Currently, the macro DUP_CTX_STR allocates new_ctx->field using
GFP_ATOMIC. DUP_CTX_STR is only used in smb3_fs_context_dup(), which
is never called in an atomic context. Using GFP_ATOMIC puts unnecessary
pressure on emergency memory pools.
Change GFP_ATOMIC to GFP_KERNEL.
Signed-off-by: Fredric Cover <fredric.cover.lkernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb3_reconfigure() moves strings out of cifs_sb->ctx before the
multichannel update, so a later failure can leave the live context
with NULL strings or options that do not match the session.
Stage the new ctx separately, commit it only on success, and restore
the snapshot on failure. Also make smb3_sync_session_ctx_passwords()
all-or-nothing.
Commit session passwords before channel updates so newly added channels
authenticate with the staged credentials.
Fixes: ef529f655a ("cifs: client: allow changing multichannel mount options on remount")
Reported-by: RAJASI MANDAL <rajasimandalos@gmail.com>
Closes: https://lore.kernel.org/lkml/CAEY6_V1+dzW3OD5zqXhsWyXwrDTrg5tAMGZ1AJ7_GAuRE+aevA@mail.gmail.com/
Link: https://lore.kernel.org/lkml/xkr2dlvgibq5j6gkcxd3yhhnj4atgxw2uy4eug2pxm7wy7nbms@iq6cf5taa65v/
Reviewed-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: DaeMyung Kang <charsyam@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Commit abdb1742a3 ("cifs: get rid of mount options string parsing")
removed the last caller.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Change the nolease mount option from fsparam_flag() to fsparam_flag_no()
so that both 'lease' and 'nolease' are accepted as valid mount options.
Previously, only 'nolease' was recognized. Passing 'lease' would fail
with an unknown parameter error (or be silently ignored with 'sloppy').
With this change:
- 'nolease' disables lease requests (same behavior as before)
- 'lease' explicitly enables lease requests
This also renames the enum value from Opt_nolease to Opt_lease and uses
result.negated to set ctx->no_lease, which is the standard pattern used
by other flag_no options in the cifs mount option parser.
Signed-off-by: Rajasi Mandal <rajasimandal@microsoft.com>
Reviewed-by: Meetakshi Setiya <msetiya@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add cifs_dbg(VFS, ...) statements to smb3_parse_devname() to provide
explicit feedback when parsing fails. Currently, the function returns
-EINVAL silently, making it difficult to debug mount failures caused
by malformed paths or missing share names.
Signed-off-by: Fredric Cover <FredTheDude@proton.me>
Acked-by: Henrique Carvalho <[2]henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When cifs_sanitize_prepath is called with an empty string or a string
containing only delimiters (e.g., "/"), the current logic attempts to
check *(cursor2 - 1) before cursor2 has advanced. This results in an
out-of-bounds read.
This patch adds an early exit check after stripping prepended
delimiters. If no path content remains, the function returns NULL.
The bug was identified via manual audit and verified using a
standalone test case compiled with AddressSanitizer, which
triggered a SEGV on affected inputs.
Signed-off-by: Fredric Cover <FredTheDude@proton.me>
Reviewed-by: Henrique Carvalho <[2]henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When retrans mount option was introduced, the default value was set
as 1. However, in the light of some bugs that this has exposed recently
we should change it to 0 and retain the old behaviour before this option
was introduced.
Cc: <stable@vger.kernel.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Use atomic_t for cifs_sb_info::mnt_cifs_flags as it's currently
accessed locklessly and may be changed concurrently in mount/remount
and reconnect paths.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
After commit 1ef15fbe67 ("cifs: client: enforce consistent handling
of multichannel and max_channels"), invalid mount options started to
be ignored, allowing cifs.ko to proceed with the mount instead of
baling out.
The problem was related to smb3_handle_conflicting_options() being
called even when an invalid parameter had been parsed, overwriting the
return value of vfs_parse_fs_string() in
smb3_fs_context_parse_monolithic().
Fix this by calling smb3_handle_conflicting_options() only when a
valid mount option has been passed.
Reproducer:
$ mount.cifs //srv/share /mnt -o ${opts}
$ mount -o remount,foo,${opts} /mnt # must fail
Fixes: 1ef15fbe67 ("cifs: client: enforce consistent handling of multichannel and max_channels")
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Cc: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Split SMB1 protocol defs into smb1pdu.h. This should perhaps go in the
common/ directory.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.org>
cc: Enzo Matsumiya <ematsumiya@suse.de>
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-kernel@vger.kernel.org
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
In smb3_reconfigure(), if smb3_sync_session_ctx_passwords() fails, the
function returns immediately without freeing and erasing the newly
allocated new_password and new_password2. This causes both a memory leak
and a potential information leak.
