Commit Graph

48485 Commits

Author SHA1 Message Date
Jeff Layton
a1f4020aab libceph: allow requests to return immediately on full conditions if caller wishes
Usually, when the osd map is flagged as full or the pool is at quota,
write requests just hang. This is not what we want for cephfs, where
it would be better to simply report -ENOSPC back to userland instead
of stalling.

If the caller knows that it will want an immediate error return instead
of blocking on a full or at-quota error condition then allow it to set a
flag to request that behavior.

Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller),
and on any other write request from ceph.ko.

A later patch will deal with requests that were submitted before the new
map showing the full condition came in.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:21 +02:00
Yan, Zheng
79162547b7 ceph: make seeky readdir more efficient
Current cephfs client uses string to indicate start position of
readdir. The string is last entry of previous readdir reply.
This approach does not work for seeky readdir because we can
not easily convert the new postion to a string. For seeky readdir,
mds needs to return dentries from the beginning. Client keeps
retrying if the reply does not contain the dentry it wants.

In current version of ceph, mds sorts CDentry in its cache in
hash order. Client also uses dentry hash to compose dir postion.
For seeky readdir, if client passes the hash part of dir postion
to mds. mds can avoid replying useless dentries.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:20 +02:00
Yan, Zheng
2827528da0 ceph: close stopped mds' session
If a mds has stopped, close its session and clean up its session
requests/caps. The process is similar to handling SESSION_CLOSE
initiated by mds.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:20 +02:00
Yan, Zheng
0a07fc8cd0 ceph: fix potential use-after-free
__unregister_session() free the session if it drops the last
reference. We should grab an extra reference if we want to use
session after __unregister_session().

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:20 +02:00
Yan, Zheng
76201b6354 ceph: allow connecting to mds whose rank >= mdsmap::m_max_mds
mdsmap::m_max_mds is the expected count of active mds. It's not the
max rank of active mds. User can decrease mdsmap::m_max_mds, but does
not stop mds whose rank >= mdsmap::m_max_mds.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:20 +02:00
Yan, Zheng
8242c9f35a ceph: fix wrong check in ceph_renew_caps()
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:19 +02:00
Elena Reshetova
0e1a5ee657 libceph: convert ceph_pagelist.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:19 +02:00
Elena Reshetova
805692d0e0 ceph: convert ceph_cap_snap.nref from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:18 +02:00
Elena Reshetova
3997c01d26 ceph: convert ceph_mds_session.s_ref from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:18 +02:00
Ilya Dryomov
74da4a0f57 libceph, ceph: always advertise all supported features
No reason to hide CephFS-specific features in the rbd case.  Recent
feature bits mix RADOS and CephFS-specific stuff together anyway.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04 09:19:18 +02:00
Linus Torvalds
28b2013587 Merge branch 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fix from Chris Mason:
 "We have one more fix for btrfs.

  This gets rid of a new WARN_ON from rc1 that ended up making more
  noise than we really want. The larger fix for the underflow got
  delayed a bit and it's better for now to put it under
  CONFIG_BTRFS_DEBUG"

* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: qgroup: move noisy underflow warning to debugging build
2017-04-28 10:13:17 -07:00
Linus Torvalds
8b5d11e4b0 Thanks to Ari Kauppi and Tuomas Haanpää at Synopsis for spotting bugs in
our NFSv2/v3 xdr code that could crash the server or leak memory.
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Merge tag 'nfsd-4.11-3' of git://linux-nfs.org/~bfields/linux

Pull nfsd fixes from Bruce Fields:
 "Thanks to Ari Kauppi and Tuomas Haanpää at Synopsis for spotting bugs
  in our NFSv2/v3 xdr code that could crash the server or leak memory"

* tag 'nfsd-4.11-3' of git://linux-nfs.org/~bfields/linux:
  nfsd: stricter decoding of write-like NFSv2/v3 ops
  nfsd4: minor NFSv2/v3 write decoding cleanup
  nfsd: check for oversized NFSv2/v3 arguments
2017-04-27 13:39:19 -07:00
Linus Torvalds
19ac447420 A fix for a kernel stack overflow bug in ceph setattr code, marked for
stable.
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Merge tag 'ceph-for-4.11-rc9' of git://github.com/ceph/ceph-client

Pull ceph fix from Ilya Dryomov:
 "A fix for a kernel stack overflow bug in ceph setattr code, marked for
  stable"

* tag 'ceph-for-4.11-rc9' of git://github.com/ceph/ceph-client:
  ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
2017-04-27 11:38:05 -07:00
Linus Torvalds
f56fc7bdaa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:

 - fix orangefs handling of faults on write() - I'd missed that one back
   when orangefs was going through review.

