Use pr_fmt to standardize all logging for fs/cifs.
Some logging output had no CIFS: specific prefix.
Now all output has one of three prefixes:
o CIFS:
o CIFS: VFS:
o Root-CIFS:
Miscellanea:
o Convert printks to pr_<level>
o Neaten macro definitions
o Remove embedded CIFS: prefixes from formats
o Convert "illegal" to "invalid"
o Coalesce formats
o Add missing '\n' format terminations
o Consolidate multiple cifs_dbg continuations into single calls
o More consistent use of upper case first word output logging
o Multiline statement argument alignment and wrapping
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to handle workloads where it is important to make sure that
a buggy app did not delete content on the drive, the new mount option
"nodelete" allows standard permission checks on the server to work,
but prevents on the client any attempts to unlink a file or delete
a directory on that mount point. This can be helpful when running
a little understood app on a network mount that contains important
content that should not be deleted.
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Move some large data structures off the stack and into dynamically
allocated memory in the function smb2_ioctl_query_info
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move a lot of structures and arrays off the stack and into a dynamically
allocated structure instead.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The target iterator parameter "it" is not used in
reconn_setup_dfs_targets(), so just remove it.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to support reconnect to hostnames that resolve to same ip
address, besides relying on the currently set hostname to match DFS
targets, attempt to resolve the targets and then match their addresses
with the reconnected server ip address.
For instance, if we have two hostnames "FOO" and "BAR", and both
resolve to the same ip address, we would be able to handle failover in
DFS paths like
\\FOO\dfs\link1 -> [ \BAZ\share2 (*), \BAR\share1 ]
\\FOO\dfs\link2 -> [ \BAZ\share2 (*), \FOO\share1 ]
so when "BAZ" is no longer accessible, link1 and link2 would get
reconnected despite having different target hostnames.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If we mount a very specific DFS link
\\FS0.FOO.COM\dfs\link -> \FS0\share1, \FS1\share2
where its target list contains NB names ("FS0" & "FS1") rather than
FQDN ones ("FS0.FOO.COM" & "FS1.FOO.COM"), we end up connecting to
\FOO\share1 but server->hostname will have "FOO.COM". The reason is
because both "FS0" and "FS0.FOO.COM" resolve to same IP address and
they share same TCP server connection, but "FS0.FOO.COM" was the first
hostname set -- which is OK.
However, if the echo thread timeouts and we still have a good
connection to "FS0", in cifs_reconnect()
rc = generic_ip_connect(server) -> success
if (rc) {
...
reconn_inval_dfs_target(server, cifs_sb, &tgt_list,
&tgt_it);
...
}
...
it successfully reconnects to "FS0" server but does not set up next
DFS target - which should be the same target server "\FS0\share1" -
and server->hostname remains set to "FS0.FOO.COM" rather than "FS0",
as reconn_inval_dfs_target() would have it set to "FS0" if called
earlier.
Finally, in __smb2_reconnect(), the reconnect of tcons would fail
because tcon->ses->server->hostname (FS0.FOO.COM) does not match DFS
target's hostname (FS0).
Fix that by calling reconn_inval_dfs_target() before
generic_ip_connect() so server->hostname will get updated correctly
prior to reconnecting its tcons in __smb2_reconnect().
With "cifs: handle hostnames that resolve to same ip in failover"
patch
- The above problem would not occur.
- We could save an DNS query to find out that they both resolve to
the same ip address.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The variable rc is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The "nolease" mount option is only supported for SMB2+ mounts.
Fail with appropriate error message if vers=1.0 option is passed.
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Failed async writes that are requeued may not clean up a refcount
on the file, which can result in a leaked open. This scenario arises
very reliably when using persistent handles and a reconnect occurs
while writing.
cifs_writev_requeue only releases the reference if the write fails
(rc != 0). The server->ops->async_writev operation will take its own
reference, so the initial reference can always be released.
Signed-off-by: Adam McCoy <adam@forsedomani.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
As per POSIX, the correct spelling is EACCES:
include/uapi/asm-generic/errno-base.h:#define EACCES 13 /* Permission denied */
Fixes: b8f7442bc4 ("CIFS: refactor cifs_get_inode_info()")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB2_open_init() expects a pre-initialised lease_key when opening a
file with a lease, so set pfid->lease_key prior to calling it in
open_shroot().
