linux-stable.git/fs/ocfs2, branch linux-4.3.y

ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup

2016-02-19T22:28:25+00:00

commit c95a51807b730e4681e2ecbdfd669ca52601959e upstream.

When recovery master down, dlm_do_local_recovery_cleanup() only remove
the $RECOVERY lock owned by dead node, but do not clear the refmap bit.
Which will make umount thread falling in dead loop migrating $RECOVERY
to the dead node.

Signed-off-by: xuejiufei 
Reviewed-by: Joseph Qi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2/dlm: ignore cleaning the migration mle that is inuse

2016-02-19T22:28:25+00:00

commit bef5502de074b6f6fa647b94b73155d675694420 upstream.

We have found that migration source will trigger a BUG that the refcount
of mle is already zero before put when the target is down during
migration.  The situation is as follows:

dlm_migrate_lockres
  dlm_add_migration_mle
  dlm_mark_lockres_migrating
  dlm_get_mle_inuse
  <<<<<< Now the refcount of the mle is 2.
  dlm_send_one_lockres and wait for the target to become the
  new master.
  <<<<<< o2hb detect the target down and clean the migration
  mle. Now the refcount is 1.

dlm_migrate_lockres woken, and put the mle twice when found the target
goes down which trigger the BUG with the following message:

  "ERROR: bad mle: ".

Signed-off-by: Jiufei Xue 
Reviewed-by: Joseph Qi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: fix BUG when calculate new backup super

2016-02-19T22:28:25+00:00

commit 5c9ee4cbf2a945271f25b89b137f2c03bbc3be33 upstream.

When resizing, it firstly extends the last gd.  Once it should backup
super in the gd, it calculates new backup super and update the
corresponding value.

But it currently doesn't consider the situation that the backup super is
already done.  And in this case, it still sets the bit in gd bitmap and
then decrease from bg_free_bits_count, which leads to a corrupted gd and
trigger the BUG in ocfs2_block_group_set_bits:

    BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);

So check whether the backup super is done and then do the updates.

Signed-off-by: Joseph Qi 
Reviewed-by: Jiufei Xue 
Reviewed-by: Yiwen Jiang 
Cc: Mark Fasheh 
Cc: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: fix SGID not inherited issue

2016-02-19T22:28:25+00:00

commit 854ee2e944b4daf795e32562a7d2f9e90ab5a6a8 upstream.

Commit 8f1eb48758aa ("ocfs2: fix umask ignored issue") introduced an
issue, SGID of sub dir was not inherited from its parents dir.  It is
because SGID is set into "inode->i_mode" in ocfs2_get_init_inode(), but
is overwritten by "mode" which don't have SGID set later.

Fixes: 8f1eb48758aa ("ocfs2: fix umask ignored issue")
Signed-off-by: Junxiao Bi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Acked-by: Srinivas Eeda 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock

2016-02-19T22:28:23+00:00

commit b1b1e15ef6b80facf76d6757649dfd7295eda29f upstream.

NFS on a 2 node ocfs2 cluster each node exporting dir.  The lock causing
the hang is the global bit map inode lock.  Node 1 is master, has the
lock granted in PR mode; Node 2 is in the converting list (PR -> EX).
There are no holders of the lock on the master node so it should
downconvert to NL and grant EX to node 2 but that does not happen.
BLOCKED + QUEUED in lock res are set and it is on osb blocked list.
Threads are waiting in __ocfs2_cluster_lock on BLOCKED.  One thread
wants EX, rest want PR.  So it is as though the downconvert thread needs
to be kicked to complete the conv.

The hang is caused by an EX req coming into __ocfs2_cluster_lock on the
heels of a PR req after it sets BUSY (drops l_lock, releasing EX
thread), forcing the incoming EX to wait on BUSY without doing anything.
PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> PR,
queues ast.

At this time, upconvert (PR ->EX) arrives from node 2, finds conflict
with node 1 lock in PR, so the lock res is put on dlm thread's dirty
listt.

After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till
awoken by ast.

Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, in
that order.  dlm_shuffle_lists ques a bast on behalf of node 2 (which
will be run by dlm_thread right after the ast).  ast does its part, sets
UPCONVERT_FINISHING, clears BUSY and wakes its waiters.  Next,
dlm_thread runs bast.  It sets BLOCKED and kicks dc thread.  dc thread
runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing
anything and reques.

Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead
of PR, it wakes up first, finds BLOCKED set and skips doing anything but
clearing UPCONVERT_FINISHING (which was actually "meant" for the PR
thread), and this time waits on BLOCKED.  Next, the PR thread comes out
of wait but since UPCONVERT_FINISHING is not set, it skips updating the
l_ro_holders and goes straight to wait on BLOCKED.  So there, we have a
hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock res in osb
blocked list.  Only when dc thread is awoken, it will run
ocfs2_unblock_lock and things will unhang.

One way to fix this is to wake the dc thread on the flag after clearing
UPCONVERT_FINISHING

Orabug: 20933419
Signed-off-by: Tariq Saeed 
Signed-off-by: Santosh Shilimkar 
Reviewed-by: Wengang Wang 
Reviewed-by: Mark Fasheh 
Cc: Joel Becker 
Cc: Junxiao Bi 
Reviewed-by: Joseph Qi 
Cc: Eric Ren 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2: fix umask ignored issue

2015-12-15T05:41:09+00:00

commit 8f1eb48758aacf6c1ffce18179295adbf3bd7640 upstream.

New created file's mode is not masked with umask, and this makes umask not
work for ocfs2 volume.

Fixes: 702e5bc ("ocfs2: use generic posix ACL infrastructure")
Signed-off-by: Junxiao Bi 
Cc: Gang He 
Cc: Mark Fasheh 
Cc: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ocfs2/dlm: unlock lockres spinlock before dlm_lockres_put

2015-10-23T08:55:10+00:00

dlm_lockres_put will call dlm_lockres_release if it is the last
reference, and then it may call dlm_print_one_lock_resource and
take lockres spinlock.

So unlock lockres spinlock before dlm_lockres_put to avoid deadlock.

Signed-off-by: Joseph Qi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

ocfs2/dlm: fix deadlock when dispatch assert master

2015-09-22T22:09:53+00:00

The order of the following three spinlocks should be:
dlm_domain_lock < dlm_ctxt->spinlock < dlm_lock_resource->spinlock

But dlm_dispatch_assert_master() is called while holding
dlm_ctxt->spinlock and dlm_lock_resource->spinlock, and then it calls
dlm_grab() which will take dlm_domain_lock.

Once another thread (for example, dlm_query_join_handler) has already
taken dlm_domain_lock, and tries to take dlm_ctxt->spinlock deadlock
happens.

Signed-off-by: Joseph Qi 
Cc: Joel Becker 
Cc: Mark Fasheh 
Cc: "Junxiao Bi" 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"

2015-09-11T22:21:34+00:00

Revert commit f83c7b5e9fd6 ("ocfs2/dlm: use list_for_each_entry instead
of list_for_each").

list_for_each_entry() will dereference its `pos' argument, which can be
NULL in dlm_process_recovery_data().

Reported-by: Julia Lawall 
Reported-by: Fengguang Wu 
Cc: Joseph Qi 
Cc: Mark Fasheh 
Cc: Joel Becker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs: create and use seq_show_option for escaping

2015-09-04T23:54:41+00:00

Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook 
Acked-by: Serge Hallyn 
Acked-by: Jan Kara 
Acked-by: Paul Moore 
Cc: J. R. Okajima 
Signed-off-by: Kees Cook 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds