linux-stable.git/fs/reiserfs, branch linux-3.6.y

reiserfs: Protect reiserfs_quota_write() with write lock

2012-11-26T20:14:21+00:00

commit 361d94a338a3fd0cee6a4ea32bbc427ba228e628 upstream.

Calls into reiserfs journalling code and reiserfs_get_block() need to
be protected with write lock. We remove write lock around calls to high
level quota code in the next patch so these paths would suddently become
unprotected.

Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

reiserfs: Move quota calls out of write lock

2012-11-26T20:14:21+00:00

commit 7af11686933726e99af22901d622f9e161404e6b upstream.

Calls into highlevel quota code cannot happen under the write lock. These
calls take dqio_mutex which ranks above write lock. So drop write lock
before calling back into quota code.

Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

reiserfs: Protect reiserfs_quota_on() with write lock

2012-11-26T20:14:21+00:00

commit b9e06ef2e8706fe669b51f4364e3aeed58639eb2 upstream.

In reiserfs_quota_on() we do quite some work - for example unpacking
tail of a quota file. Thus we have to hold write lock until a moment
we call back into the quota code.

Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

reiserfs: Fix lock ordering during remount

2012-11-26T20:14:21+00:00

commit 3bb3e1fc47aca554e7e2cc4deeddc24750987ac2 upstream.

When remounting reiserfs dquot_suspend() or dquot_resume() can be called.
These functions take dqonoff_mutex which ranks above write lock so we have
to drop it before calling into quota code.

Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checking

2012-10-21T16:32:39+00:00

commit 35c2a7f4908d404c9124c2efc6ada4640ca4d5d5 upstream.

Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(),
	u64 inum = fid->raw[2];
which is unhelpfully reported as at the end of shmem_alloc_inode():

BUG: unable to handle kernel paging request at ffff880061cd3000
IP: [] shmem_alloc_inode+0x40/0x40
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Call Trace:
 [] ? exportfs_decode_fh+0x79/0x2d0
 [] do_handle_open+0x163/0x2c0
 [] sys_open_by_handle_at+0xc/0x10
 [] tracesys+0xe1/0xe6

Right, tmpfs is being stupid to access fid->raw[2] before validating that
fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may
fall at the end of a page, and the next page not be present.

But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being
careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and
could oops in the same way: add the missing fh_len checks to those.

Reported-by: Sasha Levin 
Signed-off-by: Hugh Dickins 
Cc: Al Viro 
Cc: Sage Weil 
Cc: Steven Whitehouse 
Cc: Christoph Hellwig 
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

reiserfs: fix deadlocks with quotas

2012-08-14T22:22:57+00:00

The BKL push-down for reiserfs made lock recursion a special case that needs
to be handled explicitly. One of the cases that was unhandled is dropping
the quota during inode eviction. Both reiserfs_evict_inode and
reiserfs_write_dquot take the write lock, but when the journal lock is
taken it only drops one the references. The locking rules are that the journal
lock be acquired before the write lock so leaving the reference open leads
to a ABBA deadlock.

This patch pushes the unlock up before clear_inode and avoids the recursive
locking.

Another ABBA situation can occur when the write lock is dropped while reading
the bitmap buffer while in the quota code. When the lock is reacquired, it
will deadlock against dquot->dq_lock and dqopt->dqio_mutex in the dquot_acquire
path. It's safe to retain the lock across the read and should be cached under
write load.

Signed-off-by: Jeff Mahoney 
Signed-off-by: Jan Kara

don't expose I_NEW inodes via dentry->d_inode

2012-07-22T20:00:58+00:00

	d_instantiate(dentry, inode);
	unlock_new_inode(inode);

is a bad idea; do it the other way round...

Signed-off-by: Al Viro

quota: Move quota syncing to ->sync_fs method

2012-07-22T19:58:34+00:00

Since the moment writes to quota files are using block device page cache and
space for quota structures is reserved at the moment they are first accessed we
have no reason to sync quota before inode writeback. In fact this order is now
only harmful since quota information can easily change during inode writeback
(either because conversion of delayed-allocated extents or simply because of
allocation of new blocks for simple filesystems not using page_mkwrite).

So move syncing of quota information after writeback of inodes into ->sync_fs
method. This way we do not have to use ->quota_sync callback which is primarily
intended for use by quotactl syscall anyway and we get rid of calling
->sync_fs() twice unnecessarily. We skip quota syncing for OCFS2 since it does
proper quota journalling in all cases (unlike ext3, ext4, and reiserfs which
also support legacy non-journalled quotas) and thus there are no dirty quota
structures.

CC: "Theodore Ts'o" 
CC: Joel Becker 
CC: reiserfs-devel@vger.kernel.org
Acked-by: Steven Whitehouse 
Acked-by: Dave Kleikamp 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jan Kara 
Signed-off-by: Al Viro

VFS: Pass mount flags to sget()

2012-07-14T12:38:34+00:00

Pass mount flags to sget() so that it can use them in initialising a new
superblock before the set function is called.  They could also be passed to the
compare function.

Signed-off-by: David Howells 
Signed-off-by: Al Viro

don't pass nameidata to ->create()

2012-07-14T12:34:47+00:00

boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro