Commit Graph

10 Commits

Author SHA1 Message Date
Bharath SM
83898e4a85 smb: invalidate and close cached directory when creating child entries
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: 037e1bae58 ("smb: client: use ParentLeaseKey in cifs_do_create")

Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-07-13 17:16:29 -05:00
Henrique Carvalho
037e1bae58 smb: client: use ParentLeaseKey in cifs_do_create
Implement ParentLeaseKey logic in cifs_do_create() by looking up the
parent cfid, copying its lease key into the fid struct, and setting
the appropriate lease flag.

Fixes: f047390a09 ("CIFS: Add create lease v2 context for SMB3")
Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-06-01 20:46:45 -05:00
Linus Torvalds
d3d90cc289 Provide stable parent and name to ->d_revalidate() instances
Most of the filesystem methods where we care about dentry name
 and parent have their stability guaranteed by the callers;
 ->d_revalidate() is the major exception.
 
 It's easy enough for callers to supply stable values for
 expected name and expected parent of the dentry being
 validated.  That kills quite a bit of boilerplate in
 ->d_revalidate() instances, along with a bunch of races
 where they used to access ->d_name without sufficient
 precautions.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs d_revalidate updates from Al Viro:
 "Provide stable parent and name to ->d_revalidate() instances

  Most of the filesystem methods where we care about dentry name and
  parent have their stability guaranteed by the callers;
  ->d_revalidate() is the major exception.

  It's easy enough for callers to supply stable values for expected name
  and expected parent of the dentry being validated. That kills quite a
  bit of boilerplate in ->d_revalidate() instances, along with a bunch
  of races where they used to access ->d_name without sufficient
  precautions"

* tag 'pull-revalidate' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  9p: fix ->rename_sem exclusion
  orangefs_d_revalidate(): use stable parent inode and name passed by caller
  ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller
  nfs: fix ->d_revalidate() UAF on ->d_name accesses
  nfs{,4}_lookup_validate(): use stable parent inode passed by caller
  gfs2_drevalidate(): use stable parent inode and name passed by caller
  fuse_dentry_revalidate(): use stable parent inode and name passed by caller
  vfat_revalidate{,_ci}(): use stable parent inode passed by caller
  exfat_d_revalidate(): use stable parent inode passed by caller
  fscrypt_d_revalidate(): use stable parent inode passed by caller
  ceph_d_revalidate(): propagate stable name down into request encoding
  ceph_d_revalidate(): use stable parent inode passed by caller
  afs_d_revalidate(): use stable name and parent inode passed by caller
  Pass parent directory inode and expected name to ->d_revalidate()
  generic_ci_d_compare(): use shortname_storage
  ext4 fast_commit: make use of name_snapshot primitives
  dissolve external_name.u into separate members
  make take_dentry_name_snapshot() lockless
  dcache: back inline names with a struct-wrapped array of unsigned long
  make sure that DNAME_INLINE_LEN is a multiple of word size
2025-01-30 09:13:35 -08:00
Al Viro
5be1fa8abd Pass parent directory inode and expected name to ->d_revalidate()
->d_revalidate() often needs to access dentry parent and name; that has
to be done carefully, since the locking environment varies from caller
to caller.  We are not guaranteed that dentry in question will not be
moved right under us - not unless the filesystem is such that nothing
on it ever gets renamed.

It can be dealt with, but that results in boilerplate code that isn't
even needed - the callers normally have just found the dentry via dcache
lookup and want to verify that it's in the right place; they already
have the values of ->d_parent and ->d_name stable.  There is a couple
of exceptions (overlayfs and, to less extent, ecryptfs), but for the
majority of calls that song and dance is not needed at all.

It's easier to make ecryptfs and overlayfs find and pass those values if
there's a ->d_revalidate() instance to be called, rather than doing that
in the instances.

This commit only changes the calling conventions; making use of supplied
values is left to followups.

NOTE: some instances need more than just the parent - things like CIFS
may need to build an entire path from filesystem root, so they need
more precautions than the usual boilerplate.  This series doesn't
do anything to that need - these filesystems have to keep their locking
mechanisms (rename_lock loops, use of dentry_path_raw(), private rwsem
a-la v9fs).

One thing to keep in mind when using name is that name->name will normally
point into the pathname being resolved; the filename in question occupies
name->len bytes starting at name->name, and there is NUL somewhere after it,
but it the next byte might very well be '/' rather than '\0'.  Do not
ignore name->len.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-01-27 19:25:23 -05:00
Ruben Devos
11f8b80ab9 smb: client: fix order of arguments of tracepoints
The tracepoints based on smb3_inf_compound_*_class have tcon id and
session id swapped around. This results in incorrect output in
`trace-cmd report`.

Fix the order of arguments to resolve this issue. The trace-cmd output
below shows the before and after of the smb3_delete_enter and
smb3_delete_done events as an example. The smb3_cmd_* events show the
correct session and tcon id for reference.

Also fix tracepoint set -> get in the SMB2_OP_GET_REPARSE case.

BEFORE:
rm-2211  [001] .....  1839.550888: smb3_delete_enter:    xid=281 sid=0x5 tid=0x3d path=\hello2.txt
rm-2211  [001] .....  1839.550894: smb3_cmd_enter:        sid=0x1ac000000003d tid=0x5 cmd=5 mid=61
rm-2211  [001] .....  1839.550896: smb3_cmd_enter:        sid=0x1ac000000003d tid=0x5 cmd=6 mid=62
rm-2211  [001] .....  1839.552091: smb3_cmd_done:         sid=0x1ac000000003d tid=0x5 cmd=5 mid=61
rm-2211  [001] .....  1839.552093: smb3_cmd_done:         sid=0x1ac000000003d tid=0x5 cmd=6 mid=62
rm-2211  [001] .....  1839.552103: smb3_delete_done:     xid=281 sid=0x5 tid=0x3d

AFTER:
rm-2501  [001] .....  3237.656110: smb3_delete_enter:    xid=88 sid=0x1ac0000000041 tid=0x5 path=\hello2.txt
rm-2501  [001] .....  3237.656122: smb3_cmd_enter:        sid=0x1ac0000000041 tid=0x5 cmd=5 mid=84
rm-2501  [001] .....  3237.656123: smb3_cmd_enter:        sid=0x1ac0000000041 tid=0x5 cmd=6 mid=85
rm-2501  [001] .....  3237.657909: smb3_cmd_done:         sid=0x1ac0000000041 tid=0x5 cmd=5 mid=84
rm-2501  [001] .....  3237.657909: smb3_cmd_done:         sid=0x1ac0000000041 tid=0x5 cmd=6 mid=85
rm-2501  [001] .....  3237.657922: smb3_delete_done:     xid=88 sid=0x1ac0000000041 tid=0x5

Cc: stable@vger.kernel.org
Signed-off-by: Ruben Devos <devosruben6@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-01-19 19:34:00 -06:00
David Howells
e9e62243a3 cifs: Fix caching to try to do open O_WRONLY as rdwr on server
When we're engaged in local caching of a cifs filesystem, we cannot perform
caching of a partially written cache granule unless we can read the rest of
the granule.  This can result in unexpected access errors being reported to
the user.

Fix this by the following: if a file is opened O_WRONLY locally, but the
mount was given the "-o fsc" flag, try first opening the remote file with
GENERIC_READ|GENERIC_WRITE and if that returns -EACCES, try dropping the
GENERIC_READ and doing the open again.  If that last succeeds, invalidate
the cache for that file as for O_DIRECT.

Fixes: 70431bfd82 ("cifs: Support fscache indexing rewrite")
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-02 09:29:55 -05:00
Steve French
e9e9fbeb83 smb3: add trace event for mknod
Add trace points to help debug mknod and mkfifo:

   smb3_mknod_done
   smb3_mknod_enter
   smb3_mknod_err

Example output:

      TASK-PID     CPU#  |||||  TIMESTAMP  FUNCTION
         | |         |   |||||     |         |
    mkfifo-6163    [003] .....   960.425558: smb3_mknod_enter: xid=12 sid=0xb55130f6 tid=0x46e6241c path=\fifo1
    mkfifo-6163    [003] .....   960.432719: smb3_mknod_done: xid=12 sid=0xb55130f6 tid=0x46e6241c

Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Reviewed-by: Meetakshi Setiya <msetiya@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-03-26 14:56:36 -05:00
Paulo Alcantara
102466f303 smb: client: allow creating special files via reparse points
Add support for creating special files (e.g. char/block devices,
sockets, fifos) via NFS reparse points on SMB2+, which are fully
supported by most SMB servers and documented in MS-FSCC.

smb2_get_reparse_inode() creates the file with a corresponding reparse
point buffer set in @iov through a single roundtrip to the server.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202311260746.HOJ039BV-lkp@intel.com/
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-07 15:46:05 -06:00
Paulo Alcantara
0a049935e4 smb: client: get rid of dfs naming in automount code
Automount code will handle both DFS links and reparse mount points.

Also, get rid of BUG_ON() in cifs_release_automount_timer() while
we're at it.

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
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