11 Commits

Author SHA1 Message Date
Paulo Alcantara
348a04a8d1 smb: client: get rid of dfs code dep in namespace.c
Make namespace.c being built without requiring
CONFIG_CIFS_DFS_UPCALL=y by moving set_dest_addr() to dfs.c and call
it at the beginning of dfs_mount_share() so it can chase the DFS link
starting from the correct server in @ctx->dstaddr.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-20 16:05:50 -05:00
Paulo Alcantara
ce04127c58 smb: client: ensure to try all targets when finding nested links
With current implementation, when a nested DFS link is found during
mount(2), the client follows the referral and then try to connect to
all of its targets.  If all targets failed, the client bails out
rather than retrying remaining targets from previous referral.

Fix this by stacking all referrals and targets so the client can retry
remaining targets from previous referrals in case all targets of
current referral have failed.

Thanks to samba, this can be easily tested like below

* Run the following under dfs folder in samba server

  $ ln -s "msdfs:srv\\bad-share" link1
  $ ln -s "msdfs:srv\\dfs\\link1,srv\\good-share" link0

* Before patch

  $ mount.cifs //srv/dfs/link0 /mnt -o ...
  mount error(2): No such file or directory
  Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)...

* After patch

  $ mount.cifs //srv/dfs/link0 /mnt -o ...
  # ls /mnt
  bar  fileshare1  sub

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-20 16:05:50 -05:00
Paulo Alcantara
3fea12f3c6 smb: client: introduce DFS_CACHE_TGT_LIST()
Add new helper which declares and initialises target list of a DFS
referral rather having to do both separately.

No functional changes.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-20 16:05:49 -05:00
Paulo Alcantara
11260c3d60 smb: client: fix dfs link mount against w2k8
Customer reported that they couldn't mount their DFS link that was
seen by the client as a DFS interlink -- special form of DFS link
where its single target may point to a different DFS namespace -- and
it turned out that it was just a regular DFS link where its referral
header flags missed the StorageServers bit thus making the client
think it couldn't tree connect to target directly without requiring
further referrals.

When the DFS link referral header flags misses the StoraServers bit
and its target doesn't respond to any referrals, then tree connect to
it.

Fixes: a1c0d00572fc ("cifs: share dfs connections and supers")
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-02 13:36:12 -05:00
Paulo Alcantara
bf99f6be2d smb: client: fix missed ses refcounting
Use new cifs_smb_ses_inc_refcount() helper to get an active reference
of @ses and @ses->dfs_root_ses (if set).  This will prevent
@ses->dfs_root_ses of being put in the next call to cifs_put_smb_ses()
and thus potentially causing an use-after-free bug.

Fixes: 8e3554150d6c ("cifs: fix sharing of DFS connections")
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-07-12 23:29:39 -05:00
Colin Ian King
dfbf0ee092 smb: client: remove redundant pointer 'server'
The pointer 'server' is assigned but never read, the pointer is
redundant and can be removed. Cleans up clang scan build warning:

fs/smb/client/dfs.c:217:3: warning: Value stored to 'server' is
never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-07-01 00:21:17 -05:00
Paulo Alcantara
5f2a0afa98 smb: client: improve DFS mount check
Some servers may return error codes from REQ_GET_DFS_REFERRAL requests
that are unexpected by the client, so to make it easier, assume
non-DFS mounts when the client can't get the initial DFS referral of
@ctx->UNC in dfs_mount_share().

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-28 15:49:02 -05:00
Paulo Alcantara
3ae872de41 smb: client: fix shared DFS root mounts with different prefixes
When having two DFS root mounts that are connected to same namespace,
same mount options but different prefix paths, we can't really use the
shared @server->origin_fullpath when chasing DFS links in them.

Move the origin_fullpath field to cifs_tcon structure so when having
shared DFS root mounts with different prefix paths, and we need to
chase any DFS links, dfs_get_automount_devname() will pick up the
correct full path out of the @tcon that will be used for the new
mount.

Before patch

  mount.cifs //dom/dfs/dir /mnt/1 -o ...
  mount.cifs //dom/dfs /mnt/2 -o ...
  # shared server, ses, tcon
  # server: origin_fullpath=//dom/dfs/dir

  # @server->origin_fullpath + '/dir/link1'
  $ ls /mnt/2/dir/link1
  ls: cannot open directory '/mnt/2/dir/link1': No such file or directory

After patch

  mount.cifs //dom/dfs/dir /mnt/1 -o ...
  mount.cifs //dom/dfs /mnt/2 -o ...
  # shared server & ses
  # tcon_1: origin_fullpath=//dom/dfs/dir
  # tcon_2: origin_fullpath=//dom/dfs

  # @tcon_2->origin_fullpath + '/dir/link1'
  $ ls /mnt/2/dir/link1
  dir0  dir1  dir10  dir3  dir5  dir6  dir7  dir9  target2_file.txt  tsub

Fixes: 8e3554150d6c ("cifs: fix sharing of DFS connections")
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-28 15:48:43 -05:00
Paulo Alcantara
49024ec879 smb: client: fix parsing of source mount option
Handle trailing and leading separators when parsing UNC and prefix
paths in smb3_parse_devname().  Then, store the sanitised paths in
smb3_fs_context::source.

This fixes the following cases

$ mount //srv/share// /mnt/1 -o ...
$ cat /mnt/1/d0/f0
cat: /mnt/1/d0/f0: Invalid argument

The -EINVAL was returned because the client sent SMB2_CREATE "\\d0\f0"
rather than SMB2_CREATE "\d0\f0".

$ mount //srv//share /mnt/1 -o ...
mount: Invalid argument

The -EINVAL was returned correctly although the client only realised
it after sending a couple of bad requests rather than bailing out
earlier when parsing mount options.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-28 11:48:56 -05:00
Shyam Prasad N
91f4480c41 cifs: fix status checks in cifs_tree_connect
The ordering of status checks at the beginning of
cifs_tree_connect is wrong. As a result, a tcon
which is good may stay marked as needing reconnect
infinitely.

Fixes: 2f0e4f034220 ("cifs: check only tcon status on tcon related functions")
Cc: stable@vger.kernel.org # 6.3
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-06-11 20:52:48 -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