For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.
So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.
Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().
Here's an example of how to trigger that:
$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard
(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 0.0 0.0 12892 1008 pts/0 S 12:24 0:00 stat -f
/mnt/test
$ kill -9 2511
(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 2511 83.2 0.0 12892 1008 pts/0 R 12:24 30:01 stat -f
/mnt/test
By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch fixes a memory leak when doing a setxattr(2) in SMB2+.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
SMB1 mounting broke in commit 35e2cc1ba7
("cifs: Use correct packet length in SMB2_TRANSFORM header")
Fix it and also rename smb2_rqst_len to smb_rqst_len
to make it less unobvious that the function is also called from
CIFS/SMB1
Good job by Paulo reviewing and cleaning up Ronnie's original patch.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes: c713c8770f ("cifs: push rfc1002 generation down the stack")
We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.
Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fixes: c713c8770f ("cifs: push rfc1002 generation down the stack")
We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.
Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
With protocol version 2.0 mounts we have seen crashes with corrupt mid
entries. Either the server->pending_mid_q list becomes corrupt with a
cyclic reference in one element or a mid object fetched by the
demultiplexer thread becomes overwritten during use.
Code review identified a race between the demultiplexer thread and the
request issuing thread. The demultiplexer thread seems to be written
with the assumption that it is the sole user of the mid object until
it calls the mid callback which either wakes the issuer task or
deletes the mid.
This assumption is not true because the issuer task can be woken up
earlier by a signal. If the demultiplexer thread has proceeded as far
as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer
thread will happily end up calling cifs_delete_mid while the
demultiplexer thread still is using the mid object.
Inserting a delay in the cifs demultiplexer thread widens the race
window and makes reproduction of the race very easy:
if (server->large_buf)
buf = server->bigbuf;
+ usleep_range(500, 4000);
server->lstrp = jiffies;
To resolve this I think the proper solution involves putting a
reference count on the mid object. This patch makes sure that the
demultiplexer thread holds a reference until it has finished
processing the transaction.
Cc: stable@vger.kernel.org
Signed-off-by: Lars Persson <larper@axis.com>
Acked-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The following check would never evaluate to true:
> if (i == 0 && iov[0].iov_len <= 4)
Because 'i' always starts at 1.
This patch fixes it and also move the header checks outside the for loop
- which makes more sense.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
In smb3_init_transform_rq(), 'orig_len' was only counting the request
length, but forgot to count any data pages in the request.
Writing or creating files with the 'seal' mount option was broken.
In addition, do some code refactoring by exporting smb2_rqst_len() to
calculate the appropriate packet size and avoid duplicating the same
calculation all over the code.
The start of the io vector is either the rfc1002 length (4 bytes) or a
SMB2 header which is always > 4. Use this fact to check and skip the
rfc1002 length if requested.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If server does not support listing interfaces then do not
display empty "Server interfaces" line to avoid confusing users.
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Aurelien Aptel <aaptel@suse.com>
Since the rfc1002 generation was moved down to __smb_send_rqst(),
the transform header is now in rqst->rq_iov[0].
Correctly assign the transform header pointer in crypt_message().
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Now that we have the plumbing to pass request without an rfc1002
header all the way down to the point we write to the socket we no
longer need the smb2_send_recv() function.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Move the generation of the 4 byte length field down the stack and
generate it immediately before we start writing the data to the socket.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Compared to other clients the Linux smb3 client ramps up
credits very slowly, taking more than 128 operations before a
maximum size write could be sent (since the number of credits
requested is only 2 per small operation, causing the credit
limit to grow very slowly).
This lack of credits initially would impact large i/o performance,
when large i/o is tried early before enough credits are built up.
Signed-off-by: Steve French <stfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Use a read lease for the cached root fid so that we can detect
when the content of the directory changes (via a break) at which time
we close the handle. On next access to the root the handle will be reopened
and cached again.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
There were no conflicts between this and the contents of linux-next
until just before the merge window, when we saw multiple problems:
- A minor conflict with my own y2038 fixes, which I could address
by adding another patch on top here.
- One semantic conflict with late changes to the NFS tree. I addressed
this by merging Deepa's original branch on top of the changes that
now got merged into mainline and making sure the merge commit includes
the necessary changes as produced by coccinelle.
- A trivial conflict against the removal of staging/lustre.
