Commit Graph

4496 Commits

Author SHA1 Message Date
Steve French
d39fc592ef cifs: release leases for deferred close handles when freezing
We should not be caching closed files when freeze is invoked on an fs
(so we can release resources more gracefully).

Fixes xfstests generic/068 generic/390 generic/491

Reviewed-by: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-10 17:48:30 -05:00
Steve French
716a3cf317 smb3: fix problem remounting a share after shutdown
xfstests generic/392 showed a problem where even after a
shutdown call was made on a mount, we would still attempt
to use the (now inaccessible) superblock if another mount
was attempted for the same share.

Reported-by: David Howells <dhowells@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Fixes: 087f757b01 ("cifs: add shutdown support")
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-09 09:54:58 -05:00
Steve French
2cb6f96877 SMB3: force unmount was failing to close deferred close files
In investigating a failure with xfstest generic/392 it
was noticed that mounts were reusing a superblock that should
already have been freed. This turned out to be related to
deferred close files keeping a reference count until the
closetimeo expired.

Currently the only way an fs knows that mount is beginning is
when force unmount is called, but when this, ie umount_begin(),
is called all deferred close files on the share (tree
connection) should be closed immediately (unless shared by
another mount) to avoid using excess resources on the server
and to avoid reusing a superblock which should already be freed.

In umount_begin, close all deferred close handles for that
share if this is the last mount using that share on this
client (ie send the SMB3 close request over the wire for those
that have been already closed by the app but that we have
kept a handle lease open for and have not sent closes to the
server for yet).

Reported-by: David Howells <dhowells@redhat.com>
Acked-by: Bharath SM <bharathsm@microsoft.com>
Cc: <stable@vger.kernel.org>
Fixes: 78c09634f7 ("Cifs: Fix kernel oops caused by deferred close for files.")
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-09 09:53:59 -05:00
Steve French
ba8c2b75b0 smb3: improve parallel reads of large files
rasize (ra_pages) should be set higher than read size by default
to allow parallel reads when reading large files in order to
improve performance (otherwise there is much dead time on the
network when doing readahead of large files).  Default rasize
to twice readsize.

Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-09 00:59:48 -05:00
Steve French
cbd4cbabef do not reuse connection if share marked as isolated
"SHAREFLAG_ISOLATED_TRANSPORT" indicates that we should not reuse the socket
for this share (for future mounts).  Mark the socket as server->nosharesock if
share flags returned include SHAREFLAG_ISOLATED_TRANSPORT.

See MS-SMB2 MS-SMB2 2.2.10 and 3.2.5.5

Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-08 12:00:47 -05:00
Pawel Witek
d66cde50c3 cifs: fix pcchunk length type in smb2_copychunk_range
Change type of pcchunk->Length from u32 to u64 to match
smb2_copychunk_range arguments type. Fixes the problem where performing
server-side copy with CIFS_IOC_COPYCHUNK_FILE ioctl resulted in incomplete
copy of large files while returning -EINVAL.

Fixes: 9bf0c9cd43 ("CIFS: Fix SMB2/SMB3 Copy offload support (refcopy) for large files")
Cc: <stable@vger.kernel.org>
Signed-off-by: Pawel Witek <pawel.ireneusz.witek@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-08 12:00:47 -05:00
Yang Li
9ee04875ae cifs: Remove unneeded semicolon
./fs/cifs/smb2pdu.c:4140:2-3: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=4863
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-05 04:29:58 -05:00
Paulo Alcantara
8e3554150d cifs: fix sharing of DFS connections
When matching DFS connections, we can't rely on the values set in
cifs_sb_info::prepath and cifs_tcon::tree_name as they might change
during DFS failover.  The DFS referrals related to a specific DFS tcon
are already matched earlier in match_server(), therefore we can safely
skip those checks altogether as the connection is guaranteed to be
unique for the DFS tcon.

Besides, when creating or finding an SMB session, make sure to also
refcount any DFS root session related to it (cifs_ses::dfs_root_ses),
so if a new DFS mount ends up reusing the connection from the old
mount while there was an umount(2) still in progress (e.g. umount(2)
-> cifs_umount() -> reconnect -> cifs_put_tcon()), the connection
could potentially be put right after the umount(2) finished.

