linux.git/fs, branch v3.9.8

libceph: wrap auth ops in wrapper functions

2013-06-20T19:01:32+00:00

commit 27859f9773e4a0b2042435b13400ee2c891a61f4 upstream.

Use wrapper functions that check whether the auth op exists so that callers
do not need a bunch of conditional checks.  Simplifies the external
interface.

Signed-off-by: Sage Weil 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

libceph: add update_authorizer auth method

2013-06-20T19:01:32+00:00

commit 0bed9b5c523d577378b6f83eab5835fe30c27208 upstream.

Currently the messenger calls out to a get_authorizer con op, which will
create a new authorizer if it doesn't yet have one.  In the meantime, when
we rotate our service keys, the authorizer doesn't get updated.  Eventually
it will be rejected by the server on a new connection attempt and get
invalidated, and we will then rebuild a new authorizer, but this is not
ideal.

Instead, if we do have an authorizer, call a new update_authorizer op that
will verify that the current authorizer is using the latest secret.  If it
is not, we will build a new one that does.  This avoids the transient
failure.

This fixes one of the sorry sequence of events for bug

	http://tracker.ceph.com/issues/4282

Signed-off-by: Sage Weil 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

kmsg: honor dmesg_restrict sysctl on /dev/kmsg

2013-06-20T19:01:29+00:00

commit 637241a900cbd982f744d44646b48a273d609b34 upstream.

The dmesg_restrict sysctl currently covers the syslog method for access
dmesg, however /dev/kmsg isn't covered by the same protections.  Most
people haven't noticed because util-linux dmesg(1) defaults to using the
syslog method for access in older versions.  With util-linux dmesg(1)
defaults to reading directly from /dev/kmsg.

To fix /dev/kmsg, let's compare the existing interfaces and what they
allow:

 - /proc/kmsg allows:
  - open (SYSLOG_ACTION_OPEN) if CAP_SYSLOG since it uses a destructive
    single-reader interface (SYSLOG_ACTION_READ).
  - everything, after an open.

 - syslog syscall allows:
  - anything, if CAP_SYSLOG.
  - SYSLOG_ACTION_READ_ALL and SYSLOG_ACTION_SIZE_BUFFER, if
    dmesg_restrict==0.
  - nothing else (EPERM).

The use-cases were:
 - dmesg(1) needs to do non-destructive SYSLOG_ACTION_READ_ALLs.
 - sysklog(1) needs to open /proc/kmsg, drop privs, and still issue the
   destructive SYSLOG_ACTION_READs.

AIUI, dmesg(1) is moving to /dev/kmsg, and systemd-journald doesn't
clear the ring buffer.

Based on the comments in devkmsg_llseek, it sounds like actions besides
reading aren't going to be supported by /dev/kmsg (i.e.
SYSLOG_ACTION_CLEAR), so we have a strict subset of the non-destructive
syslog syscall actions.

To this end, move the check as Josh had done, but also rename the
constants to reflect their new uses (SYSLOG_FROM_CALL becomes
SYSLOG_FROM_READER, and SYSLOG_FROM_FILE becomes SYSLOG_FROM_PROC).
SYSLOG_FROM_READER allows non-destructive actions, and SYSLOG_FROM_PROC
allows destructive actions after a capabilities-constrained
SYSLOG_ACTION_OPEN check.

 - /dev/kmsg allows:
  - open if CAP_SYSLOG or dmesg_restrict==0
  - reading/polling, after open

Addresses https://bugzilla.redhat.com/show_bug.cgi?id=903192

[akpm@linux-foundation.org: use pr_warn_once()]
Signed-off-by: Kees Cook 
Reported-by: Christian Kujau 
Tested-by: Josh Boyer 
Cc: Kay Sievers 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ceph: ceph_pagelist_append might sleep while atomic

2013-06-20T19:01:27+00:00

commit 39be95e9c8c0b5668c9f8806ffe29bf9f4bc0f40 upstream.

Ceph's encode_caps_cb() worked hard to not call __page_cache_alloc()
while holding a lock, but it's spoiled because ceph_pagelist_addpage()
always calls kmap(), which might sleep.  Here's the result:

[13439.295457] ceph: mds0 reconnect start
[13439.300572] BUG: sleeping function called from invalid context at include/linux/highmem.h:58
[13439.309243] in_atomic(): 1, irqs_disabled(): 0, pid: 12059, name: kworker/1:1
    . . .
[13439.376225] Call Trace:
[13439.378757]  [] __might_sleep+0xfc/0x110
[13439.384353]  [] ceph_pagelist_append+0x120/0x1b0 [libceph]
[13439.391491]  [] ceph_encode_locks+0x89/0x190 [ceph]
[13439.398035]  [] ? _raw_spin_lock+0x49/0x50
[13439.403775]  [] ? lock_flocks+0x15/0x20
[13439.409277]  [] encode_caps_cb+0x41f/0x4a0 [ceph]
[13439.415622]  [] ? igrab+0x28/0x70
[13439.420610]  [] ? iterate_session_caps+0xe8/0x250 [ceph]
[13439.427584]  [] iterate_session_caps+0x115/0x250 [ceph]
[13439.434499]  [] ? set_request_path_attr+0x2d0/0x2d0 [ceph]
[13439.441646]  [] send_mds_reconnect+0x238/0x450 [ceph]
[13439.448363]  [] ? ceph_mdsmap_decode+0x5e2/0x770 [ceph]
[13439.455250]  [] check_new_map+0x352/0x500 [ceph]
[13439.461534]  [] ceph_mdsc_handle_map+0x1bd/0x260 [ceph]
[13439.468432]  [] ? mutex_unlock+0xe/0x10
[13439.473934]  [] extra_mon_dispatch+0x22/0x30 [ceph]
[13439.480464]  [] dispatch+0xbc/0x110 [libceph]
[13439.486492]  [] process_message+0x1ad/0x1d0 [libceph]
[13439.493190]  [] ? read_partial_message+0x3e8/0x520 [libceph]
    . . .
[13439.587132] ceph: mds0 reconnect success
[13490.720032] ceph: mds0 caps stale
[13501.235257] ceph: mds0 recovery completed
[13501.300419] ceph: mds0 caps renewed

Fix it up by encoding locks into a buffer first, and when the number
of encoded locks is stable, copy that into a ceph_pagelist.