- Multiple conflicts against the VFS changes in the overlayfs tree.
These are still part of linux-next, but apparently this is no longer
intended for 4.18 [1], so I am ignoring that part.
As Deepa writes:
The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64 timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual
replacement becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions.
Thomas Gleixner adds:
I think there is no point to drag that out for the next merge window.
The whole thing needs to be done in one go for the core changes which
means that you're going to play that catchup game forever. Let's get
over with it towards the end of the merge window.
[1] https://www.spinics.net/lists/linux-fsdevel/msg128294.html
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Merge tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground
Pull inode timestamps conversion to timespec64 from Arnd Bergmann:
"This is a late set of changes from Deepa Dinamani doing an automated
treewide conversion of the inode and iattr structures from 'timespec'
to 'timespec64', to push the conversion from the VFS layer into the
individual file systems.
As Deepa writes:
'The series aims to switch vfs timestamps to use struct timespec64.
Currently vfs uses struct timespec, which is not y2038 safe.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64
timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual replacement
becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions'
Thomas Gleixner adds:
'I think there is no point to drag that out for the next merge
window. The whole thing needs to be done in one go for the core
changes which means that you're going to play that catchup game
forever. Let's get over with it towards the end of the merge window'"
* tag 'vfs-timespec64' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
pstore: Remove bogus format string definition
vfs: change inode times to use struct timespec64
pstore: Convert internal records to timespec64
udf: Simplify calls to udf_disk_stamp_to_time
fs: nfs: get rid of memcpys for inode times
ceph: make inode time prints to be long long
lustre: Use long long type to print inode time
fs: add timespec64_truncate()
Pull the timespec64 conversion from Deepa Dinamani:
"The series aims to switch vfs timestamps to use
struct timespec64. Currently vfs uses struct timespec,
which is not y2038 safe.
The flag patch applies cleanly. I've not seen the timestamps
update logic change often. The series applies cleanly on 4.17-rc6
and linux-next tip (top commit: next-20180517).
I'm not sure how to merge this kind of a series with a flag patch.
We are targeting 4.18 for this.
Let me know if you have other suggestions.
The series involves the following:
1. Add vfs helper functions for supporting struct timepec64 timestamps.
2. Cast prints of vfs timestamps to avoid warnings after the switch.
3. Simplify code using vfs timestamps so that the actual
replacement becomes easy.
4. Convert vfs timestamps to use struct timespec64 using a script.
This is a flag day patch.
I've tried to keep the conversions with the script simple, to
aid in the reviews. I've kept all the internal filesystem data
structures and function signatures the same.
Next steps:
1. Convert APIs that can handle timespec64, instead of converting
timestamps at the boundaries.
2. Update internal data structures to avoid timestamp conversions."
I've pulled it into a branch based on top of the NFS changes that
are now in mainline, so I could resolve the non-obvious conflict
between the two while merging.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This leak was introduced in 91cb74f514 and caused us
to leak one small buffer for every symlink query.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
if mounting as smb3 do not allow cifs (vers=1.0) or insecure vers=2.0
mounts.
For example:
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1
root@smf-Thinkpad-P51:~/cifs-2.6# umount /mnt
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1,vers=1.0
mount: /mnt: wrong fs type, bad option, bad superblock on //127.0.0.1/scratch ...
root@smf-Thinkpad-P51:~/cifs-2.6# dmesg | grep smb3
[ 4302.200122] CIFS VFS: vers=1.0 (cifs) not permitted when mounting with smb3
root@smf-Thinkpad-P51:~/cifs-2.6# mount -t smb3 //127.0.0.1/scratch /mnt -o username=testuser,password=Testpass1,vers=3.11
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Sachin Prabhu <sprabhu@redhat.com>
cifs->master_tlink is NULL against Win Server 2016 (which is
strange.. not sure why) and is dereferenced in cifs_sb_master_tcon().
move master_tlink getter to cifsglob.h so it can be used from
smb2misc.c
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
The smb2 hdr is now in iov 1
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Encryption function needs to read data starting page offset from input
buffer.