 - readdir counterpart of "9p: cope with bogus responses from server in
   p9_client_{read,write}" - server might be lying or broken, and we'd
   better not overrun the kmalloc'ed buffer we are copying the results
   into.

 - NFS O_DIRECT read/write can leave iov_iter advanced by too much;
   that's what had been causing iov_iter_pipe() warnings davej had been
   seeing.

 - statx_timestamp.tv_nsec type fix (s32 -> u32). That one really should
   go in before 4.11.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  uapi: change the type of struct statx_timestamp.tv_nsec to unsigned
  fix nfs O_DIRECT advancing iov_iter too much
  p9_client_readdir() fix
  orangefs_bufmap_copy_from_iovec(): fix EFAULT handling
2017-04-27 11:09:37 -07:00
Michael Kerrisk (man-pages)
59372bbf3a statx: correct error handling of NULL pathname
The change in commit 1e2f82d1e9 ("statx: Kill fd-with-NULL-path
support in favour of AT_EMPTY_PATH") to error on a NULL pathname to
statx() is inconsistent.

It results in the error EINVAL for a NULL pathname.  Other system calls
with similar APIs (fchownat(), fstatat(), linkat()), return EFAULT.

The solution is simply to remove the EINVAL check.  As I already pointed
out in [1], user_path_at*() and filename_lookup() will handle the NULL
pathname as per the other APIs, to correctly produce the error EFAULT.

[1] https://lkml.org/lkml/2017/4/26/561

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-27 10:45:09 -07:00
David Howells
1e2f82d1e9 statx: Kill fd-with-NULL-path support in favour of AT_EMPTY_PATH
With the new statx() syscall, the following both allow the attributes of
the file attached to a file descriptor to be retrieved:

	statx(dfd, NULL, 0, ...);

and:

	statx(dfd, "", AT_EMPTY_PATH, ...);

Change the code to reject the first option, though this means copying
the path and engaging pathwalk for the fstat() equivalent.  dfd can be a
non-directory provided path is "".

[ The timing of this isn't wonderful, but applying this now before we
  have statx() in any released kernel, before anybody starts using the
  NULL special case.    - Linus ]

Fixes: a528d35e8b ("statx: Add a system call to make enhanced file info available")
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric Sandeen <sandeen@sandeen.net>
cc: fstests@vger.kernel.org
cc: linux-api@vger.kernel.org
cc: linux-man@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-26 15:05:47 -07:00
J. Bruce Fields
13bf9fbff0 nfsd: stricter decoding of write-like NFSv2/v3 ops
The NFSv2/v3 code does not systematically check whether we decode past
the end of the buffer.  This generally appears to be harmless, but there
are a few places where we do arithmetic on the pointers involved and
don't account for the possibility that a length could be negative.  Add
checks to catch these.

Reported-by: Tuomas Haanpää <thaan@synopsys.com>
Reported-by: Ari Kauppi <ari@synopsys.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 16:36:23 -04:00
J. Bruce Fields
db44bac41b nfsd4: minor NFSv2/v3 write decoding cleanup
Use a couple shortcuts that will simplify a following bugfix.

Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 16:36:16 -04:00
J. Bruce Fields
e6838a29ec nfsd: check for oversized NFSv2/v3 arguments
A client can append random data to the end of an NFSv2 or NFSv3 RPC call
without our complaining; we'll just stop parsing at the end of the
expected data and ignore the rest.

Encoded arguments and replies are stored together in an array of pages,
and if a call is too large it could leave inadequate space for the
reply.  This is normally OK because NFS RPC's typically have either
short arguments and long replies (like READ) or long arguments and short
replies (like WRITE).  But a client that sends an incorrectly long reply
can violate those assumptions.  This was observed to cause crashes.