Fix this by calling kfree_sensitive() on both password buffers before
returning in this error case.
Fixes: 0f0e357902 ("cifs: during remount, make sure passwords are in sync")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Signed-off-by: Steve French <stfrench@microsoft.com>
Previously, the client did not update a session's channel state when
multichannel or max_channels mount options were changed via remount.
This led to inconsistent behavior and prevented enabling or disabling
multichannel support without a full unmount/remount cycle.
Enable dynamic reconfiguration of multichannel and max_channels during
remount by:
- Introducing smb3_sync_ses_chan_max(), a centralized function for
channel updates which synchronizes the session's channels with the
updated configuration.
- Replacing cifs_disable_secondary_channels() with
cifs_decrease_secondary_channels(), which accepts a disable_mchan
flag to support multichannel disable when the server stops supporting
multichannel.
- Updating remount logic to detect changes in multichannel or
max_channels and trigger appropriate session/channel updates.
Current limitation:
- The query_interfaces worker runs even when max_channels=1 so that
multichannel can be enabled later via remount without requiring an
unmount. This is a temporary approach and may be refined in the
future.
Users can safely modify multichannel and max_channels on an existing
mount. The client will correctly adjust the session's channel state to
match the new configuration, preserving durability where possible and
avoiding unnecessary disconnects.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Rajasi Mandal <rajasimandal@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Make some preparatory cleanups prior to running a script to organise the
function declarations within the fs/smb/client/ headers. These include:
(1) Remove "inline" from the dummy cifs_proc_init/clean() functions as
they are in a .c file.
(2) Move should_compress()'s kdoc comment to the .c file and remove kdoc
markers from the comments.
(3) Rename CIFS_ALLOW_INSECURE_LEGACY in #endif comments to have CONFIG_
on the front to allow the script to recognise it.
(4) Don't let comments have bare words at the left margin as that confused
the simplistic function detection code in the script.
(5) Adjust some argument lists so that when and if the cleanup script is
run they don't end up over 100 chars.
(6) Fix a few comments to have missing '*' added or the "*/" moved to
their own lines so that checkpatch doesn't moan over the cleanup
script patch.
(7) Move struct cifs_calc_sig_ctx to cifsglob.h.
(8) Remove some __KERNEL__ conditionals.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Previously, the behavior of the multichannel and max_channels mount
options was inconsistent and order-dependent. For example, specifying
"multichannel,max_channels=1" would result in 2 channels, while
"max_channels=1,multichannel" would result in 1 channel. Additionally,
conflicting combinations such as "nomultichannel,max_channels=3" or
"multichannel,max_channels=1" did not produce errors and could lead to
unexpected channel counts.
This commit introduces two new fields in smb3_fs_context to explicitly
track whether multichannel and max_channels were specified during
mount. The option parsing and validation logic is updated to ensure:
- The outcome is no longer dependent on the order of options.
- Conflicting combinations (e.g., "nomultichannel,max_channels=3" or
"multichannel,max_channels=1") are detected and result in an error.
- The number of channels created is consistent with the specified
options.
This improves the reliability and predictability of mount option
handling for SMB3 multichannel support.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Rajasi Mandal <rajasimandal@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add proper cleanup of ctx->source and fc->source to the
cifs_parse_mount_err error handler. This ensures that memory allocated
for the source strings is correctly freed on all error paths, matching
the cleanup already performed in the success path by
smb3_cleanup_fs_context_contents().
Pointers are also set to NULL after freeing to prevent potential
double-free issues.
This change fixes a memory leak originally detected by syzbot. The
leak occurred when processing Opt_source mount options if an error
happened after ctx->source and fc->source were successfully
allocated but before the function completed.
The specific leak sequence was:
1. ctx->source = smb3_fs_context_fullpath(ctx, '/') allocates memory
2. fc->source = kstrdup(ctx->source, GFP_KERNEL) allocates more memory
3. A subsequent error jumps to cifs_parse_mount_err
4. The old error handler freed passwords but not the source strings,
causing the memory to leak.