Patch has minor update to include fix for unused variable issue
noted by the kernel test robot

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202305041040.j7W2xQSy-lkp@intel.com/
Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-04 16:54:44 -05:00
Paulo Alcantara
6be2ea33a4 cifs: avoid potential races when handling multiple dfs tcons
Now that a DFS tcon manages its own list of DFS referrals and
sessions, there is no point in having a single worker to refresh
referrals of all DFS tcons.  Make it faster and less prone to race
conditions when having several mounts by queueing a worker per DFS
tcon that will take care of refreshing only the DFS referrals related
to it.

Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-03 23:29:47 -05:00
Paulo Alcantara
3dc9c433c9 cifs: protect access of TCP_Server_Info::{origin,leaf}_fullpath
Protect access of TCP_Server_Info::{origin,leaf}_fullpath when
matching DFS connections, and get rid of
TCP_Server_Info::current_fullpath while we're at it.

Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-03 23:29:39 -05:00
Paulo Alcantara
ee20d7c610 cifs: fix potential race when tree connecting ipc
Protect access of TCP_Server_Info::hostname when building the ipc tree
name as it might get freed in cifsd thread and thus causing an
use-after-free bug in __tree_connect_dfs_target().  Also, while at it,
update status of IPC tcon on success and then avoid any extra tree
connects.

Cc: stable@vger.kernel.org # v6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-03 23:29:05 -05:00
Paulo Alcantara
90c49fce1c cifs: fix potential use-after-free bugs in TCP_Server_Info::hostname
TCP_Server_Info::hostname may be updated once or many times during
reconnect, so protect its access outside reconnect path as well and
then prevent any potential use-after-free bugs.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-02 09:41:09 -05:00
Paulo Alcantara
1810769e3a cifs: print smb3_fs_context::source when mounting
Print full device name (UNC + optional prefix) from @old_ctx->source
when printing info about mount.

Before patch

  mount.cifs //srv/share/dir /mnt -o ...
  dmesg
  ...
  CIFS: Attempting to mount \\srv\share

After patch

  mount.cifs //srv/share/dir /mnt -o ...
  dmesg
  ...
  CIFS: Attempting to mount //srv/share/dir

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-02 09:23:51 -05:00
Paulo Alcantara
5bff9f741a cifs: protect session status check in smb2_reconnect()
Use @ses->ses_lock to protect access of @ses->ses_status.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-02 09:23:51 -05:00
Linus Torvalds
26c009dffc 11 smb3 client fixes, mostly cleanup
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Merge tag '6.4-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:

 - deferred close fix for an important case when cached file should be
   closed immediately

 - two fixes for missing locks

 - eight minor cleanup

* tag '6.4-rc-smb3-client-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: update internal module version number for cifs.ko
  smb3: move some common open context structs to smbfs_common
  smb3: make query_on_disk_id open context consistent and move to common code
  SMB3.1.1: add new tree connect ShareFlags
  cifs: missing lock when updating session status
  SMB3: Close deferred file handles in case of handle lease break
  SMB3: Add missing locks to protect deferred close file list
  cifs: Avoid a cast in add_lease_context()
  cifs: Simplify SMB2_open_init()
  cifs: Simplify SMB2_open_init()
  cifs: Simplify SMB2_open_init()
2023-05-01 10:43:44 -07:00
Steve French
9be11a6931 cifs: update internal module version number for cifs.ko
From 2.42 to 2.43

Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-28 22:50:42 -05:00
Steve French
2fe187dca6 smb3: move some common open context structs to smbfs_common
create durable and create durable reconnect context and the maximal
access create context struct definitions can be put in common code in
smbfs_common

Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-28 22:50:32 -05:00
Steve French
1149c8467d smb3: make query_on_disk_id open context consistent and move to common code
cifs and ksmbd were using a slightly different version of the query_on_disk_id
struct which could be confusing. Use the ksmbd version of this struct, and
move it to common code.

Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-28 22:50:16 -05:00
Steve French
943fb67b09 cifs: missing lock when updating session status
Coverity noted a place where we were not grabbing
the ses_lock when setting (and checking) ses_status.

Addresses-Coverity: 1536833 ("Data race condition (MISSING_LOCK)")
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-28 21:23:42 -05:00
Bharath SM
d906be3fa5 SMB3: Close deferred file handles in case of handle lease break
We should not cache deferred file handles if we dont have
handle lease on a file. And we should immediately close all
deferred handles in case of handle lease break.

