+ Define the generic netlink family commands and message attributes to
communicate with the userspace daemon
+ The register and unregister commands are sent when connecting or
disconnecting a tree. The witness registration keeps a pointer to
the tcon and has the same lifetime.
+ Each registration has an id allocated by an IDR. This id is sent to the
userspace daemon in the register command, and will be included in the
notification messages from the userspace daemon to retrieve from the
IDR the matching registration.
+ The authentication information is bundled in the register message.
If kerberos is used the message just carries a flag.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add 'witness' mount option to register for witness notifications.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Move the function to misc.c and give it a public header.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
as we now have a full smb3_fs_context as part of the cifs superblock
we no longer need a local copy of the mount options and can just
reference the copy in the smb3_fs_context.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
and populate it during mount in cifs_smb3_do_mount()
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
none of the callers use this argument any more.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
See Documentation/filesystems/mount_api.rst for details on new mount API
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
No change to logic, just moving the enum of cifs mount parms into a header
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Harmonize and change all such variables to 'ctx', where possible.
No changes to actual logic.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In some scenarios (DFS and BAD_NETWORK_NAME) set_root_set() can be
called with a NULL ses->tcon_ipc.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch fixes a potential use-after-free bug in
cifs_echo_request().
For instance,
thread 1
--------
cifs_demultiplex_thread()
clean_demultiplex_info()
kfree(server)
thread 2 (workqueue)
--------
apic_timer_interrupt()
smp_apic_timer_interrupt()
irq_exit()
__do_softirq()
run_timer_softirq()
call_timer_fn()
cifs_echo_request() <- use-after-free in server ptr
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This and related patches which move mount related
code to fs_context.c has the advantage of
shriking the code in fs/cifs/connect.c (which had
the second most lines of code of any of the files
in cifs.ko and was getting harder to read due
to its size) and will also make it easier to
switch over to the new mount API in the future.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Helps to shrink connect.c and make it more readable
by moving mount related code to fs_context.c and
fs_context.h
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
This patch moves the parsing of security mount options into
fs_context.ch. There are no changes to any logic.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
To servers which do not support directory leases (e.g. Samba)
it is wasteful to try to open_shroot (ie attempt to cache the
root directory handle). Skip attempt to open_shroot when
server does not indicate support for directory leases.
Cuts the number of requests on mount from 17 to 15, and
cuts the number of requests on stat of the root directory
from 4 to 3.
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org> # v5.1+
Can be helpful in debugging mount and reconnect issues
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently STATUS_IO_TIMEOUT is not treated as retriable error.
It is currently mapped to ETIMEDOUT and returned to userspace
for most system calls. STATUS_IO_TIMEOUT is returned by server
in case of unavailability or throttling errors.
This patch will map the STATUS_IO_TIMEOUT to EAGAIN, so that it
can be retried. Also, added a check to drop the connection to
not overload the server in case of ongoing unavailability.
Signed-off-by: Rohith Surabattula <rohiths@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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Merge tag '5.9-rc2-smb-fix' of git://git.samba.org/sfrench/cifs-2.6
Pull cfis fix from Steve French:
"DFS fix for referral problem when using SMB1"
* tag '5.9-rc2-smb-fix' of git://git.samba.org/sfrench/cifs-2.6:
cifs: fix check of tcon dfs in smb1
For SMB1, the DFS flag should be checked against tcon->Flags rather
than tcon->share_flags. While at it, add an is_tcon_dfs() helper to
check for DFS capability in a more generic way.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
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Merge tag '5.9-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Three small cifs/smb3 fixes, one for stable fixing mkdir path with
the 'idsfromsid' mount option"
* tag '5.9-rc-smb3-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6:
SMB3: Fix mkdir when idsfromsid configured on mount
cifs: Convert to use the fallthrough macro
cifs: Fix an error pointer dereference in cifs_mount()
Merge misc updates from Andrew Morton:
- a few MM hotfixes
- kthread, tools, scripts, ntfs and ocfs2
- some of MM
Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
mm: vmscan: consistent update to pgrefill
mm/vmscan.c: fix typo
khugepaged: khugepaged_test_exit() check mmget_still_valid()
khugepaged: retract_page_tables() remember to test exit
khugepaged: collapse_pte_mapped_thp() protect the pmd lock
khugepaged: collapse_pte_mapped_thp() flush the right range
mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
mm: thp: replace HTTP links with HTTPS ones
mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
mm/page_alloc.c: skip setting nodemask when we are in interrupt
mm/page_alloc: fallbacks at most has 3 elements
mm/page_alloc: silence a KASAN false positive
mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
mm/page_alloc.c: simplify pageblock bitmap access
mm/page_alloc.c: extract the common part in pfn_to_bitidx()
mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
mm/shuffle: remove dynamic reconfiguration
mm/memory_hotplug: document why shuffle_zone() is relevant
mm/page_alloc: remove nr_free_pagecache_pages()
mm: remove vm_total_pages
...
As said by Linus:
A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.
In "kzalloc()", the z is meaningful and an important part of what the
caller wants.
In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.
The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.
Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.
The renaming is done by using the command sequence:
git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'
followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.
[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]
Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The error handling calls kfree(full_path) so we can't let it be a NULL
pointer. There used to be a NULL assignment here but we accidentally
deleted it. Add it back.
Fixes: 7efd081582 ("cifs: document and cleanup dfs mount")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
cifs_mount() for DFS mounts is for a long time way too complex to
follow, mostly because it lacks some documentation, does a lot of
operations like resolving DFS roots and links, checking for path
components, perform failover, crap code, etc.
Besides adding some documentation to it, do some cleanup and ensure
that the following is implemented and supported:
* non-DFS mounts
* DFS failover
* DFS root mounts
- tcon and cifs_sb must contain DFS path (NOT including prefix)
- if prefix path, then save it in cifs_sb and it must not be
changed
* DFS link mounts
- tcon and cifs_sb must contain DFS path (including prefix)
- if prefix path, then save it in cifs_sb and it may be changed
* prevent recursion on broken link referrals (MAX_NESTED_LINKS)
* check every path component of the currently resolved
target (including prefix), and chase them accordingly
* make sure that DFS referrals go through newly resolved root
servers
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For DFS root mounts that contain a prefix path, do not change them
after failover.
