialect is "3.1.1" and
Connection.CipherId is AES-256-CCM or AES-256-GCM, Session.FullSessionKey
must be set to the full cryptographic key from the GSS authentication
context. The encryption and decryption key derivation (SMBC2SCipherKey,
SMBS2CCipherKey) must use this FullSessionKey as the KDF input. The
signing key derivation continues to use Session.SessionKey (first 16
bytes) in all cases.
Previously, generate_key() hardcoded SMB2_NTLMV2_SESSKEY_SIZE (16) as the
HMAC-SHA256 key input length for all derivations. When Kerberos with
AES-256 provides a 32-byte session key, the KDF for encryption/decryption
was using only the first 16 bytes, producing keys that did not match the
server's, causing mount failures with sec=krb5 and require_gcm_256=1.
Add a full_key_size parameter to generate_key() and pass the appropriate
size from generate_smb3signingkey():
- Signing: always SMB2_NTLMV2_SESSKEY_SIZE (16 bytes)
- Encryption/Decryption: ses->auth_key.len when AES-256, otherwise 16
Also fix cifs_dump_full_key() to report the actual session key length for
AES-256 instead of hardcoded CIFS_SESS_KEY_SIZE, so that userspace tools
like Wireshark receive the correct key for decryption.
Cc: <stable@vger.kernel.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Piyush Sachdeva <psachdeva@microsoft.com>
Signed-off-by: Piyush Sachdeva <s.piyush1024@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Commit 62e7dd0a39c2d ("smb: common: change the data type of num_aces
to le16") split struct smb_acl's __le32 num_aces field into __le16
num_aces and __le16 reserved. The reserved field corresponds to Sbz2
in the MS-DTYP ACL wire format, which must be zero [1].
When building an ACL descriptor in build_sec_desc(), we are using a
kmalloc()'ed descriptor buffer and writing the fields explicitly using
le16() writes now. This never writes to the 2 byte reserved field,
leaving it as uninitialized heap data.
When the reserved field happens to contain non-zero slab garbage,
Samba rejects the security descriptor with "ndr_pull_security_descriptor
failed: Range Error", causing chmod to fail with EINVAL.
Change kmalloc() to kzalloc() to ensure the entire buffer is
zero-initialized.
Fixes: 62e7dd0a39c2d ("smb: common: change the data type of num_aces to le16")
Cc: stable@vger.kernel.org
Signed-off-by: Bjoern Doebel <doebel@amazon.de>
Assisted-by: Kiro:claude-opus-4.6
[1] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/20233ed8-a6c6-4097-aafa-dd545ed24428
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
It is possible that SMB2_open_init may not set lease context based
on the requested oplock level. This can happen when leases have been
temporarily or permanently disabled. When this happens, we will have
open_cached_dir making an open without lease context and the response
will anyway be rejected by open_cached_dir (thereby forcing a close to
discard this open). That's unnecessary two round-trips to the server.
This change adds a check before making the open request to the server
to make sure that SMB2_open_init did add the expected lease context
to the open in open_cached_dir.
Cc: <stable@vger.kernel.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
smb_inherit_dacl() walks the parent directory DACL loaded from the
security descriptor xattr. It verifies that each ACE contains the fixed
SID header before using it, but does not verify that the variable-length
SID described by sid.num_subauth is fully contained in the ACE.
A malformed inheritable ACE can advertise more subauthorities than are
present in the ACE. compare_sids() may then read past the ACE.
smb_set_ace() also clamps the copied destination SID, but used the
unchecked source SID count to compute the inherited ACE size. That could
advance the temporary inherited ACE buffer pointer and nt_size accounting
past the allocated buffer.
Fix this by validating the parent ACE SID count and SID length before
using the SID during inheritance. Compute the inherited ACE size from the
copied SID so the size matches the bounded destination SID. Reject the
inherited DACL if size accumulation would overflow smb_acl.size or the
security descriptor allocation size.
Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Shota Zaizen <s@zaizen.me>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
The kernel test robot reported W=1 build warnings for ksmbd_conn_get()
and ksmbd_conn_put() due to missing parameter descriptions.
Add the @conn description to fix these warnings.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Non-pipe shares must have a duplicated backing path before they can be
published. share_config_request() currently calls kstrndup() for that
path, but if the allocation fails it leaves ret unchanged. If veto list
parsing succeeds and share->name exists, the partially built share is
still inserted into the global share table with share->path left NULL.
A later share-root SMB2 create uses tree_conn->share_conf->path as the
lookup root. If the share was published with path == NULL, that request
passes a NULL pathname into do_getname_kernel()/strlen() and can crash
the ksmbd worker.
Set ret = -ENOMEM when path duplication fails so the incomplete share is
destroyed before publication.
Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Signed-off-by: Shuhao Fu <sfual@cse.ust.hk>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
ksmbd_durable_scavenger() has two related races against any walker
that iterates f_ci->m_fp_list, including ksmbd_lookup_fd_inode()
(used by ksmbd_vfs_rename) and the share-mode checks in
fs/smb/server/smb_common.c.
(1) fp->node list-head reuse. Durable-preserved handles can remain
linked on f_ci->m_fp_list after session teardown so share-mode checks
still see them while the handle is reconnectable. The scavenger
collected expired handles by adding fp->node to a local
scavenger_list after removing them from the global durable idr.
Because fp->node is the same list_head used by m_fp_list,
list_add(&fp->node, &scavenger_list) overwrites the m_fp_list links
and corrupts both lists. CONFIG_DEBUG_LIST can report this on the
share-mode walk path.
