ksmbd disconnect connection when mounting with vers=smb1.
ksmbd should send smb1 negotiate response to client for correct
unsupported error return. This patch add needed SMB1 macros and fill
NegProt part of the response for smb1 negotiate response.
Cc: stable@vger.kernel.org
Reported-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ksmbd returned "Input/output error" when mounting with vers=2.0 to
ksmbd. It should return STATUS_NOT_SUPPORTED on unsupported smb2.0
dialect.
Cc: stable@vger.kernel.org
Reported-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
A common exploit pattern for ROP attacks is to abuse prepare_kernel_cred()
in order to construct escalated privileges[1]. Instead of providing a
short-hand argument (NULL) to the "daemon" argument to indicate using
init_cred as the base cred, require that "daemon" is always set to
an actual task. Replace all existing callers that were passing NULL
with &init_task.
Future attacks will need to have sufficiently powerful read/write
primitives to have found an appropriately privileged task and written it
to the ROP stack as an argument to succeed, which is similarly difficult
to the prior effort needed to escalate privileges before struct cred
existed: locate the current cred and overwrite the uid member.
This has the added benefit of meaning that prepare_kernel_cred() can no
longer exceed the privileges of the init task, which may have changed from
the original init_cred (e.g. dropping capabilities from the bounding set).
[1] https://google.com/search?q=commit_creds(prepare_kernel_cred(0))
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steve French <sfrench@samba.org>
Cc: Ronnie Sahlberg <lsahlber@redhat.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: "Michal Koutný" <mkoutny@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: linux-nfs@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Russ Weight <russell.h.weight@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Link: https://lore.kernel.org/r/20221026232943.never.775-kees@kernel.org
A kernel daemon should not rely on the current thread, which is unknown
and might be malicious. Before this security fix,
ksmbd_override_fsids() didn't correctly override FS UID/GID which means
that arbitrary user space threads could trick the kernel to impersonate
arbitrary users or groups for file system access checks, leading to
file system access bypass.
This was found while investigating truncate support for Landlock:
https://lore.kernel.org/r/CAKYAXd8fpMJ7guizOjHgxEyyjoUwPsx3jLOPZP=wPYcbhkVXqA@mail.gmail.com
Fixes: e2f34481b2 ("cifsd: add server-side procedures for SMB3")
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Steve French <smfrench@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Link: https://lore.kernel.org/r/20220929100447.108468-1-mic@digikod.net
Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
outstanding credits must be initialized to 0,
because it means the sum of credits consumed by
in-flight requests.
And outstanding credits must be compared with
total credits in smb2_validate_credit_charge(),
because total credits are the sum of credits
granted by ksmbd.
This patch fix the following error,
while frametest with Windows clients:
Limits exceeding the maximum allowable outstanding requests,
given : 128, pending : 8065
Fixes: b589f5db6d ("ksmbd: limits exceeding the maximum allowable outstanding requests")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Reported-by: Yufan Chen <wiz.chen@gmail.com>
Tested-by: Yufan Chen <wiz.chen@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
ksmbd sets the inode number to UniqueId. However, the same UniqueId for
dot and dotdot entry is set to the inode number of the parent inode.
This patch set them using the current inode and parent inode.
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
To move smb2_hdr to smbfs_common, This patch remove smb2_buf_length
variable in smb2_hdr. Also, declare smb2_get_msg function to get smb2
request/response from ->request/response_buf.
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Use ksmbd_req_buf_next() in ksmbd_verify_smb_message().
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Ralph Boehme <slow@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although ksmbd doesn't send SMB2.0 support in supported dialect list of smb
negotiate response, There is the leftover of smb2.0 dialect.
This patch remove it not to support SMB2.0 in ksmbd.
Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch add MAX_STREAM_PROT_LEN macro and check if stream protocol
length exceeds maximum value. opencode pdu size check in
ksmbd_pdu_size_has_room().
Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch add validation to check request buffer check in smb2
negotiate and fix null pointer deferencing oops in smb3_preauth_hash_rsp()
that found from manual test.
Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
In smb_common.c you have this function : ksmbd_smb_request() which
is called from connection.c once you have read the initial 4 bytes for
the next length+smb2 blob.
It checks the first byte of this 4 byte preamble for valid values,
i.e. a NETBIOSoverTCP SESSION_MESSAGE or a SESSION_KEEP_ALIVE.
We don't need to check this for ksmbd since it only implements SMB2
over TCP port 445.
The netbios stuff was only used in very old servers when SMB ran over
TCP port 139.
Now that we run over TCP port 445, this is actually not a NB header anymore
and you can just treat it as a 4 byte length field that must be less
than 16Mbyte. and remove the references to the RFC1002 constants that no
longer applies.
Cc: Tom Talpey <tom@talpey.com>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Ralph Böhme <slow@samba.org>
Cc: Steve French <smfrench@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
When second smb2 pdu has invalid protocol id, ksmbd doesn't detect it
and allow to process smb2 request. This patch add the check it in
ksmbd_verify_smb_message() and don't use protocol id of smb2 request as
protocol id of response.
Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Reviewed-by: Ralph Böhme <slow@samba.org>
Reported-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
When transferring ownership information to the
client the k*ids are translated into raw *ids before they are sent over
the wire. The function currently erroneously translates the k*ids
according to the mount's idmapping. Instead, reporting the owning *ids
to userspace the underlying k*ids need to be mapped up in the caller's
user namespace. This is how stat() works.
The caller in this instance is ksmbd itself and ksmbd always runs in the
initial user namespace. Translate according to that.
The idmapping of the mount is already taken into account by the lower
filesystem and so kstat->*id will contain the mapped k*ids.
Switch to from_k*id_munged() which ensures that the overflow*id is
returned instead of the (*id_t)-1 when the k*id can't be translated.