E.g., if the user mounts
//srvA/root/dir1
and then lost connection to srvA, it will reconnect to
//srvB/root/dir1
In case of DFS links, which may resolve to different prefix paths
depending on their list of targets, the following must be supported:
- mount //srvA/root/link/bar
- connect to //srvA/share
- set prefix path to "bar"
- lost connection to srvA
- reconnect to next target: //srvB/share/foo
- set new prefix path to "foo/bar"
In cifs_tree_connect(), check the server_type field of the cached DFS
referral to determine whether or not prefix path should be updated.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently if the call dfs_cache_get_tgt_share fails we cannot
fully guarantee that share and prefix are set to NULL and the
next iteration of the loop can end up potentially double freeing
these pointers. Since the semantics of dfs_cache_get_tgt_share
are ambiguous for failure cases with the setting of share and
prefix (currently now and the possibly the future), it seems
prudent to set the pointers to NULL when the objects are
free'd to avoid any double frees.
Addresses-Coverity: ("Double free")
Fixes: 96296c946a2a ("cifs: handle RESP_GET_DFS_REFERRAL.PathConsumed in reconnect")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Use PathConsumed field when parsing prefixes of referral paths that
either match a cache entry or are a complete prefix path of an
existing entry.
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 case there were no cached DFS referrals in
reconn_setup_dfs_targets(), set cifs_sb to NULL prior to calling
reconn_set_next_dfs_target() so it would not try to access an empty
tgt_list.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This function has nothing to do with *invalidation* but setting up the
next target server from a cached referral.
Rename it to reconn_set_next_dfs_target(). While at it, get rid of
some meaningless checks.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
They were identical execpt to CIFSTCon() vs. SMB2_tcon().
These are also available via ops->tree_connect().
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Convert cpu_to_be32(be32_to_cpu(E1) + E2) to use be32_add_cpu().
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The flag from the primary tcon needs to be copied into the volume info
so that cifs_get_tcon will try to enable extensions on the per-user
tcon. At that point, since posix extensions must have already been
enabled on the superblock, don't try to needlessly adjust the mount
flags.
Fixes: ce558b0e17 ("smb3: Add posix create context for smb3.11 posix mounts")
Fixes: b326614ea2 ("smb3: allow "posix" mount option to enable new SMB311 protocol extensions")
Signed-off-by: Paul Aurich <paul@darkrain42.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Fixes: ca567eb2b3 ("SMB3: Allow persistent handle timeout to be configurable on mount")
Signed-off-by: Paul Aurich <paul@darkrain42.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Without this:
- persistent handles will only be enabled for per-user tcons if the
server advertises the 'Continuous Availabity' capability
- resilient handles would never be enabled for per-user tcons
Signed-off-by: Paul Aurich <paul@darkrain42.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Ensure multiuser SMB3 mounts use encryption for all users' tcons if the
mount options are configured to require encryption. Without this, only
the primary tcon and IPC tcons are guaranteed to be encrypted. Per-user
tcons would only be encrypted if the server was configured to require
encryption.
Signed-off-by: Paul Aurich <paul@darkrain42.org>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
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Merge tag '5.8-rc-smb3-fixes-part-1' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs updates from Steve French:
"22 changesets, 2 for stable.
Includes big performance improvement for large i/o when using
multichannel, also includes DFS fixes"
* tag '5.8-rc-smb3-fixes-part-1' of git://git.samba.org/sfrench/cifs-2.6: (22 commits)
cifs: update internal module version number
cifs: multichannel: try to rebind when reconnecting a channel
cifs: multichannel: use pointer for binding channel
smb3: remove static checker warning
cifs: multichannel: move channel selection above transport layer
cifs: multichannel: always zero struct cifs_io_parms
cifs: dump Security Type info in DebugData
smb3: fix incorrect number of credits when ioctl MaxOutputResponse > 64K
smb3: default to minimum of two channels when multichannel specified
cifs: multichannel: move channel selection in function
cifs: fix minor typos in comments and log messages
smb3: minor update to compression header definitions
cifs: minor fix to two debug messages
cifs: Standardize logging output
smb3: Add new parm "nodelete"
cifs: move some variables off the stack in smb2_ioctl_query_info
cifs: reduce stack use in smb2_compound_op
cifs: get rid of unused parameter in reconn_setup_dfs_targets()
cifs: handle hostnames that resolve to same ip in failover
cifs: set up next DFS target before generic_ip_connect()
...
When "multichannel" is specified on mount, make sure to default to
at least two channels.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
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>
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 "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>
Add a helper to directly set the TCP_NODELAY sockopt from kernel space
without going through a fake uaccess. Cleanup the callers to avoid
pointless wrappers now that this is a simple function call.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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 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>
We really, really don't want people using insecure dialects
unless they realize what they are doing ...
Add mount warning if mounting with vers=1.0 (older SMB1/CIFS
dialect) instead of the default (SMB2.1 or later, typically
SMB3.1.1).
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
This means it's consistently called and the callers don't need to
care about it.
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For the case where we have a DFS path like below and we're currently
connected to targetA:
//dfsroot/link -> //targetA/share/foo, //targetB/share/bar
after failover, we should make sure to update cifs_sb->prepath so the
next operations will use the new prefix path "/bar".
Besides, in order to simplify the use of different prefix paths,
enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to
revalidate the root dentry every time we set a new prefix path.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
A number of the debug statements output file or directory mode
in hex. Change these to print using octal.
Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When "backup intent" is requested on the mount (e.g. backupuid or
backupgid mount options), the corresponding flag was missing from
some of the operations.
Change all operations to use the macro cifs_create_options() to
set the backup intent flag if needed.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
RHBZ: 1760879
Fix an oops in match_prepath() by making sure that the prepath string is not
NULL before we pass it into strcmp().
This is similar to other checks we make for example in cifs_root_iget()
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
With the addition of SMB session channels, we introduced new TCP
server pointers that have no sessions or tcons associated with them.
In this case, when we started looking for TCP connections, we might
end up picking session channel rather than the master connection,
hence failing to get either a session or a tcon.
In order to fix that, this patch introduces a new "is_channel" field
to TCP_Server_Info structure so we can skip session channels during
lookup of connections.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
After doing mount() successfully we call cifs_try_adding_channels()
which will open as many channels as it can.
Channels are closed when the master session is closed.
The master connection becomes the first channel.
,-------------> global cifs_tcp_ses_list <-------------------------.
| |
'- TCP_Server_Info <--> TCP_Server_Info <--> TCP_Server_Info <-'
(master con) (chan#1 con) (chan#2 con)
| ^ ^ ^
v '--------------------|--------------------'
cifs_ses |
- chan_count = 3 |
- chans[] ---------------------'
- smb3signingkey[]
(master signing key)
Note how channel connections don't have sessions. That's because
cifs_ses can only be part of one linked list (list_head are internal
to the elements).
For signing keys, each channel has its own signing key which must be
used only after the channel has been bound. While it's binding it must
use the master session signing key.
For encryption keys, since channel connections do not have sessions
attached we must now find matching session by looping over all sessions
in smb2_get_enc_key().
Each channel is opened like a regular server connection but at the
session setup request step it must set the
SMB2_SESSION_REQ_FLAG_BINDING flag and use the session id to bind to.
Finally, while sending in compound_send_recv() for requests that
aren't negprot, ses-setup or binding related, use a channel by cycling
through the available ones (round-robin).
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently a lot of the code to initialize a connection & session uses
the cifs_ses as input. But depending on if we are opening a new session
or a new channel we need to use different server pointers.
Add a "binding" flag in cifs_ses and a helper function that returns
the server ptr a session should use (only in the sess establishment
code path).
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
adds:
- [no]multichannel to enable/disable multichannel
- max_channels=N to control how many channels to create
these options are then stored in the volume struct.
- store channels and max_channels in cifs_ses
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When an OPEN command is cancelled we mark a mid as
cancelled and let the demultiplex thread process it
by closing an open handle. The problem is there is
a race between a system call thread and the demultiplex
thread and there may be a situation when the mid has
been already processed before it is set as cancelled.
Fix this by processing cancelled requests when mids
are being destroyed which means that there is only
one thread referencing a particular mid. Also set
mids as cancelled unconditionally on their state.
Cc: Stable <stable@vger.kernel.org>
Tested-by: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
There is a race between a system call processing thread
and the demultiplex thread when mid->resp_buf becomes NULL
and later is being accessed to get credits. It happens when
the 1st thread wakes up before a mid callback is called in
the 2nd one but the mid state has already been set to
MID_RESPONSE_RECEIVED. This causes NULL pointer dereference
in mid callback.
Fix this by saving credits from the response before we
update the mid state and then use this value in the mid
callback rather then accessing a response buffer.
Cc: Stable <stable@vger.kernel.org>
Fixes: ee258d7915 ("CIFS: Move credit processing to mid callbacks for SMB3")
Tested-by: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
When the client hits reconnect it iterates over the mid
pending queue marking entries for retry and moving them
to a temporary list to issue callbacks later without holding
GlobalMid_Lock. In the same time there is no guarantee that
mids can't be removed from the temporary list or even
freed completely by another thread. It may cause a temporary
list corruption:
[ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469
[ 430.464668] ------------[ cut here ]------------
[ 430.466569] kernel BUG at lib/list_debug.c:51!
[ 430.468476] invalid opcode: 0000 [#1] SMP PTI
[ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19
[ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55
...
[ 430.510426] Call Trace:
[ 430.511500] cifs_reconnect+0x25e/0x610 [cifs]
[ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs]
[ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs]
[ 430.517452] ? try_to_wake_up+0x212/0x650
[ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs]
[ 430.521086] ? allocate_buffers+0x66/0x120 [cifs]
[ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs]
[ 430.525116] kthread+0xfb/0x130
[ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs]
[ 430.528514] ? kthread_park+0x90/0x90
[ 430.530019] ret_from_fork+0x35/0x40
Fix this by obtaining extra references for mids being retried
and marking them as MID_DELETED which indicates that such a mid
has been dequeued from the pending list.
Also move mid cleanup logic from DeleteMidQEntry to
_cifs_mid_q_entry_release which is called when the last reference
to a particular mid is put. This allows to avoid any use-after-free
of response buffers.
The patch needs to be backported to stable kernels. A stable tag
is not mentioned below because the patch doesn't apply cleanly
to any actively maintained stable kernel.
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We only want to avoid blocking in connect when mounting SMB root
filesystems, otherwise bail out from generic_ip_connect() so cifs.ko
can perform any reconnect failover appropriately.
This fixes DFS failover/reconnection tests in upstream buildbot.
Fixes: 8eecd1c2e5 ("cifs: Add support for root file systems")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Message was intended only for developer temporary build
In addition cleanup two minor warnings noticed by Coverity
and a trivial change to workaround a sparse warning
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Now that sparse has been fixed, it spotted a couple recent minor
endian errors (and removed one additional sparse warning).
Thanks to Luc Van Oostenryck for his help fixing sparse.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Introduce a new CONFIG_CIFS_ROOT option to handle root file systems
over a SMB share.
In order to mount the root file system during the init process, make
cifs.ko perform non-blocking socket operations while mounting and
accessing it.
Cc: Steve French <smfrench@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: Steve French <stfrench@microsoft.com>
In some cases to work around server bugs or performance
problems it can be helpful to be able to disable requesting
SMB2.1/SMB3 leases on a particular mount (not to all servers
and all shares we are mounted to). Add new mount parm
"nolease" which turns off requesting leases on directory
or file opens. Currently the only way to disable leases is
globally through a module load parameter. This is more
granular.
Suggested-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Displayed in /proc/fs/cifs/Stats once for each
socket we are connected to.
This allows us to find out what the maximum number of
requests that had been in flight (at any one time). Note that
/proc/fs/cifs/Stats can be reset if you want to look for
maximum over a small period of time.
Sample output (immediately after mount):
Resources in use
CIFS Session: 1
Share (unique mount targets): 2
SMB Request/Response Buffer: 1 Pool size: 5
SMB Small Req/Resp Buffer: 1 Pool size: 30
Operations (MIDs): 0
0 session 0 share reconnects
Total vfs operations: 5 maximum at one time: 2
Max requests in flight: 2
1) \\localhost\scratch
SMBs: 18
Bytes read: 0 Bytes written: 0
...
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Disable offload of the decryption of encrypted read responses
by default (equivalent to setting this new mount option "esize=0").
Allow setting the minimum encrypted read response size that we
will choose to offload to a worker thread - it is now configurable
via on a new mount option "esize="
Depending on which encryption mechanism (GCM vs. CCM) and
the number of reads that will be issued in parallel and the
performance of the network and CPU on the client, it may make
sense to enable this since it can provide substantial benefit when
multiple large reads are in flight at the same time.
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Add new mount option "signloosely" which enables signing but skips the
sometimes expensive signing checks in the responses (signatures are
calculated and sent correctly in the SMB2/SMB3 requests even with this
mount option but skipped in the responses). Although weaker for security
(and also data integrity in case a packet were corrupted), this can provide
enough of a performance benefit (calculating the signature to verify a
packet can be expensive especially for large packets) to be useful in
some cases.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
If the server config (e.g. Samba smb.conf "csc policy = disable)
for the share indicates that the share should not be cached, log
a warning message if forced client side caching ("cache=ro" or
"cache=singleclient") is requested on mount.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
If a share is known to be only to be accessed by one client, we
can aggressively cache writes not just reads to it.
Add "cache=" option (cache=singleclient) for mounting read write shares
(that will not be read or written to from other clients while we have
it mounted) in order to improve performance.
Signed-off-by: Steve French <stfrench@microsoft.com>
Add some additional logging so the user can see if the share they
mounted with cache=ro is considered read only by the server
CIFS: Attempting to mount //localhost/test
CIFS VFS: mounting share with read only caching. Ensure that the share will not be modified while in use.
CIFS VFS: read only mount of RW share
CIFS: Attempting to mount //localhost/test-ro
CIFS VFS: mounting share with read only caching. Ensure that the share will not be modified while in use.
CIFS VFS: mounted to read only share
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
If a share is immutable (at least for the period that it will
be mounted) it would be helpful to not have to revalidate
dentries repeatedly that we know can not be changed remotely.
Add "cache=" option (cache=ro) for mounting read only shares
in order to improve performance in cases in which we know that
the share will not be changing while it is in use.
Signed-off-by: Steve French <stfrench@microsoft.com>
which can be used from contexts where we have a TCP_Server_Info *server.
This new macro will prepend the debugging string with "Server:<servername> "
which will help when debugging issues on hosts with many cifs connections
to several different servers.
Convert a bunch of cifs_dbg(VFS) calls to cifs_server_dbg(VFS)
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Using strscpy is cleaner, and avoids some problems with
handling maximum length strings. Linus noticed the
original problem and Aurelien pointed out some additional
problems. Fortunately most of this is SMB1 code (and
in particular the ASCII string handling older, which
is less common).
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It's safer to zero out the password so that it can never be disclosed.
Fixes: 0c219f5799c7 ("cifs: set domainName when a domain-key is used in multiuser")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
RHBZ: 1710429
When we use a domain-key to authenticate using multiuser we must also set
the domainnmame for the new volume as it will be used and passed to the server
in the NTLMSSP Domain-name.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd. I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN. So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.
Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig. As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL. Which after the first signal will allow userspace
to send signals to these kernel threads. At least for
wake_ack_receiver in drbd that does not appear actively wrong.
So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.
Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.
This change was partly inspired by similar cifs and drbd patches that
added allow_signal.
Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com>
Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Steve French <smfrench@gmail.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Fixes: 247bc9470b ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf0 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Fixes: 72abe3bcf0 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
The global change from force_sig caused module unloading of cifs.ko
to fail (since the cifsd process could not be killed, "rmmod cifs"
now would always fail)
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
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Merge tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs updates from Steve French:
"Fixes (three for stable) and improvements including much faster
encryption (SMB3.1.1 GCM)"
* tag '4.3-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (27 commits)
smb3: smbdirect no longer experimental
cifs: fix crash in smb2_compound_op()/smb2_set_next_command()
cifs: fix crash in cifs_dfs_do_automount
cifs: fix parsing of symbolic link error response
cifs: refactor and clean up arguments in the reparse point parsing
SMB3: query inode number on open via create context
smb3: Send netname context during negotiate protocol
smb3: do not send compression info by default
smb3: add new mount option to retrieve mode from special ACE
smb3: Allow query of symlinks stored as reparse points
cifs: Fix a race condition with cifs_echo_request
cifs: always add credits back for unsolicited PDUs
fs: cifs: cifsssmb: Change return type of convert_ace_to_cifs_ace
add some missing definitions
cifs: fix typo in debug message with struct field ia_valid
smb3: minor cleanup of compound_send_recv
CIFS: Fix module dependency
cifs: simplify code by removing CONFIG_CIFS_ACL ifdef
cifs: Fix check for matching with existing mount
cifs: Properly handle auto disabling of serverino option
...
RHBZ: 1649907
Fix a crash that happens while attempting to mount a DFS referral from the same server on the root of a filesystem.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull force_sig() argument change from Eric Biederman:
"A source of error over the years has been that force_sig has taken a
task parameter when it is only safe to use force_sig with the current
task.