(2) Refcount race against m_fp_list walkers. The scavenger qualifies
an expired durable handle with atomic_read(&fp->refcount) > 1 and
fp->conn under global_ft.lock, removes fp from global_ft, then drops
global_ft.lock before unlinking fp from m_fp_list and freeing it.
During that gap fp is still linked on m_fp_list with f_state ==
FP_INITED. ksmbd_lookup_fd_inode() under m_lock read calls
ksmbd_fp_get() (atomic_inc_not_zero on refcount that is still 1) and
takes a live reference; the scavenger then unlinks and frees fp
while the holder owns a reference, leading to UAF on the holder's
subsequent ksmbd_fd_put() and on any field reads performed by a
concurrent share-mode walker that iterates m_fp_list without taking
ksmbd_fp_get() (smb_check_perm_dleases-like paths).
Fix both:
* Stop reusing fp->node as a scavenger-private list node. Remove
one expired handle from global_ft under global_ft.lock, take an
explicit transient reference, drop the lock, unlink fp->node
from m_fp_list under f_ci->m_lock, then drop both the durable
lifetime and transient references with atomic_sub_and_test(2,
&fp->refcount). If the scavenger is the last putter the close
runs there; otherwise an in-flight holder that already raced
through the m_fp_list lookup owns the final close via its
ksmbd_fd_put() path. The one-at-a-time disposal can rescan the
durable idr when multiple handles expire in the same pass, but
durable scavenging is a background expiration path and the final
full scan recomputes min_timeout before the next wait.
* Clear fp->persistent_id inside __ksmbd_remove_durable_fd() right
after idr_remove(), so a delayed final close from a holder that
snatched fp does not re-issue idr_remove() on a persistent id
that idr_alloc_cyclic() in ksmbd_open_durable_fd() may have
already handed out to a brand-new durable handle.
* Bypass the per-conn open_files_count decrement in
__put_fd_final() when fp is detached from any session table
(fp->conn cleared by session_fd_check() at durable preserve --
paired with the volatile_id clear at unpublish, so checking
fp->conn alone is sufficient). The walker that owns the final
close runs from an unrelated work->conn whose
stats.open_files_count never tracked this durable fp; without
this guard the holder would underflow that unrelated counter.
The two races are folded into one patch because patch (1) alone
cleans up the corrupted list but leaves a deterministic UAF window
for m_fp_list walkers that the transient-reference and
persistent_id discipline in (2) close; bisecting onto an
intermediate state would land on a UAF that pre-patch chaos merely
made less reproducible.
Validation:
* CONFIG_DEBUG_LIST coverage for the list_head reuse path.
* KASAN-enabled direct SMB2 durable-handle coverage that exercised
ksmbd_durable_scavenger() and non-NULL ksmbd_lookup_fd_inode()
returns while durable handles expired under concurrent rename
lookups, with no KASAN, UAF, list-corruption, ODEBUG, or WARNING
reports.
* checkpatch --strict
* make -j$(nproc) M=fs/smb/server
Fixes: d484d621d40f ("ksmbd: add durable scavenger timer")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
__close_file_table_ids() is the per-session teardown that closes every
fp belonging to a session (or to one tree connect on that session) by
walking the session's volatile-id idr. The current loop has three
related problems on busy or racing workloads:
* Sleeping under ft->lock. The session-teardown skip callback,
session_fd_check(), already sleeps in ksmbd_vfs_copy_durable_owner()
-> kstrdup(GFP_KERNEL) and down_write(&fp->f_ci->m_lock) (a
rw_semaphore). Running the callback inside write_lock(&ft->lock)
trips CONFIG_DEBUG_ATOMIC_SLEEP / CONFIG_PROVE_LOCKING on a
durable-fd workload.
* Refcount accounting blind to f_state. The unconditional
atomic_dec_and_test(&fp->refcount) does not distinguish
FP_INITED (idr-owned reference still intact) from FP_CLOSED (an
earlier ksmbd_close_fd() already consumed the idr-owned reference
while leaving fp in the idr because a holder kept refcount
non-zero). When the latter races with teardown the same path
over-decrements into a holder reference and ksmbd_fd_put() later
UAFs that holder.
* FP_NEW window. Between __open_id() publishing fp into the
session idr and ksmbd_update_fstate(..., FP_INITED) committing the
transition at the end of smb2_open(), an fp is in FP_NEW and an
intervening teardown that takes a transient reference and
unpublishes the volatile id leaves the original idr-owned
reference orphaned -- the opener is unaware that fp has been
unpublished, returns success to the client, and the fp leaks at
refcount = 1.
Refactor __close_file_table_ids() to take a transient reference on fp
and unpublish fp from the session idr *under ft->lock* before calling
skip() outside the lock. A transient ref protects lifetime but not
concurrent field mutation, so the idr_remove() is what keeps
__ksmbd_lookup_fd() through this session's idr from granting a new
ksmbd_fp_get() reference to an fp whose fp->conn / fp->tcon /
fp->volatile_id / op->conn / lock_list links are about to be rewritten
by session_fd_check(). Durable reconnect is unaffected because it
reaches fp through the global durable table (ksmbd_lookup_durable_fd
-> global_ft).
Decide n_to_drop together with any FP_INITED -> FP_CLOSED transition
under ft->lock so teardown and ksmbd_close_fd() never both consume the
idr-owned reference. See ksmbd_mark_fp_closed() for the per-state
accounting. For the FP_NEW path to be safe, the opener has to learn
that fp was unpublished: ksmbd_update_fstate() now returns -ENOENT
when an FP_NEW -> FP_INITED transition finds f_state already advanced
or the volatile id cleared (both committed by teardown under
ft->lock); smb2_open() propagates that as STATUS_OBJECT_NAME_INVALID
and drops the original reference via ksmbd_fd_put().