This issue was observed when performing some DFS failover tests and
the lease key was never randomly generated.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
This patch is basically fixing the lookup of tcons (DFS specific) during
reconnect (smb2pdu.c:__smb2_reconnect) to update their prefix paths.
Previously, we relied on the TCP_Server_Info pointer
(misc.c:tcp_super_cb) to determine which tcon to update the prefix path
We could not rely on TCP server pointer to determine which super block
to update the prefix path when reconnecting tcons since it might map
to different tcons that share same TCP connection.
Instead, walk through all cifs super blocks and compare their DFS full
paths with the tcon being updated to.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
This disables tcon re-use for DFS shares.
tcon->dfs_path stores the path that the tcon should connect to when
doing failing over.
If that tcon is used multiple times e.g. 2 mounts using it with
different prefixpath, each will need a different dfs_path but there is
only one tcon. The other solution would be to split the tcon in 2
tcons during failover but that is much harder.
tcons could not be shared with DFS in cifs.ko because in a
DFS namespace like:
//domain/dfsroot -> /serverA/dfsroot, /serverB/dfsroot
//serverA/dfsroot/link -> /serverA/target1/aa/bb
//serverA/dfsroot/link2 -> /serverA/target1/cc/dd
you can see that link and link2 are two DFS links that both resolve to
the same target share (/serverA/target1), so cifs.ko will only contain a
single tcon for both link and link2.
The problem with that is, if we (auto)mount "link" and "link2", cifs.ko
will only contain a single tcon for both DFS links so we couldn't
perform failover or refresh the DFS cache for both links because
tcon->dfs_path was set to either "link" or "link2", but not both --
which is wrong.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We use a spinlock while we are reading and accessing the destination address for a server.
We need to also use this spinlock to protect when we are modifying this address from
reconn_set_ipaddr().
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
A dump_stack call for signature related errors can be too noisy
and not of much value in debugging such problems.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
Found a read performance issue when linux kernel page size is 64KB.
If linux kernel page size is 64KB and mount options cache=strict &
vers=2.1+, it does not support cifs_readpages(). Instead, it is using
cifs_readpage() and cifs_read() with maximum read IO size 16KB, which is
much slower than read IO size 1MB when negotiated SMB 2.1+. Since modern
SMB server supported SMB 2.1+ and Max Read Size can reach more than 64KB
(for example 1MB ~ 8MB), this patch check max_read instead of maxBuf to
determine whether server support readpages() and improve read performance
for page size 64KB & cache=strict & vers=2.1+, and for SMB1 it is more
cleaner to initialize server->max_read to server->maxBuf.
The client is a linux box with linux kernel 4.2.8,
page size 64KB (CONFIG_ARM64_64K_PAGES=y),
cpu arm 1.7GHz, and use mount.cifs as smb client.
The server is another linux box with linux kernel 4.2.8,
share a file '10G.img' with size 10GB,
and use samba-4.7.12 as smb server.
The client mount a share from the server with different
cache options: cache=strict and cache=none,
mount -tcifs //<server_ip>/Public /cache_strict -overs=3.0,cache=strict,username=<xxx>,password=<yyy>
mount -tcifs //<server_ip>/Public /cache_none -overs=3.0,cache=none,username=<xxx>,password=<yyy>
The client download a 10GbE file from the server across 1GbE network,
dd if=/cache_strict/10G.img of=/dev/null bs=1M count=10240
dd if=/cache_none/10G.img of=/dev/null bs=1M count=10240
Found that cache=strict (without patch) is slower read throughput and
smaller read IO size than cache=none.