Fixes: 9e31678fb4 ("SMB3: fix lease break timeout when multiple deferred close handles for the same file.")
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-27 11:03:33 -05:00
Bharath SM
ab9ddc87a9 SMB3: Add missing locks to protect deferred close file list
cifs_del_deferred_close function has a critical section which modifies
the deferred close file list. We must acquire deferred_lock before
calling cifs_del_deferred_close function.

Fixes: ca08d0eac0 ("cifs: Fix memory leak on the deferred close")
Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Acked-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-27 11:00:10 -05:00
Linus Torvalds
7bcff5a396 v6.4/vfs.acl
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Merge tag 'v6.4/vfs.acl' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull acl updates from Christian Brauner:
 "After finishing the introduction of the new posix acl api last cycle
  the generic POSIX ACL xattr handlers are still around in the
  filesystems xattr handlers for two reasons:

   (1) Because a few filesystems rely on the ->list() method of the
       generic POSIX ACL xattr handlers in their ->listxattr() inode
       operation.

   (2) POSIX ACLs are only available if IOP_XATTR is raised. The
       IOP_XATTR flag is raised in inode_init_always() based on whether
       the sb->s_xattr pointer is non-NULL. IOW, the registered xattr
       handlers of the filesystem are used to raise IOP_XATTR. Removing
       the generic POSIX ACL xattr handlers from all filesystems would
       risk regressing filesystems that only implement POSIX ACL support
       and no other xattrs (nfs3 comes to mind).

  This contains the work to decouple POSIX ACLs from the IOP_XATTR flag
  as they don't depend on xattr handlers anymore. So it's now possible
  to remove the generic POSIX ACL xattr handlers from the sb->s_xattr
  list of all filesystems. This is a crucial step as the generic POSIX
  ACL xattr handlers aren't used for POSIX ACLs anymore and POSIX ACLs
  don't depend on the xattr infrastructure anymore.

  Adressing problem (1) will require more long-term work. It would be
  best to get rid of the ->list() method of xattr handlers completely at
  some point.

  For erofs, ext{2,4}, f2fs, jffs2, ocfs2, and reiserfs the nop POSIX
  ACL xattr handler is kept around so they can continue to use
  array-based xattr handler indexing.

  This update does simplify the ->listxattr() implementation of all
  these filesystems however"

* tag 'v6.4/vfs.acl' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  acl: don't depend on IOP_XATTR
  ovl: check for ->listxattr() support
  reiserfs: rework priv inode handling
  fs: rename generic posix acl handlers
  reiserfs: rework ->listxattr() implementation
  fs: simplify ->listxattr() implementation
  fs: drop unused posix acl handlers
  xattr: remove unused argument
  xattr: add listxattr helper
  xattr: simplify listxattr helpers
2023-04-24 13:35:23 -07:00
Volker Lendecke
919e57c314 cifs: Avoid a cast in add_lease_context()
We have the correctly-typed struct smb2_create_req * available in the
caller.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by Ralph Boehme <slow@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-23 21:16:57 -05:00
Volker Lendecke
d2ec43b515 cifs: Simplify SMB2_open_init()
Reduce code duplication by calculating req->CreateContextsLength in
one place.

This is the last reference to "req" in the add_*_context functions,
remove that parameter.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-23 20:31:44 -05:00
Volker Lendecke
2a8d1387ed cifs: Simplify SMB2_open_init()
Reduce code duplication by stitching together create contexts in one
place.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-23 20:31:44 -05:00
Volker Lendecke
5ec629e037 cifs: Simplify SMB2_open_init()
We can point to the create contexts in just one place, we don't have
to do this in every add_*_context routine.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-23 20:31:44 -05:00
David Howells
023fc150a3 cifs: Reapply lost fix from commit 30b2b2196d
Reapply the fix from:

   30b2b2196d ("cifs: do not include page data when checking signature")

that got lost in the iteratorisation of the cifs driver.

Fixes: d08089f649 ("cifs: Change the I/O paths to use an iterator rather than a page list")
Acked-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reported-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Paulo Alcantara <pc@cjr.nz>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Bharath S M <bharathsm@microsoft.com>
cc: Enzo Matsumiya <ematsumiya@suse.de>
cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-18 21:26:09 -05:00
David Howells
ac13692844 cifs: Fix unbuffered read
If read() is done in an unbuffered manner, such that, say,
cifs_strict_readv() goes through cifs_user_readv() and thence
__cifs_readv(), it doesn't recognise the EOF and keeps indicating to
userspace that it returning full buffers of data.

