Clang static checker(scan-build) warning:
fs/stat.c:287:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
287 | stat->result_mask |= STATX_MNT_ID_UNIQUE;
| ~~~~~~~~~~~~~~~~~ ^
fs/stat.c:290:21: warning: The left expression of the compound assignment is
an uninitialized value. The computed value will also be garbage.
290 | stat->result_mask |= STATX_MNT_ID;
When vfs_getattr() failed because of security_inode_getattr(), 'stat' is
uninitialized. In this case, there is a harmless garbage problem in
vfs_statx_path(). It's better to return error directly when
vfs_getattr() failed, avoiding garbage value and more clearly.
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20250119025946.1168957-1-suhui@nfschina.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Previously, bch2_bkey_sectors_need_rebalance() called
bch2_target_accepts_data(), checking whether the target is writable.
However, this means that adding or removing devices from a target would
change the value of bch2_bkey_sectors_need_rebalance() for an existing
extent; this needs to be invariant so that the extent trigger can
correctly maintain rebalance_work accounting.
Instead, check target_accepts_data() in io_opts_to_rebalance_opts(),
before creating the bch_extent_rebalance entry.
This fixes (one?) cause of rebalance_work accounting being off.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
The discard path is supposed to issue journal flushes when there's too
many buckets empty buckets that need a journal commit before they can be
written to again, but at some point this code seems to have been lost.
Bring it back with a new optimization to make sure we don't issue too
many journal flushes: the journal now tracks the sequence number of the
most recent flush in progress, which the discard path uses when deciding
which buckets need a journal flush.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
In the previous commit b3d82c2f27, code was added to prevent journal sequence
overflow. Among them, the code added to journal_entry_open() uses the
bch2_fs_fatal_err_on() function to handle errors.
However, __journal_res_get() , which calls journal_entry_open() , calls
journal_entry_open() while holding journal->lock , but bch2_fs_fatal_err_on()
internally tries to acquire journal->lock , which results in a deadlock.
So we need to add a locked helper to handle fatal errors even when the
journal->lock is held.
Fixes: b3d82c2f27 ("bcachefs: Guard against journal seq overflow")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
For some unknown reason, checks on struct bkey_s_c_snapshot and struct
bkey_s_c_snapshot_tree pointers are missing.
Therefore, I think it would be appropriate to fix the incorrect pointer checking
through this patch.
Fixes: 4bd06f07bc ("bcachefs: Fixes for snapshot_tree.master_subvol")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
MS-SMB2 section 2.2.13.2.10 specifies that 'epoch' should be a 16-bit
unsigned integer used to track lease state changes. Change the data
type of all instances of 'epoch' from unsigned int to __u16. This
simplifies the epoch change comparisons and makes the code more
compliant with the protocol spec.
Cc: stable@vger.kernel.org
Signed-off-by: Meetakshi Setiya <msetiya@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
After commit 36008fe6e3 ("smb: client: don't try following DFS links
in cifs_tree_connect()"), TCP_Server_Info::leaf_fullpath will no
longer be changed, so there is no need to kstrdup() it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When the client attempts to tree connect to a domain-based DFS
namespace from a DFS interlink target, the server will return
STATUS_BAD_NETWORK_NAME and the following will appear on dmesg:
CIFS: VFS: BAD_NETWORK_NAME: \\dom\dfs
Since a DFS share might contain several DFS interlinks and they expire
after 10 minutes, the above message might end up being flooded on
dmesg when mounting or accessing them.
Print this only once per share.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Some servers don't respect the DFSREF_STORAGE_SERVER bit, so
unconditionally tree connect to DFS link target and then decide
whether or not continue chasing DFS referrals for DFS interlinks.