Also, several operations increment rq_next_page in the decode routine
before checking the argument size, which can leave rq_next_page pointing
well past the end of the page array, causing trouble later in
svc_free_pages.

So, following a suggestion from Neil Brown, add a central check to
enforce our expectation that no NFSv2/v3 call has both a large call and
a large reply.

As followup we may also want to rewrite the encoding routines to check
more carefully that they aren't running off the end of the page array.

We may also consider rejecting calls that have any extra garbage
appended.  That would be safer, and within our rights by spec, but given
the age of our server and the NFS protocol, and the fact that we've
never enforced this before, we may need to balance that against the
possibility of breaking some oddball client.

Reported-by: Tuomas Haanpää <thaan@synopsys.com>
Reported-by: Ari Kauppi <ari@synopsys.com>
Cc: stable@vger.kernel.org
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-25 16:34:37 -04:00
Yan, Zheng
8179a101eb ceph: fix recursion between ceph_set_acl() and __ceph_setattr()
ceph_set_acl() calls __ceph_setattr() if the setacl operation needs
to modify inode's i_mode. __ceph_setattr() updates inode's i_mode,
then calls posix_acl_chmod().

The problem is that __ceph_setattr() calls posix_acl_chmod() before
sending the setattr request. The get_acl() call in posix_acl_chmod()
can trigger a getxattr request. The reply of the getxattr request
can restore inode's i_mode to its old value. The set_acl() call in
posix_acl_chmod() sees old value of inode's i_mode, so it calls
__ceph_setattr() again.

Cc: stable@vger.kernel.org # needs backporting for < 4.9
Link: http://tracker.ceph.com/issues/19688
Reported-by: Jerry Lee <leisurelysw24@gmail.com>
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-04-25 21:08:26 +02:00
Linus Torvalds
9ea33c44fb This pull request contains fixes for issues in both UBI and UBIFS:
- More O_TMPFILE fallout
 - RENAME_WHITEOUT regression due to a mis-merge
 - Memory leak in ubifs_mknod()
 - Power-cut problem in UBI's update volume feature
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Merge tag 'upstream-4.11-rc7' of git://git.infradead.org/linux-ubifs

Pull UBI/UBIFS fixes from Richard Weinberger:
 "This contains fixes for issues in both UBI and UBIFS:

   - more O_TMPFILE fallout

   - RENAME_WHITEOUT regression due to a mis-merge

   - memory leak in ubifs_mknod()

   - power-cut problem in UBI's update volume feature"

* tag 'upstream-4.11-rc7' of git://git.infradead.org/linux-ubifs:
  ubifs: Fix O_TMPFILE corner case in ubifs_link()
  ubifs: Fix RENAME_WHITEOUT support
  ubifs: Fix debug messages for an invalid filename in ubifs_dump_inode
  ubifs: Fix debug messages for an invalid filename in ubifs_dump_node
  ubifs: Remove filename from debug messages in ubifs_readdir
  ubifs: Fix memory leak in error path in ubifs_mknod
  ubi/upd: Always flush after prepared for an update
2017-04-23 16:49:16 -07:00
Linus Torvalds
94836ecf1e Fix a 4.11 regression that triggers a BUG() on an attempt to use an
unsupported NFSv4 compound op.
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Merge tag 'nfsd-4.11-2' of git://linux-nfs.org/~bfields/linux

Pull nfsd bugfix from Bruce Fields:
 "Fix a 4.11 regression that triggers a BUG() on an attempt to use an
  unsupported NFSv4 compound op"

