The name_len variable in CIFSFindNext is a signed int that gets set to
the resume_name_len in the cifs_search_info. The resume_name_len however
is unsigned and for some infolevels is populated directly from a 32 bit
value sent by the server.
If the server sends a very large value for this, then that value could
look negative when converted to a signed int. That would make that
value pass the PATH_MAX check later in CIFSFindNext. The name_len would
then be used as a length value for a memcpy. It would then be treated
as unsigned again, and the memcpy scribbles over a ton of memory.
Fix this by making the name_len an unsigned value in CIFSFindNext.
Cc: <stable@kernel.org>
Reported-by: Darren Lavender <dcl@hppine99.gbr.hp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Reported-and-acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The recent fix to the above function causes this compiler warning to pop
on some gcc versions:
CC [M] fs/cifs/cifssmb.o
fs/cifs/cifssmb.c: In function ‘CIFSSMBQAllEAs’:
fs/cifs/cifssmb.c:5708: warning: ‘ea_name_len’ may be used uninitialized in
this function
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The code that matches EA names in CIFSSMBQAllEAs is incorrect. It
uses strncmp to do the comparison with the length limited to the
name_len sent in the response.
Problem: Suppose we're looking for an attribute named "foobar" and
have an attribute before it in the EA list named "foo". The
comparison will succeed since we're only looking at the first 3
characters. Fix this by also comparing the length of the provided
ea_name with the name_len in the response. If they're not equal then
it shouldn't match.
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Fix authentication failures using extended security mechanisms.
cifs client does not take into consideration extended security bit
in capabilities field in negotiate protocol response from the server.
Please refer to Samba bugzilla 8046.
Reported-and-tested by: Werner Maes <Werner.Maes@icts.kuleuven.be>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Add rwpidforward mount option that switches on a mode when we forward
pid of a process who opened a file to any read and write operation.
This can prevent applications like WINE from failing on read or write
operation on a previously locked file region from the same netfd from
another process if we use mandatory brlock style.
It is actual for WINE because during a run of WINE program two processes
work on the same netfd - share the same file struct between several VFS
fds:
1) WINE-server does open and lock;
2) WINE-application does read and write.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
We need it to make them work with mandatory locking style because
we can fail in a situation like when kernel need to flush dirty pages
and there is a lock held by a process who opened file.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Add the ability for CIFS to do an asynchronous write. The kernel will
set the frame up as it would for a "normal" SMBWrite2 request, and use
cifs_call_async to send it. The mid callback will then be configured to
handle the result.
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The current code always ignores the max_pending limit. Have it instead
only optionally ignore the pending limit. For CIFSSMBEcho, we need to
ignore it to make sure they always can go out. For async reads, writes
and potentially other calls, we need to respect it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
We'll need this for async writes, so convert the call to take a kvec
array. CIFSSMBEcho is changed to put a kvec on the stack and pass
in the SMB buffer using that.
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
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>
There is one big endian field in the cifs protocol, the RFC1001
length, which cifs code (unlike in the smb2 code) had been handling as
u32 until the last possible moment, when it was converted to be32 (its
native form) before sending on the wire. To remove the last sparse
endian warning, and to make this consistent with the smb2
implementation (which always treats the fields in their
native size and endianness), convert all uses of smb_buf_length to
be32.
This version incorporates Christoph's comment about
using be32_add_cpu, and fixes a typo in the second
version of the patch.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The comment about checking the bcc is in the wrong place. Also make it
match kernel coding style.
Reported-and-acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Remove config flag CIFS_EXPERIMENTAL.
Do export operations under new config flag CIFS_NFSD_EXPORT
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Recent Windows versions now create symlinks more frequently
and they do use this "reparse point" symlink mechanism. We can of course
do symlinks nicely to Samba and other servers which support the
CIFS Unix Extensions and we can also do SFU symlinks and "client only"
"MF" symlinks optionally, but for recent Windows we currently can not
handle the common "reparse point" symlinks fully, removing the caller
for this. We will need to extend and reenable this "reparse point" worker
code in cifs and fix cifs_symlink to call this. In the interim this code
has been moved to its own config option so it is not compiled in by default
until cifs_symlink fixed up (and tested) to use this.
CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
The CIFSSMBNotify worker is unused, pending changes to allow it to be called
via inotify, so move it into its own experimental config option so it does
not get built in, until the necessary VFS support is fixed. It used to
be used in dnotify, but according to Jeff, inotify needs minor changes
before we can reenable this.
CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When the TCP_Server_Info is first allocated and connected, tcpStatus ==
CifsGood means that the NEGOTIATE_PROTOCOL request has completed and the
socket is ready for other calls. cifs_reconnect however sets tcpStatus
to CifsGood as soon as the socket is reconnected and the optional
RFC1001 session setup is done. We have no clear way to tell the
difference between these two states, and we need to know this in order
to know whether we can send an echo or not.
Resolve this by adding a new statusEnum value -- CifsNeedNegotiate. When
the socket has been connected but has not yet had a NEGOTIATE_PROTOCOL
request done, set it to this value. Once the NEGOTIATE is done,
cifs_negotiate_protocol will set tcpStatus to CifsGood.
This also fixes and cleans the logic in cifs_reconnect and
cifs_reconnect_tcon. The old code checked for specific states when what
it really wants to know is whether the state has actually changed from
CifsNeedReconnect.
Reported-and-Tested-by: JG <jg@cms.ac>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
make modules C=2 M=fs/cifs CF=-D__CHECK_ENDIAN__
Found for example:
CHECK fs/cifs/cifssmb.c
fs/cifs/cifssmb.c:728:22: warning: incorrect type in assignment (different base types)
fs/cifs/cifssmb.c:728:22: expected unsigned short [unsigned] [usertype] Tid
fs/cifs/cifssmb.c:728:22: got restricted __le16 [usertype] <noident>
fs/cifs/cifssmb.c:1883:45: warning: incorrect type in assignment (different base types)
fs/cifs/cifssmb.c:1883:45: expected long long [signed] [usertype] fl_start
fs/cifs/cifssmb.c:1883:45: got restricted __le64 [usertype] start
fs/cifs/cifssmb.c:1884:54: warning: restricted __le64 degrades to integer
fs/cifs/cifssmb.c:1885:58: warning: restricted __le64 degrades to integer
fs/cifs/cifssmb.c:1886:43: warning: incorrect type in assignment (different base types)
fs/cifs/cifssmb.c:1886:43: expected unsigned int [unsigned] fl_pid
fs/cifs/cifssmb.c:1886:43: got restricted __le32 [usertype] pid
In checking new smb2 code for missing endian conversions, I noticed
some endian errors had crept in over the last few releases into the
cifs code (symlink, ntlmssp, posix lock, and also a less problematic warning
in fscache). A followon patch will address a few smb2 endian
problems.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
ses->status is never set to CifsExiting, so these checks are
always false.
Tested-by: JG <jg@cms.ac>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
New compiler warnings that I noticed when building a patchset based
on recent Fedora kernel:
fs/cifs/cifssmb.c: In function 'CIFSSMBSetFileSize':
fs/cifs/cifssmb.c:4813:8: warning: variable 'data_offset' set but not used
[-Wunused-but-set-variable]
fs/cifs/file.c: In function 'cifs_open':
fs/cifs/file.c:349:24: warning: variable 'pCifsInode' set but not used
[-Wunused-but-set-variable]
fs/cifs/file.c: In function 'cifs_partialpagewrite':
fs/cifs/file.c:1149:23: warning: variable 'cifs_sb' set but not used
[-Wunused-but-set-variable]
fs/cifs/file.c: In function 'cifs_iovec_write':
fs/cifs/file.c:1740:9: warning: passing argument 6 of 'CIFSSMBWrite2' from
incompatible pointer type [enabled by default]
fs/cifs/cifsproto.h:337:12: note: expected 'unsigned int *' but argument is
of type 'size_t *'
fs/cifs/readdir.c: In function 'cifs_readdir':
fs/cifs/readdir.c:767:23: warning: variable 'cifs_sb' set but not used
[-Wunused-but-set-variable]
fs/cifs/cifs_dfs_ref.c: In function 'cifs_dfs_d_automount':
fs/cifs/cifs_dfs_ref.c:342:2: warning: 'rc' may be used uninitialized in
this function [-Wuninitialized]
fs/cifs/cifs_dfs_ref.c:278:6: note: 'rc' was declared here
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Make sure that CIFSSMBEcho can handle unaligned fields. Also fix a minor
bug that causes this warning:
fs/cifs/cifssmb.c: In function 'CIFSSMBEcho':
fs/cifs/cifssmb.c:740: warning: large integer implicitly truncated to unsigned type
...WordCount is u8, not __le16, so no need to convert it.