This issue was not addressed by commit e8c73eb7db ("cifs: client:
fix memory leak in smb3_fs_context_parse_param"), which only fixed
leaks from repeated fsconfig() calls but not this error path.
Patch updated with minor change suggested by kernel test robot
Reported-by: syzbot+87be6809ed9bf6d718e3@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=87be6809ed9bf6d718e3
Fixes: 24e0a1eff9 ("cifs: switch to new mount api")
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Shaurya Rane <ssrane_b23@ee.vjti.ac.in>
Signed-off-by: Steve French <stfrench@microsoft.com>
Since the maximum return value of strnlen(..., CIFS_MAX_USERNAME_LEN)
is CIFS_MAX_USERNAME_LEN, length check in smb3_fs_context_parse_param()
is always FALSE and invalid.
Fix the comparison in if statement.
Signed-off-by: Yiqi Sun <sunyiqixm@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The user calls fsconfig twice, but when the program exits, free() only
frees ctx->source for the second fsconfig, not the first.
Regarding fc->source, there is no code in the fs context related to its
memory reclamation.
To fix this memory leak, release the source memory corresponding to ctx
or fc before each parsing.
syzbot reported:
BUG: memory leak
unreferenced object 0xffff888128afa360 (size 96):
backtrace (crc 79c9c7ba):
kstrdup+0x3c/0x80 mm/util.c:84
smb3_fs_context_parse_param+0x229b/0x36c0 fs/smb/client/fs_context.c:1444
BUG: memory leak
unreferenced object 0xffff888112c7d900 (size 96):
backtrace (crc 79c9c7ba):
smb3_fs_context_fullpath+0x70/0x1b0 fs/smb/client/fs_context.c:629
smb3_fs_context_parse_param+0x2266/0x36c0 fs/smb/client/fs_context.c:1438
Reported-by: syzbot+72afd4c236e6bc3f4bac@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=72afd4c236e6bc3f4bac
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag '6.18-rc-part1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull smb client updates from Steve French:
- Fix oops in crypt message
- Remove duplicate arc4 code
- Fix potential io_uring reconnect
- Two important directory leases fixes and three perf improvements
- Three minor cleanups
- Four debug improvements (e.g. for showing more information on leases,
and one for adding more helpful information on reconnect)
* tag '6.18-rc-part1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: client: force multichannel=off when max_channels=1
smb client: fix bug with newly created file in cached dir
smb: client: short-circuit negative lookups when parent dir is fully cached
smb: client: short-circuit in open_cached_dir_by_dentry() if !dentry
smb: client: remove pointless cfid->has_lease check
smb: client: transport: minor indentation style fix
smb: client: transport: avoid reconnects triggered by pending task work
smb: client: remove unused fid_lock
smb: client: update cfid->last_access_time in open_cached_dir_by_dentry()
smb: client: ensure open_cached_dir_by_dentry() only returns valid cfid
smb: client: account smb directory cache usage and per-tcon totals
smb: client: add drop_dir_cache module parameter to invalidate cached dirents
smb: client: show lease state as R/H/W (or NONE) in open_files
smb: client: fix crypto buffers in non-linear memory
smb: Use arc4 library instead of duplicate arc4 code
smb: client: add tcon information to smb2_reconnect() debug messages
Previously, specifying both multichannel and max_channels=1 as mount
options would leave multichannel enabled, even though it is not
meaningful when only one channel is allowed. This led to confusion and
inconsistent behavior, as the client would advertise multichannel
capability but never establish secondary channels.
Fix this by forcing multichannel to false whenever max_channels=1,
ensuring the mount configuration is consistent and matches user intent.
This prevents the client from advertising or attempting multichannel
support when it is not possible.
Signed-off-by: Rajasi Mandal <rajasimandal@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Absolute majority of callers are passing the 4th argument equal to
strlen() of the 3rd one.
Drop the v_size argument, add vfs_parse_fs_qstr() for the cases that
want independent length.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
SMB3.1.1 POSIX mounts require sockets to be created with NFS reparse
points.
Cc: linux-cifs@vger.kernel.org
Cc: Ralph Boehme <slow@samba.org>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-by: Matthew Richardson <m.richardson@ed.ac.uk>
Closes: https://marc.info/?i=1124e7cd-6a46-40a6-9f44-b7664a66654b@ed.ac.uk
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB3.1.1 POSIX mounts require symlinks to be created natively with
IO_REPARSE_TAG_SYMLINK reparse point.
