A process can have two possible lock owner for a given open file:
a per-process Posix lock owner and a per-open-file flock owner
Use both of these when searching for a suitable stateid to use.
With this patch, READ/WRITE requests will use the correct stateid
if a flock lock is active.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The only time that a lock_context is not immediately available is in
setattr, and now that it has an open_context, it can easily find one
with nfs_get_lock_context.
This removes the need for the on-stack nfs_lockowner.
This change is preparation for correctly support flock stateids.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The open_context can always lead directly to the state, and is always easily
available, so this is a straightforward change.
Doing this makes more information available to _nfs4_do_setattr() for use
in the next patch.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
An open file description (struct file) in a given process can be
associated with two different lock owners.
It can have a Posix lock owner which will be different in each process
that has a fd on the file.
It can have a Flock owner which will be the same in all processes.
When searching for a lock stateid to use, we need to consider both of these
owners
So add a new "flock_owner" to the "nfs_open_context" (of which there
is one for each open file description).
This flock_owner does not need to be reference-counted as there is a
1-1 relation between 'struct file' and nfs open contexts,
and it will never be part of a list of contexts. So there is no need
for a 'flock_context' - just the owner is enough.
The io_count included in the (Posix) lock_context provides no
guarantee that all read-aheads that could use the state have
completed, so not supporting it for flock locks in not a serious
problem. Synchronization between flock and read-ahead can be added
later if needed.
When creating an open_context for a non-openning create call, we don't have
a 'struct file' to pass in, so the lock context gets initialized with
a NULL owner, but this will never be used.
The flock_owner is not used at all in this patch, that will come later.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
this field is not used in any important way and probably should
have been removed by
Commit: 8003d3c4aa ("nfs4: treat lock owners as opaque values")
which removed the pid argument from nfs4_get_lock_state.
Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It's possible that two different servers can return the same (clientid,
verifier) pair purely by coincidence. Both are 64-bit values, but
depending on the server implementation, they can be highly predictable
and collisions may be quite likely, especially when there are lots of
servers.
So, check for this case. If the clientid and verifier both match, then
we actually know they *can't* be the same server, since a new
SETCLIENTID to an already-known server should have changed the verifier.
This helps fix a bug that could cause the client to mount a filesystem
from the wrong server.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Yongcheng Yang <yoyang@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ensure that the layout state bits are synced when we cache a layout
segment for layoutreturn using an appropriate call to
pnfs_set_plh_return_info.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We need to honour the NFS_LAYOUT_RETURN_REQUESTED bit regardless of
whether or not there are layout segments pending.
Furthermore, we should ensure that we leave the plh_return_segs list
empty.
This patch fixes a memory leak of the layout segments on plh_return_segs.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When the layout state is invalidated, then so is the layout segment
state, and hence we do need to clean up the state bits.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we cannot grab the inode or superblock, then we cannot pin the
layout header, and so we cannot send a layoutreturn as part of an
async delegreturn call. In this case, we currently end up sending
an extra layoutreturn after the delegreturn. Since the layout was
implicitly returned by the delegreturn, that just gets a BAD_STATEID.
The fix is to simply complete the return-on-close immediately.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Amend the pnfs return on close helper functions to enable sending the
layoutreturn op in CLOSE/DELEGRETURN. This closes a potential race between
CLOSE/DELEGRETURN and parallel OPEN calls to the same file, and allows the
client and the server to agree on whether or not there is an outstanding
layout.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the DELEGRETURN compound.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the CLOSE compound.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The layoutreturn call will take care of invalidating the layout segments
once the call is successful.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There is no change to the value of NFS_LAYOUT_RETURN, so we should
not be waking up the RPC call.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fix a potential race with CB_LAYOUTRECALL in which the server recalls the
remaining layout segments while our LAYOUTRETURN is still in transit.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We may want to process and transmit layout stat information for the
layout segments that are being returned, so we should defer freeing
them until after the layoutreturn has completed.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead of grabbing the layout, we want to get the inode so that we
can reduce races between layoutget and layoutrecall when the server
does not support call referring.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Both pnfs.c and the flexfiles code have their own versions of the
range intersection testing, and the "end_offset" helper.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We must put the task to sleep while holding the inode->i_lock in order
to ensure atomicity with the test for NFS_LAYOUT_RETURN.
Fixes: 500d701f33 ("NFS41: make close wait for layoutreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If there is an I/O error, we should not call LAYOUTGET until the
LAYOUTRETURN that reports the error is complete.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v4.8+
If the server sends us a completely new stateid, and the client thinks
it already holds a layout, then force a retry of the LAYOUTGET after
invalidating the existing layout in order to avoid corruption due to
races.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We must ensure that we don't schedule a layoutreturn if the layout stateid
has been marked as invalid.
Fixes: 2a59a04116 ("pNFS: Fix pnfs_set_layout_stateid() to clear...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v4.8+
If we no longer hold any layout segments, we're normally expected to
consider the layout stateid to be invalid. However we cannot assume this
if we're about to, or in the process of sending a layoutreturn.
Fixes: 334a8f3711 ("pNFS: Don't forget the layout stateid if...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v4.8+
We must not call nfs_pageio_init_read() on a new nfs_pageio_descriptor
while holding a reference to a layout segment, as that can deadlock
pnfs_update_layout().
Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v4.0+
When initializing a freshly created slot for the calllback channel,
the seq_nr needs to be 0, not 1. Otherwise validate_seqid
and nfs4_slot_wait_on_seqid get confused and believe that the
mpty slot corresponds to a previously sent reply.