This is due to ctx->iter being advanced in cifs_send_async_read() as the
buffer is split up amongst a number of rdata objects.  The iterator count
is then used in collect_uncached_read_data() in the non-DIO case to set the
total length read - and thus the return value of sys_read().  But since the
iterator normally gets used up completely during splitting, ctx->total_len
gets overridden to the full amount.

However, prior to that in collect_uncached_read_data(), we've gone through
the list of rdatas and added up the amount of data we actually received
(which we then throw away).

Fix this by removing the bit that overrides the amount read in the non-DIO
case and just going with the total added up in the aforementioned loop.

This was observed by mounting a cifs share with multiple channels, e.g.:

	mount //192.168.6.1/test /test/ -o user=shares,pass=...,max_channels=6

and then reading a 1MiB file on the share:

	strace cat /xfstest.test/1M  >/dev/null

Through strace, the same data can be seen being read again and again.

Fixes: d08089f649 ("cifs: Change the I/O paths to use an iterator rather than a page list")
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
cc: Jérôme Glisse <jglisse@redhat.com>
cc: Long Li <longli@microsoft.com>
cc: Enzo Matsumiya <ematsumiya@suse.de>
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
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-18 21:22:08 -05:00
Paulo Alcantara
d5a863a153 cifs: avoid dup prefix path in dfs_get_automount_devname()
@server->origin_fullpath already contains the tree name + optional
prefix, so avoid calling __build_path_from_dentry_optional_prefix() as
it might end up duplicating prefix path from @cifs_sb->prepath into
final full path.

Instead, generate DFS full path by simply merging
@server->origin_fullpath with dentry's path.

This fixes the following case

	mount.cifs //root/dfs/dir /mnt/ -o ...
	ls /mnt/link

where cifs_dfs_do_automount() will call smb3_parse_devname() with
@devname set to "//root/dfs/dir/link" instead of
"//root/dfs/dir/dir/link".

Fixes: 7ad54b98fc ("cifs: use origin fullpath for automounts")
Cc: <stable@vger.kernel.org> # 6.2+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-16 18:04:36 -05:00
David Disseldorp
5105a7ffce cifs: fix negotiate context parsing
smb311_decode_neg_context() doesn't properly check against SMB packet
boundaries prior to accessing individual negotiate context entries. This
is due to the length check omitting the eight byte smb2_neg_context
header, as well as incorrect decrementing of len_of_ctxts.

Fixes: 5100d8a3fe ("SMB311: Improve checking of negotiate security contexts")
Reported-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-15 18:26:56 -05:00
Dan Carpenter
4f5d5b33fc cifs: double lock in cifs_reconnect_tcon()
This lock was supposed to be an unlock.

Fixes: 6cc041e90c ("cifs: avoid races in parallel reconnects in smb1")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-06 22:45:41 -05:00
Thiago Rafael Becker
d19342c660 cifs: sanitize paths in cifs_update_super_prepath.
After a server reboot, clients are failing to move files with ENOENT.
This is caused by DFS referrals containing multiple separators, which
the server move call doesn't recognize.