The list removal cannot be left for a deferred final putter because
fp->volatile_id has already been cleared and __ksmbd_remove_fd() will
intentionally skip both idr_remove() and list_del_init(). Move the
m_fp_list unlink in __ksmbd_remove_fd() above the volatile-id check so
that an FP_NEW fp that happened to be added to m_fp_list (smb2_open()
adds fp->node before ksmbd_update_fstate() runs) is still cleaned up
on the deferred putter path; list_del_init() on an empty node is a
no-op and remains safe for fps that were never added.
Add a defensive guard in session_fd_check() that refuses non-FP_INITED
fps so that even if a teardown reaches an FP_NEW fp it falls into the
close branch (where the n_to_drop = 1 accounting keeps the opener's
reference alive) instead of the durable-preserve branch (which mutates
fp->conn / fp->tcon).
Validation on a debug kernel additionally built with CONFIG_DEBUG_LIST
and CONFIG_DEBUG_OBJECTS_WORK used a same-session two-tcon workload
(open/write storm on one tcon, 50 tree disconnects on the other) and
reported no list-corruption, work_struct ODEBUG, sleep-in-atomic,
lockdep or kmemleak reports. Reverting only the
__close_file_table_ids() hunk while keeping a forced-is_reconnectable()
harness produced the expected sleep-in-atomic at vfs_cache.c:1095,
confirming the ft->lock-out-of-sleepable-skip discipline.
KASAN-enabled direct SMB2 coverage with durable handles enabled
exercised ksmbd_close_tree_conn_fds(), ksmbd_close_session_fds(),
the FP_NEW failure path, tree_conn_fd_check(), and a non-zero
session_fd_check() durable-preserve return. This produced no KASAN,
DEBUG_LIST, ODEBUG, or WARNING reports.
Fixes: f44158485826 ("cifsd: add file operations")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
ksmbd_conn_free() is one of four sites that can observe the last
refcount drop of a struct ksmbd_conn. The other three
fs/smb/server/connection.c ksmbd_conn_r_count_dec()
fs/smb/server/oplock.c __free_opinfo()
fs/smb/server/vfs_cache.c session_fd_check()
end the conn with a bare kfree(), skipping
ida_destroy(&conn->async_ida) and
conn->transport->ops->free_transport(conn->transport). Whenever one
of them is the last putter, the embedded async_ida and the entire
transport struct leak -- for TCP, that is also the struct socket and
the kvec iov.
__free_opinfo() being a final putter is not theoretical. opinfo_put()
queues the callback via call_rcu(&opinfo->rcu, free_opinfo_rcu), so
ksmbd_server_terminate_conn() can deposit N opinfo releases in RCU and
have ksmbd_conn_free() run in the handler thread before any of them
fire. ksmbd_conn_free() then observes refcnt > 0 and short-circuits;
the last RCU-delivered __free_opinfo() falls onto its bare kfree(conn)
branch and the transport is lost.
A/B validation in a QEMU/virtme guest, mounting //127.0.0.1/testshare:
each iteration holds 8 files open via sleep processes, force-closes
TCP with "ss -K sport = :445", kills the holders, lazy-umounts;
repeated 10 times, then ksmbd shutdown and kmemleak scan.
state conn_alloc conn_free tcp_free opi_rcu kmemleak
---------- ---------- --------- -------- ------- --------
pre-patch 20 20 10 160 7
with patch 20 20 20 160 0
Pre-patch conn_free=20 with tcp_free=10 directly demonstrates the
bare-kfree paths skipping transport cleanup; kmemleak backtraces point
into struct tcp_transport / iov. With this patch tcp_free matches
conn_free at 20/20 and kmemleak is clean.
Move the per-struct final release into __ksmbd_conn_release_work() and
route the three bare-kfree final-put sites through a new
ksmbd_conn_put(). Those sites now pair ida_destroy() and
free_transport() with kfree(conn) regardless of which holder happens
to release the last reference. stop_sessions() only triggers the
transport shutdown and does not itself drop the last conn reference,
so it is unaffected.
The centralized release reaches sock_release() -> tcp_close() ->
lock_sock_nested() (might_sleep) from every final putter, including
__free_opinfo() invoked from an RCU softirq callback, which trips
CONFIG_DEBUG_ATOMIC_SLEEP. Defer the release to a dedicated
ksmbd_conn_wq workqueue so ksmbd_conn_put() is safe from any
non-sleeping context.
Make ksmbd_file own a strong connection reference while fp->conn is
non-NULL so durable-preserve and final-close paths cannot dereference
a stale connection. ksmbd_open_fd() and ksmbd_reopen_durable_fd()
take the reference via ksmbd_conn_get() (the latter also reorders the
fp->conn / fp->tcon assignments before __open_id() so the published fp
is never observed with fp->conn == NULL); session_fd_check() and
__ksmbd_close_fd() drop it via ksmbd_conn_put(). With that invariant,
session_fd_check() can take a local conn pointer once and use it
across the m_op_list and lock_list iterations even though op->conn
puts may otherwise drop the last reference.
At module exit the workqueue is flushed and destroyed after
rcu_barrier(), so any release queued by a trailing RCU callback is
drained before the inode hash and module text go away.