cache=strict (without patch): read throughput 40MB/s, read IO size is 16KB
cache=strict (with patch): read throughput 113MB/s, read IO size is 1MB
cache=none: read throughput 109MB/s, read IO size is 1MB
Looks like if page size is 64KB,
cifs_set_ops() would use cifs_addr_ops_smallbuf instead of cifs_addr_ops,
/* check if server can support readpages */
if (cifs_sb_master_tcon(cifs_sb)->ses->server->maxBuf <
PAGE_SIZE + MAX_CIFS_HDR_SIZE)
inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
else
inode->i_data.a_ops = &cifs_addr_ops;
maxBuf is came from 2 places, SMB2_negotiate() and CIFSSMBNegotiate(),
(SMB2_MAX_BUFFER_SIZE is 64KB)
SMB2_negotiate():
/* set it to the maximum buffer size value we can send with 1 credit */
server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize),
SMB2_MAX_BUFFER_SIZE);
CIFSSMBNegotiate():
server->maxBuf = le32_to_cpu(pSMBr->MaxBufferSize);
Page size 64KB and cache=strict lead to read_pages() use cifs_readpage()
instead of cifs_readpages(), and then cifs_read() using maximum read IO
size 16KB, which is much slower than maximum read IO size 1MB.
(CIFSMaxBufSize is 16KB by default)
/* FIXME: set up handlers for larger reads and/or convert to async */
rsize = min_t(unsigned int, cifs_sb->rsize, CIFSMaxBufSize);
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Jones Syue <jonessyue@qnap.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We already dump these keys for SMB3, lets also dump it for SMB2
sessions so that we can use the session key in wireshark to check and validate
that the signatures are correct.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Add experimental support for allowing a swap file to be on an SMB3
mount. There are use cases where swapping over a secure network
filesystem is preferable. In some cases there are no local
block devices large enough, and network block devices can be
hard to setup and secure. And in some cases there are no
local block devices at all (e.g. with the recent addition of
remote boot over SMB3 mounts).
There are various enhancements that can be added later e.g.:
- doing a mandatory byte range lock over the swapfile (until
the Linux VFS is modified to notify the file system that an open
is for a swapfile, when the file can be opened "DENY_ALL" to prevent
others from opening it).
- pinning more buffers in the underlying transport to minimize memory
allocations in the TCP stack under the fs
- documenting how to create ACLs (on the server) to secure the
swapfile (or adding additional tools to cifs-utils to make it easier)
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
The noisy posix error message in readdir was supposed
to be an FYI (not enabled by default)
CIFS VFS: XXX dev 66306, reparse 0, mode 755
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
smbdirect support (SMB3 over RDMA) should be enabled by
default in many configurations.
It is not experimental and is stable enough and has enough
performance benefits to recommend that it be configured by
default. Change the "If unsure N" to "If unsure Y" in
the description of the configuration parameter.
Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Immediate packets should only be sent to peer when there are new
receive credits made available. New credits show up on freeing
receive buffer, not on receiving data.
Fix this by avoid unnenecessary work schedules.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When processing errors from ib_post_send(), the transport state needs to be
rolled back to the condition before the error.
Refactor the old code to make it easy to roll back on IB errors, and fix this.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CIFS uses pre-allocated crypto structures to calculate signatures for both
incoming and outgoing packets. In this way it doesn't need to allocate crypto
structures for every packet, but it requires a lock to prevent concurrent
access to crypto structures.
Remove the lock by allocating crypto structures on the fly for
incoming packets. At the same time, we can still use pre-allocated crypto
structures for outgoing packets, as they are already protected by transport
lock srv_mutex.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Recevie credits should be updated before sending the packet, not
before a work is scheduled. Also, the value needs roll back if
something fails and cannot send.
Signed-off-by: Long Li <longli@microsoft.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Sometimes the remote peer may return more send credits than the send queue
depth. If all the send credits are used to post senasd, we may overflow the
send queue.
Fix this by checking the send queue size before posting a send.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
As an optimization, SMBD tries to track two types of packets: packets with
payload and without payload. There is no obvious benefit or performance gain
to separately track two types of packets.
Just treat them as pending packets and merge the tracking code.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix tcon use-after-free and NULL ptr deref.
Customer system crashes with the following kernel log:
[462233.169868] CIFS VFS: Cancelling wait for mid 4894753 cmd: 14 => a QUERY DIR
[462233.228045] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.305922] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.306205] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347060] CIFS VFS: cifs_put_smb_ses: Session Logoff failure rc=-4
[462233.347107] CIFS VFS: Close unmatched open
[462233.347113] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
...
[exception RIP: cifs_put_tcon+0xa0] (this is doing tcon->ses->server)
#6 [...] smb2_cancelled_close_fid at ... [cifs]
#7 [...] process_one_work at ...
#8 [...] worker_thread at ...
#9 [...] kthread at ...
The most likely explanation we have is:
* When we put the last reference of a tcon (refcount=0), we close the
cached share root handle.
* If closing a handle is interrupted, SMB2_close() will
queue a SMB2_close() in a work thread.
* The queued object keeps a tcon ref so we bump the tcon
refcount, jumping from 0 to 1.
* We reach the end of cifs_put_tcon(), we free the tcon object despite
it now having a refcount of 1.
* The queued work now runs, but the tcon, ses & server was freed in
the meantime resulting in a crash.
THREAD 1
========
cifs_put_tcon => tcon refcount reach 0
SMB2_tdis
close_shroot_lease
close_shroot_lease_locked => if cached root has lease && refcount = 0
smb2_close_cached_fid => if cached root valid
SMB2_close => retry close in a thread if interrupted
smb2_handle_cancelled_close
__smb2_handle_cancelled_close => !! tcon refcount bump 0 => 1 !!
INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
queue_work(cifsiod_wq, &cancelled->work) => queue work
tconInfoFree(tcon); ==> freed!
cifs_put_smb_ses(ses); ==> freed!
THREAD 2 (workqueue)
========
smb2_cancelled_close_fid
SMB2_close(0, cancelled->tcon, ...); => use-after-free of tcon
cifs_put_tcon(cancelled->tcon); => tcon refcount reach 0 second time
*CRASH*
Fixes: d919131935 ("CIFS: Close cached root handle only if it has a lease")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
When encryption is used, smb2_transform_hdr is defined on the stack and is
passed to the transport. This doesn't work with RDMA as the buffer needs to
be DMA'ed.
Fix it by using kmalloc.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When a RDMA packet is received and server is extending send credits, we should
check and unblock senders immediately in IRQ context. Doing it in a worker
queue causes unnecessary delay and doesn't save much CPU on the receive path.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The packet size needs to take account of SMB2 header size and possible
encryption header size. This is only done when signing is used and it is for
RDMA send/receive, not read/write.
Also remove the dead SMBD code in smb2_negotiate_r(w)size.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It clarifies the code slightly to use SMB2_SIGNATURE_SIZE
define rather than 16.
Suggested-by: Henning Schild <henning.schild@siemens.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch is used to fix the bug in collect_uncached_read_data()
that rc is automatically converted from a signed number to an
unsigned number when the CIFS asynchronous read fails.
It will cause ctx->rc is error.
Example:
Share a directory and create a file on the Windows OS.
Mount the directory to the Linux OS using CIFS.
On the CIFS client of the Linux OS, invoke the pread interface to
deliver the read request.
The size of the read length plus offset of the read request is greater
than the maximum file size.
In this case, the CIFS server on the Windows OS returns a failure
message (for example, the return value of
smb2.nt_status is STATUS_INVALID_PARAMETER).
After receiving the response message, the CIFS client parses
smb2.nt_status to STATUS_INVALID_PARAMETER
and converts it to the Linux error code (rdata->result=-22).
Then the CIFS client invokes the collect_uncached_read_data function to
assign the value of rdata->result to rc, that is, rc=rdata->result=-22.
The type of the ctx->total_len variable is unsigned integer,
the type of the rc variable is integer, and the type of
the ctx->rc variable is ssize_t.
Therefore, during the ternary operation, the value of rc is
automatically converted to an unsigned number. The final result is
ctx->rc=4294967274. However, the expected result is ctx->rc=-22.
Signed-off-by: Yilu Lin <linyilu@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
xfstests generic/228 checks if fallocate respect RLIMIT_FSIZE.
After fallocate mode 0 extending enabled, we can hit this failure.
Fix this by check the new file size with vfs helper, return
error if file size is larger then RLIMIT_FSIZE(ulimit -f).
This patch has been tested by LTP/xfstests aginst samba and
Windows server.
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
New transform header structures. See recent updates
to MS-SMB2 adding section 2.2.42.1 and 2.2.42.2
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Additional compression capabilities can now be negotiated and a
new compression algorithm. Add the flags for these.