v1: Initial patch.
v2: Move prototype to header.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=2182472
Fixes: a31080899d ("cifs: sanitize multiple delimiters in prepath")
Actually-Fixes: 24e0a1eff9 ("cifs: switch to new mount api")
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Thiago Rafael Becker <tbecker@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-04-05 12:32:19 -05:00
Paulo Alcantara
e036771007 cifs: get rid of dead check in smb2_reconnect()
The SMB2_IOCTL check in the switch statement will never be true as we
return earlier from smb2_reconnect() if @smb2_command == SMB2_IOCTL.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-30 17:56:30 -05:00
Paulo Alcantara
09ba47b44d cifs: prevent infinite recursion in CIFSGetDFSRefer()
We can't call smb_init() in CIFSGetDFSRefer() as cifs_reconnect_tcon()
may end up calling CIFSGetDFSRefer() again to get new DFS referrals
and thus causing an infinite recursion.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-30 17:56:27 -05:00
Paulo Alcantara
6cc041e90c cifs: avoid races in parallel reconnects in smb1
Prevent multiple threads of doing negotiate, session setup and tree
connect by holding @ses->session_mutex in cifs_reconnect_tcon() while
reconnecting session and tcon.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-30 17:55:55 -05:00
David Disseldorp
179a88a855 cifs: fix DFS traversal oops without CONFIG_CIFS_DFS_UPCALL
When compiled with CONFIG_CIFS_DFS_UPCALL disabled, cifs_dfs_d_automount
is NULL. cifs.ko logic for mapping CIFS_FATTR_DFS_REFERRAL attributes to
S_AUTOMOUNT and corresponding dentry flags is retained regardless of
CONFIG_CIFS_DFS_UPCALL, leading to a NULL pointer dereference in
VFS follow_automount() when traversing a DFS referral link:
  BUG: kernel NULL pointer dereference, address: 0000000000000000
  ...
  Call Trace:
   <TASK>
   __traverse_mounts+0xb5/0x220
   ? cifs_revalidate_mapping+0x65/0xc0 [cifs]
   step_into+0x195/0x610
   ? lookup_fast+0xe2/0xf0
   path_lookupat+0x64/0x140
   filename_lookup+0xc2/0x140
   ? __create_object+0x299/0x380
   ? kmem_cache_alloc+0x119/0x220
   ? user_path_at_empty+0x31/0x50
   user_path_at_empty+0x31/0x50
   __x64_sys_chdir+0x2a/0xd0
   ? exit_to_user_mode_prepare+0xca/0x100
   do_syscall_64+0x42/0x90
   entry_SYSCALL_64_after_hwframe+0x72/0xdc

This fix adds an inline cifs_dfs_d_automount() {return -EREMOTE} handler
when CONFIG_CIFS_DFS_UPCALL is disabled. An alternative would be to
avoid flagging S_AUTOMOUNT, etc. without CONFIG_CIFS_DFS_UPCALL. This
approach was chosen as it provides more control over the error path.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-30 17:28:44 -05:00
Steve French
491eafce1a smb3: fix unusable share after force unmount failure
If user does forced unmount ("umount -f") while files are still open
on the share (as was seen in a Kubernetes example running on SMB3.1.1
mount) then we were marking the share as "TID_EXITING" in umount_begin()
which caused all subsequent operations (except write) to fail ... but
unfortunately when umount_begin() is called we do not know yet that
there are open files or active references on the share that would prevent
unmount from succeeding.  Kubernetes had example when they were doing
umount -f when files were open which caused the share to become
unusable until the files were closed (and the umount retried).

Fix this so that TID_EXITING is not set until we are about to send
the tree disconnect (not at the beginning of forced umounts in
umount_begin) so that if "umount -f" fails (due to open files or
references) the mount is still usable.

Cc: stable@vger.kernel.org
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 14:37:12 -05:00
Paulo Alcantara
be4fde7981 cifs: fix dentry lookups in directory handle cache
Get rid of any prefix paths in @path before lookup_positive_unlocked()
as it will call ->lookup() which already adds those prefix paths
through build_path_from_dentry().

This has caused a performance regression when mounting shares with a
prefix path where readdir(2) would end up retrying several times to
open bad directory names that contained duplicate prefix paths.

Fix this by skipping any prefix paths in @path before calling
lookup_positive_unlocked().

Fixes: e4029e0726 ("cifs: find and use the dentry for cached non-root directories also")
Cc: stable@vger.kernel.org # 6.1+
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 14:37:12 -05:00
Steve French
7e0e76d990 smb3: lower default deferred close timeout to address perf regression
Performance tests with large number of threads noted that the change
of the default closetimeo (deferred close timeout between when
close is done by application and when client has to send the close
to the server), to 5 seconds from 1 second, significantly degraded
perf in some cases like this (in the filebench example reported,
the stats show close requests on the wire taking twice as long,
and 50% regression in filebench perf). This is stil configurable
via mount parm closetimeo, but to be safe, decrease default back
to its previous value of 1 second.

