Under some conditions, CIFS can repeatedly call the cifs_dbg() logging
wrapper. If done rapidly enough, the console framebuffer can softlockup
or "rcu_sched self-detected stall". Apply the built-in log ratelimiters
to prevent such hangs.
Signed-off-by: Jamie Bainbridge <jamie.bainbridge@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
If CONFIG_CIFS_WEAK_PW_HASH is not set, CIFSSEC_MUST_LANMAN
and CIFSSEC_MUST_PLNTXT is defined as 0.
When setting new SecurityFlags without any MUST flags,
your flags would be overwritten with CIFSSEC_MUST_LANMAN (0).
Signed-off-by: Niklas Cassel <niklass@axis.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
The useful macros embed message level in the name. Thus, it cleans up the code
a bit. In cases when it was plain printk() the conversion was done to info
level.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
This patch converts custom dumper to use native print_hex_dump() instead. The
cifs_dump_mem() will have an offsets per each line which differs it from the
original code.
In the dump_smb() we may use native print_hex_dump() as well. It will show
slightly different output in ASCII part when character is unprintable,
otherwise it keeps same structure.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Steve French <steve.french@primarydata.com>
Meanwhile it cleans up the code, the behaviour is slightly changed. In case of
providing non-boolean value it will fails with corresponding error. In the
original code the attempt of an update was just ignored in such case.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Reviewed-by: Alexander Bokovoy <ab@samba.org>
Signed-off-by: Steve French <steve.french@primarydata.com>
Joe Perches and Hans Wennborg noticed that various places in the
kernel were printing decimal numbers with 0x prefix.
printk("0x%d") or equivalent
This fixes the instances of this in the cifs driver.
CC: Hans Wennborg <hans@hanshq.net>
CC: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <smfrench@gmail.com>
The cifs.ko SecurityFlags interface wins my award for worst-designed
interface ever, but we're sort of stuck with it since it's documented
and people do use it (even if it doesn't work correctly).
Case in point -- you can specify multiple sets of "MUST" flags. It makes
absolutely no sense, but you can do it.
What should the effect be in such a case? No one knows or seems to have
considered this so far, so let's define it now. If you try to specify
multiple MUST flags, clear any other MAY or MUST bits except for the
ones that involve signing.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
SMB3 protocol adds various optional per-share capabilities (and
SMB3.02 adds one more beyond that). Add ability to dump
(/proc/fs/cifs/DebugData) the share capabilities and share flags to
improve debugging.
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
The SecurityFlags handler uses an obsolete simple_strtoul() call, and
doesn't really handle the bounds checking well. Fix it to use
kstrtouint() instead. Clean up the error messages as well and fix a
bogus check for an unsigned int to be less than 0.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
It's not obvious from reading the macro names that these macros
are for debugging. Convert the names to a single more typical
kernel style cifs_dbg macro.
cERROR(1, ...) -> cifs_dbg(VFS, ...)
cFYI(1, ...) -> cifs_dbg(FYI, ...)
cFYI(DBG2, ...) -> cifs_dbg(NOISY, ...)
Move the terminating format newline from the macro to the call site.
Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the
"CIFS VFS: " prefix for VFS messages.
Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y)
$ size fs/cifs/cifs.ko*
text data bss dec hex filename
265245 2525 132 267902 4167e fs/cifs/cifs.ko.new
268359 2525 132 271016 422a8 fs/cifs/cifs.ko.old
Other miscellaneous changes around these conversions:
o Miscellaneous typo fixes
o Add terminating \n's to almost all formats and remove them
from the macros to be more kernel style like. A few formats
previously had defective \n's
o Remove unnecessary OOM messages as kmalloc() calls dump_stack
o Coalesce formats to make grep easier,
added missing spaces when coalescing formats
o Use %s, __func__ instead of embedded function name
o Removed unnecessary "cifs: " prefixes
o Convert kzalloc with multiply to kcalloc
o Remove unused cifswarn macro
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Now we can process SMB2 messages: check message, get message id
and wakeup awaiting routines.
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
by making it as unsigned integer and surround access with req_lock
from server structure.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
We'll allow a grace period of 2 releases (3.3 and 3.4) and then remove
the legacy code in 3.5.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
The plan is to deprecate this interface by kernel version 3.4.
Changes since v1
- add a '\n' to the printk.
Reported-by: Alexander Swen <alex@swen.nu>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
Thus spake Jeff Layton:
"Making that a module parm would allow you to set that parameter at boot
time without needing to add special startup scripts. IMO, all of the
procfile "switches" under /proc/fs/cifs should be module parms
instead."
This patch doesn't alter the default behavior (Oplocks are enabled by
default).
To disable oplocks when loading the module, use
modprobe cifs enable_oplocks=0
(any of '0' or 'n' or 'N' conventions can be used).
To disable oplocks at runtime using the new interface, use
echo 0 > /sys/module/cifs/parameters/enable_oplocks
The older /proc/fs/cifs/OplockEnabled interface will be deprecated
after two releases. A subsequent patch will add an warning message
about this deprecation.
Changes since v2:
- make enable_oplocks a 'bool'
Changes since v1:
- eliminate the use of extra variable by renaming the old one to
enable_oplocks and make it an 'int' type.
Reported-by: Alexander Swen <alex@swen.nu>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
Christoph had requested that the stats related code (in
CONFIG_CIFS_STATS2) be moved into helpers to make code flow more
readable. This patch should help. For example the following
section from transport.c
spin_unlock(&GlobalMid_Lock);
atomic_inc(&ses->server->num_waiters);
wait_event(ses->server->request_q,
atomic_read(&ses->server->inFlight)
< cifs_max_pending);
atomic_dec(&ses->server->num_waiters);
spin_lock(&GlobalMid_Lock);
becomes simpler (with the patch below):
spin_unlock(&GlobalMid_Lock);
cifs_num_waiters_inc(server);
wait_event(server->request_q,
atomic_read(&server->inFlight)
< cifs_max_pending);
cifs_num_waiters_dec(server);
spin_lock(&GlobalMid_Lock);
Reviewed-by: Jeff Layton <jlayton@redhat.com>
CC: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
This is the same patch as originally posted, just with some merge
conflicts fixed up...
Currently, the ByteCount is usually converted to host-endian on receive.
This is confusing however, as we need to keep two sets of routines for
accessing it, and keep track of when to use each routine. Munging
received packets like this also limits when the signature can be
calulated.
Simplify the code by keeping the received ByteCount in little-endian
format. This allows us to eliminate a set of routines for accessing it
and we can now drop the *_le suffixes from the accessor functions since
that's now implied.
While we're at it, switch all of the places that read the ByteCount
directly to use the get_bcc inline which should also clean up some
unaligned accesses.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This flag currently only affects whether we allow "zero-copy" writes
with signing enabled. Typically we map pages in the pagecache directly
into the write request. If signing is enabled however and the contents
of the page change after the signature is calculated but before the
write is sent then the signature will be wrong. Servers typically
respond to this by closing down the socket.
Still, this can provide a performance benefit so the "Experimental" flag
was overloaded to allow this. That's really not a good place for this
option however since it's not clear what that flag does.
Move that flag instead to a new module parameter that better describes
its purpose. That's also better since it can be set at module insertion
time by configuring modprobe.d.
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
In order to incorporate async requests, we need to allow for a more
general way to do things on receive, rather than just waking up a
process.
Turn the task pointer in the mid_q_entry into a callback function and a
generic data pointer. When a response comes in, or the socket is
reconnected, cifsd can call the callback function in order to wake up
the process.
The default is to just wake up the current process which should mean no
change in behavior for existing code.
Also, clean up the locking in cifs_reconnect. There doesn't seem to be
any need to hold both the srv_mutex and GlobalMid_Lock when walking the
list of mids.
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
It's an atomic_t and the code accesses the "counter" field in it directly
instead of using atomic_read(). It also is sometimes accessed under a
spinlock and sometimes not. Move it out of the spinlock since we don't need
belt-and-suspenders for something that's just informational.
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...and while we're at it, reduce the number of calls into the seq_*
functions by prepending spaces to strings.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
cifs_tcp_ses_lock is a rwlock with protects the cifs_tcp_ses_list,
server->smb_ses_list and the ses->tcon_list. It also protects a few
ref counters in server, ses and tcon. In most cases the critical section
doesn't seem to be large, in a few cases where it is slightly large, there
seem to be really no benefit from concurrent access. I briefly considered RCU
mechanism but it appears to me that there is no real need.