This patch should apply cleanly on top of the rest of the patchset to
clean up unaligned access.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...and clean up function to reduce indentation.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
It's possible that when we access the ByteCount that the alignment
will be off. Most CPUs deal with that transparently, but there's
usually some performance impact. Some CPUs raise an exception on
unaligned accesses.
Fix this by accessing the byte count using the get_unaligned and
put_unaligned inlined functions. While we're at it, fix the types
of some of the variables that end up getting returns from these
functions.
Acked-by: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Remove fields that are completely unused, and rearrange struct
according to recommendations by "pahole".
Before:
/* size: 1112, cachelines: 18, members: 49 */
/* sum members: 1086, holes: 8, sum holes: 26 */
/* bit holes: 1, sum bit holes: 7 bits */
/* last cacheline: 24 bytes */
After:
/* size: 1072, cachelines: 17, members: 42 */
/* sum members: 1065, holes: 3, sum holes: 7 */
/* last cacheline: 48 bytes */
...savings of 40 bytes per struct on x86_64. 21 bytes by field removal,
and 19 by reorganizing to eliminate holes.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Since we don't time out individual requests anymore, remove the code
that we used to use for setting timeouts on different requests.
Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When we get oplock break notification we should set the appropriate
value of OplockLevel field in oplock break acknowledge according to
the oplock level held by the client in this time. As we only can have
level II oplock or no oplock in the case of oplock break, we should be
aware only about clientCanCacheRead field in cifsInodeInfo structure.
Also fix bug connected with wrong interpretation of OplockLevel field
during oplock break notification processing.
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
I see no real need to leave these sorts of options under an
EXPERIMENTAL ifdef. Since you need a mount option to turn this code
on, that only blows out the testing matrix.
local_leases has been under the EXPERIMENTAL tag for some time, but
it's only the mount option that's under this label. Move it out
from under this tag.
The NTLMSSP code is also under EXPERIMENTAL, but it needs a mount
option to turn it on, and in the future any distro will reasonably
want this enabled. Go ahead and move it out from under the
EXPERIMENTAL tag.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Some of the code under CONFIG_CIFS_ACL is dependent upon code under
CONFIG_CIFS_EXPERIMENTAL, but the Kconfig options don't reflect that
dependency. Move more of the ACL code out from under
CONFIG_CIFS_EXPERIMENTAL and under CONFIG_CIFS_ACL.
Also move find_readable_file out from other any sort of Kconfig
option and make it a function normally compiled in.
Reported-and-Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Need to have cryptkey or server challenge in smb connection
(struct TCP_Server_Info) for ntlm and ntlmv2 auth types for which
cryptkey (Encryption Key) is supplied just once in Negotiate Protocol
response during an smb connection setup for all the smb sessions over
that smb connection.
For ntlmssp, cryptkey or server challenge is provided for every
smb session in type 2 packet of ntlmssp negotiation, the cryptkey
provided during Negotiation Protocol response before smb connection
does not count.
Rename cryptKey to cryptkey and related changes.
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.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>
Convert this lock to a regular spinlock
A rwlock_t offers little value here. It's more expensive than a regular
spinlock unless you have a fairly large section of code that runs under
the read lock and can benefit from the concurrency.
Additionally, we need to ensure that the refcounting for files isn't
racy and to do that we need to lock areas that can increment it for
write. That means that the areas that can actually use a read_lock are
very few and relatively infrequently used.
While we're at it, change the name to something easier to type, and fix
a bug in find_writable_file. cifsFileInfo_put can sleep and shouldn't be
called while holding the lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Start calculation auth response within a session. Move/Add pertinet
data structures like session key, server challenge and ntlmv2_hash in
a session structure. We should do the calculations within a session
before copying session key and response over to server data
structures because a session setup can fail.
Only after a very first smb session succeeds, it copies/makes its
session key, session key of smb connection. This key stays with
the smb connection throughout its life.
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
cifs_reconnect_tcon is called from smb_init. After a successful
reconnect, cifs_reconnect_tcon will call reset_cifs_unix_caps. That
function will, in turn call CIFSSMBQFSUnixInfo and CIFSSMBSetFSUnixInfo.
Those functions also call smb_init.
It's possible for the session and tcon reconnect to succeed, and then
for another cifs_reconnect to occur before CIFSSMBQFSUnixInfo or
CIFSSMBSetFSUnixInfo to be called. That'll cause those functions to call
smb_init and cifs_reconnect_tcon again, ad infinitum...
Break the infinite recursion by having those functions use a new
smb_init variant that doesn't attempt to perform a reconnect.
