Fix RedHat bug 329431
The idea here is separate "conscious" from "unconscious" flushes.
Conscious flushes are those due to a fsync() or close(). Unconscious
ones are flushes that occur as a side effect of some other operation or
due to memory pressure.
Currently, when an error occurs during an unconscious flush (ENOSPC or
EIO), we toss out the page and don't preserve that error to report to
the user when a conscious flush occurs. If after the unconscious flush,
there are no more dirty pages for the inode, the conscious flush will
simply return success even though there were previous errors when writing
out pages. This can lead to data corruption.
The easiest way to reproduce this is to mount up a CIFS share that's
very close to being full or where the user is very close to quota. mv
a file to the share that's slightly larger than the quota allows. The
writes will all succeed (since they go to pagecache). The mv will do a
setattr to set the new file's attributes. This calls
filemap_write_and_wait,
which will return an error since all of the pages can't be written out.
Then later, when the flush and release ops occur, there are no more
dirty pages in pagecache for the file and those operations return 0. mv
then assumes that the file was written out correctly and deletes the
original.
CIFS already has a write_behind_rc variable where it stores the results
from earlier flushes, but that value is only reported in cifs_close.
Since the VFS ignores the return value from the release operation, this
isn't helpful. We should be reporting this error during the flush
operation.
This patch does the following:
1) changes cifs_fsync to use filemap_write_and_wait and cifs_flush and also
sync to check its return code. If it returns successful, they then check
the value of write_behind_rc to see if an earlier flush had reported any
errors. If so, they return that error and clear write_behind_rc.
2) sets write_behind_rc in a few other places where pages are written
out as a side effect of other operations and the code waits on them.
3) changes cifs_setattr to only call filemap_write_and_wait for
ATTR_SIZE changes.
4) makes cifs_writepages accurately distinguish between EIO and ENOSPC
errors when writing out pages.
Some simple testing indicates that the patch works as expected and that
it fixes the reproduceable known problem.
Acked-by: Dave Kleikamp <shaggy@austin.rr.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When retrying kernel_recvmsg() because of a short read, check returned
length against the remaining length, not against total length. This
avoids unneeded session reconnects which would otherwise occur when
kernel_recvmsg() finally returns zero when asked to read zero bytes.
Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Have CIFS_SessSetup call cifs_get_spnego_key when Kerberos is
negotiated. Use the info in the key payload to build a session
setup request packet. Also clean up how the request buffer in
the function is freed on error.
With appropriate user space helper (in samba/source/client). Kerberos
support (secure session establishment can be done now via Kerberos,
previously users would have to use NTLMv2 instead for more secure
session setup).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...and populate it with the hostname portion of the UNC string.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Move all of the kfree's sprinkled in the middle of the function to the
end, and have the code set rc and just goto there on error. Also zero
out the password string before freeing it. Looks like this should also
fix a potential memory leak of the prepath string if an error occurs
near the end of the function.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
request
In SendReceive() function in transport.c - it memcpy's
message payload into a buffer passed via out_buf param. The function
assumes that all buffers are of size (CIFSMaxBufSize +
MAX_CIFS_HDR_SIZE) , unfortunately it is also called with smaller
(MAX_CIFS_SMALL_BUFFER_SIZE) buffers. There are eight callers
(SMB worker functions) which are primarily affected by this change:
TreeDisconnect, uLogoff, Close, findClose, SetFileSize, SetFileTimes,
Lock and PosixLock
CC: Dave Kleikamp <shaggy@austin.ibm.com>
CC: Przemyslaw Wegrzyn <czajnik@czajsoft.pl>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
...and fix a couple of bugs in the NBD, CIFS and OCFS2 socket handlers.
Looking at the sock->op->shutdown() handlers, it looks as if all of them
take a SHUT_RD/SHUT_WR/SHUT_RDWR argument instead of the
RCV_SHUTDOWN/SEND_SHUTDOWN arguments.