The force_sig function is built for delivering synchronous signals
such as SIGSEGV where the userspace application caused a synchronous
fault (such as a page fault) and the kernel responded with a signal.
Because the name force_sig does not make this clear, and because the
force_sig takes a task parameter the function force_sig has been
abused for sending other kinds of signals over the years. Slowly those
have been fixed when the oopses have been tracked down.
This set of changes fixes the remaining abusers of force_sig and
carefully rips out the task parameter from force_sig and friends
making this kind of error almost impossible in the future"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
signal: Remove the signal number and task parameters from force_sig_info
signal: Factor force_sig_info_to_task out of force_sig_info
signal: Generate the siginfo in force_sig
signal: Move the computation of force into send_signal and correct it.
signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
signal: Remove the task parameter from force_sig_fault
signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
signal: Explicitly call force_sig_fault on current
signal/unicore32: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from ptrace_break
signal/nds32: Remove tsk parameter from send_sigtrap
signal/riscv: Remove tsk parameter from do_trap
signal/sh: Remove tsk parameter from force_sig_info_fault
signal/um: Remove task parameter from send_sigtrap
signal/x86: Remove task parameter from send_sigtrap
signal: Remove task parameter from force_sig_mceerr
signal: Remove task parameter from force_sig
signal: Remove task parameter from force_sigsegv
...
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Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull keyring ACL support from David Howells:
"This changes the permissions model used by keys and keyrings to be
based on an internal ACL by the following means:
- Replace the permissions mask internally with an ACL that contains a
list of ACEs, each with a specific subject with a permissions mask.
Potted default ACLs are available for new keys and keyrings.
ACE subjects can be macroised to indicate the UID and GID specified
on the key (which remain). Future commits will be able to add
additional subject types, such as specific UIDs or domain
tags/namespaces.
Also split a number of permissions to give finer control. Examples
include splitting the revocation permit from the change-attributes
permit, thereby allowing someone to be granted permission to revoke
a key without allowing them to change the owner; also the ability
to join a keyring is split from the ability to link to it, thereby
stopping a process accessing a keyring by joining it and thus
acquiring use of possessor permits.
- Provide a keyctl to allow the granting or denial of one or more
permits to a specific subject. Direct access to the ACL is not
granted, and the ACL cannot be viewed"
* tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Provide KEYCTL_GRANT_PERMISSION
keys: Replace uid/gid/perm permissions checking with an ACL
Since in theory a server could respond with compressed read
responses even if not requested on read request (assuming that
a compression negcontext is sent in negotiate protocol) - do
not send compression information during negotiate protocol
unless the user asks for compression explicitly (compression
is experimental), and add a mount warning that compression
is experimental.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
There is a special ACE used by some servers to allow the mode
bits to be stored. This can be especially helpful in scenarios
in which the client is trusted, and access checking on the
client vs the POSIX mode bits is sufficient.
Add mount option to allow enabling this behavior.
Follow on patch will add support for chmod and queryinfo
(stat) by retrieving the POSIX mode bits from the special
ACE, SID: S-1-5-88-3
See e.g.
https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/hh509017(v=ws.10)
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
There is a race condition with how we send (or supress and don't send)
smb echos that will cause the client to incorrectly think the
server is unresponsive and thus needs to be reconnected.
Summary of the race condition:
1) Daisy chaining scheduling creates a gap.
2) If traffic comes unfortunate shortly after
the last echo, the planned echo is suppressed.
3) Due to the gap, the next echo transmission is delayed
until after the timeout, which is set hard to twice
the echo interval.
This is fixed by changing the timeouts from 2 to three times the echo interval.
Detailed description of the bug: https://lutz.donnerhacke.de/eng/Blog/Groundhog-Day-with-SMB-remount
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
not just if CONFIG_CIFS_DEBUG2 is enabled.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix mount options comparison when serverino option is turned off later
in cifs_autodisable_serverino() and thus avoiding mismatch of new cifs
mounts.
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilove@microsoft.com>
When using multidialect negotiate (default or specifying vers=3.0 which
allows any smb3 dialect), fix how we check for an existing server session.
Before this fix if you mounted a second time to the same server (e.g. a
different share on the same server) we would only reuse the existing smb
session if a single dialect were requested (e.g. specifying vers=2.1 or vers=3.0
or vers=3.1.1 on the mount command). If a default mount (e.g. not
specifying vers=) is done then would always create a new socket connection
and SMB3 (or SMB3.1.1) session each time we connect to a different share
on the same server rather than reusing the existing one.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split. This will also allow a
greater range of subjects to represented.
============
WHY DO THIS?
============
The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.
For SETATTR, this includes actions that are about controlling access to a
key:
(1) Changing a key's ownership.
(2) Changing a key's security information.
(3) Setting a keyring's restriction.
And actions that are about managing a key's lifetime:
(4) Setting an expiry time.
(5) Revoking a key.
and (proposed) managing a key as part of a cache:
(6) Invalidating a key.
Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.
Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission. It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.
As for SEARCH permission, that currently covers:
(1) Finding keys in a keyring tree during a search.
(2) Permitting keyrings to be joined.
(3) Invalidation.
But these don't really belong together either, since these actions really
need to be controlled separately.
Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.
===============
WHAT IS CHANGED
===============
The SETATTR permission is split to create two new permissions:
(1) SET_SECURITY - which allows the key's owner, group and ACL to be
changed and a restriction to be placed on a keyring.
(2) REVOKE - which allows a key to be revoked.
The SEARCH permission is split to create:
(1) SEARCH - which allows a keyring to be search and a key to be found.
(2) JOIN - which allows a keyring to be joined as a session keyring.
(3) INVAL - which allows a key to be invalidated.
The WRITE permission is also split to create:
(1) WRITE - which allows a key's content to be altered and links to be
added, removed and replaced in a keyring.
(2) CLEAR - which allows a keyring to be cleared completely. This is
split out to make it possible to give just this to an administrator.
(3) REVOKE - see above.
Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together. An ACE specifies a subject, such as:
(*) Possessor - permitted to anyone who 'possesses' a key
(*) Owner - permitted to the key owner
(*) Group - permitted to the key group
(*) Everyone - permitted to everyone
Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.
Further subjects may be made available by later patches.
The ACE also specifies a permissions mask. The set of permissions is now:
VIEW Can view the key metadata
READ Can read the key content
WRITE Can update/modify the key content
SEARCH Can find the key by searching/requesting
LINK Can make a link to the key
SET_SECURITY Can change owner, ACL, expiry
INVAL Can invalidate
REVOKE Can revoke
JOIN Can join this keyring
CLEAR Can clear this keyring
The KEYCTL_SETPERM function is then deprecated.
The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.
The KEYCTL_INVALIDATE function then requires INVAL.
The KEYCTL_REVOKE function then requires REVOKE.
The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.
The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.
======================
BACKWARD COMPATIBILITY
======================
To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.
It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.
SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned
on if a keyring is being altered.
The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.
It will make the following mappings:
(1) INVAL, JOIN -> SEARCH
(2) SET_SECURITY -> SETATTR
(3) REVOKE -> WRITE if SETATTR isn't already set
(4) CLEAR -> WRITE
Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.
=======
TESTING
=======
This passes the keyutils testsuite for all but a couple of tests:
(1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
if the type doesn't have ->read(). You still can't actually read the
key.
(2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
work as Other has been replaced with Everyone in the ACL.
Signed-off-by: David Howells <dhowells@redhat.com>
We can not hold the GlobalMid_Lock spinlock during the
dfs processing in cifs_reconnect since it invokes things that may sleep
and thus trigger :
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23
Thus we need to drop the spinlock during this code block.
RHBZ: 1716743
Cc: stable@vger.kernel.org
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The locking in force_sig_info is not prepared to deal with a task that
exits or execs (as sighand may change). The is not a locking problem
in force_sig as force_sig is only built to handle synchronous
exceptions.
Further the function force_sig_info changes the signal state if the
signal is ignored, or blocked or if SIGNAL_UNKILLABLE will prevent the
delivery of the signal. The signal SIGKILL can not be ignored and can
not be blocked and SIGNAL_UNKILLABLE won't prevent it from being
delivered.
So using force_sig rather than send_sig for SIGKILL is confusing
and pointless.
Because it won't impact the sending of the signal and and because
using force_sig is wrong, replace force_sig with send_sig.
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Jeff Layton <jlayton@primarydata.com>
Cc: Steve French <smfrench@gmail.com>
Fixes: a5c3e1c725 ("Revert "cifs: No need to send SIGKILL to demux_thread during umount"")
Fixes: e7ddee9037 ("cifs: disable sharing session and tcon and add new TCP sharing code")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
SMBDirect manages its own ports in the transport layer, there is no need to
check the port to find a connection.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie sahlberg <lsahlber@redhat.com>
commit 214bab4484 ("cifs: Call MID callback before destroying transport")
assumes that the MID callback should not take srv_mutex, this may not always
be true. SMB Direct requires the MID callback completed before calling
transport so all pending memory registration can be freed. So restore the
original calling sequence so TCP transport will use the same code, but moving
smbd_destroy() after all MID has been called.
fixes: 214bab4484 ("cifs: Call MID callback before destroying transport")
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
When transport is being destroyed, it's possible that some processes may
hold memory registrations that need to be deregistred.
Call them first so nobody is using transport resources, and it can be
destroyed.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
On transport recoonect, upper layer CIFS code destroys the current
transport and then recoonect. This code path is not used by SMBD, in that
SMBD destroys its transport on RDMA disconnect notification independent of
CIFS upper layer behavior.
This approach adds some costs to SMBD layer to handle transport shutdown
and restart, and to deal with several racing conditions on reconnecting
transport.
Re-work this code path by introducing a new smbd_destroy. This function is
called form upper layer to ask SMBD to destroy the transport. SMBD will no
longer need to destroy the transport by itself while worrying about data
transfer is in progress. The upper layer guarantees the transport is
locked.
change log:
v2: fix build errors when CONFIG_CIFS_SMB_DIRECT is not configured
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
As per MS-DFSC, when a DFS cache entry is expired and it is a DFS
link, then a new DFS referral must be sent to root server in order to
refresh the expired entry.
This patch ensures that all new DFS referrals for refreshing the cache
are sent to DFS root.
Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reconnecting after server or network failure can be improved
(to maintain availability and protect data integrity) by allowing
the client to choose the default persistent (or resilient)
handle timeout in some use cases. Today we default to 0 which lets
the server pick the default timeout (usually 120 seconds) but this
can be problematic for some workloads. Add the new mount parameter
to cifs.ko for SMB3 mounts "handletimeout" which enables the user
to override the default handle timeout for persistent (mount
option "persistenthandles") or resilient handles (mount option
"resilienthandles"). Maximum allowed is 16 minutes (960000 ms).
Units for the timeout are expressed in milliseconds. See
section 2.2.14.2.12 and 2.2.31.3 of the MS-SMB2 protocol
specification for more information.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Detected by CoverityScan CID#1438719 ("Unused Value")
buf is reset again before being used so these two lines of code
are useless.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Every time after a session reconnect we don't need to account for
credits obtained in previous sessions. Introduce new struct cifs_credits
which contains both credits value and reconnect instance of the
time those credits were taken. Modify a routine that add credits
back to handle the reconnect instance by assuming zero credits
if the reconnect happened after the credits were obtained and
before we decided to add them back due to some errors during sending.