* tag 'nfsd-4.11-2' of git://linux-nfs.org/~bfields/linux:
  nfsd: fix oops on unsupported operation
2017-04-21 16:37:48 -07:00
Linus Torvalds
4988f7a40f Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fix from Steve French:
 "One more cifs fix for stable"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: Do not send echoes before Negotiate is complete
2017-04-19 17:12:46 -07:00
Cong Wang
073c516ff7 nsfs: mark dentry with DCACHE_RCUACCESS
Andrey reported a use-after-free in __ns_get_path():

  spin_lock include/linux/spinlock.h:299 [inline]
  lockref_get_not_dead+0x19/0x80 lib/lockref.c:179
  __ns_get_path+0x197/0x860 fs/nsfs.c:66
  open_related_ns+0xda/0x200 fs/nsfs.c:143
  sock_ioctl+0x39d/0x440 net/socket.c:1001
  vfs_ioctl fs/ioctl.c:45 [inline]
  do_vfs_ioctl+0x1bf/0x1780 fs/ioctl.c:685
  SYSC_ioctl fs/ioctl.c:700 [inline]
  SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691

We are under rcu read lock protection at that point:

        rcu_read_lock();
        d = atomic_long_read(&ns->stashed);
        if (!d)
                goto slow;
        dentry = (struct dentry *)d;
        if (!lockref_get_not_dead(&dentry->d_lockref))
                goto slow;
        rcu_read_unlock();

but don't use a proper RCU API on the free path, therefore a parallel
__d_free() could free it at the same time.  We need to mark the stashed
dentry with DCACHE_RCUACCESS so that __d_free() will be called after all
readers leave RCU.

Fixes: e149ed2b80 ("take the targets of /proc/*/ns/* symlinks to separate fs")
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-19 15:56:24 -07:00
David Sterba
338bd52f3c btrfs: qgroup: move noisy underflow warning to debugging build
The WARN_ON and warning from report_reserved_underflow can become very
noisy and is visible unconditionally although this is namely for
debugging. The patch "btrfs: Add WARN_ON for qgroup reserved underflow"
(18dc22c19b) went to 4.11-rc1 and the plan
was to get the fix as well, but this hasn't happened.

CC: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-19 12:40:49 +02:00
Richard Weinberger
32fe905c17 ubifs: Fix O_TMPFILE corner case in ubifs_link()
It is perfectly fine to link a tmpfile back using linkat().
Since tmpfiles are created with a link count of 0 they appear
on the orphan list, upon re-linking the inode has to be removed
from the orphan list again.

Ralph faced a filesystem corruption in combination with overlayfs
due to this bug.

Cc: <stable@vger.kernel.org>
Cc: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Reported-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Tested-by: Ralph Sennhauser <ralph.sennhauser@gmail.com>
Reported-by: Amir Goldstein <amir73il@gmail.com>
Fixes: 474b93704f ("ubifs: Implement O_TMPFILE")
Signed-off-by: Richard Weinberger <richard@nod.at>
2017-04-18 23:18:02 +02:00
Sachin Prabhu
62a6cfddcc cifs: Do not send echoes before Negotiate is complete
commit 4fcd1813e6 ("Fix reconnect to not defer smb3 session reconnect
long after socket reconnect") added support for Negotiate requests to
be initiated by echo calls.

To avoid delays in calling echo after a reconnect, I added the patch
introduced by the commit b8c600120f ("Call echo service immediately
after socket reconnect").

This has however caused a regression with cifs shares which do not have
support for echo calls to trigger Negotiate requests. On connections
which need to call Negotiation, the echo calls trigger an error which
triggers a reconnect which in turn triggers another echo call. This
results in a loop which is only broken when an operation is performed on
the cifs share. For an idle share, it can DOS a server.

The patch uses the smb_operation can_echo() for cifs so that it is
called only if connection has been already been setup.

kernel bz: 194531

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Tested-by: Jonathan Liu <net147@gmail.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-17 15:44:23 -05:00
Al Viro
85128b2be6 fix nfs O_DIRECT advancing iov_iter too much
It leaves the iterator advanced by the amount of IO it has requested
instead of the amount actually transferred.  Among other things,
that confuses the hell out of generic_file_splice_read().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-17 14:23:20 -04:00
Al Viro
890559e34e orangefs_bufmap_copy_from_iovec(): fix EFAULT handling
short copy here should mean instant EFAULT, not "move to the
next page and hope it fails there, this time with nothing
copied"

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-17 14:23:20 -04:00
Martin Brandenburg
1ec1688c53 orangefs: free superblock when mount fails
Otherwise lockdep says:

[ 1337.483798] ================================================
[ 1337.483999] [ BUG: lock held when returning to user space! ]
[ 1337.484252] 4.11.0-rc6 #19 Not tainted
[ 1337.484423] ------------------------------------------------
[ 1337.484626] mount/14766 is leaving the kernel with locks still held!
[ 1337.484841] 1 lock held by mount/14766:
[ 1337.485017]  #0:  (&type->s_umount_key#33/1){+.+.+.}, at: [<ffffffff8124171f>] sget_userns+0x2af/0x520

Caught by xfstests generic/413 which tried to mount with the unsupported
mount option dax.  Then xfstests generic/422 ran sync which deadlocks.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Acked-by: Mike Marshall <hubcap@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-15 09:39:31 -07:00
Linus Torvalds
c0eb027e5a vfs: don't do RCU lookup of empty pathnames
Normal pathname lookup doesn't allow empty pathnames, but using
AT_EMPTY_PATH (with name_to_handle_at() or fstatat(), for example) you
can trigger an empty pathname lookup.

And not only is the RCU lookup in that case entirely unnecessary
(because we'll obviously immediately finalize the end result), it is
actively wrong.

Why? An empth path is a special case that will return the original
'dirfd' dentry - and that dentry may not actually be RCU-free'd,
resulting in a potential use-after-free if we were to initialize the
path lazily under the RCU read lock and depend on complete_walk()
finalizing the dentry.

Found by syzkaller and KASAN.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-15 09:34:52 -07:00
Linus Torvalds
4b31ac485d Merge branch 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Dave Sterba collected a few more fixes for the last rc.

  These aren't marked for stable, but I'm putting them in with a batch
  were testing/sending by hand for this release"

* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix potential use-after-free for cloned bio
  Btrfs: fix segmentation fault when doing dio read
  Btrfs: fix invalid dereference in btrfs_retry_endio
  btrfs: drop the nossd flag when remounting with -o ssd
2017-04-14 16:53:45 -07:00
Linus Torvalds
5466f4dfce Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull more CIFS fixes from Steve French:
 "As promised, here is the remaining set of cifs/smb3 fixes for stable
  (and a fix for one regression) now that they have had additional
  review and testing"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix SMB3 mount without specifying a security mechanism
  CIFS: store results of cifs_reopen_file to avoid infinite wait
  CIFS: remove bad_network_name flag
  CIFS: reconnect thread reschedule itself
  CIFS: handle guest access errors to Windows shares
  CIFS: Fix null pointer deref during read resp processing
2017-04-14 16:51:29 -07:00
Mike Kravetz
045c7a3f53 hugetlbfs: fix offset overflow in hugetlbfs mmap
If mmap() maps a file, it can be passed an offset into the file at which
the mapping is to start.  Offset could be a negative value when
represented as a loff_t.  The offset plus length will be used to update
the file size (i_size) which is also a loff_t.

Validate the value of offset and offset + length to make sure they do
not overflow and appear as negative.

Found by syzcaller with commit ff8c0c53c4 ("mm/hugetlb.c: don't call
region_abort if region_chg fails") applied.  Prior to this commit, the
overflow would still occur but we would luckily return ENOMEM.

To reproduce:

   mmap(0, 0x2000, 0, 0x40021, 0xffffffffffffffffULL, 0x8000000000000000ULL);

Resulted in,

  kernel BUG at mm/hugetlb.c:742!
  Call Trace:
   hugetlbfs_evict_inode+0x80/0xa0
   evict+0x24a/0x620
   iput+0x48f/0x8c0
   dentry_unlink_inode+0x31f/0x4d0
   __dentry_kill+0x292/0x5e0
   dput+0x730/0x830
   __fput+0x438/0x720
   ____fput+0x1a/0x20
   task_work_run+0xfe/0x180
   exit_to_usermode_loop+0x133/0x150
   syscall_return_slowpath+0x184/0x1c0
   entry_SYSCALL_64_fastpath+0xab/0xad

Fixes: ff8c0c53c4 ("mm/hugetlb.c: don't call region_abort if region_chg fails")
Link: http://lkml.kernel.org/r/1491951118-30678-1-git-send-email-mike.kravetz@oracle.com
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-13 18:24:21 -07:00
Kirill A. Shutemov
5b7abeae3a thp: fix MADV_DONTNEED vs clear soft dirty race
Yet another instance of the same race.