Add a helper, and then define the SHUT_* enum to ensure that kernel users
of shutdown() don't get confused.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (21 commits)
[CIFS] fix oops on second mount to same server when null auth is used
[CIFS] Fix stale mode after readdir when cifsacl specified
[CIFS] add mode to acl conversion helper function
[CIFS] Fix incorrect mode when ACL had deny access control entries
[CIFS] Add uid to key description so krb can handle user mounts
[CIFS] Fix walking out end of cifs dacl
[CIFS] Add upcall files for cifs to use spnego/kerberos
[CIFS] add OIDs for KRB5 and MSKRB5 to ASN1 parsing routines
[CIFS] Register and unregister cifs_spnego_key_type on module init/exit
[CIFS] implement upcalls for SPNEGO blob via keyctl API
[CIFS] allow cifs_calc_signature2 to deal with a zero length iovec
[CIFS] If no Access Control Entries, set mode perm bits to zero
[CIFS] when mount helper missing fix slash wrong direction in share
[CIFS] Don't request too much permission when reading an ACL
[CIFS] enable get mode from ACL when cifsacl mount option specified
[CIFS] ACL support part 8
[CIFS] acl support part 7
[CIFS] acl support part 6
[CIFS] acl support part 6
[CIFS] remove unused funtion compile warning when experimental off
...
When a share is mounted using no username, cifs_mount sets
volume_info.username as a NULL pointer, and the sesInfo userName as an
empty string. The volume_info.username is passed to a couple of other
functions to see if there is an existing unc or tcp connection that can
be used. These functions assume that the username will be a valid
string that can be passed to strncmp. If the pointer is NULL, then the
kernel will oops if there's an existing session to which the string
can be compared.
This patch changes cifs_mount to set volume_info.username to an empty
string in this situation, which prevents the oops and should make it
so that the comparison to other null auth sessions match.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When mounted with cifsacl mount option, readdir can not
instantiate the inode with the estimated mode based on the ACL
for each file since we have not queried for the ACL for
each of these files yet. So set the refresh time to zero
for these inodes so that the next stat will cause the client
to go to the server for the ACL info so we can build the estimated
mode (this means we also will issue an extra QueryPathInfo if
the stat happens within 1 second, but this is trivial compared to
the time required to open/getacl/close for each).
ls -l is slower when cifsacl mount option is specified, but
displays correct mode information.
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When mounted with the cifsacl mount option, we were
treating any deny ACEs found like allow ACEs and it turns out for
SFU and SUA Windows set these type of access control entries often.
The order of ACEs is important too. The canonical order that most
ACL tools and Windows explorer consruct ACLs with is to begin with
DENY entries then follow with ALLOW, otherwise an allow entry
could be encountered first, making the subsequent deny entry like "dead
code which would be superflous since Windows stops when a match is
made for the operation you are trying to perform for your user
We start with no permissions in the mode and build up as we find
permissions (ie allow ACEs). This fixes deny ACEs so they affect
the mask used to set the subsequent allow ACEs.
Acked-by: Shirish Pargaonkar <shirishp@us.ibm.com>
CC: Alexander Bokovoy <ab@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Adds uid to key description fro supporting user mounts
and minor formating changes
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Igor Mammedov <niallain@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Also, fix the parser to recognize them and set the secType
accordingly. Make CIFSSMBNegotiate not error out automatically
after parsing the securityBlob.
Also thanks to Q (Igor) and Simo for their help on this
set of kerberos patches (and Dave Howells for help on the
upcall).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Add routines to handle upcalls to userspace via keyctl for the purpose
of getting a SPNEGO blob for a particular uid and server combination.
Clean up the Makefile a bit and set it up to only compile cifs_spnego
if CONFIG_CIFS_UPCALL is set. Also change CONFIG_CIFS_UPCALL to depend
on CONFIG_KEYS rather than CONFIG_CONNECTOR.
cifs_spnego.h defines the communications between kernel and userspace
and is intended to be shared with userspace programs.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Currently, cifs_calc_signature2 errors out if it gets a zero-length
iovec. Fix it to silently continue in that case.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Kernel bugzilla bug #9228
If mount helper (mount.cifs) missing, mounts with form like
//10.11.12.13/c$ would not work (only mounts with slash e.g.