Reported-and-Tested-by: Michal Suchanek <hramrach@centrum.cz>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Attribue Value (AV) pairs or Target Info (TI) pairs are part of
ntlmv2 authentication.
Structure ntlmv2_resp had only definition for two av pairs.
So removed it, and now allocation of av pairs is dynamic.
For servers like Windows 7/2008, av pairs sent by server in
challege packet (type 2 in the ntlmssp exchange/negotiation) can
vary.
Server sends them during ntlmssp negotiation. So when ntlmssp is used
as an authentication mechanism, type 2 challenge packet from server
has this information. Pluck it and use the entire blob for
authenticaiton purpose. If user has not specified, extract
(netbios) domain name from the av pairs which is used to calculate
ntlmv2 hash. Servers like Windows 7 are particular about the AV pair
blob.
Servers like Windows 2003, are not very strict about the contents
of av pair blob used during ntlmv2 authentication.
So when security mechanism such as ntlmv2 is used (not ntlmv2 in ntlmssp),
there is no negotiation and so genereate a minimal blob that gets
used in ntlmv2 authentication as well as gets sent.
Fields tilen and tilbob are session specific. AV pair values are defined.
To calculate ntlmv2 response we need ti/av pair blob.
For sec mech like ntlmssp, the blob is plucked from type 2 response from
the server. From this blob, netbios name of the domain is retrieved,
if user has not already provided, to be included in the Target String
as part of ntlmv2 hash calculations.
For sec mech like ntlmv2, create a minimal, two av pair blob.
The allocated blob is freed in case of error. In case there is no error,
this blob is used in calculating ntlmv2 response (in CalcNTLMv2_response)
and is also copied on the response to the server, and then freed.
The type 3 ntlmssp response is prepared on a buffer,
5 * sizeof of struct _AUTHENTICATE_MESSAGE, an empirical value large
enough to hold _AUTHENTICATE_MESSAGE plus a blob with max possible
10 values as part of ntlmv2 response and lmv2 keys and domain, user,
workstation names etc.
Also, kerberos gets selected as a default mechanism if server supports it,
over the other security mechanisms.
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This reverts commit 9fbc590860.
The change to kernel crypto and fixes to ntlvm2 and ntlmssp
series, introduced a regression. Deferring this patch series
to 2.6.37 after Shirish fixes it.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
CC: Shirish Pargaonkar <shirishp@us.ibm.com>
Make ntlmv2 as an authentication mechanism within ntlmssp
instead of ntlmv1.
Parse type 2 response in ntlmssp negotiation to pluck
AV pairs and use them to calculate ntlmv2 response token.
Also, assign domain name from the sever response in type 2
packet of ntlmssp and use that (netbios) domain name in
calculation of response.
Enable cifs/smb signing using rc4 and md5.
Changed name of the structure mac_key to session_key to reflect
the type of key it holds.
Use kernel crypto_shash_* APIs instead of the equivalent cifs functions.
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...rather than the secType. This allows us to get rid of the MSKerberos
securityEnum. The client just makes a decision at upcall time.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
So that we can reasonably set up the secType based on both the
NegotiateProtocol response and the parsed mount options.
Signed-off-by: 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>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
not overwriting file_lock structure after GET_LK
cifs: Fix a kernel BUG with remote OS/2 server (try #3)
[CIFS] initialize nbytes at the beginning of CIFSSMBWrite()
[CIFS] Add mmap for direct, nobrl cifs mount types
If we have preventing lock, cifs should overwrite file_lock structure
with info about preventing lock. If we haven't preventing lock, cifs
should leave it unchanged except for the lock type (change it to F_UNLCK).
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
While chasing a bug report involving a OS/2 server, I noticed the server sets
pSMBr->CountHigh to a incorrect value even in case of normal writes. This
results in 'nbytes' being computed wrongly and triggers a kernel BUG at
mm/filemap.c.
void iov_iter_advance(struct iov_iter *i, size_t bytes)
{
BUG_ON(i->count < bytes); <--- BUG here
Why the server is setting 'CountHigh' is not clear but only does so after
writing 64k bytes. Though this looks like the server bug, the client side
crash may not be acceptable.
The workaround is to mask off high 16 bits if the number of bytes written as
returned by the server is greater than the bytes requested by the client as
suggested by Jeff Layton.
CC: Stable <stable@kernel.org>
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
By doing this we always overwrite nbytes value that is being passed on to
CIFSSMBWrite() and need not rely on the callers to initialize. CIFSSMBWrite2 is
doing this already.
CC: Stable <stable@kernel.org>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@samba.org>
Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