Fixes: ee426bfb9d09 ("ksmbd: add refcnt to ksmbd_conn struct")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
ib_dma_map_sg() modifies the provided scatterlist and returns the
number of mapped entries, which can be fewer than the requested
mr->sgt.nents if the DMA controller coalesces contiguous memory
segments. Passing the original, uncoalesced count to ib_map_mr_sg()
causes memory registration failures if coalescing actually occurs.
Capture the actual mapped count returned by ib_dma_map_sg() and pass it
to ib_map_mr_sg() to ensure correct MR registration.
Also update the ib_dma_map_sg() error logging to drop the error
pointer formatting, since the return value is an integer count
rather than an error code.
Ensure a proper error code (-EIO) is assigned when DMA mapping or
MR registration fails.
Fixes: de5ef8ec3c46 ("smb: smbdirect: introduce smbdirect_mr.c with client mr code")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221408
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Yi Kuo <yi@yikuo.dev>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
This makes it easier to rebuild cifs.ko and ksmbd.ko against
a running kernel.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/linux-cifs/aehrPuY60VMcYGU8@infradead.org/
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
This is a better solution than
EXPORT_SYMBOL_FOR_MODULES(__sym, "cifs,ksmbd") as it makes
it possible to rebuild smbdirect.ko against a
running kernel and then load the existing cifs.ko and ksmbd.ko
from the running kernel.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/linux-cifs/aehrPuY60VMcYGU8@infradead.org/
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Pull smb server fixes from Steve French:
- Fix shutdown (stop sessions)
- Fix readdir unsupported info level
* tag 'v7.1-rc2-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: rewrite stop_sessions() with restartable iteration
smb: server: handle readdir_info_level_struct_sz() error
|
|
Today we skip calling change_conf for negotiates and session setup
requests. This can be a problem for mchan as the immediate next call
after session setup could be due to an I/O that is made on the
mount point. For single channel, this is not a problem as
there will be several calls after setting up session.
This change enforces calling change_conf when the total credits contain
enough for reservations for echoes and oplocks. We expect this to happen
during the last session setup response. This way, echoes and oplocks are
not disabled before the first request to the server. So if that first
request is an open, it does not need to disable requesting leases.
Cc: <stable@vger.kernel.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Currently, smb2_compound_op() allocates
struct smb2_compound_vars *vars using GFP_ATOMIC, although
smb2_compound_op() can sleep when it calls compound_send_recv()
before vars is freed.
Allocate vars using GFP_KERNEL.
Signed-off-by: Fredric Cover <fredric.cover.lkernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
stop_sessions() walks conn_list with hash_for_each() and, for every
entry, drops conn_list_lock across the transport ->shutdown() call
before re-acquiring the read lock to continue the loop. The hash
walk relies on cross-iteration state (the current bucket and the
hlist position), which is not preserved across unlock/relock: if
another thread performs a list mutation during the unlocked window,
the ongoing iteration becomes unreliable and can re-visit
connections that have already been handled or skip connections that
have not. The outer `if (!hash_empty(conn_list)) goto again;` retry
masks the symptom in the common case but does not address the
unsafe iteration itself.
Reframe the loop so it never relies on iterator state across
unlock/relock. Under conn_list_lock held for read, pick the first
connection whose ->shutdown() has not yet been issued by this path,
pin it by taking an extra reference, record that fact on the
connection and mark it EXITING while still inside the locked walk,
then drop the lock. Then call ->shutdown() outside the lock, drop
the pin (freeing the connection if the handler already released its
reference), and restart from the top.
Use a new per-connection flag, conn->stop_called, as the "shutdown
issued from stop_sessions()" marker rather than reusing the status
state. ksmbd_conn_set_exiting() is also invoked by
ksmbd_sessions_deregister() on sibling channels of a multichannel
session without issuing a transport shutdown, so treating
KSMBD_SESS_EXITING as "already handled here" would skip connections
that still need shutdown() to wake their handler out of recv(),
leaving the outer retry waiting indefinitely for the hash to drain.
stop_sessions() is serialised by init_lock in
ksmbd_conn_transport_destroy(), so writing stop_called under the
read lock has no other writer.
Set EXITING inside the locked walk so the selection, the stop_called
marker, and the status transition all happen together, and guard
against regressing a connection that has already advanced to
KSMBD_SESS_RELEASING on its own (for example, if the handler exited
its receive loop for an unrelated reason between teardown steps).
When the pin drop is the last put, release the transport and pair
ida_destroy(&target->async_ida) with the ida_init() done in
ksmbd_conn_alloc(), so stop_sessions() retiring a connection on its
own does not leak the xarray backing of the embedded async_ida.
The outer retry with msleep() is kept to wait for handler threads to
reach ksmbd_conn_free() and drain the hash.
Observed with an instrumented build that logs one line per visit and
widens the unlocked window before ->shutdown() by 200 ms, under
five concurrent cifs mounts (nosharesock, one connection each):
* Current code: the same connection address is revisited many
times during a single stop_sessions() call and ->shutdown() is
invoked well beyond the number of live connections before the
hash finally drains.
* Rewritten code: each live connection produces exactly one
->shutdown() call; the function returns as soon as the hash is
empty.
Functional teardown via `ksmbd.control --shutdown` with the same
five mounts completes cleanly on the rewritten path.
Performance is observably unchanged. Tearing down N concurrent
nosharesock cifs connections with `ksmbd.control --shutdown` +
`rmmod ksmbd` takes essentially the same wall time before and after
the rewrite:
N before after
10 4.93s 5.34s
30 7.34s 7.03s
50 7.31s 7.01s (3-run avg: 7.04s vs 7.25s)
100 6.98s 6.78s
200 6.77s 6.89s
and the number of ->shutdown() calls equals the number of live
connections on both paths when the race is not widened. The
teardown is dominated by the msleep(100)-based outer retry waiting
for handler threads to run ksmbd_conn_free(), not by the iteration
itself; the restartable loop's worst-case O(N^2) visit cost is in
the microseconds even at N=200 and sits far below the msleep(100)
granularity.
Applied alone on top of ksmbd-for-next-next, this patch does not
introduce a new leak site. Under the same reproducer (10x
concurrent-holders + ss -K + ksmbd.control --shutdown + rmmod), the
tree still shows the pre-existing per-connection transport leak
count that arises when the last refcount drop lands in one of
ksmbd_conn_r_count_dec(), __free_opinfo() or session_fd_check() -
all of which end with a bare kfree() today. kmemleak backtraces
for the unreferenced objects point into the TCP accept path
(sk_clone -> inet_csk_clone_lock, sock_alloc_inode) and none
involve stop_sessions(). Plugging those bare-kfree sites is the
responsibility of the follow-up patch.
Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
early exit in smb2_populate_readdir_entry() if the requested info_level
is unknown.
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Commit abdb1742a3123 ("cifs: get rid of mount options string parsing")
removed the last caller.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Pull more smb server updates from Steve French:
- move fs/smb/common/smbdirect to fs/smb/smbdirect
- change signature calc to use AES-CMAC library, simpler and faster
- invalid signature fix
- multichannel fix
- open create options fix
- fix durable handle leak
- cap maximum lock count to avoid potential denial of service
- four connection fixes: connection free and session destroy IDA fixes,
refcount fix, connection leak fix, max_connections off by one fix
- IPC validation fix
- fix out of bounds write in getting xattrs
- fix use after free in durable handle reconnect
- three ACL fixes: fix potential ACL overflow, harden num_aces check,
and fix minimum ACE size check
* tag 'v7.1-rc-part2-ksmbd-fixes' of git://git.samba.org/ksmbd:
smb: smbdirect: move fs/smb/common/smbdirect/ to fs/smb/smbdirect/
smb: server: stop sending fake security descriptors
ksmbd: scope conn->binding slowpath to bound sessions only
ksmbd: fix CreateOptions sanitization clobbering the whole field
ksmbd: fix durable fd leak on ClientGUID mismatch in durable v2 open
ksmbd: fix O(N^2) DoS in smb2_lock via unbounded LockCount
ksmbd: destroy async_ida in ksmbd_conn_free()
ksmbd: destroy tree_conn_ida in ksmbd_session_destroy()
ksmbd: Use AES-CMAC library for SMB3 signature calculation
ksmbd: reset rcount per connection in ksmbd_conn_wait_idle_sess_id()
ksmbd: fix out-of-bounds write in smb2_get_ea() EA alignment
ksmbd: use check_add_overflow() to prevent u16 DACL size overflow
ksmbd: fix use-after-free in smb2_open during durable reconnect
ksmbd: validate num_aces and harden ACE walk in smb_inherit_dacl()
smb: server: fix max_connections off-by-one in tcp accept path
ksmbd: require minimum ACE size in smb_check_perm_dacl()
ksmbd: validate response sizes in ipc_validate_msg()
smb: server: fix active_num_conn leak on transport allocation failure
|
|
git://git.samba.org/sfrench/cifs-2.6
Pull smb client fixes from Steve French:
- Four bug fixes: OOB read in ioctl query info, 3 ACL fixes
- SMB1 Unix extensions mount fix
- Four crypto improvements: move to AES-CMAC library, simpler and faster
- Remove drop_dir_cache to avoid potential crash, and move to /procfs
- Seven SMB3.1.1 compression fixes
* tag 'v7.1-rc1-part3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: Drop 'allocate_crypto' arg from smb*_calc_signature()
smb: client: Make generate_key() return void
smb: client: Remove obsolete cmac(aes) allocation
smb: client: Use AES-CMAC library for SMB3 signature calculation
smb: common: add SMB3_COMPRESS_MAX_ALGS
smb: client: compress: add code docs to lz77.c
smb: client: compress: LZ77 optimizations
smb: client: compress: increase LZ77_MATCH_MAX_DIST
smb: client: compress: fix counting in LZ77 match finding
smb: client: compress: fix buffer overrun in lz77_compress()
smb: client: scope end_of_dacl to CIFS_DEBUG2 use in parse_dacl
smb: client: fix (remove) drop_dir_cache module parameter
smb: client: require a full NFS mode SID before reading mode bits
smb: client: validate the whole DACL before rewriting it in cifsacl
smb: client: fix OOB read in smb2_ioctl_query_info QUERY_INFO path
cifs: update internal module version number
smb: client: compress: fix bad encoding on last LZ77 flag
smb: client: fix dir separator in SMB1 UNIX mounts
|
|
This also removes the smbdirect_ prefix from the files.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/linux-cifs/CAHk-=whmue3PVi88K0UZLZO0at22QhQZ-yu+qO2TOKyZpGqecw@mail.gmail.com/
Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Since the crypto library API is now being used instead of crypto_shash,
all structs for MAC computation are now just fixed-size structs
allocated on the stack; no dynamic allocations are ever required.
Besides being much more efficient, this also means that the
'allocate_crypto' argument to smb2_calc_signature() and
smb3_calc_signature() is no longer used. Remove this unused argument.