Otherwise the client would fail to mount such shares.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull btrfs fixes from David Sterba:
- add lockdep annotation for relocation root to fix a splat warning
while merging roots
- fix assertion failure when splitting ordered extent after transaction
abort
- don't print 'qgroup inconsistent' message when rescan process updates
qgroup data sooner than the subvolume deletion process
- fix use-after-free (accessing the error number) when attempting to
join an aborted transaction
- avoid starting new transaction if not necessary when cleaning qgroup
during subvolume drop
* tag 'for-6.14-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: avoid starting new transaction when cleaning qgroup during subvolume drop
btrfs: fix use-after-free when attempting to join an aborted transaction
btrfs: do not output error message if a qgroup has been already cleaned up
btrfs: fix assertion failure when splitting ordered extent after transaction abort
btrfs: fix lockdep splat while merging a relocation root
Pull d_revalidate fix from Al Viro:
"Fix a braino in d_revalidate series: check ->d_op for NULL"
* tag 'pull-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fix braino in "9p: fix ->rename_sem exclusion"
Pull xfs bug fixes from Carlos Maiolino:
"A few fixes for XFS, but the most notable one is:
- xfs: remove xfs_buf_cache.bc_lock
which has been hit by different persons including syzbot"
* tag 'xfs-fixes-6.14-rc2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: remove xfs_buf_cache.bc_lock
xfs: Add error handling for xfs_reflink_cancel_cow_range
xfs: Propagate errors from xfs_reflink_cancel_cow_range in xfs_dax_write_iomap_end
xfs: don't call remap_verify_area with sb write protection held
xfs: remove an out of data comment in _xfs_buf_alloc
xfs: fix the entry condition of exact EOF block allocation optimization
nfsd_file_dispose_list_delayed can be called from the filecache
laundrette, which is shut down after the nfsd threads are shut down and
the nfsd_serv pointer is cleared. If nn->nfsd_serv is NULL then there
are no threads to wake.
Ensure that the nn->nfsd_serv pointer is non-NULL before calling
svc_wake_up in nfsd_file_dispose_list_delayed. This is safe since the
svc_serv is not freed until after the filecache laundrette is cancelled.
Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Closes: https://bugs.debian.org/1093734
Fixes: ffb4025961 ("nfsd: Don't leave work of closing files to a work queue")
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Pull misc vfs cleanups from Al Viro:
"Two unrelated patches - one is a removal of long-obsolete include in
overlayfs (it used to need fs/internal.h, but the extern it wanted has
been moved back to include/linux/namei.h) and another introduces
convenience helper constructing struct qstr by a NUL-terminated
string"
* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
add a string-to-qstr constructor
fs/overlayfs/namei.c: get rid of include ../internal.h
Pull more smb client updates from Steve French:
- various updates for special file handling: symlink handling,
support for creating sockets, cleanups, new mount options (e.g. to
allow disabling using reparse points for them, and to allow
overriding the way symlinks are saved), and fixes to error paths
- fix for kerberos mounts (allow IAKerb)
- SMB1 fix for stat and for setting SACL (auditing)
- fix an incorrect error code mapping
- cleanups"
* tag 'v6.14-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6: (21 commits)
cifs: Fix parsing native symlinks directory/file type
cifs: update internal version number
cifs: Add support for creating WSL-style symlinks
smb3: add support for IAKerb
cifs: Fix struct FILE_ALL_INFO
cifs: Add support for creating NFS-style symlinks
cifs: Add support for creating native Windows sockets
cifs: Add mount option -o reparse=none
cifs: Add mount option -o symlink= for choosing symlink create type
cifs: Fix creating and resolving absolute NT-style symlinks
cifs: Simplify reparse point check in cifs_query_path_info() function
cifs: Remove symlink member from cifs_open_info_data union
cifs: Update description about ACL permissions
cifs: Rename struct reparse_posix_data to reparse_nfs_data_buffer and move to common/smb2pdu.h
cifs: Remove struct reparse_posix_data from struct cifs_open_info_data
cifs: Remove unicode parameter from parse_reparse_point() function
cifs: Fix getting and setting SACLs over SMB1
cifs: Remove intermediate object of failed create SFU call
cifs: Validate EAs for WSL reparse points
cifs: Change translation of STATUS_PRIVILEGE_NOT_HELD to -EPERM
...
Pull debugfs fix from Greg KH:
"Here is a single debugfs fix from Al to resolve a reported regression
in the driver-core tree. It has been reported to fix the issue"
* tag 'driver-core-6.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
debugfs: Fix the missing initializations in __debugfs_file_get()
Pull misc fixes from Andrew Morton:
"21 hotfixes. 8 are cc:stable and the remainder address post-6.13
issues. 13 are for MM and 8 are for non-MM.