Reported-by: Yin Fengwei <fengwei.yin@intel.com>
Reported-by: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/lkml/997614df-10d4-af53-9571-edec36b0e2f3@intel.com/
Fixes: 5efdd9122e ("smb3: allow deferred close timeout to be configurable")
Cc: stable@vger.kernel.org # 6.0+
Tested-by: Yin Fengwei <fengwei.yin@intel.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 14:37:12 -05:00
Paulo Alcantara
c24bb1a87d cifs: fix missing unload_nls() in smb2_reconnect()
Make sure to unload_nls() @nls_codepage if we no longer need it.

Fixes: bc962159e8 ("cifs: avoid race conditions with parallel reconnects")
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 14:37:05 -05:00
Shyam Prasad N
bc962159e8 cifs: avoid race conditions with parallel reconnects
When multiple processes/channels do reconnects in parallel
we used to return success immediately
negotiate/session-setup/tree-connect, causing race conditions
between processes that enter the function in parallel.
This caused several errors related to session not found to
show up during parallel reconnects.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 09:03:55 -05:00
Shyam Prasad N
fddc6ccc48 cifs: append path to open_enter trace event
We do not dump the file path for smb3_open_enter ftrace
calls, which is a severe handicap while debugging
using ftrace evens. This change adds that info.

Unfortunately, we're not updating the path in open params
in many places; which I had to do as a part of this change.
SMB2_open gets path in utf16 format, but it's easier of
path is supplied as char pointer in oparms.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-24 09:02:26 -05:00
Shyam Prasad N
175b54abc4 cifs: print session id while listing open files
In the output of /proc/fs/cifs/open_files, we only print
the tree id for the tcon of each open file. It becomes
difficult to know which tcon these files belong to with
just the tree id.

This change dumps ses id in addition to all other data today.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-23 11:19:42 -05:00
Shyam Prasad N
d12bc6d26f cifs: dump pending mids for all channels in DebugData
Currently, we only dump the pending mid information only
on the primary channel in /proc/fs/cifs/DebugData.
If multichannel is active, we do not print the pending MID
list on secondary channels.

This change will dump the pending mids for all the channels
based on server->conn_id.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-23 11:19:42 -05:00
Shyam Prasad N
896cd316b8 cifs: empty interface list when server doesn't support query interfaces
When querying server interfaces returns -EOPNOTSUPP,
clear the list of interfaces. Assumption is that multichannel
would be disabled too.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-23 11:19:42 -05:00
Shyam Prasad N
072a28c890 cifs: do not poll server interfaces too regularly
We have the server interface list hanging off the tcon
structure today for reasons unknown. So each tcon which is
connected to a file server can query them separately,
which is really unnecessary. To avoid this, in the query
function, we will check the time of last update of the
interface list, and avoid querying the server if it is
within a certain range.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-23 11:19:42 -05:00
Shyam Prasad N
2f4e429c84 cifs: lock chan_lock outside match_session
Coverity had rightly indicated a possible deadlock
due to chan_lock being done inside match_session.
All callers of match_* functions should pick up the
necessary locks and call them.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org
Fixes: 724244cdb3 ("cifs: protect session channel fields with chan_lock")
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-22 23:15:40 -05:00
Shyam Prasad N
2f0e4f0342 cifs: check only tcon status on tcon related functions
We had a couple of checks for session in cifs_tree_connect
and cifs_mark_open_files_invalid, which were unnecessary.
And that was done with ses_lock. Changed that to tc_lock too.

Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-17 13:22:22 -05:00
Paulo Alcantara
6284e46bdd cifs: use DFS root session instead of tcon ses
Use DFS root session whenever possible to get new DFS referrals
otherwise we might end up with an IPC tcon (tcon->ses->tcon_ipc) that
doesn't respond to them.  It should be safe accessing
@ses->dfs_root_ses directly in cifs_inval_name_dfs_link_error() as it
has same lifetime as of @tcon.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-14 22:48:53 -05:00
Paulo Alcantara
f446a63080 cifs: return DFS root session id in DebugData
Return the DFS root session id in /proc/fs/cifs/DebugData to make it
easier to track which IPC tcon was used to get new DFS referrals for a
specific connection, and aids in debugging.

A simple output of it would be

  Sessions:
  1) Address: 192.168.1.13 Uses: 1 Capability: 0x300067   Session Status: 1
  Security type: RawNTLMSSP  SessionId: 0xd80000000009
  User: 0 Cred User: 0
  DFS root session id: 0x128006c000035

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Cc: stable@vger.kernel.org # 6.2
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-03-14 21:43:23 -05:00