Acked-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Since the crypto library API is now being used instead of crypto_shash,
generate_key() can no longer fail. Make it return void and simplify the
callers accordingly.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Since the crypto library API is now being used instead of crypto_shash,
the "cmac(aes)" crypto_shash that is being allocated and stored in
'struct cifs_secmech' is no longer used. Remove it.
That makes the kconfig selection of CRYPTO_CMAC and the module softdep
on "cmac" unnecessary. So remove those too.
Finally, since this removes the last use of crypto_shash from the smb
client, also remove the remaining crypto_shash-related helper functions.
Note: cifs_unicode.c was relying on <linux/unaligned.h> being included
transitively via <crypto/internal/hash.h>. Since the latter include is
removed, make cifs_unicode.c include <linux/unaligned.h> explicitly.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Convert smb3_calc_signature() to use the AES-CMAC library instead of a
"cmac(aes)" crypto_shash.
The result is simpler and faster code. With the library there's no need
to allocate memory, no need to handle errors except for key preparation,
and the AES-CMAC code is accessed directly without inefficient indirect
calls and other unnecessary API overhead.
For now a "cmac(aes)" crypto_shash is still being allocated in
'struct cifs_secmech'. Later commits will remove that, simplifying the
code even further.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Set it to number of currently defined algorithms (6 as of now).
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Document parts of the code, especially the apparently
non-sense parts.
Other:
- change pointer increment constants to sizeof() values
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
This patch implements several micro-optimizations on lz77_compress()
with the goal of reducing the number of instructions per [input]
byte (a.k.a. IPB).
Changes:
- change hashtable to be u32 (instead of u64) -- change the hash
function to reflect that (adds lz77_hash() and lz77_read32() helpers)
- batch-write literals instead of 1 by 1 -- now that we have a well
defined hot path (match finding) and a cold path (encode literals +
match), batch writing makes a significant difference
- implement adaptive skipping of input bytes -- skip input bytes more
aggressively if too few matches are being found
- name some constants for more meaningful context
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Increase max distance (i.e. window size) from 1k to 8k.
This allows better compression and is just as fast.
Other:
- drop LZ77_MATCH_MIN_DIST as it's nused -- main loop
already checks if dist > 0
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
- lz77_match_len() increments @cur before checking for equality,
leading to off-by-one match len in some cases.
Fix by moving pointers increment to inside the loop.
Also rename @wnd arg to @match (more accurate name).
- both lz77_match_len() and lz77_compress() checked for
"buf + step < end" when the correct is "<=" for such cases.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
@dst buffer is allocated with same size as @src, which, for good
compression cases, works fine.
However, when compression goes bad (e.g. random bytes payloads), the
compressed size can increase significantly, and even by stopping the
main loop at 7/8 of @slen, writing leftover literals could write past
the end of @dst because of LZ77 metadata.
To fix this, add lz77_compressed_alloc_size() helper to compute the
correct allocation size for @dst, accounting for metadata and worst
cast scenario (all literals).
While this is overprovisioning memory, it's not only correct, but also
allows lz77_compress() main loop to run without ever checking @dst
limits (i.e. a perf improvement).
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
After validate_dacl() was factored out in commit 149822e5541c, the
local end_of_dacl in parse_dacl() is only read by the dump_ace()
call under #ifdef CONFIG_CIFS_DEBUG2. With CIFS_DEBUG2 off the
variable is assigned but never used, which gcc -W=1 flags as
-Wunused-but-set-variable.
Remove the local and compute the end-of-dacl pointer inline at the
single call site inside the existing CIFS_DEBUG2 guard. No
functional change: when CIFS_DEBUG2 is enabled the argument value
is identical to what the removed local carried; when CIFS_DEBUG2
is disabled the code was already dead.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202604220046.tGkRxVtS-lkp@intel.com/
Fixes: 149822e5541c ("smb: client: validate the whole DACL before rewriting it in cifsacl")
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Being a module parameter, it's possible to do:
# modprobe cifs drop_dir_cache=1
Which will lead to a crash, because cifs_tcp_ses_list hasn't been
initialized yet:
[ 168.242624] BUG: kernel NULL pointer dereference, address: 0000000000000010
[ 168.242952] #PF: supervisor read access in kernel mode
[ 168.243175] #PF: error_code(0x0000) - not-present page
[ 168.243394] PGD 0 P4D 0
[ 168.243524] Oops: Oops: 0000 [#1] SMP NOPTI
[ 168.243703] CPU: 2 UID: 0 PID: 1105 Comm: modprobe Not tainted 7.0.0-lku #5 PREEMPT(lazy)
[ 168.244054] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-2-g4f253b9b-prebuilt.qemu.org 04/01/2014
[ 168.244557] RIP: 0010:cifs_param_set_drop_dir_cache+0x7c/0x100 [cifs]
...
[ 168.248785] Call Trace:
[ 168.248915] <TASK>
[ 168.249023] parse_args+0x285/0x3a0
[ 168.249204] ? __pfx_unknown_module_param_cb+0x10/0x10
[ 168.249448] load_module+0x192b/0x1bb0
[ 168.249637] ? __pfx_unknown_module_param_cb+0x10/0x10
[ 168.249882] ? kernel_read_file+0x27d/0x2b0
[ 168.250088] init_module_from_file+0xce/0xf0
[ 168.250291] idempotent_init_module+0xfb/0x2f0
[ 168.250496] __x64_sys_finit_module+0x5a/0xa0
[ 168.250694] do_syscall_64+0xe0/0x5a0
[ 168.250863] ? exc_page_fault+0x65/0x160
[ 168.251050] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 168.251284] RIP: 0033:0x7fcaa12b774d
Instead of fixing this with some kind of "is module initialized"
approach, this patch instead moves that functionality to procfs,
setting a write op for the existing open_dirs entry, where
writing a 0 to it will drop the cached directory entries.