All are singletons, please see the changelogs for details"
* tag 'mm-hotfixes-stable-2025-02-01-03-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (21 commits)
MAINTAINERS: include linux-mm for xarray maintenance
revert "xarray: port tests to kunit"
MAINTAINERS: add lib/test_xarray.c
mailmap, MAINTAINERS, docs: update Carlos's email address
mm/hugetlb: fix hugepage allocation for interleaved memory nodes
mm: gup: fix infinite loop within __get_longterm_locked
mm, swap: fix reclaim offset calculation error during allocation
.mailmap: update email address for Christopher Obbard
kfence: skip __GFP_THISNODE allocations on NUMA systems
nilfs2: fix possible int overflows in nilfs_fiemap()
mm: compaction: use the proper flag to determine watermarks
kernel: be more careful about dup_mmap() failures and uprobe registering
mm/fake-numa: handle cases with no SRAT info
mm: kmemleak: fix upper boundary check for physical address objects
mailmap: add an entry for Hamza Mahfooz
MAINTAINERS: mailmap: update Yosry Ahmed's email address
scripts/gdb: fix aarch64 userspace detection in get_current_task
mm/vmscan: accumulate nr_demoted for accurate demotion statistics
ocfs2: fix incorrect CPU endianness conversion causing mount failure
mm/zsmalloc: add __maybe_unused attribute for is_first_zpdesc()
...
Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result
by being prepared to go through potentially maxblocks == INT_MAX blocks,
the value in n may experience an overflow caused by left shift of blkbits.
While it is extremely unlikely to occur, play it safe and cast right hand
expression to wider type to mitigate the issue.
Found by Linux Verification Center (linuxtesting.org) with static analysis
tool SVACE.
Link: https://lkml.kernel.org/r/20250124222133.5323-1-konishi.ryusuke@gmail.com
Fixes: 622daaff0a ("nilfs2: fiemap support")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
As SMB protocol distinguish between symlink to directory and symlink to
file, add some mechanism to disallow resolving incompatible types.
When SMB symlink is of the directory type, ensure that its target path ends
with slash. This forces Linux to not allow resolving such symlink to file.
And when SMB symlink is of the file type and its target path ends with
slash then returns an error as such symlink is unresolvable. Such symlink
always points to invalid location as file cannot end with slash.
As POSIX server does not distinguish between symlinks to file and symlink
directory, do not apply this change for symlinks from POSIX SMB server. For
POSIX SMB servers, this change does nothing.
This mimics Windows behavior of native SMB symlinks.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This change implements support for creating new symlink in WSL-style by
Linux cifs client when -o reparse=wsl mount option is specified. WSL-style
symlink uses reparse point with tag IO_REPARSE_TAG_LX_SYMLINK and symlink
target location is stored in reparse buffer in UTF-8 encoding prefixed by
32-bit flags. Flags bits are unknown, but it was observed that WSL always
sets flags to value 0x02000000. Do same in Linux cifs client.
New symlinks would be created in WSL-style only in case the mount option
-o reparse=wsl is specified, which is not by default. So default CIFS
mounts are not affected by this change.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
There are now more servers which advertise support for IAKerb (passthrough
Kerberos authentication via proxy). IAKerb is a public extension industry
standard Kerberos protocol that allows a client without line-of-sight
to a Domain Controller to authenticate. There can be cases where we
would fail to mount if the server only advertises the OID for IAKerb
in SPNEGO/GSSAPI. Add code to allow us to still upcall to userspace
in these cases to obtain the Kerberos ticket.
Signed-off-by: Steve French <stfrench@microsoft.com>
struct FILE_ALL_INFO for level 263 (0x107) used by QPathInfo does not have
any IndexNumber, AccessFlags, IndexNumber1, CurrentByteOffset, Mode or
AlignmentRequirement members. So remove all of them.
Also adjust code in move_cifs_info_to_smb2() function which converts struct
FILE_ALL_INFO to struct smb2_file_all_info.
Fixed content of struct FILE_ALL_INFO was verified that is correct against:
* [MS-CIFS] section 2.2.8.3.10 SMB_QUERY_FILE_ALL_INFO
* Samba server implementation of trans2 query file/path for level 263
* Packet structure tests against Windows SMB servers
This change fixes CIFSSMBQFileInfo() and CIFSSMBQPathInfo() functions which
directly copy received FILE_ALL_INFO network buffers into kernel structures
of FILE_ALL_INFO type.
struct FILE_ALL_INFO is the response structure returned by the SMB server.
So the incorrect definition of this structure can lead to returning bogus
information in stat() call.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
CIFS client is currently able to parse NFS-style symlinks, but is not able
to create them. This functionality is useful when the mounted SMB share is
used also by Windows NFS server (on Windows Server 2012 or new). It allows
interop of symlinks between SMB share mounted by Linux CIFS client and same
export from Windows NFS server mounted by some NFS client.
