Some servers (including Samba), support the SMB3.1.1 POSIX Extensions (which use reparse
points for handling special files) but do not properly advertise file system attribute
FILE_SUPPORTS_REPARSE_POINTS.  Although we don't check for this attribute flag when
querying special file information, we do check it when creating special files which
causes them to fail unnecessarily.   If we have negotiated SMB3.1.1 POSIX Extensions
with the server we can expect the server to support creating special files via
reparse points, and even if the server fails the operation due to really forbidding
creating special files, then it should be no problem and is more likely to return a
more accurate rc in any case (e.g. EACCES instead of EOPNOTSUPP).

Allow creating special files as long as the server supports either reparse points
or the SMB3.1.1 POSIX Extensions (note that if the "sfu" mount option is specified
it uses a different way of storing special files that does not rely on reparse points).

Cc: <stable@vger.kernel.org>
Fixes: 6c06be908ca19 ("cifs: Check if server supports reparse points before using them")
Acked-by: Ralph Boehme <slow@samba.org>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

When a parent lease key is passed to the server during a create operation
while holding a directory lease, the server may not send a lease break to
the client. In such cases, it becomes the client’s responsibility to
ensure cache consistency.

This led to a problem where directory listings (e.g., `ls` or `readdir`)
could return stale results after a new file is created.
eg:
ls /mnt/share/
touch /mnt/share/file1
ls /mnt/share/

In this scenario, the final `ls` may not show  `file1` due to the stale
directory cache.

For now, fix this by marking the cached directory as invalid if using
the parent lease key during create, and explicitly closing the cached
directory after successful file creation.

Fixes: 037e1bae588eacf ("smb: client: use ParentLeaseKey in cifs_do_create")

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

The CVE-2024-50047 fix removed asynchronous crypto handling from
crypt_message(), assuming all crypto operations are synchronous.
However, when hardware crypto accelerators are used, this can cause
use-after-free crashes:

  crypt_message()
    // Allocate the creq buffer containing the req
    creq = smb2_get_aead_req(..., &req);

    // Async encryption returns -EINPROGRESS immediately
    rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);

    // Free creq while async operation is still in progress
    kvfree_sensitive(creq, ...);

Hardware crypto modules often implement async AEAD operations for
performance. When crypto_aead_encrypt/decrypt() returns -EINPROGRESS,
the operation completes asynchronously. Without crypto_wait_req(),
the function immediately frees the request buffer, leading to crashes
when the driver later accesses the freed memory.

This results in a use-after-free condition when the hardware crypto
driver later accesses the freed request structure, leading to kernel
crashes with NULL pointer dereferences.

The issue occurs because crypto_alloc_aead() with mask=0 doesn't
guarantee synchronous operation. Even without CRYPTO_ALG_ASYNC in
the mask, async implementations can be selected.

Fix by restoring the async crypto handling:
- DECLARE_CRYPTO_WAIT(wait) for completion tracking
- aead_request_set_callback() for async completion notification
- crypto_wait_req() to wait for operation completion

This ensures the request buffer isn't freed until the crypto operation
completes, whether synchronous or asynchronous, while preserving the
CVE-2024-50047 fix.

Fixes: b0abcd65ec54 ("smb: client: fix UAF in async decryption")
Link: https://lore.kernel.org/all/8b784a13-87b0-4131-9ff9-7a8993538749@huaweicloud.com/
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Wang Zhaolong <wangzhaolong@huaweicloud.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

A race condition can occur in cifs_oplock_break() leading to a
use-after-free of the cinode structure when unmounting:

  cifs_oplock_break()
    _cifsFileInfo_put(cfile)
      cifsFileInfo_put_final()
        cifs_sb_deactive()
          [last ref, start releasing sb]
            kill_sb()
              kill_anon_super()
                generic_shutdown_super()
                  evict_inodes()
                    dispose_list()
                      evict()
                        destroy_inode()
                          call_rcu(&inode->i_rcu, i_callback)
    spin_lock(&cinode->open_file_lock)  <- OK
                            [later] i_callback()
                              cifs_free_inode()
                                kmem_cache_free(cinode)
    spin_unlock(&cinode->open_file_lock)  <- UAF
    cifs_done_oplock_break(cinode)       <- UAF

The issue occurs when umount has already released its reference to the
superblock. When _cifsFileInfo_put() calls cifs_sb_deactive(), this
releases the last reference, triggering the immediate cleanup of all
inodes under RCU. However, cifs_oplock_break() continues to access the
cinode after this point, resulting in use-after-free.

Fix this by holding an extra reference to the superblock during the
entire oplock break operation. This ensures that the superblock and
its inodes remain valid until the oplock break completes.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=220309
Fixes: b98749cac4a6 ("CIFS: keep FileInfo handle live during oplock break")
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Wang Zhaolong <wangzhaolong@huaweicloud.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

If ksmbd_iov_pin_rsp return error, use-after-free can happen by
accessing opinfo->state and opinfo_put and ksmbd_fd_put could
called twice.

Reported-by: Ziyan Xu <research@securitygossip.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

If the call of ksmbd_vfs_lock_parent() fails, we drop the parent_path
references and return an error.  We need to drop the write access we
just got on parent_path->mnt before we drop the mount reference - callers
assume that ksmbd_vfs_kern_path_locked() returns with mount write
access grabbed if and only if it has returned 0.

Fixes: 864fb5d37163 ("ksmbd: fix possible deadlock in smb2_open")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

The qp is created by rdma_create_qp() as t->cm_id->qp
and t->qp is just a shortcut.

rdma_destroy_qp() also calls ib_destroy_qp(cm_id->qp) internally,
but it is protected by a mutex, clears the cm_id and also calls
trace_cm_qp_destroy().

This should make the tracing more useful as both
rdma_create_qp() and rdma_destroy_qp() are traces and it makes
the code look more sane as functions from the same layer are used
for the specific qp object.

trace-cmd stream -e rdma_cma:cm_qp_create -e rdma_cma:cm_qp_destroy
shows this now while doing a mount and unmount from a client:

  <...>-80   [002] 378.514182: cm_qp_create:  cm.id=1 src=172.31.9.167:5445 dst=172.31.9.166:37113 tos=0 pd.id=0 qp_type=RC send_wr=867 recv_wr=255 qp_num=1 rc=0
  <...>-6283 [001] 381.686172: cm_qp_destroy: cm.id=1 src=172.31.9.167:5445 dst=172.31.9.166:37113 tos=0 qp_num=1

Before we only saw the first line.

Cc: Namjae Jeon <linkinjeon@kernel.org>
Cc: Steve French <stfrench@microsoft.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Hyunchul Lee <hyc.lee@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: linux-cifs@vger.kernel.org
Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers")
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

Pull smb client fixes from Steve French:

 - Two reconnect fixes including one for a reboot/reconnect race

 - Fix for incorrect file type that can be returned by SMB3.1.1 POSIX
   extensions

 - tcon initialization fix

 - Fix for resolving Windows symlinks with absolute paths

* tag 'v6.16-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: fix native SMB symlink traversal
  smb: client: fix race condition in negotiate timeout by using more precise timing
  cifs: all initializations for tcon should happen in tcon_info_alloc
  smb: client: fix warning when reconnecting channel
  smb: client: fix readdir returning wrong type with POSIX extensions

Pull vfs fixes from Christian Brauner:

 - Fix a regression caused by the anonymous inode rework. Making them
   regular files causes various places in the kernel to tip over
   starting with io_uring.

   Revert to the former status quo and port our assertion to be based on
   checking the inode so we don't lose the valuable VFS_*_ON_*()
   assertions that have already helped discover weird behavior our
   outright bugs.

 - Fix the the upper bound calculation in fuse_fill_write_pages()

 - Fix priority inversion issues in the eventpoll code

 - Make secretmen use anon_inode_make_secure_inode() to avoid bypassing
   the LSM layer

 - Fix a netfs hang due to missing case in final DIO read result
   collection

 - Fix a double put of the netfs_io_request struct

 - Provide some helpers to abstract out NETFS_RREQ_IN_PROGRESS flag
   wrangling

 - Fix infinite looping in netfs_wait_for_pause/request()

 - Fix a netfs ref leak on an extra subrequest inserted into a request's
   list of subreqs

 - Fix various cifs RPC callbacks to set NETFS_SREQ_NEED_RETRY if a
   subrequest fails retriably

 - Fix a cifs warning in the workqueue code when reconnecting a channel

 - Fix the updating of i_size in netfs to avoid a race between testing
   if we should have extended the file with a DIO write and changing
   i_size

 - Merge the places in netfs that update i_size on write

 - Fix coredump socket selftests

* tag 'vfs-6.16-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  anon_inode: rework assertions
  netfs: Update tracepoints in a number of ways
  netfs: Renumber the NETFS_RREQ_* flags to make traces easier to read
  netfs: Merge i_size update functions
  netfs: Fix i_size updating
  smb: client: set missing retry flag in cifs_writev_callback()
  smb: client: set missing retry flag in cifs_readv_callback()
  smb: client: set missing retry flag in smb2_writev_callback()
  netfs: Fix ref leak on inserted extra subreq in write retry
  netfs: Fix looping in wait functions
  netfs: Provide helpers to perform NETFS_RREQ_IN_PROGRESS flag wangling
  netfs: Fix double put of request
  netfs: Fix hang due to missing case in final DIO read result collection
  eventpoll: Fix priority inversion problem
  fuse: fix fuse_fill_write_pages() upper bound calculation
  fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass
  selftests/coredump: Fix "socket_detect_userspace_client" test failure

We've seen customers having shares mounted in paths like /??/C:/ or
/??/UNC/foo.example.com/share in order to get their native SMB
symlinks successfully followed from different mounts.

After commit 12b466eb52d9 ("cifs: Fix creating and resolving absolute NT-style symlinks"),
the client would then convert absolute paths from "/??/C:/" to "/mnt/c/"
by default.  The absolute paths would vary depending on the value of
symlinkroot= mount option.

Fix this by restoring old behavior of not trying to convert absolute
paths by default.  Only do this if symlinkroot= was _explicitly_ set.

Before patch:

  $ mount.cifs //w22-fs0/test2 /mnt/1 -o vers=3.1.1,username=xxx,password=yyy
  $ ls -l /mnt/1/symlink2
  lrwxr-xr-x 1 root root 15 Jun 20 14:22 /mnt/1/symlink2 -> /mnt/c/testfile
  $ mkdir -p /??/C:; echo foo > //??/C:/testfile
  $ cat /mnt/1/symlink2
  cat: /mnt/1/symlink2: No such file or directory

After patch:

  $ mount.cifs //w22-fs0/test2 /mnt/1 -o vers=3.1.1,username=xxx,password=yyy
  $ ls -l /mnt/1/symlink2
  lrwxr-xr-x 1 root root 15 Jun 20 14:22 /mnt/1/symlink2 -> '/??/C:/testfile'
  $ mkdir -p /??/C:; echo foo > //??/C:/testfile
  $ cat /mnt/1/symlink2
  foo

Cc: linux-cifs@vger.kernel.org
Reported-by: Pierguido Lambri <plambri@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Stefan Metzmacher <metze@samba.org>
Fixes: 12b466eb52d9 ("cifs: Fix creating and resolving absolute NT-style symlinks")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Steve French <stfrench@microsoft.com>