Although very unlikely that the tlink pointer would be null in this case,
get_next_mid function can in theory return null (but not an error)
so need to check for null (not for IS_ERR, which can not be returned
here).
Address warning:
fs/smbfs_client/connect.c:2392 cifs_match_super()
warn: 'tlink' isn't an ERR_PTR
Pointed out by Dan Carpenter via smatch code analysis tool
CC: stable@vger.kernel.org
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Address warning:
fs/smbfs_client/misc.c:273 header_assemble()
warn: variable dereferenced before check 'treeCon->ses->server'
Pointed out by Dan Carpenter via smatch code analysis tool
Although the check is likely unneeded, adding it makes the code
more consistent and easier to read, as the same check is
done elsewhere in the function.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Address warning:
fs/smbfs_client/smb2pdu.c:2425 create_sd_buf()
warn: struct type mismatch 'smb3_acl vs cifs_acl'
Pointed out by Dan Carpenter via smatch code analysis tool
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Clear CIFS_INO_MODIFIED_ATTR bit from inode flags after
updating mtime and ctime
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Steve French <stfrench@microsoft.com>
Deal with some warnings generated from make W=1:
(1) Add/remove/fix kerneldoc parameters descriptions.
(2) Turn cifs' rqst_page_get_length()'s banner comment into a kerneldoc
comment. It should probably be prefixed with "cifs_" though.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The problem is the mismatched types between "ctx->total_len" which is
an unsigned int, "rc" which is an int, and "ctx->rc" which is a
ssize_t. The code does:
ctx->rc = (rc == 0) ? ctx->total_len : rc;
We want "ctx->rc" to store the negative "rc" error code. But what
happens is that "rc" is type promoted to a high unsigned int and
'ctx->rc" will store the high positive value instead of a negative
value.
The fix is to change "rc" from an int to a ssize_t.
Fixes: c610c4b619 ("CIFS: Add asynchronous write support through kernel AIO")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Close file immediately when lock is set.
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Below traces are observed during fsstress and system got hung.
[ 130.698396] watchdog: BUG: soft lockup - CPU#6 stuck for 26s!
Cc: stable@vger.kernel.org # 5.13+
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
During unlink/rename instead of closing all the deferred handles
under tcon, close only handles under the requested dentry.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Correct kernel-doc comments pointed out by the
automated kernel test robot.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
checkpatch complains about source files with filenames (e.g. in
these cases just below the SPDX header in comments at the top of
various files in fs/cifs). It also is helpful to change this now
so will be less confusing when the parent directory is renamed
e.g. from fs/cifs to fs/smb_client (or fs/smbfs)
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Cached root file was not being completely invalidated sometimes.
Reproducing:
- With a DFS share with 2 targets, one disabled and one enabled
- start some I/O on the mount
# while true; do ls /mnt/dfs; done
- at the same time, disable the enabled target and enable the disabled
one
- wait for DFS cache to expire
- on reconnect, the previous cached root handle should be invalid, but
open_cached_dir_by_dentry() will still try to use it, but throws a
use-after-free warning (kref_get())
Make smb2_close_cached_fid() invalidate all fields every time, but only
send an SMB2_close() when the entry is still valid.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
The FSCTL definitions are in smbfsctl.h which should be
shared by client and server. Move the updated version of
smbfsctl.h into smbfs_common and have the client code use
it (subsequent patch will change the server to use this
common version of the header).
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
As we move to common code between client and server, we have
been asked to make the names less confusing, and refer less
to "cifs" and more to words which include "smb" instead to
e.g. "smbfs" for the client (we already have "ksmbd" for the
kernel server, and "smbd" for the user space Samba daemon).
So to be more consistent in the naming of common code between
client and server and reduce the risk of merge conflicts as
more common code is added - rename "cifs_common" to
"smbfs_common" (in future releases we also will rename
the fs/cifs directory to fs/smbfs)
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add some missing defines used by ksmbd to the client
version of smbfsctl.h, and add a missing newer define
mentioned in the protocol definitions (MS-FSCC).
This will also make it easier to move to common code.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag '5.15-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs client updates from Steve French:
"Eleven cifs/smb3 client fixes:
- mostly restructuring to allow disabling less secure algorithms
(this will allow eventual removing rc4 and md4 from general use in
the kernel)
- four fixes, including two for stable
- enable r/w support with fscache and cifs.ko
I am working on a larger set of changes (the usual ... multichannel,
auth and signing improvements), but wanted to get these in earlier to
reduce chance of merge conflicts later in the merge window"
* tag '5.15-rc-smb3-fixes-part1' of git://git.samba.org/sfrench/cifs-2.6:
cifs: Do not leak EDEADLK to dgetents64 for STATUS_USER_SESSION_DELETED
cifs: add cifs_common directory to MAINTAINERS file
cifs: cifs_md4 convert to SPDX identifier
cifs: create a MD4 module and switch cifs.ko to use it
cifs: fork arc4 and create a separate module for it for cifs and other users
cifs: remove support for NTLM and weaker authentication algorithms
cifs: enable fscache usage even for files opened as rw
oid_registry: Add OIDs for missing Spnego auth mechanisms to Macs
smb3: fix posix extensions mount option
cifs: fix wrong release in sess_alloc_buffer() failed path
CIFS: Fix a potencially linear read overflow
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Merge tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fs hole punching vs cache filling race fixes from Jan Kara:
"Fix races leading to possible data corruption or stale data exposure
in multiple filesystems when hole punching races with operations such
as readahead.