This patch fixes the MTU credits cases. The subsequent patch
will handle non-MTU ones.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently we set reconnect instance to zero on the first
connection but this is not convenient because we need to
reserve some special value for credit handling on reconnects
which is coming in subsequent patches. Fix this by starting
with one when initiating a new TCP connection.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Even if a response is malformed, we should count credits
granted by the server to avoid miscalculations and unnecessary
reconnects due to client or server bugs. If the response has
been received partially, the session will be reconnected anyway
on the next iteration of the demultiplex thread, so counting
credits for such cases shouldn't break things.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We negotiate rsize mounts (and it can be overridden by user) to
typically 4MB, so using larger default I/O sizes from userspace
(changing to 1MB default i/o size returned by stat) the
performance is much better (and not just for long latency
network connections) in most use cases for SMB3 than the default I/O
size (which ends up being 128K for cp and can be even smaller for cp).
This can be 4x slower or worse depending on network latency.
By changing inode->blocksize from 32K (which was perhaps ok
for very old SMB1/CIFS) to a larger value, 1MB (but still less than
max size negotiated with the server which is 4MB, in order to minimize
risk) it significantly increases performance for the
noncached case, and slightly increases it for the cached case.
This can be changed by the user on mount (specifying bsize=
values from 16K to 16MB) to tune better for performance
for applications that depend on blocksize.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
We should add any credits granted to us from unmatched server responses.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
a trivial patch that replaces all use of snprintf with scnprintf.
scnprintf() is generally seen as a safer function to use than
snprintf for many use cases.
In our case, there is no actual difference between the two since we never
look at the return value. Thus we did not have any of the bugs that
scnprintf protects against and the patch does nothing.
However, for people reading our code it will be a receipt that we
have done our due dilligence and checked our code for this type of bugs.
See the presentation "Making C Less Dangerous In The Linux Kernel"
at this years LCA
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
There is a NULL pointer dereference of devname in strspn()
The oops looks something like:
CIFS: Attempting to mount (null)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
...
RIP: 0010:strspn+0x0/0x50
...
Call Trace:
? cifs_parse_mount_options+0x222/0x1710 [cifs]
? cifs_get_volume_info+0x2f/0x80 [cifs]
cifs_setup_volume_info+0x20/0x190 [cifs]
cifs_get_volume_info+0x50/0x80 [cifs]
cifs_smb3_do_mount+0x59/0x630 [cifs]
? ida_alloc_range+0x34b/0x3d0
cifs_do_mount+0x11/0x20 [cifs]
mount_fs+0x52/0x170
vfs_kern_mount+0x6b/0x170
do_mount+0x216/0xdc0
ksys_mount+0x83/0xd0
__x64_sys_mount+0x25/0x30
do_syscall_64+0x65/0x220
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fix this by adding a NULL check on devname in cifs_parse_devname()
Signed-off-by: Yao Liu <yotta.liu@ucloud.cn>
Signed-off-by: Steve French <stfrench@microsoft.com>
When executing add_credits() we currently call cifs_reconnect()
if the number of credits is zero and there are no requests in
flight. In this case we may call cifs_reconnect() recursively
twice and cause memory corruption given the following sequence
of functions:
mid1.callback() -> add_credits() -> cifs_reconnect() ->
-> mid2.callback() -> add_credits() -> cifs_reconnect().
Fix this by avoiding to call cifs_reconnect() in add_credits()
and checking for zero credits in the demultiplex thread.
Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This debug message was never shown because it was checking for NULL
returns but extract_hostname() returns error pointers.
Fixes: 93d5cb517d ("cifs: Add support for failover in cifs_reconnect()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
When DFS is not used on the mount we should not be mentioning
DFS in the warning message on reconnect (it could be confusing).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
In case a hostname resolves to a different IP address (e.g. long
running mounts), make sure to resolve it every time prior to calling
generic_ip_connect() in reconnect.
Suggested-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix potential NULL ptr deref when DFS target list is empty.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Start the DFS cache refresh worker per volume during cifs mount.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
A spin lock is held before kstrndup, it may sleep with holding
the spinlock, so we should use GFP_ATOMIC instead.
Fixes: e58c31d5e387 ("cifs: Add support for failover in cifs_reconnect()")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
After failing to reconnect to original target, it will retry any
target available from DFS cache.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch adds support for failover when failing to connect in
cifs_mount().
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This patch will make use of DFS cache routines where appropriate and
do not always request a new referral from server.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
* Add new dfs_cache.[ch] files
* Add new /proc/fs/cifs/dfscache file
- dump current cache when read
- clear current cache when writing "0" to it
* Add delayed_work to periodically refresh cache entries
The new interface will be used for caching DFS referrals, as well as
supporting client target failover.
The DFS cache is a hashtable that maps UNC paths to cache entries.
A cache entry contains:
- the UNC path it is mapped on
- how much the the UNC path the entry consumes
- flags
- a Time-To-Live after which the entry expires
- a list of possible targets (linked lists of UNC paths)
- a "hint target" pointing the last known working target or the first
target if none were tried. This hint lets cifs.ko remember and try
working targets first.
* Looking for an entry in the cache is done with dfs_cache_find()
- if no valid entries are found, a DFS query is made, stored in the
cache and returned
- the full target list can be copied and returned to avoid race
conditions and looped on with the help with the
dfs_cache_tgt_iterator
* Updating the target hint to the next target is done with
dfs_cache_update_tgthint()
These functions have a dfs_cache_noreq_XXX() version that doesn't
fetches referrals if no entries are found. These versions don't
require the tcp/ses/tcon/cifs_sb parameters as a result.
Expired entries cannot be used and since they have a pretty short TTL
[1] in order for them to be useful for failover the DFS cache adds a
delayed work called periodically to keep them fresh.
Since we might not have available connections to issue the referral
request when refreshing we need to store volume_info structs with
credentials and other needed info to be able to connect to the right
server.
1: Windows defaults: 5mn for domain-based referrals, 30mn for regular
links
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Different servers have different set of file ids.
After failover, unique IDs will be different so we can't validate
them.