Replace it with a spinlock and get rid of the last rwlock in the cifs code.
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Fixed the nit pointed out by Jeff.
From: Suresh Jayaraman <sjayaraman@suse.de>
Subject: [PATCH 1/2] cifs: show features compiled in as part of DebugData
This patch adds the features that are compiled in to the CIFS debugging data
as shown below:
$cat /proc/fs/cifs/DebugData
Display Internal CIFS Data Structures for Debugging
---------------------------------------------------
CIFS Version 1.64
Features: dfs fscache posix spnego xattr
Active VFS Requests: 0
...
This patch provides a definitive way to tell what features are currently
enabled in the running kernel. This could also help debugging.
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Cc: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...since that more accurately describes what that variable holds.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Neaten cERROR and cFYI macros, reduce text space
~2.5K
Convert '__FILE__ ": " fmt' to '"%s: " fmt', __FILE__' to save text space
Surround macros with do {} while
Add parentheses to macros
Make statement expression macro from macro with assign
Remove now unnecessary parentheses from cFYI and cERROR uses
defconfig with CIFS support old
$ size fs/cifs/built-in.o
text data bss dec hex filename
156012 1760 148 157920 268e0 fs/cifs/built-in.o
defconfig with CIFS support old
$ size fs/cifs/built-in.o
text data bss dec hex filename
153508 1760 148 155416 25f18 fs/cifs/built-in.o
allyesconfig old:
$ size fs/cifs/built-in.o
text data bss dec hex filename
309138 3864 74824 387826 5eaf2 fs/cifs/built-in.o
allyesconfig new
$ size fs/cifs/built-in.o
text data bss dec hex filename
305655 3864 74824 384343 5dd57 fs/cifs/built-in.o
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
In contrast to the now-obsolete smbfs, cifs does not send SMB_COM_FLUSH
in response to an explicit fsync(2) to guarantee that all volatile data
is written to stable storage on the server side, provided the server
honors the request (which, to my knowledge, is true for Windows and
Samba with 'strict sync' enabled).
This patch modifies the cifs_fsync implementation to restore the
fsync-behavior of smbfs by triggering SMB_COM_FLUSH after sending
outstanding data on the client side to the server.
Signed-off-by: Horst Reiterer <horst.reiterer@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Use a similar approach to the SMB session sharing. Add a list of tcons
attached to each SMB session. Move the refcount to non-atomic. Protect
all of the above with the cifs_tcp_ses_lock. Add functions to
properly find and put references to the tcons.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
We do this by abandoning the global list of SMB sessions and instead
moving to a per-server list. This entails adding a new list head to the
TCP_Server_Info struct. The refcounting for the cifsSesInfo is moved to
a non-atomic variable. We have to protect it by a lock anyway, so there's
no benefit to making it an atomic. The list and refcount are protected
by the global cifs_tcp_ses_lock.
The patch also adds a new routines to find and put SMB sessions and
that properly take and put references under the lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The code that allows these structs to be shared is extremely racy.
Disable the sharing of SMB and tcon structs for now until we can
come up with a way to do this that's race free.
We want to continue to share TCP sessions, however since they are
required for multiuser mounts. For that, implement a new (hopefully
race-free) scheme. Add a new global list of TCP sessions, and take
care to get a reference to it whenever we're dealing with one.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Also adds two lines missing from the previous patch (for the need reconnect flag in the
/proc/fs/cifs/DebugData handling)
The new global_cifs_sock_list is added, and initialized in init_cifs but not used yet.
Jeff Layton will be adding code in to use that and to remove the GlobalTcon and GlobalSMBSession
lists.
CC: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Use creation by full path instead: "fs/foo".
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christoph had noticed too many ifdefs in the CIFS code making it
hard to read. This patch removes about a quarter of them from
the C files in cifs by improving a few key ifdefs in the .h files.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Fixes two problems:
1) we dropped down to negotiating lanman if we did not recognize the
mechanism (krb5 e.g.)
2) we did not stop cifsd (thus will fail when doing rmod cifs with
slab free errors) when we fail tcon but have a bad session (which is
the case in which signing is required but we don't allow signing on
the client)
It also turns on extended security flag in the header when passing
"sec=krb5" on mount command (although kerberos support is not done of
course)
Acked-by: Jeff Layton <jlayton@redhat.com>
CC: Shaggy <shaggy@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