This is the series I was sending for the last merge window but with
your objection fixed - now filemap_fault() has been modified to take
invalidate_lock only when we need to create new page in the page cache
and / or bring it uptodate"
* tag 'hole_punch_for_v5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
filesystems/locking: fix Malformed table warning
cifs: Fix race between hole punch and page fault
ceph: Fix race between hole punch and page fault
fuse: Convert to using invalidate_lock
f2fs: Convert to using invalidate_lock
zonefs: Convert to using invalidate_lock
xfs: Convert double locking of MMAPLOCK to use VFS helpers
xfs: Convert to use invalidate_lock
xfs: Refactor xfs_isilocked()
ext2: Convert to using invalidate_lock
ext4: Convert to use mapping->invalidate_lock
mm: Add functions to lock invalidate_lock for two mappings
mm: Protect operations adding pages to page cache with invalidate_lock
documentation: Sync file_operations members with reality
mm: Fix comments mentioning i_mutex
RHBZ: 1994393
If we hit a STATUS_USER_SESSION_DELETED for the Create part in the
Create/QueryDirectory compound that starts a directory scan
we will leak EDEADLK back to userspace and surprise glibc and the application.
Pick this up initiate_cifs_search() and retry a small number of tries before we
return an error to userspace.
Cc: stable@vger.kernel.org
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
MD4 support will likely be removed from the crypto directory, but
is needed for compression of NTLMSSP in SMB3 mounts.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We can not drop ARC4 and basically destroy CIFS connectivity for
almost all CIFS users so create a new forked ARC4 module that CIFS and other
subsystems that have a hard dependency on ARC4 can use.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
for SMB1.
This removes the dependency to DES.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
So far, the fscache implementation we had supports only
a small set of use cases. Particularly for files opened
with O_RDONLY.
This commit enables it even for rw based file opens. It
also enables the reuse of cached data in case of mount
option (cache=singleclient) where it is guaranteed that
this is the only client (and server) which operates on
the files. There's also a single line change in fscache.c
to get around a bug seen in fscache.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We were incorrectly initializing the posix extensions in the
conversion to the new mount API.
CC: <stable@vger.kernel.org> # 5.11+
Reported-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Suggested-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
smb_buf is allocated by small_smb_init_no_tc(), and buf type is
CIFS_SMALL_BUFFER, so we should use cifs_small_buf_release() to
release it in failed path.
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
strlcpy() reads the entire source buffer first. This read may exceed the
destination size limit. This is both inefficient and can lead to linear
read overflows if a source string is not NUL-terminated.
Also, the strnlen() call does not avoid the read overflow in the strlcpy
function when a not NUL-terminated string is passed.
So, replace this block by a call to kstrndup() that avoids this type of
overflow and does the same.
Fixes: 066ce68994 ("cifs: rename cifs_strlcpy_to_host and make it use new functions")
Signed-off-by: Len Baker <len.baker@gmx.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
During unlink/rename/lease break, deferred work for close is
scheduled immediately but in an asynchronous manner which might
lead to race with actual(unlink/rename) commands.
This change will schedule close synchronously which will avoid
the race conditions with other commands.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: stable@vger.kernel.org # 5.13
Signed-off-by: Steve French <stfrench@microsoft.com>
When rename is executed on directory which has files for which
close is deferred, then rename will fail with EACCES.
This patch will try to close all deferred files when EACCES is received
and retry rename on a directory.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Cc: stable@vger.kernel.org # 5.13
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
RHBZ: 1972502
PATH_MAX is 4096 but PAGE_SIZE can be >4096 on some architectures
such as ppc and would thus write beyond the end of the actual object.
Cc: <stable@vger.kernel.org>
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Suggested-by: Brian foster <bfoster@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We used to follow the rule earlier that the create SD context
always be a multiple of 8. However, with the change:
cifs: refactor create_sd_buf() and and avoid corrupting the buffer
...we recompute the length, and we failed that rule.
Fixing that with this change.
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We lost parsing of backupuid in the switch to new mount API.
Add it back.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Cc: <stable@vger.kernel.org> # v5.11+
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Clang detected a problem with rc possibly being unitialized
(when length is zero) in a recently added fallocate code path.
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
readpage was calculating the offset of the page incorrectly
for the case of large swapcaches.
loff_t offset = (loff_t)page->index << PAGE_SHIFT;
As pointed out by Matthew Wilcox, this needs to use
page_file_offset() to calculate the offset instead.
Pages coming from the swap cache have page->index set
to their index within the swapcache, not within the backing
file. For a sufficiently large swapcache, we could have
overlapping values of page->index within the same backing file.