Cc: Steve French <stfrench@microsoft.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
To negotiate either the SMB2 protocol or SMB protocol, a client must
send a SMB_COM_NEGOTIATE message containing the list of dialects it
supports, to which the server will respond with either a
SMB_COM_NEGOTIATE or a SMB2_NEGOTIATE response.
The current implementation responds with the highest common dialect,
rather than looking explicitly for "SMB 2.???" and "SMB 2.002", as
indicated in [MS-SMB2]:
[MS-SMB2] 3.3.5.3.1:
If the server does not implement the SMB 2.1 or 3.x dialect family,
processing MUST continue as specified in 3.3.5.3.2.
Otherwise, the server MUST scan the dialects provided for the dialect
string "SMB 2.???". If the string is not present, continue to section
3.3.5.3.2. If the string is present, the server MUST respond with an
SMB2 NEGOTIATE Response as specified in 2.2.4.
[MS-SMB2] 3.3.5.3.2:
The server MUST scan the dialects provided for the dialect string "SMB
2.002". If the string is present, the client understands SMB2, and the
server MUST respond with an SMB2 NEGOTIATE Response.
This is an issue if a client attempts to negotiate SMB3.1.1 using
a SMB_COM_NEGOTIATE, as it will trigger the following NULL pointer
dereference:
8<--- cut here ---
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 1917455e
[00000000] *pgd=00000000
Internal error: Oops: 17 [#1] ARM
CPU: 0 PID: 60 Comm: kworker/0:1 Not tainted 5.4.60-00027-g0518c02b5c5b #35
Hardware name: Marvell Kirkwood (Flattened Device Tree)
Workqueue: ksmbd-io handle_ksmbd_work
PC is at ksmbd_gen_preauth_integrity_hash+0x24/0x190
LR is at smb3_preauth_hash_rsp+0x50/0xa0
pc : [<802b7044>] lr : [<802d6ac0>] psr: 40000013
sp : bf199ed8 ip : 00000000 fp : 80d1edb0
r10: 80a3471b r9 : 8091af16 r8 : 80d70640
r7 : 00000072 r6 : be95e198 r5 : ca000000 r4 : b97fee00
r3 : 00000000 r2 : 00000002 r1 : b97fea00 r0 : b97fee00
Flags: nZcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user
Control: 0005317f Table: 3e7f4000 DAC: 00000055
Process kworker/0:1 (pid: 60, stack limit = 0x3dd1fdb4)
Stack: (0xbf199ed8 to 0xbf19a000)
9ec0: b97fee00 00000000
9ee0: be95e198 00000072 80d70640 802d6ac0 b3da2680 b97fea00 424d53ff be95e140
9f00: b97fee00 802bd7b0 bf10fa58 80128a78 00000000 000001c8 b6220000 bf0b7720
9f20: be95e198 80d0c410 bf7e2a00 00000000 00000000 be95e19c 80d0c370 80123b90
9f40: bf0b7720 be95e198 bf0b7720 bf0b7734 80d0c410 bf198000 80d0c424 80d116e0
9f60: bf10fa58 801240c0 00000000 bf10fa40 bf1463a0 bf198000 bf0b7720 80123ed0
9f80: bf077ee4 bf10fa58 00000000 80127f80 bf1463a0 80127e88 00000000 00000000
9fa0: 00000000 00000000 00000000 801010d0 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[<802b7044>] (ksmbd_gen_preauth_integrity_hash) from [<802d6ac0>] (smb3_preauth_hash_rsp+0x50/0xa0)
[<802d6ac0>] (smb3_preauth_hash_rsp) from [<802bd7b0>] (handle_ksmbd_work+0x348/0x3f8)
[<802bd7b0>] (handle_ksmbd_work) from [<80123b90>] (process_one_work+0x160/0x200)
[<80123b90>] (process_one_work) from [<801240c0>] (worker_thread+0x1f0/0x2e4)
[<801240c0>] (worker_thread) from [<80127f80>] (kthread+0xf8/0x10c)
[<80127f80>] (kthread) from [<801010d0>] (ret_from_fork+0x14/0x24)
Exception stack(0xbf199fb0 to 0xbf199ff8)
9fa0: 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
Code: e1855803 e5d13003 e1855c03 e5903094 (e1d330b0)
---[ end trace 8d03be3ed09e5699 ]---
Kernel panic - not syncing: Fatal exception
smb3_preauth_hash_rsp() panics because conn->preauth_info is only allocated
when processing a SMB2 NEGOTIATE request.
Fix this by splitting the smb_protos array into two, each containing
only SMB1 and SMB2 dialects respectively.
While here, make ksmbd_negotiate_smb_dialect() static as it not
called from anywhere else.
Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Append ksmbd_lock into the connection's
lock list and the ksmbd_file's lock list.
And when a file is closed, detach ksmbd_lock
from these lists and free it.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Avoid calling mnt_user_ns() many time in
a function.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christian Brauner <christian@brauner.io>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For user namespace support, call vfs functions
with struct user_namespace got from struct path.
This patch have been tested mannually as below.
Create an id-mapped mount using the mount-idmapped utility
(https://github.com/brauner/mount-idmapped).
$ mount-idmapped --map-mount b:1003:1002:1 /home/foo <EXPORT DIR>/foo
(the user, "foo" is 1003, and the user "bar" is 1002).
And mount the export directory using cifs with the user, "bar".
succeed to create/delete/stat/read/write files and directory in
the <EXPORT DIR>/foo. But fail with a bind mount for /home/foo.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Opencode to remove FP_INODE macro.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move fs/cifsd to fs/ksmbd and rename the remaining cifsd name to ksmbd.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Namjae Jeon