This doesn't affect decryption path since it allocates its own page
buffers.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When calculating signature for the packet, it needs to read into the
correct page offset for the data.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Change code to pass the correct page offset during memory registration for
RDMA read/write.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
RDMA recv function needs to place data to the correct place starting at
page offset.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The RDMA send function needs to look at offset in the request pages, and
send data starting from there.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It's possible that the offset is non-zero in the page to send, change the
function to pass this offset to socket.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Introduce a function rqst_page_get_length to return the page offset and
length for a given page in smb_rqst. This function is to be used by
following patches.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It's possible that the page offset is non-zero in the pages in a request,
change the function to calculate the correct data buffer length.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Validate_buf () function checks for an expected minimum sized response
passed to query_info() function.
For security information, the size of a security descriptor can be
smaller (one subauthority, no ACEs) than the size of the structure
that defines FileInfoClass of FileAllInformation.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199725
Cc: <stable@vger.kernel.org>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Noah Morrison <noah.morrison@rubrik.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It seems Ronnie's preamble removal broke signing.
the signing functions are called when:
A) we send a request (to sign it)
B) when we recv a response (to check the signature).
On code path A, the smb2 header is in iov[1] but on code path B, the
smb2 header is in iov[0] (and there's only one vector).
So we have different iov indexes for the smb2 header but the signing
function always use index 1. Fix this by checking the nb of io vectors
in the signing function as a hint.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag '4.18-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs updates from Steve French:
- smb3 fixes for stable
- addition of ftrace hooks for cifs.ko
- improvements in compounding and smbdirect (rdma)
* tag '4.18-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (38 commits)
CIFS: Add support for direct pages in wdata
CIFS: Use offset when reading pages
CIFS: Add support for direct pages in rdata
cifs: update multiplex loop to handle compounded responses
cifs: remove header_preamble_size where it is always 0
cifs: remove struct smb2_hdr
CIFS: 511c54a2f6 adds a check for session expiry, status STATUS_NETWORK_SESSION_EXPIRED, however the server can also respond with STATUS_USER_SESSION_DELETED in cases where the session has been idle for some time and the server reaps the session to recover resources.
cifs: change smb2_get_data_area_len to take a smb2_sync_hdr as argument
cifs: update smb2_calc_size to use smb2_sync_hdr instead of smb2_hdr
cifs: remove struct smb2_oplock_break_rsp
cifs: remove rfc1002 header from all SMB2 response structures
smb3: on reconnect set PreviousSessionId field
smb3: Add posix create context for smb3.11 posix mounts
smb3: add tracepoints for smb2/smb3 open
cifs: add debug output to show nocase mount option
smb3: add define for id for posix create context and corresponding struct
cifs: update smb2_check_message to handle PDUs without a 4 byte length header
smb3: allow "posix" mount option to enable new SMB311 protocol extensions
smb3: add support for posix negotiate context
cifs: allow disabling less secure legacy dialects
...
Pull dcache lookup cleanups from Al Viro:
"Cleaning ->lookup() instances up - mostly d_splice_alias() conversions"
* 'work.lookup' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (29 commits)
switch the rest of procfs lookups to d_splice_alias()
procfs: switch instantiate_t to d_splice_alias()
don't bother with tid_fd_revalidate() in lookups
proc_lookupfd_common(): don't bother with instantiate unless the file is open
procfs: get rid of ancient BS in pid_revalidate() uses
cifs_lookup(): switch to d_splice_alias()
cifs_lookup(): cifs_get_inode_...() never returns 0 with *inode left NULL
9p: unify paths in v9fs_vfs_lookup()
ncp_lookup(): use d_splice_alias()
hfsplus: switch to d_splice_alias()
hfs: don't allow mounting over .../rsrc
hfs: use d_splice_alias()
omfs_lookup(): report IO errors, use d_splice_alias()
orangefs_lookup: simplify
openpromfs: switch to d_splice_alias()
xfs_vn_lookup: simplify a bit
adfs_lookup: do not fail with ENOENT on negatives, use d_splice_alias()
adfs_lookup_byname: .. *is* taken care of in fs/namei.c
romfs_lookup: switch to d_splice_alias()
qnx6_lookup: switch to d_splice_alias()
...
Add a function to allocate wdata without allocating pages for data
transfer. This gives the caller an option to pass a number of pages that
point to the data buffer to write to.
wdata is reponsible for free those pages after it's done.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
With offset defined in rdata, transport functions need to look at this
offset when reading data into the correct places in pages.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