Also make it available only when CONFIG_CIFS_DEBUG=y.
A small change needed now is to not call flush_delayed_work()
on invalidate_all_cached_dirs() when called from procfs (can't sleep in
that context).
So add a @sync arg to invalidate_all_cached_dirs() to control when to
flush the delayed works.
Fixes: dde6667fa3c8 ("smb: client: add drop_dir_cache module parameter to invalidate cached dirents")
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
parse_dacl() treats an ACE SID matching sid_unix_NFS_mode as an NFS
mode SID and reads sid.sub_auth[2] to recover the mode bits.
That assumes the ACE carries three subauthorities, but compare_sids()
only compares min(a, b) subauthorities. A malicious server can return
an ACE with num_subauth = 2 and sub_auth[] = {88, 3}, which still
matches sid_unix_NFS_mode and then drives the sub_auth[2] read four
bytes past the end of the ACE.
Require num_subauth >= 3 before treating the ACE as an NFS mode SID.
This keeps the fix local to the special-SID mode path without changing
compare_sids() semantics for the rest of cifsacl.
Fixes: e2f8fbfb8d09 ("cifs: get mode bits from special sid on stat")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
build_sec_desc() and id_mode_to_cifs_acl() derive a DACL pointer from a
server-supplied dacloffset and then use the incoming ACL to rebuild the
chmod/chown security descriptor.
The original fix only checked that the struct smb_acl header fits before
reading dacl_ptr->size or dacl_ptr->num_aces. That avoids the immediate
header-field OOB read, but the rewrite helpers still walk ACEs based on
pdacl->num_aces with no structural validation of the incoming DACL body.
A malicious server can return a truncated DACL that still contains a
header, claims one or more ACEs, and then drive
replace_sids_and_copy_aces() or set_chmod_dacl() past the validated
extent while they compare or copy attacker-controlled ACEs.
Factor the DACL structural checks into validate_dacl(), extend them to
validate each ACE against the DACL bounds, and use the shared validator
before the chmod/chown rebuild paths. parse_dacl() reuses the same
validator so the read-side parser and write-side rewrite paths agree on
what constitutes a well-formed incoming DACL.
Fixes: bc3e9dd9d104 ("cifs: Change SIDs in ACEs while transferring file ownership.")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4-6
Assisted-by: Codex:gpt-5-4
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
smb2_ioctl_query_info() has two response-copy branches: PASSTHRU_FSCTL
and the default QUERY_INFO path. The QUERY_INFO branch clamps
qi.input_buffer_length to the server-reported OutputBufferLength and then
copies qi.input_buffer_length bytes from qi_rsp->Buffer to userspace, but
it never verifies that the flexible-array payload actually fits within
rsp_iov[1].iov_len.
A malicious server can return OutputBufferLength larger than the actual
QUERY_INFO response, causing copy_to_user() to walk past the response
buffer and expose adjacent kernel heap to userspace.
Guard the QUERY_INFO copy with a bounds check on the actual Buffer
payload. Use struct_size(qi_rsp, Buffer, qi.input_buffer_length)
rather than an open-coded addition so the guard cannot overflow on
32-bit builds.
Fixes: f5778c398713 ("SMB3: Allow SMB3 FSCTL queries to be sent to server from tools")
Cc: stable@vger.kernel.org
Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com>
Assisted-by: Claude:claude-opus-4-6
Assisted-by: Codex:gpt-5-4
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
in smb2_get_info_sec, a dummy security descriptor (SD) is returned if
the requested information is not supported.
the code is currently wrong, as DACL_PROTECTED is set in the type field,
but there is no DACL is present.
instead of faking a security, report a STATUS_NOT_SUPPORTED error.
this seems to fix a "Error 0x80090006: Invalid Signature" on file
transfers with Windows 11 clients (25H2, build 26200.8246).
capturing traffic shows that the client is sending a GET_INFO/SEC_INFO
request, with the additional_info field set to 0x20
(ATTRIBUTE_SECURITY_INFORMATION). Returning an empty SD
(with only SELF_RELATIVE set) does not fix the error.
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
When the binding SESSION_SETUP sets conn->binding = true, the flag stays
set after the call so that the global session lookup in
ksmbd_session_lookup_all() can find the session, which was not added to
conn->sessions. Because the flag is connection-wide, the global lookup
path will also resolve any other session by id if asked.
Tighten the global lookup so that the returned session must have this
connection registered in its channel xarray (sess->ksmbd_chann_list).
The channel entry is installed by the existing binding_session path in
ntlm_authenticate()/krb5_authenticate() when a SESSION_SETUP completes
successfully, so this condition is a strict equivalent of "this
connection has been accepted as a channel of this session". Connections
that have not bound to a given session cannot reach it via the global
table.
The existing conn->binding gate for entering the slowpath is preserved
so that non-binding connections keep the fast-path-only behavior, and
the session->state check is unchanged.