Signed-off-by: Fred Isaman <fred.isaman@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The NFS_INO_REVAL_FORCED flag needs to be set if we just got a delegation,
and we see that there might still be some ambiguity as to whether or not
our attribute or data cache are valid.
In practice, this means that a call to nfs_check_inode_attributes() will
have noticed a discrepancy between cached attributes and measured ones,
so let's move the setting of NFS_INO_REVAL_FORCED to there.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If holding a delegation, we do not need to ask the server to return
close-to-open cache consistency attributes as part of the CLOSE
compound.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we're not closing the file completely, there is no need to request
close-to-open attributes.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
We don't need to ask for the change attribute when returning a delegation
or recovering from a server reboot, and it could actually cause us to
obtain an incorrect value if we're using a pNFS flavour that requires
LAYOUTCOMMIT.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we're reclaiming state after a reboot, or as part of returning a
delegation, we don't need to check access modes again.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ralf Spenneberg reported that he hit a kernel crash when mounting a
modified ext4 image. And it turns out that kernel crashed when
calculating fs overhead (ext4_calculate_overhead()), this is because
the image has very large s_first_meta_bg (debug code shows it's
842150400), and ext4 overruns the memory in count_overhead() when
setting bitmap buffer, which is PAGE_SIZE.
ext4_calculate_overhead():
buf = get_zeroed_page(GFP_NOFS); <=== PAGE_SIZE buffer
blks = count_overhead(sb, i, buf);
count_overhead():
for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) { <=== j = 842150400
ext4_set_bit(EXT4_B2C(sbi, s++), buf); <=== buffer overrun
count++;
}
This can be reproduced easily for me by this script:
#!/bin/bash
rm -f fs.img
mkdir -p /mnt/ext4
fallocate -l 16M fs.img
mke2fs -t ext4 -O bigalloc,meta_bg,^resize_inode -F fs.img
debugfs -w -R "ssv first_meta_bg 842150400" fs.img
mount -o loop fs.img /mnt/ext4
Fix it by validating s_first_meta_bg first at mount time, and
refusing to mount if its value exceeds the largest possible meta_bg
number.
Reported-by: Ralf Spenneberg <ralf@os-t.de>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
It was possible for an xattr value to have a very large size, which
would then pass validation on 32-bit architectures due to a pointer
wraparound. Fix this by validating the size in a way which avoids
pointer wraparound.
It was also possible that a value's size would fit in the available
space but its padded size would not. This would cause an out-of-bounds
memory write in ext4_xattr_set_entry when replacing the xattr value.
For example, if an xattr value of unpadded size 253 bytes went until the
very end of the inode or block, then using setxattr(2) to replace this
xattr's value with 256 bytes would cause a write to the 3 bytes past the
end of the inode or buffer, and the new xattr value would be incorrectly
truncated. Fix this by requiring that the padded size fit in the
available space rather than the unpadded size.
This patch shouldn't have any noticeable effect on
non-corrupted/non-malicious filesystems.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
With i_extra_isize equal to or close to the available space, it was
possible for us to read past the end of the inode when trying to detect
or validate in-inode xattrs. Fix this by checking for the needed extra
space first.
This patch shouldn't have any noticeable effect on
non-corrupted/non-malicious filesystems.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
i_extra_isize not divisible by 4 is problematic for several reasons:
- It causes the in-inode xattr space to be misaligned, but the xattr
header and entries are not declared __packed to express this
possibility. This may cause poor performance or incorrect code
generation on some platforms.
- When validating the xattr entries we can read past the end of the
inode if the size available for xattrs is not a multiple of 4.
- It allows the nonsensical i_extra_isize=1, which doesn't even leave
enough room for i_extra_isize itself.
Therefore, update ext4_iget() to consider i_extra_isize not divisible by
4 to be an error, like the case where i_extra_isize is too large.
This also matches the rule recently added to e2fsck for determining
whether an inode has valid i_extra_isize.
This patch shouldn't have any noticeable effect on
non-corrupted/non-malicious filesystems, since the size of ext4_inode
has always been a multiple of 4.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Pull overlayfs fix from Miklos Szeredi:
"This fixes a regression introduced in 4.8"
* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: fix d_real() for stacked fs
On a CONFIG_EXT4_FS_ENCRYPTION=n kernel, the ioctls to get and set
encryption policies were disabled but EXT4_IOC_GET_ENCRYPTION_PWSALT was
not. But there's no good reason to expose the pwsalt ioctl if the
kernel doesn't support encryption. The pwsalt ioctl was also disabled
pre-4.8 (via ext4_sb_has_crypto() previously returning 0 when encryption
was disabled by config) and seems to have been enabled by mistake when
ext4 encryption was refactored to use fs/crypto/. So let's disable it
again.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_sb_has_crypto() just called through to ext4_has_feature_encrypt(),
and all callers except one were already using the latter. So remove it
and switch its one caller to ext4_has_feature_encrypt().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We've fixed the race condition problem in calculating ext4 checksum
value in commit b47820edd1 ("ext4: avoid modifying checksum fields
directly during checksum veficationon"). However, by this change,
when calculating the checksum value of inode whose i_extra_size is
less than 4, we couldn't calculate the checksum value in a proper way.
This problem was found and reported by Nix, Thank you.
Reported-by: Nix <nix@esperi.org.uk>
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Warn when a page is dirtied without buffers (as that will likely lead to
a crash in ext4_writepages()) or when it gets newly dirtied without the
page being locked (as there is nothing that prevents buffers to get
stripped just before calling set_page_dirty() under memory pressure).
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