[elder@inktank.com: abbreviated the stack info a bit.]

Signed-off-by: Jim Schutt 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

ceph: add cpu_to_le32() calls when encoding a reconnect capability

2013-06-20T19:01:27+00:00

commit c420276a532a10ef59849adc2681f45306166b89 upstream.

In his review, Alex Elder mentioned that he hadn't checked that
num_fcntl_locks and num_flock_locks were properly decoded on the
server side, from a le32 over-the-wire type to a cpu type.
I checked, and AFAICS it is done; those interested can consult
    Locker::_do_cap_update()
in src/mds/Locker.cc and src/include/encoding.h in the Ceph server
code (git://github.com/ceph/ceph).

I also checked the server side for flock_len decoding, and I believe
that also happens correctly, by virtue of having been declared
__le32 in struct ceph_mds_cap_reconnect, in src/include/ceph_fs.h.

Signed-off-by: Jim Schutt 
Reviewed-by: Alex Elder 
Signed-off-by: Greg Kroah-Hartman

eCryptfs: Check return of filemap_write_and_wait during fsync

2013-06-13T17:49:32+00:00

commit bc5abcf7e411b889f73ea2a90439071a0f451011 upstream.

Error out of ecryptfs_fsync() if filemap_write_and_wait() fails.

Signed-off-by: Tyler Hicks 
Cc: Paul Taysom 
Cc: Olof Johansson 
Signed-off-by: Greg Kroah-Hartman

ecryptfs: fixed msync to flush data

2013-06-13T17:49:31+00:00

commit c15cddd900e867c5adfb3c79596479dc5975f743 upstream.

When msync is called on a memory mapped file, that
data is not flushed to the disk.

In Linux, msync calls fsync for the file. For ecryptfs,
fsync just calls the lower level file system's fsync.
Changed the ecryptfs fsync code to call filemap_write_and_wait
before calling the lower level fsync.

Addresses the problem described in http://crbug.com/239536

Signed-off-by: Paul Taysom 
Signed-off-by: Tyler Hicks 
Signed-off-by: Greg Kroah-Hartman

cifs: fix off-by-one bug in build_unc_path_to_root

2013-06-13T17:49:31+00:00

commit 1fc29bacedeabb278080e31bb9c1ecb49f143c3b upstream.

commit 839db3d10a (cifs: fix up handling of prefixpath= option) changed
the code such that the vol->prepath no longer contained a leading
delimiter and then fixed up the places that accessed that field to
account for that change.

One spot in build_unc_path_to_root was missed however. When doing the
pointer addition on pos, that patch failed to account for the fact that
we had already incremented "pos" by one when adding the length of the
prepath. This caused a buffer overrun by one byte.

This patch fixes the problem by correcting the handling of "pos".

Reported-by: Marcus Moeller 
Reported-by: Ken Fallon 
Signed-off-by: Jeff Layton 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

hpfs: fix warnings when the filesystem fills up

2013-06-13T17:49:30+00:00

commit bbd465df73f0d8ba41b8a0732766a243d0f5b356 upstream.

This patch fixes warnings due to missing lock on write error path.

  WARNING: at fs/hpfs/hpfs_fn.h:353 hpfs_truncate+0x75/0x80 [hpfs]()
  Hardware name: empty
  Pid: 26563, comm: dd Tainted: P           O 3.9.4 #12
  Call Trace:
    hpfs_truncate+0x75/0x80 [hpfs]
    hpfs_write_begin+0x84/0x90 [hpfs]
    _hpfs_bmap+0x10/0x10 [hpfs]
    generic_file_buffered_write+0x121/0x2c0
    __generic_file_aio_write+0x1c7/0x3f0
    generic_file_aio_write+0x7c/0x100
    do_sync_write+0x98/0xd0
    hpfs_file_write+0xd/0x50 [hpfs]
    vfs_write+0xa2/0x160
    sys_write+0x51/0xa0
    page_fault+0x22/0x30
    system_call_fastpath+0x1a/0x1f

Signed-off-by: Mikulas Patocka 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

fuse: fix readdirplus Oops in fuse_dentry_revalidate

2013-06-07T19:53:35+00:00

commit 28420dad233520811c0e0860e7fb4975ed863fc4 upstream.

Fix bug introduced by commit 4582a4ab2a "FUSE: Adapt readdirplus to application
usage patterns".

We need to check for a positive dentry; negative dentries are not added by
readdirplus.  Secondly we need to advise the use of readdirplus on the *parent*,
otherwise the whole thing is useless.  Thirdly all this is only relevant if
"readdirplus_auto" mode is selected by the filesystem.

We advise the use of readdirplus only if the dentry was still valid.  If we had
to redo the lookup then there was no use in doing the -plus version.

Reported-by: Bernd Schubert 
Signed-off-by: Miklos Szeredi 
CC: Feng Shuo 
Signed-off-by: Greg Kroah-Hartman