Fix is identical to change_huge_pmd().

See "thp: fix MADV_DONTNEED vs.  numa balancing race" for more details.

Link: http://lkml.kernel.org/r/20170302151034.27829-5-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-13 18:24:21 -07:00
Olga Kornievskaia
05b7278d51 nfsd: fix oops on unsupported operation
I'm hitting the BUG in nfsd4_max_reply() at fs/nfsd/nfs4proc.c:2495 when
client sends an operation the server doesn't support.

in nfsd4_max_reply() it checks for NULL rsize_bop but a non-supported
operation wouldn't have that set.

Cc: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 2282cd2c05 "NFSD: Get response size before operation..."
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-04-13 11:18:56 -04:00
Pavel Shilovsky
67dbea2ce6 CIFS: Fix SMB3 mount without specifying a security mechanism
Commit ef65aaede2 ("smb2: Enforce sec= mount option") changed the
behavior of a mount command to enforce a specified security mechanism
during mounting. On another hand according to the spec if SMB3 server
doesn't respond with a security context it implies that it supports
NTLMSSP. The current code doesn't keep it in mind and fails a mount
for such servers if no security mechanism is specified. Fix this by
indicating that a server supports NTLMSSP if a security context isn't
returned during negotiate phase. This allows the code to use NTLMSSP
by default for SMB3 mounts.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-13 10:03:26 -05:00
Liu Bo
a967efb30b Btrfs: fix potential use-after-free for cloned bio
KASAN reports that there is a use-after-free case of bio in btrfs_map_bio.

If we need to submit IOs to several disks at a time, the original bio
would get cloned and mapped to the destination disk, but we really should
use the original bio instead of a cloned bio to do the sanity check
because cloned bios are likely to be freed by its endio.

Reported-by: Diego <diegocg@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-11 18:49:56 +02:00
Liu Bo
97bf5a5589 Btrfs: fix segmentation fault when doing dio read
Commit 2dabb32484 ("Btrfs: Direct I/O read: Work on sectorsized blocks")
introduced this bug during iterating bio pages in dio read's endio hook,
and it could end up with segment fault of the dio reading task.

So the reason is 'if (nr_sectors--)', and it makes the code assume that
there is one more block in the same page, so page offset is increased and
the bio which is created to repair the bad block then has an incorrect
bvec.bv_offset, and a later access of the page content would throw a
segmentation fault.

This also adds ASSERT to check page offset against page size.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-11 18:49:29 +02:00
Liu Bo
2e949b0a55 Btrfs: fix invalid dereference in btrfs_retry_endio
When doing directIO repair, we have this oops:

[ 1458.532816] general protection fault: 0000 [#1] SMP
...
[ 1458.536291] Workqueue: btrfs-endio-repair btrfs_endio_repair_helper [btrfs]
[ 1458.536893] task: ffff88082a42d100 task.stack: ffffc90002b3c000
[ 1458.537499] RIP: 0010:btrfs_retry_endio+0x7e/0x1a0 [btrfs]
...
[ 1458.543261] Call Trace:
[ 1458.543958]  ? rcu_read_lock_sched_held+0xc4/0xd0
[ 1458.544374]  bio_endio+0xed/0x100
[ 1458.544750]  end_workqueue_fn+0x3c/0x40 [btrfs]
[ 1458.545257]  normal_work_helper+0x9f/0x900 [btrfs]
[ 1458.545762]  btrfs_endio_repair_helper+0x12/0x20 [btrfs]
[ 1458.546224]  process_one_work+0x34d/0xb70
[ 1458.546570]  ? process_one_work+0x29e/0xb70
[ 1458.546938]  worker_thread+0x1cf/0x960
[ 1458.547263]  ? process_one_work+0xb70/0xb70
[ 1458.547624]  kthread+0x17d/0x180
[ 1458.547909]  ? kthread_create_on_node+0x70/0x70
[ 1458.548300]  ret_from_fork+0x31/0x40

It turns out that btrfs_retry_endio is trying to get inode from a directIO
page.