Cc: linux-cifs@vger.kernel.org
Cc: Ralph Boehme <slow@samba.org>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-by: Matthew Richardson <m.richardson@ed.ac.uk>
Closes: https://marc.info/?i=1124e7cd-6a46-40a6-9f44-b7664a66654b@ed.ac.uk
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steal string reference from @param->string rather than duplicating it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steal string reference from @param->string rather than duplicating it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steal string reference from @param->string rather than duplicating it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steal string reference from @param->string rather than duplicating it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Steal string reference from @param->string rather than duplicating it.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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 12b466eb52 ("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: 12b466eb52 ("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>
Make all IO sizes multiple of PAGE_SIZE, either negotiated by the
server or passed through rsize, wsize and bsize mount options, to
prevent from breaking DIO reads and writes against servers that
enforce alignment as specified in MS-FSA 2.1.5.3 and 2.1.5.4.
Cc: linux-cifs@vger.kernel.org
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently SMB client always tries to initialize NetBIOS session when the
server port is 139. This is useful for default cases, but nowadays when
using non-standard routing or testing between VMs, it is common that
servers are listening on non-standard ports.
So add a new mount option -o nbsessinit and -o nonbsessinit which either
forces initialization or disables initialization regardless of server port
number.
This allows Linux SMB client to connect to older SMB1 server listening on
non-standard port, which requires initialization of NetBIOS session, by
using additional mount options -o port= and -o nbsessinit.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
During mount option processing and negotiation with the server, the
original user-specified rsize/wsize values were being modified directly.
This makes it impossible to recover these values after a connection
reset, leading to potential degraded performance after reconnection.
The other problem is that When negotiating read and write sizes, there are
cases where the negotiated values might calculate to zero, especially
during reconnection when server->max_read or server->max_write might be
reset. In general, these values come from the negotiation response.
According to MS-SMB2 specification, these values should be at least 65536
bytes.
This patch improves IO parameter handling:
1. Adds vol_rsize and vol_wsize fields to store the original user-specified
values separately from the negotiated values
2. Uses got_rsize/got_wsize flags to determine if values were
user-specified rather than checking for non-zero values, which is more
reliable
3. Adds a prevent_zero_iosize() helper function to ensure IO sizes are
never negotiated down to zero, which could happen in edge cases like
when server->max_read/write is zero
The changes make the CIFS client more resilient to unusual server
responses and reconnection scenarios, preventing potential failures
when IO sizes are calculated to be zero.
Signed-off-by: Wang Zhaolong <wangzhaolong1@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The echo_interval is not limited in any way during mounting,
which makes it possible to write a large number to it. This can
cause an overflow when multiplying ctx->echo_interval by HZ in
match_server().
Add constraints for echo_interval to smb3_fs_context_parse_param().
Found by Linux Verification Center (linuxtesting.org) with Svace.
Fixes: adfeb3e00e ("cifs: Make echo interval tunable")
Cc: stable@vger.kernel.org
Signed-off-by: Roman Smirnov <r.smirnov@omp.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB1 protocol supports non-UNICODE (8-bit OEM character set) and
UNICODE (UTF-16) modes.
Linux SMB1 client implements both of them but currently does not allow to
choose non-UNICODE mode when SMB1 server announce UNICODE mode support.
This change adds a new mount option -o nounicode to disable UNICODE mode
and force usage of non-UNICODE (8-bit OEM character set) mode.
This allows to test non-UNICODE implementation of Linux SMB1 client against
any SMB1 server, including modern and recent Windows SMB1 server.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Windows SMB servers (including SMB2+) which are working over RFC1001
require that Netbios server name specified in RFC1001 Session Request
packet is same as the UNC host name. Netbios server name can be already
specified manually via -o servern= option.
With this change the RFC1001 server name is set automatically by extracting
the hostname from the mount source.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
User-provided mount parameter closetimeo of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 5efdd9122e ("smb3: allow deferred close timeout to be configurable")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
User-provided mount parameter actimeo of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 6d20e8406f ("cifs: add attribute cache timeout (actimeo) tunable")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
User-provided mount parameter acdirmax of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 4c9f948142 ("cifs: Add new mount parameter "acdirmax" to allow caching directory metadata")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
User-provided mount parameter acregmax of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 5780464614 ("cifs: Add new parameter "acregmax" for distinct file and directory metadata timeout")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
When mounting a CIFS share with 'guest' mount option, mount.cifs(8)
will set empty password= and password2= options. Currently we only
handle empty strings from user= and password= options, so the mount
will fail with
cifs: Bad value for 'password2'
Fix this by handling empty string from password2= option as well.