New symlinks would be created in NFS-style only in case the mount option
-o reparse=nfs is specified, which is not by default. So default CIFS
mounts are not affected by this change.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Native Windows sockets created by WinSock on Windows 10 April 2018 Update
(version 1803) or Windows Server 2019 (version 1809) or later versions is
reparse point with IO_REPARSE_TAG_AF_UNIX tag, with empty reparse point
data buffer and without any EAs.
Create AF_UNIX sockets in this native format if -o nonativesocket was not
specified.
This change makes AF_UNIX sockets created by Linux CIFS client compatible
with AF_UNIX sockets created by Windows applications on NTFS volumes.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull ceph updates from Ilya Dryomov:
"A fix for a memory leak from Antoine (marked for stable) and two
cleanups from Liang and Slava"
* tag 'ceph-for-6.14-rc1' of https://github.com/ceph/ceph-client:
ceph: exchange hardcoded value on NAME_MAX
ceph: streamline request head structures in MDS client
ceph: fix memory leak in ceph_mds_auth_match()
Pull orangefs fix from Mike Marshall:
"Fix a oob in orangefs_debug_write
I got a syzbot report: "slab-out-of-bounds Read in orangefs_debug_write"
Several people suggested fixes, I tested Al Viro's suggestion and made
this patch"
* tag 'for-linus-6.14-ofs4' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: fix a oob in orangefs_debug_write
Pull hostfs fix from Al Viro:
"Fix hostfs __dentry_name() string handling.
The use of strcpy() with overlapping source and destination is a UB;
original loop hadn't been. More to the point, the whole thing is much
easier done with memcpy() + memmove()"
* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
hostfs: fix string handling in __dentry_name()
Pull UML updates from Richard Weinberger:
- hostfs: Convert to writepages
- many cleanups: removal of dead macros, missing __init
* tag 'uml-for-linus-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: Remove unused asm/archparam.h header
um: Include missing headers in asm/pgtable.h
hostfs: Convert to writepages
um: rtc: use RTC time when calculating the alarm
um: Remove unused user_context function
um: Remove unused THREAD_NAME_LEN macro
um: Remove unused PGD_BOUND macro
um: Mark setup_env_path as __init
um: Mark install_fatal_handler as __init
um: Mark set_stklim as __init
um: Mark get_top_address as __init
um: Mark parse_cache_line as __init
um: Mark parse_host_cpu_flags as __init
um: Count iomem_size only once in physmem calculation
um: Remove obsolete fixmap support
um: Remove unused MODULES_LEN macro
Pull UBI and UBIFS updates from Richard Weinberger:
"UBI:
- New interface to dump detailed erase counters
- Fixes around wear-leveling
UBIFS:
- Minor cleanups
- Fix for TNC dumping code"
* tag 'ubifs-for-linus-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubi: ubi_get_ec_info: Fix compiling error 'cast specifies array type'
ubi: Implement ioctl for detailed erase counters
ubi: Expose interface for detailed erase counters
ubifs: skip dumping tnc tree when zroot is null
ubi: Revert "ubi: wl: Close down wear-leveling before nand is suspended"
ubifs: ubifs_dump_leb: remove return from end of void function
ubifs: dump_lpt_leb: remove return at end of void function
ubi: Add a check for ubi_num
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
Pull ntfs3 fixes from Konstantin Komarov:
- unify inode corruption marking and mark them as bad immediately upon
detection of an error in attribute enumeration
- folio cleanup
* tag 'ntfs3_for_6.14' of https://github.com/Paragon-Software-Group/linux-ntfs3:
fs/ntfs3: Unify inode corruption marking with _ntfs_bad_inode()
fs/ntfs3: Mark inode as bad as soon as error detected in mi_enum_attr()
ntfs3: Remove an access to page->index
Pull bcachefs fixes from Kent Overstreet:
- second half of a fix for a bug that'd been causing oopses on
filesystems using snapshots with memory pressure (key cache fills for
snaphots btrees are tricky)
- build fix for strange compiler configurations that double stack frame
size
- "journal stuck timeout" now takes into account device latency: this
fixes some spurious warnings, and the main remaining source of SRCU
lock hold time warnings (I'm no longer seeing this in my CI, so any
users still seeing this should definitely ping me)
- fix for slow/hanging unmounts (" Improve journal pin flushing")
- some more tracepoint fixes/improvements, to chase down the "rebalance
isn't making progress" issues