//10.11.12.13\\c$ would work) due to problem with slash supposed
to be converted to backslash by the mount helper (which is not
there).
If we fail on converting an IPv4 address in in4_pton then
try to canonicalize the first slash (ie between sharename
and host ip address) if necessary. If we have to retry
to check for IPv6 address the slash is already converted
if necessary.
Signed-off-by: Steve French <sfrench@us.ibm.com>
We were requesting GENERIC_READ but that fails when we do not have
read permission on the file (even if we could read the ACL).
Also move the dump access control entry code into debug ifdef.
Signed-off-by: Steve French <sfrench@us.ibm.com>
Part 9 of ACL patch series. getting mode from ACL now works in
some cases (and requires CIFS_EXPERIMENTAL config option).
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Now GetACL in getinodeinfo path when cifsacl mount option used, and
ACL is parsed for SIDs. Missing only one piece now to be able
to retrieve the mode
Signed-off-by: Steve French <sfrench@us.ibm.com>
get rid of couple of unused function warnings which
show up when CONFIG_CIFS_EXPERIMENTAL is not defined - wrap them in
#ifdef CONFIG_CIFS_EXPERIMENTAL. Patch against current git.
Signed-off-by: Parag Warudkar <kernel-stuff@comcast.net>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Now that nfsd has stopped writing to the find_exported_dentry member we an
mark the export_operations const
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (51 commits)
[CIFS] log better errors on failed mounts
[CIFS] Return better error when server requires signing but client forbids
[CIFS] fix typo
[CIFS] acl support part 4
[CIFS] Fix minor problems noticed by scan
[CIFS] fix bad handling of EAGAIN error on kernel_recvmsg in cifs_demultiplex_thread
[CIFS] build break
[CIFS] endian fixes
[CIFS] endian fixes in new acl code
[CIFS] Fix some endianness problems in new acl code
[CIFS] missing #endif from a previous patch
[CIFS] formatting fixes
[CIFS] Break up unicode_sessetup string functions
[CIFS] parse server_GUID in SPNEGO negProt response
[CIFS]
[CIFS] Fix endian conversion problem in posix mkdir
[CIFS] fix build break when lanman not enabled
[CIFS] remove two sparse warnings
[CIFS] remove compile warnings when debug disabled
[CIFS] CIFS ACL support part 3
...
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.
The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.
[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Also returns more accurate errors to mount for the cases of
account expired and password expired
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
If the ATTR_KILL_S*ID bits are set then any mode change is only for clearing
the setuid/setgid bits. For CIFS, skip the mode change and let the server
handle it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When kernel_recvmsg returns -EAGAIN or -ERESTARTSYS, then
cifs_demultiplex_thread sleeps for a bit and then tries the read again.
When it does this, it's not zeroing out the length and that throws off
the value of total_read. Fix it to zero out the length.
Can cause memory corruption:
If kernel_recvmsg returns an error and total_read is a large enough
value, then we'll end up going through the loop again. total_read will
be a bogus value, as will (pdu_length-total_read). When this happens we
end up calling kernel_recvmsg with a bogus value (possibly larger than
the current iov_len).
At that point, memcpy_toiovec can overrun iov. It will start walking
up the stack, casting other things that are there to struct iovecs
(since it assumes that it's been passed an array of them). Any pointer
on the stack at an address above the kvec is a candidate for corruption
here.
Many thanks to Ulrich Obergfell for pointing this out.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Slab constructors currently have a flags parameter that is never used. And
the order of the arguments is opposite to other slab functions. The object
pointer is placed before the kmem_cache pointer.
Convert
ctor(void *object, struct kmem_cache *s, unsigned long flags)
to
ctor(struct kmem_cache *s, void *object)
throughout the kernel
[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