See newly updated MS-SMB2 sections 3.1.4.4.1 and 2.2.3.1.3
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Leaving PF_MEMALLOC set when exiting a kthread causes it to remain set
during do_exit(). That can confuse things. For example, if BSD process
accounting is enabled and the accounting file has FS_SYNC_FL set and is
located on an ext4 filesystem without a journal, then do_exit() can end
up calling ext4_write_inode(). That triggers the
WARN_ON_ONCE(current->flags & PF_MEMALLOC) there, as it assumes
(appropriately) that inodes aren't written when allocating memory.
This was originally reported for another kernel thread, xfsaild() [1].
cifs_demultiplex_thread() also exits with PF_MEMALLOC set, so it's
potentially subject to this same class of issue -- though I haven't been
able to reproduce the WARN_ON_ONCE() via CIFS, since unlike xfsaild(),
cifs_demultiplex_thread() is sent SIGKILL before exiting, and that
interrupts the write to the BSD process accounting file.
Either way, leaving PF_MEMALLOC set is potentially problematic. Let's
clean this up by properly saving and restoring PF_MEMALLOC.
[1] https://lore.kernel.org/r/0000000000000e7156059f751d7b@google.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The warning we print on mount about how to use less secure dialects
(when the user does not specify a version on mount) is useful
but is noisy to print on every default mount, and can be changed
to a warn_once. Slightly updated the warning text as well to note
SMB3.1.1 which has been the default which is typically negotiated
(for a few years now) by most servers.
"No dialect specified on mount. Default has changed to a more
secure dialect, SMB2.1 or later (e.g. SMB3.1.1), from CIFS
(SMB1). To use the less secure SMB1 dialect to access old
servers which do not support SMB3.1.1 (or even SMB3 or SMB2.1)
specify vers=1.0 on mount."
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
fix warning [-Wunused-but-set-variable] at variable 'rc',
keeping the code readable.
Signed-off-by: Qiujun Huang <hqjagain@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Since commit d0677992d2 ("cifs: add support for flock") added
support for flock, LTP/flock03[1] testcase started to fail.
This testcase is testing flock lock and unlock across fork.
The parent locks file and starts the child process, in which
it unlock the same fd and lock the same file with another fd
again. All the lock and unlock operation should succeed.
Now the child process does not actually unlock the file, so
the following lock fails. Fix this by allowing flock and OFD
lock go through the unlock routine, not skipping if the unlock
request comes from another process.
Patch has been tested by LTP/xfstests on samba and Windows
server, v3.11, with or without cache=none mount option.
[1] https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/syscalls/flock/flock03.c
Signed-off-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
See commit 349457ccf2
"Allow file systems to manually d_move() inside of ->rename()"
Lessens possibility of race conditions in rename
Signed-off-by: Steve French <stfrench@microsoft.com>
allows SMB2_open() callers to pass down a POSIX data buffer that will
trigger requesting POSIX create context and parsing the response into
the provided buffer.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
* add code to request POSIX info level
* parse dir entries and fill cifs_fattr to get correct inode data
since the POSIX payload is variable size the number of entries in a
FIND response needs to be computed differently.
Dirs and regular files are properly reported along with mode bits,
hardlink number, c/m/atime. No special files yet (see below).
Current experimental version of Samba with the extension unfortunately
has issues with wildcards and needs the following patch:
> --- i/source3/smbd/smb2_query_directory.c
> +++ w/source3/smbd/smb2_query_directory.c
> @@ -397,9 +397,7 @@ smbd_smb2_query_directory_send(TALLOC_CTX
> *mem_ctx,
> }
> }
>
> - if (!state->smbreq->posix_pathnames) {
> wcard_has_wild = ms_has_wild(state->in_file_name);
> - }
>
> /* Ensure we've canonicalized any search path if not a wildcard. */
> if (!wcard_has_wild) {
>
Also for special files despite reporting them as reparse point samba
doesn't set the reparse tag field. This patch will mark them as needing
re-evaluation but the re-evaluate code doesn't deal with it yet.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
* add new info level and structs for SMB2 posix extension
* add functions to parse and validate it
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
