smb: client: fix potential UAF in cifs_dump_full_key()

Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: add dynamic trace point for ioctls

It can be helpful in debugging to know which ioctls are called to better
correlate them with smb3 fsctls (and opens). Add a dynamic trace point
to trace ioctls into cifs.ko

Here is sample output:

TASK-PID CPU# ||||| TIMESTAMP FUNCTION
| | | ||||| | |
new-inotify-ioc-90418 [001] ..... 142157.397024: smb3_ioctl: xid=18 fid=0x0 ioctl cmd=0xc009cf0b
new-inotify-ioc-90457 [007] ..... 142217.943569: smb3_ioctl: xid=22 fid=0x389bf5b6 ioctl cmd=0xc009cf0b

Signed-off-by: Steve French <stfrench@microsoft.com>

Missing field not being returned in ioctl CIFS_IOC_GET_MNT_INFO

The tcon_flags field was always being set to zero in the information
about the mount returned by the ioctl CIFS_IOC_GET_MNT_INFO instead
of being set to the value of the Flags field in the tree connection
structure as intended.

Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

smb3: allow dumping session and tcon id to improve stats analysis and debugging

When multiple mounts are to the same share from the same client it was not
possible to determine which section of /proc/fs/cifs/Stats (and DebugData)
correspond to that mount. In some recent examples this turned out to be
a significant problem when trying to analyze performance data - since
there are many cases where unless we know the tree id and session id we
can't figure out which stats (e.g. number of SMB3.1.1 requests by type,
the total time they take, which is slowest, how many fail etc.) apply to
which mount. The only existing loosely related ioctl CIFS_IOC_GET_MNT_INFO
does not return the information needed to uniquely identify which tcon
is which mount although it does return various flags and device info.

Add a cifs.ko ioctl CIFS_IOC_GET_TCON_INFO (0x800ccf0c) to return tid,
session id, tree connect count.

Cc: stable@vger.kernel.org
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: add missing return value check for cifs_sb_tlink

Whenever a tlink is obtained by cifs_sb_tlink, we need
to check that the tlink returned is not an error.
It was missing with the last change here.

Fixes: b3edef6b9cd0 ("cifs: allow dumping keys for directories too")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: allow dumping keys for directories too

Dumping the enc/dec keys is a session wide operation.
And it should not matter if the ioctl was run on
a regular file or a directory.

Currently, we obtain the tcon pointer from the
cifs file handle. But since there's no dir open call
in cifs, this is not populated for dirs.

This change allows dumping of session keys using ioctl
even for directories. To do this, we'll now get the
tcon pointer from the superblock, and not from the file
handle.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

cifs: address unused variable warning

Fix trivial unused variable warning (when SMB1 support disabled)

"ioctl.c:324:17: warning: variable 'caps' set but not used [-Wunused-but-set-variable]"

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202305250056.oZhsJmdD-lkp@intel.com/
Signed-off-by: Steve French <stfrench@microsoft.com>

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>