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
When extracting hostname from UNC, check for leading backslashes
before trying to remove them.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
* Split and refactor the very large function cifs_mount() in multiple
functions:
- tcp, ses and tcon setup to mount_get_conns()
- tcp, ses and tcon cleanup in mount_put_conns()
- tcon tlink setup to mount_setup_tlink()
- remote path checking to is_path_remote()
* Implement 2 version of cifs_mount() for DFS-enabled builds and
non-DFS-enabled builds (CONFIG_CIFS_DFS_UPCALL).
In preparation for DFS failover support.
Signed-off-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
To avoid the warning:
warning: this statement may fall through [-Wimplicit-fallthrough=]
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steve French <stfrench@microsoft.com>
Technically 3.02 is not the dialect name although that is more familiar to
many, so we should also accept the official dialect name (3.0.2 vs. 3.02)
in vers=
Signed-off-by: Kenneth D'souza <kdsouza@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull AFS updates from Al Viro:
"AFS series, with some iov_iter bits included"
* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
missing bits of "iov_iter: Separate type from direction and use accessor functions"
afs: Probe multiple fileservers simultaneously
afs: Fix callback handling
afs: Eliminate the address pointer from the address list cursor
afs: Allow dumping of server cursor on operation failure
afs: Implement YFS support in the fs client
afs: Expand data structure fields to support YFS
afs: Get the target vnode in afs_rmdir() and get a callback on it
afs: Calc callback expiry in op reply delivery
afs: Fix FS.FetchStatus delivery from updating wrong vnode
afs: Implement the YFS cache manager service
afs: Remove callback details from afs_callback_break struct
afs: Commit the status on a new file/dir/symlink
afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
afs: Don't invoke the server to read data beyond EOF
afs: Add a couple of tracepoints to log I/O errors
afs: Handle EIO from delivery function
afs: Fix TTL on VL server and address lists
afs: Implement VL server rotation
afs: Improve FS server rotation error handling
...
In network file system it is fairly easy for server and client
atime vs. mtime to get confused (and atime updated less frequently)
which we noticed broke some apps which expect atime >= mtime
Also ignore relatime mount option (rather than error on it) since
relatime is basically what some network server fs are doing
(relatime).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
As we reset credits later in the reconnect path, useful
to have optional (cifsFYI) debug message.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
tcon->Flags is only used by SMB1 code and changing it is not permanent
(you lose the setting on tcon reconnect).
* Move the setting to superblock flags (per mount-points).
* Make automount callback exit early when flag present
* Make dfs resolving happening in mount syscall exit early if flag present
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Each time we reconnect to the same server, bump an instance
counter (and display in /proc/fs/cifs/DebugData) to make it
easier to debug.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.
Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.
Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.
Signed-off-by: David Howells <dhowells@redhat.com>
Fixes problem (discovered by Aurelien) introduced by recent commit:
commit b24df3e30c
("cifs: update receive_encrypted_standard to handle compounded responses")
which broke the ability to respond to some lease breaks
(lease breaks being ignored is a problem since can block
server response for duration of the lease break timeout).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
cifs_delete_mid() is called once we are finished handling a mid and we
expect no more work done on this mid.
Needed to fix recent commit:
commit 730928c8f4
("cifs: update smb2_queryfs() to use compounding")
Add a warning if someone tries to dequeue a mid that has already been
flagged to be deleted.
Also change list_del() to list_del_init() so that if we have similar bugs
resurface in the future we will not oops.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
This patch is required allows access to a Microsoft fileserver failover
cluster behind a 1:1 NAT firewall.
The change also provides stronger context for authentication and share
connection (see MS-SMB2 3.3.5.7 and MS-SRVS 3.1.6.8) as noted by
Tom Talpey, and addresses comments about the buffer size for the UNC
made by Aurélien Aptel.
Signed-off-by: Thomas Werschlein <thomas.werschlein@geo.uzh.ch>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Tom Talpey <ttalpey@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Add tracepoints for reconnecting an smb3 session
Example output (from trace-cmd) with the patch
(showing the session marked for reconnect, the stat failing, and then
the subsequent SMB3 commands after the server comes back up).
The "smb3_reconnect" event is the new one.
cifsd-25993 [000] .... 29635.368265: smb3_reconnect: server=localhost current_mid=0x1e
stat-26200 [001] .... 29638.516403: smb3_enter: cifs_revalidate_dentry_attr: xid=22
stat-26200 [001] .... 29648.723296: smb3_exit_err: cifs_revalidate_dentry_attr: xid=22 rc=-112
kworker/0:1-22830 [000] .... 29653.850947: smb3_cmd_done: sid=0x0 tid=0x0 cmd=0 mid=0
kworker/0:1-22830 [000] .... 29653.851191: smb3_cmd_err: sid=0x8ae4683c tid=0x0 cmd=1 mid=1 status=0xc0000016 rc=-5
kworker/0:1-22830 [000] .... 29653.855254: smb3_cmd_done: sid=0x8ae4683c tid=0x0 cmd=1 mid=2
kworker/0:1-22830 [000] .... 29653.855482: smb3_cmd_done: sid=0x8ae4683c tid=0x8084f30d cmd=3 mid=3
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
We really, really want to be encouraging use of secure dialects,
and SMB3.1.1 offers useful security features, and will soon
be the recommended dialect for many use cases. Simplify the code
by removing the CONFIG_CIFS_SMB311 ifdef so users don't disable
it in the build, and create compatibility and/or security issues
with modern servers - many of which have been supporting this
dialect for multiple years.
Also clarify some of the Kconfig text for cifs.ko about
SMB3.1.1 and current supported features in the module.
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
allow disabling cifs (SMB1 ie vers=1.0) and vers=2.0 in the
config for the build of cifs.ko if want to always prevent mounting
with these less secure dialects.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
If user specifies "posix" on an SMB3.11 mount, then fail the mount
if server does not return the POSIX negotiate context indicating
support for posix.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.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>
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>
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>