This fixes the problem by using the saved inode pointer, done->inode.
btrfs_retry_endio_nocsum has the same problem, and it's fixed as well.

Also cleanup unused @start (which is too trivial for a separate patch).

Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-11 18:49:08 +02:00
Adam Borowski
951e796639 btrfs: drop the nossd flag when remounting with -o ssd
The opposite case was already handled right in the very next switch entry.
And also when turning on nossd, drop ssd_spread.

Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-11 18:48:59 +02:00
Germano Percossi
1fa839b498 CIFS: store results of cifs_reopen_file to avoid infinite wait
This fixes Continuous Availability when errors during
file reopen are encountered.

cifs_user_readv and cifs_user_writev would wait for ever if
results of cifs_reopen_file are not stored and for later inspection.

In fact, results are checked and, in case of errors, a chain
of function calls leading to reads and writes to be scheduled in
a separate thread is skipped.
These threads will wake up the corresponding waiters once reads
and writes are done.

However, given the return value is not stored, when rc is checked
for errors a previous one (always zero) is inspected instead.
This leads to pending reads/writes added to the list, making
cifs_user_readv and cifs_user_writev wait for ever.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-10 23:36:39 -05:00
Germano Percossi
a0918f1ce6 CIFS: remove bad_network_name flag
STATUS_BAD_NETWORK_NAME can be received during node failover,
causing the flag to be set and making the reconnect thread
always unsuccessful, thereafter.

Once the only place where it is set is removed, the remaining
bits are rendered moot.

Removing it does not prevent "mount" from failing when a non
existent share is passed.

What happens when the share really ceases to exist while the
share is mounted is undefined now as much as it was before.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-10 23:36:39 -05:00
Germano Percossi
18ea43113f CIFS: reconnect thread reschedule itself
In case of error, smb2_reconnect_server reschedule itself
with a delay, to avoid being too aggressive.

Signed-off-by: Germano Percossi <germano.percossi@citrix.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-10 23:36:39 -05:00
Mark Syms
40920c2bb1 CIFS: handle guest access errors to Windows shares
Commit 1a967d6c9b ("correctly to
anonymous authentication for the NTLM(v2) authentication") introduces
a regression in handling errors related to attempting a guest
connection to a Windows share which requires authentication. This
should result in a permission denied error but actually causes the
kernel module to enter a never-ending loop trying to follow a DFS
referal which doesn't exist.

The base cause of this is the failure now occurs later in the process
during tree connect and not at the session setup setup and all errors
in tree connect are interpreted as needing to follow the DFS paths
which isn't in this case correct. So, check the returned error against
EACCES and fail if this is returned error.

Feedback from Aurelien:

  PS> net user guest /activate:no
    PS> mkdir C:\guestshare
      PS> icacls C:\guestshare /grant 'Everyone:(OI)(CI)F'
        PS> new-smbshare -name guestshare -path C:\guestshare -fullaccess Everyone

        I've tested v3.10, v4.4, master, master+your patch using default options
        (empty or no user "NU") and user=abc (U).

        NT_LOGON_FAILURE in session setup: LF
        This is what you seem to have in 3.10.

        NT_ACCESS_DENIED in tree connect to the share: AD
        This is what you get before your infinite loop.

                     |   NU       U
                     --------------------------------
                     3.10         |   LF       LF
                     4.4          |   LF       LF
                     master       |   AD       LF
                     master+patch |   AD       LF

                     No infinite DFS loop :(
                     All these issues result in mount failing very fast with permission denied.

                     I guess it could be from either the Windows version or the share/folder
                     ACL. A deeper analysis of the packets might reveal more.

                     In any case I did not notice any issues for on a basic DFS setup with
                     the patch so I don't think it introduced any regressions, which is
                     probably all that matters. It still bothers me a little I couldn't hit
                     the bug.

                     I've included kernel output w/ debugging output and network capture of
                     my tests if anyone want to have a look at it. (master+patch = ml-guestfix).