Suggested by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: <stable@vger.kernel.org> # v5.7+
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Remove the conditional checking for out_data_len and skipping the fallocate
if it is 0. This is wrong will actually change any legitimate the fallocate
where the entire region is unallocated into a no-op.
Additionally, before allocating the range, if FALLOC_FL_KEEP_SIZE is set then
we need to clamp the length of the fallocate region as to not extend the size of the file.
Fixes: 966a3cb7c7 ("cifs: improve fallocate emulation")
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Coverity also complains about the way we calculate the offset
(starting from the address of a 4 byte array within the
header structure rather than from the beginning of the struct
plus 4 bytes) for SMB1 CIFSPOSIXDelFile. This changeset
doesn't change the address but makes it slightly clearer.
Addresses-Coverity: 711519 ("Out of bounds write")
Signed-off-by: Steve French <stfrench@microsoft.com>
Coverity also complains about the way we calculate the offset
(starting from the address of a 4 byte array within the
header structure rather than from the beginning of the struct
plus 4 bytes) for SMB1 CIFSPOSIXCreate. This changeset
doesn't change the address but makes it slightly clearer.
Addresses-Coverity: 711518 ("Out of bounds write")
Signed-off-by: Steve French <stfrench@microsoft.com>
When remouting a DFS share, force a new DFS referral of the path and
if the currently cached targets do not match any of the new targets or
there was no cached targets, then mark it for reconnect.
For example:
$ mount //dom/dfs/link /mnt -o username=foo,password=bar
$ ls /mnt
oldfile.txt
change target share of 'link' in server settings
$ mount /mnt -o remount,username=foo,password=bar
$ ls /mnt
newfile.txt
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
We only allow sending single credit writes through the SMB2_write() synchronous
api so split this into smaller chunks.
Fixes: 966a3cb7c7 ("cifs: improve fallocate emulation")
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reported-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Make sure that we do not share tcp sessions of dfs mounts when
mounting regular shares that connect to same server. DFS connections
rely on a single instance of tcp in order to do failover properly in
cifs_reconnect().
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
When sending the compression context to some servers, they rejected
the SMB3.1.1 negotiate protocol because they expect the compression
context to have a data length of a multiple of 8.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We have a few ref counters srv_count, ses_count and
tc_count which we use for ref counting. Added a WARN_ON
during the decrement of each of these counters to make
sure that they don't go below their minimum values.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although it is unlikely to be have ended up with a null
session pointer calling cifs_try_adding_channels in cifs_mount.
Coverity correctly notes that we are already checking for
it earlier (when we return from do_dfs_failover), so at
a minimum to clarify the code we should make sure we also
check for it when we exit the loop so we don't end up calling
cifs_try_adding_channels or mount_setup_tlink with a null
ses pointer.
Addresses-Coverity: 1505608 ("Derefernce after null check")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
When there is no cached DFS referral of tcon->dfs_path, then reconnect
to same share.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Because the out of range assignment to bit fields
are compiler-dependant, the fields could have wrong
value.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=213565
cruid should only be used for the initial mount and after this we should use the current
users credentials.
Ignore the original cruid mount argument when creating a new context for a multiuser mount
following a DFS link.
Fixes: 24e0a1eff9 ("cifs: switch to new mount api")
Cc: stable@vger.kernel.org # 5.11+
Reported-by: Xiaoli Feng <xifeng@redhat.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
We recently fixed DNS resolution of the server hostname during reconnect.
However, server IP address may change, even when the old one continues
to server (although sub-optimally).
We should schedule the next DNS resolution based on the TTL of
the DNS record used for the last resolution. This way, we resolve the
server hostname again when a DNS record expires.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Cc: <stable@vger.kernel.org> # v5.11+
Signed-off-by: Steve French <stfrench@microsoft.com>
Cifs has a following race between hole punching and page fault:
CPU1 CPU2
smb3_fallocate()
smb3_punch_hole()
truncate_pagecache_range()
filemap_fault()
- loads old data into the
page cache
SMB2_ioctl(..., FSCTL_SET_ZERO_DATA, ...)
And now we have stale data in the page cache. Fix the problem by locking
out faults (as well as reads) using mapping->invalidate_lock while hole
punch is running.
CC: Steve French <sfrench@samba.org>
CC: linux-cifs@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
The optional @ref parameter might contain an NULL node_name, so
prevent dereferencing it in cifs_compose_mount_options().
Addresses-Coverity: 1476408 ("Explicit null dereferenced")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Support for faster packet signing (using GMAC instead of CMAC) can
now be negotiated to some newer servers, including Windows.
See MS-SMB2 section 2.2.3.17.
This patch adds support for sending the new negotiate context
with the first of three supported signing algorithms (AES-CMAC)
and decoding the response. A followon patch will add support
for sending the other two (including AES-GMAC, which is fastest)
and changing the signing algorithm used based on what was
negotiated.
To allow the client to request GMAC signing set module parameter
"enable_negotiate_signing" to 1.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>