* tag 'bcachefs-2025-01-29' of git://evilpiepirate.org/bcachefs:
bcachefs: Improve trace_move_extent_finish
bcachefs: Fix trace_copygc
bcachefs: Journal writes are now IOPRIO_CLASS_RT
bcachefs: Improve journal pin flushing
bcachefs: fix bch2_btree_node_flags
bcachefs: rebalance, copygc enabled are runtime opts
bcachefs: Improve decompression error messages
bcachefs: bset_blacklisted_journal_seq is now AUTOFIX
bcachefs: "Journal stuck" timeout now takes into account device latency
bcachefs: Reduce stack frame size of __bch2_str_hash_check_key()
bcachefs: Fix btree_trans_peek_key_cache()
This new mount option allows to completely disable creating new reparse
points. When -o sfu or -o mfsymlinks or -o symlink= is not specified then
creating any special file (fifo, socket, symlink, block and char) will fail
with -EOPNOTSUPP error.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently Linux CIFS client creates a new symlink of the first flavor which
is allowed by mount options, parsed in this order: -o (no)mfsymlinks,
-o (no)sfu, -o (no)unix (+ its aliases) and -o reparse=[type].
Introduce a new mount option -o symlink= for explicitly choosing a symlink
flavor. Possible options are:
-o symlink=default - The default behavior, like before this change.
-o symlink=none - Disallow creating a new symlinks
-o symlink=native - Create as native SMB symlink reparse point
-o symlink=unix - Create via SMB1 unix extension command
-o symlink=mfsymlinks - Create as regular file of mfsymlinks format
-o symlink=sfu - Create as regular system file of SFU format
-o symlink=nfs - Create as NFS reparse point
-o symlink=wsl - Create as WSL reparse point
So for example specifying -o sfu,mfsymlinks,symlink=native will allow to
parse symlinks also of SFU and mfsymlinks types (which are disabled by
default unless mount option is explicitly specified), but new symlinks will
be created under native SMB type (which parsing is always enabled).
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
If the SMB symlink is stored on NT server in absolute form then it points
to the NT object hierarchy, which is different from POSIX one and needs
some conversion / mapping.
To make interoperability with Windows SMB server and WSL subsystem, reuse
its logic of mapping between NT paths and POSIX paths into Linux SMB
client.
WSL subsystem on Windows uses for -t drvfs mount option -o symlinkroot=
which specifies the POSIX path where are expected to be mounted lowercase
Windows drive letters (without colon).
Do same for Linux SMB client and add a new mount option -o symlinkroot=
which mimics the drvfs mount option of the same name. It specifies where in
the Linux VFS hierarchy is the root of the DOS / Windows drive letters, and
translates between absolute NT-style symlinks and absolute Linux VFS
symlinks. Default value of symlinkroot is "/mnt", same what is using WSL.
Note that DOS / Windows drive letter symlinks are just subset of all
possible NT-style symlinks. Drive letters live in NT subtree \??\ and
important details about NT paths and object hierarchy are in the comments
in this change.
When symlink target location from non-POSIX SMB server is in absolute form
(indicated by absence of SYMLINK_FLAG_RELATIVE) then it is converted to
Linux absolute symlink according to symlinkroot configuration.
And when creating a new symlink on non-POSIX SMB server in absolute form
then Linux absolute target is converted to NT-style according to
symlinkroot configuration.
When SMB server is POSIX, then this change does not affect neither reading
target location of symlink, nor creating a new symlink. It is expected that
POSIX SMB server works with POSIX paths where the absolute root is /.
This change improves interoperability of absolute SMB symlinks with Windows
SMB servers.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
For checking if path is reparse point and setting data->reparse_point
member, it is enough to check if ATTR_REPARSE is present.
It is not required to call CIFS_open() without OPEN_REPARSE_POINT and
checking for -EOPNOTSUPP error code.
Signed-off-by: Pali Rohár <pali@kernel.org>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Member 'symlink' is part of the union in struct cifs_open_info_data. Its
value is assigned on few places, but is always read through another union
member 'reparse_point'. So to make code more readable, always use only
'reparse_point' member and drop whole union structure. No function change.
Signed-off-by: Pali Rohár <pali@kernel.org>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