Signed-off-by: Mark Syms <mark.syms@citrix.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Tested-by: Aurelien Aptel <aaptel@suse.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-10 23:36:38 -05:00
Pavel Shilovsky
350be257ea CIFS: Fix null pointer deref during read resp processing
Currently during receiving a read response mid->resp_buf can be
NULL when it is being passed to cifs_discard_remaining_data() from
cifs_readv_discard(). Fix it by always passing server->smallbuf
instead and initializing mid->resp_buf at the end of read response
processing.

Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Acked-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
2017-04-10 23:36:38 -05:00
Linus Torvalds
84ced7fd06 Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6
Pull CIFS fixes from Steve French:
 "This is a set of CIFS/SMB3 fixes for stable.

  There is another set of four SMB3 reconnect fixes for stable in
  progress but they are still being reviewed/tested, so didn't want to
  wait any longer to send these five below"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  Reset TreeId to zero on SMB2 TREE_CONNECT
  CIFS: Fix build failure with smb2
  Introduce cifs_copy_file_range()
  SMB3: Rename clone_range to copychunk_range
  Handle mismatched open calls
2017-04-09 09:10:02 -07:00
Linus Torvalds
5b50be743f Driver core fixes for 4.11-rc6
Here are 3 small fixes for 4.11-rc6.  One resolves a reported issue with
 sysfs files that NeilBrown found, one is a documenatation fix for the
 stable kernel rules, and the last is a small MAINTAINERS file update for
 kernfs.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are 3 small fixes for 4.11-rc6.

  One resolves a reported issue with sysfs files that NeilBrown found,
  one is a documenatation fix for the stable kernel rules, and the last
  is a small MAINTAINERS file update for kernfs"

* tag 'driver-core-4.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  MAINTAINERS: separate out kernfs maintainership
  sysfs: be careful of error returns from ops->show()
  Documentation: stable-kernel-rules: fix stable-tag format
2017-04-09 09:03:51 -07:00
Linus Torvalds
2a610b8aa8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS fixes from Al Viro:
 "statx followup fixes and a fix for stack-smashing on alpha"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  alpha: fix stack smashing in old_adjtimex(2)
  statx: Include a mask for stx_attributes in struct statx
  statx: Reserve the top bit of the mask for future struct expansion
  xfs: report crtime and attribute flags to statx
  ext4: Add statx support
  statx: optimize copy of struct statx to userspace
  statx: remove incorrect part of vfs_statx() comment
  statx: reject unknown flags when using NULL path
  Documentation/filesystems: fix documentation for ->getattr()
2017-04-09 08:26:21 -07:00
NeilBrown
c8a139d001 sysfs: be careful of error returns from ops->show()
ops->show() can return a negative error code.
Commit 65da3484d9 ("sysfs: correctly handle short reads on PREALLOC attrs.")
(in v4.4) caused this to be stored in an unsigned 'size_t' variable, so errors
would look like large numbers.
As a result, if an error is returned, sysfs_kf_read() will return the
value of 'count', typically 4096.

Commit 17d0774f80 ("sysfs: correctly handle read offset on PREALLOC attrs")
(in v4.8) extended this error to use the unsigned large 'len' as a size for
memmove().
Consequently, if ->show returns an error, then the first read() on the
sysfs file will return 4096 and could return uninitialized memory to
user-space.
If the application performs a subsequent read, this will trigger a memmove()
with extremely large count, and is likely to crash the machine is bizarre ways.

This bug can currently only be triggered by reading from an md
sysfs attribute declared with __ATTR_PREALLOC() during the
brief period between when mddev_put() deletes an mddev from
the ->all_mddevs list, and when mddev_delayed_delete() - which is
scheduled on a workqueue - completes.
Before this, an error won't be returned by the ->show()
After this, the ->show() won't be called.

I can reproduce it reliably only by putting delay like
	usleep_range(500000,700000);
early in mddev_delayed_delete(). Then after creating an
md device md0 run
  echo clear > /sys/block/md0/md/array_state; cat /sys/block/md0/md/array_state

The bug can be triggered without the usleep.

Fixes: 65da3484d9 ("sysfs: correctly handle short reads on PREALLOC attrs.")
Fixes: 17d0774f80 ("sysfs: correctly handle read offset on PREALLOC attrs")
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 17:33:32 +02:00