Fixes: f5a544e3bab7 ("ksmbd: add support for SMB3 multichannel")
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
smb2_open() attempts to clear conflicting CreateOptions bits
(FILE_SEQUENTIAL_ONLY_LE together with FILE_RANDOM_ACCESS_LE, and
FILE_NO_COMPRESSION_LE on a directory open), but uses a plain
assignment of the bitwise negation of the target flag:
req->CreateOptions = ~(FILE_SEQUENTIAL_ONLY_LE);
req->CreateOptions = ~(FILE_NO_COMPRESSION_LE);
This replaces the entire field with 0xFFFFFFFB / 0xFFFFFFEF rather
than clearing a single bit. With the SEQUENTIAL/RANDOM case, the
next check for FILE_OPEN_BY_FILE_ID_LE | CREATE_TREE_CONNECTION |
FILE_RESERVE_OPFILTER_LE then trivially matches and a legitimate
request is rejected with -EOPNOTSUPP. With the NO_COMPRESSION case,
every downstream test (FILE_DELETE_ON_CLOSE, etc.) operates on a
corrupted CreateOptions value.
Use &= ~FLAG to clear only the intended bit in both places.
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
ksmbd_lookup_fd_cguid() returns a ksmbd_file with its refcount
incremented via ksmbd_fp_get(). parse_durable_handle_context() in
the DURABLE_REQ_V2 case properly releases this reference on every
path inside the ClientGUID-match branch, either by calling
ksmbd_put_durable_fd() or by transferring ownership to dh_info->fp
for a successful reconnect. However, when an entry exists in the
global file table with the same CreateGuid but a different
ClientGUID, the code simply falls through to the new-open path
without dropping the reference obtained from ksmbd_lookup_fd_cguid().
Per MS-SMB2 section 3.3.5.9.10 ("Handling the
SMB2_CREATE_DURABLE_HANDLE_REQUEST_V2 Create Context"), the server
MUST locate an Open whose Open.CreateGuid matches the request's
CreateGuid AND whose Open.ClientGuid matches the ClientGuid of the
connection that received the request. If no such Open is found, the
server MUST continue with the normal open execution phase. A
CreateGuid hit with a ClientGUID mismatch is therefore the
"Open not found" case: proceeding with a new open is correct, but
the reference obtained purely as a side effect of the lookup must
not be leaked.
Repeated requests that hit this mismatch pin global_ft entries,
prevent __ksmbd_close_fd() from ever running for the corresponding
files, and defeat the durable scavenger, leading to long-lived
resource leaks.
Release the reference in the mismatch path and clear dh_info->fp so
subsequent logic does not mistake a non-matching lookup result for
a reconnect target.
Fixes: c8efcc786146 ("ksmbd: add support for durable handles v1/v2")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
smb2_lock() performs O(N^2) conflict detection with no cap on LockCount.
Cap lock_count at 64 to prevent CPU exhaustion from a single request.
Signed-off-by: Akif Sait <akif.sait111@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
When per-connection async_ida was converted from a dynamically
allocated ksmbd_ida to an embedded struct ida, ksmbd_ida_free() was
removed from the connection teardown path but no matching
ida_destroy() was added. The connection is therefore freed with the
IDA's backing xarray still intact.
The kernel IDA API expects ida_init() and ida_destroy() to be paired
over an object's lifetime, so add the missing cleanup before the
connection is freed.
No leak has been observed in testing; this is a pairing fix to match
the IDA lifetime rules, not a response to a reproduced regression.
Fixes: d40012a83f87 ("cifsd: declare ida statically")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
When per-session tree_conn_ida was converted from a dynamically
allocated ksmbd_ida to an embedded struct ida, ksmbd_ida_free() was
removed from ksmbd_session_destroy() but no matching ida_destroy()
was added. The session is therefore freed with the IDA's backing
xarray still intact.
The kernel IDA API expects ida_init() and ida_destroy() to be paired
over an object's lifetime, so add the missing cleanup before the
enclosing session is freed.
Also move ida_init() to right after the session is allocated so that
it is always paired with the destroy call even on the early error
paths of __session_create() (ksmbd_init_file_table() or
__init_smb2_session() failures), both of which jump to the error
label and invoke ksmbd_session_destroy() on a partially initialised
session.
No leak has been observed in testing; this is a pairing fix to match
the IDA lifetime rules, not a response to a reproduced regression.
Fixes: d40012a83f87 ("cifsd: declare ida statically")
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
Now that AES-CMAC has a library API, convert ksmbd_sign_smb3_pdu() to
use it instead of a "cmac(aes)" crypto_shash.
The result is simpler and faster code. With the library there's no need
to dynamically allocate memory, no need to handle errors, and the
AES-CMAC code is accessed directly without inefficient indirect calls
and other unnecessary API overhead.
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
|
rcount is intended to be connection-specific: 2 for curr_conn, 1 for
every other connection sharing the same session. However, it is
initialised only once before the hash iteration and is never reset.
After the loop visits curr_conn, later sibling connections are also
checked against rcount == 2, so a sibling with req_running == 1 is
incorrectly treated as idle. This makes the outcome depend on the
hash iteration order: whether a given sibling is checked against the
loose (< 2) or the strict (< 1) threshold is decided by whether it
happens to be visited before or after curr_conn.
The function's contract is "wait until every connection sharing this
session is idle" so that destroy_previous_session() can safely tear
the session down. The latched rcount violates that contract and
reopens the teardown race window the wait logic was meant to close:
destroy_previous_session() may proceed before sibling channels have
actually quiesced, overlapping session teardown with in-flight work
on those connections.
Recompute rcount inside the loop so each connection is compared
against its own threshold regardless of iteration order.
This is a code-inspection fix for an iteration-order-dependent logic
error; a targeted reproducer would require SMB3 multichannel with
in-flight work on a sibling channel landing after curr_conn in hash
order, which is not something that can be triggered reliably.
Fixes: 76e98a158b20 ("ksmbd: fix race condition between destroy_previous_session() and smb2 operations()")
Cc: stable@vger.kernel.org
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
|