Link: https://bbs.archlinux.org/viewtopic.php?id=303927
Reported-by: Adam Williamson <awilliam@redhat.com>
Closes: https://lore.kernel.org/r/83c00b5fea81c07f6897a5dd3ef50fd3b290f56c.camel@redhat.com
Fixes: 35f834265e ("smb3: fix broken reconnect when password changing on the server by allowing password rotation")
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
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>
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>
Old Windows servers will return not fully qualified DFS targets by
default as specified in
MS-DFSC 3.2.5.5 Receiving a Root Referral Request or Link Referral
Request
| Servers SHOULD<30> return fully qualified DNS host names of
| targets in responses to root referral requests and link referral
| requests.
| ...
| <30> Section 3.2.5.5: By default, Windows Server 2003, Windows
| Server 2008, Windows Server 2008 R2, Windows Server 2012, and
| Windows Server 2012 R2 return DNS host names that are not fully
| qualified for targets.
Fix this by converting all NetBIOS host names from DFS targets to
FQDNs and try resolving them first if DNS domain name was provided in
NTLMSSP CHALLENGE_MESSAGE message from previous SMB2_SESSION_SETUP.
This also prevents the client from translating the DFS target
hostnames to another domain depending on the network domain search
order.
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Unlock before returning if smb3_sync_session_ctx_passwords() fails.
Fixes: 7e654ab7da03 ("cifs: during remount, make sure passwords are in sync")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Bharath SM <bharathsm@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This fixes scenarios where remount can overwrite the only currently
working password, breaking reconnect.
We recently introduced a password2 field in both ses and ctx structs.
This was done so as to allow the client to rotate passwords for a mount
without any downtime. However, when the client transparently handles
password rotation, it can swap the values of the two password fields
in the ses struct, but not in smb3_fs_context struct that hangs off
cifs_sb. This can lead to a situation where a remount unintentionally
overwrites a working password in the ses struct.
In order to fix this, we first get the passwords in ctx struct
in-sync with ses struct, before replacing them with what the passwords
that could be passed as a part of remount.
Also, in order to avoid race condition between smb2_reconnect and
smb3_reconfigure, we make sure to lock session_mutex before changing
password and password2 fields of the ses structure.
Fixes: 35f834265e ("smb3: fix broken reconnect when password changing on the server by allowing password rotation")
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Meetakshi Setiya <msetiya@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In the current implementation, the SMB filesystem on a mount point can
trigger upcalls from the kernel to the userspace to enable certain
functionalities like spnego, dns_resolution, amongst others. These upcalls
usually either happen in the context of the mount or in the context of an
application/user. The upcall handler for cifs, cifs.upcall already has
existing code which switches the namespaces to the caller's namespace
before handling the upcall. This behaviour is expected for scenarios like
multiuser mounts, but might not cover all single user scenario with
services such as Kubernetes, where the mount can happen from different
locations such as on the host, from an app container, or a driver pod
which does the mount on behalf of a different pod.
This patch introduces a new mount option called upcall_target, to
customise the upcall behaviour. upcall_target can take 'mount' and 'app'
as possible values. This aids use cases like Kubernetes where the mount
happens on behalf of the application in another container altogether.
Having this new mount option allows the mount command to specify where the
upcall should happen: 'mount' for resolving the upcall to the host
namespace, and 'app' for resolving the upcall to the ns of the calling
thread. This will enable both the scenarios where the Kerberos credentials
can be found on the application namespace or the host namespace to which
just the mount operation is "delegated".
Reviewed-by: Shyam Prasad <shyam.prasad@microsoft.com>
Reviewed-by: Bharath S M <bharathsm@microsoft.com>
Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Signed-off-by: Ritvik Budhiraja <rbudhiraja@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In smb3_reconfigure(), after duplicating ctx->password and
ctx->password2 with kstrdup(), we need to check for allocation
failures.
If ses->password allocation fails, return -ENOMEM.
If ses->password2 allocation fails, free ses->password, set it
to NULL, and return -ENOMEM.
Fixes: c1eb537bf4 ("cifs: allow changing password during remount")
Reviewed-by: David Howells <dhowells@redhat.com
Signed-off-by: Haoxiang Li <make24@iscas.ac.cn>
Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
