Commit Graph

47524 Commits

Author SHA1 Message Date
Jaegeuk Kim
67c3758d22 f2fs: call update_inode_page for orphan inodes
Let's store orphan inode pages right away.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-07-06 10:44:07 -07:00
Jaegeuk Kim
3e19886eda f2fs: report error for f2fs_parent_dir
If there is no dentry, we can report its error correctly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2016-07-06 10:44:06 -07:00
David S. Miller
30d0844bdc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/mellanox/mlx5/core/en.h
	drivers/net/ethernet/mellanox/mlx5/core/en_main.c
	drivers/net/usb/r8152.c

All three conflicts were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-06 10:35:22 -07:00
Carlos Maiolino
ff0031d848 ext2: fix filesystem deadlock while reading corrupted xattr block
This bug can be reproducible with fsfuzzer, although, I couldn't reproduce it
100% of my tries, it is quite easily reproducible.

During the deletion of an inode, ext2_xattr_delete_inode() does not check if the
block pointed by EXT2_I(inode)->i_file_acl is a valid data block, this might
lead to a deadlock, when i_file_acl == 1, and the filesystem block size is 1024.

In that situation, ext2_xattr_delete_inode, will load the superblock's buffer
head (instead of a valid i_file_acl block), and then lock that buffer head,
which, ext2_sync_super will also try to lock, making the filesystem deadlock in
the following stack trace:

root     17180  0.0  0.0 113660   660 pts/0    D+   07:08   0:00 rmdir
/media/test/dir1

[<ffffffff8125da9f>] __sync_dirty_buffer+0xaf/0x100
[<ffffffff8125db03>] sync_dirty_buffer+0x13/0x20
[<ffffffffa03f0d57>] ext2_sync_super+0xb7/0xc0 [ext2]
[<ffffffffa03f10b9>] ext2_error+0x119/0x130 [ext2]
[<ffffffffa03e9d93>] ext2_free_blocks+0x83/0x350 [ext2]
[<ffffffffa03f3d03>] ext2_xattr_delete_inode+0x173/0x190 [ext2]
[<ffffffffa03ee9e9>] ext2_evict_inode+0xc9/0x130 [ext2]
[<ffffffff8123fd23>] evict+0xb3/0x180
[<ffffffff81240008>] iput+0x1b8/0x240
[<ffffffff8123c4ac>] d_delete+0x11c/0x150
[<ffffffff8122fa7e>] vfs_rmdir+0xfe/0x120
[<ffffffff812340ee>] do_rmdir+0x17e/0x1f0
[<ffffffff81234dd6>] SyS_rmdir+0x16/0x20
[<ffffffff81838cf2>] entry_SYSCALL_64_fastpath+0x1a/0xa4
[<ffffffffffffffff>] 0xffffffffffffffff

Fix this by using the same approach ext4 uses to test data blocks validity,
implementing ext2_data_block_valid.

An another possibility when the superblock is very corrupted, is that i_file_acl
is 1, block_count is 1 and first_data_block is 0. For such situations, we might
have i_file_acl pointing to a 'valid' block, but still step over the superblock.
The approach I used was to also test if the superblock is not in the range
described by ext2_data_block_valid() arguments

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-07-05 22:02:41 -04:00
Wang Shilong
079788d01e ext4: fix project quota accounting without quota limits enabled
We should always transfer quota accounting, regardless of whether
quota limits are enabled.

Steps to reproduce:
  # mkfs.ext4 /dev/sda4 -O quota,project
  # mount /dev/sda4 /mnt/test
  # cp /bin/bash /mnt/test
  # chattr -p 123 /mnt/test/bash
  # quota -v -P 123

Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-07-05 21:33:52 -04:00
Theodore Ts'o
5b9554dc5b ext4: validate s_reserved_gdt_blocks on mount
If s_reserved_gdt_blocks is extremely large, it's possible for
ext4_init_block_bitmap(), which is called when ext4 sets up an
uninitialized block bitmap, to corrupt random kernel memory.  Add the
same checks which e2fsck has --- it must never be larger than
blocksize / sizeof(__u32) --- and then add a backup check in
ext4_init_block_bitmap() in case the superblock gets modified after
the file system is mounted.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2016-07-05 20:01:52 -04:00
Trond Myklebust
9a773e7c8d NFS nfs_vm_page_mkwrite: Don't freeze me, Bro...
Prevent filesystem freezes while handling the write page fault.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:08 -04:00
Trond Myklebust
e95fc4a069 NFSv4.2: llseek(SEEK_HOLE) and llseek(SEEK_DATA) don't require data sync
We want to ensure that we write the cached data to the server, but
don't require it be synced to disk. If the server reboots, we will
get a stateid error, which will cause us to retry anyway.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:08 -04:00
Trond Myklebust
837bb1d752 NFSv4.2: Fix writeback races in nfs4_copy_file_range
We need to ensure that any writes to the destination file are serialised
with the copy, meaning that the writeback has to occur under the inode lock.

Also relax the writeback requirement on the source, and rely on the
stateid checking to tell us if the source rebooted. Add the helper
nfs_filemap_write_and_wait_range() to call pnfs_sync_inode() as
is appropriate for pNFS servers that may need a layoutcommit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:07 -04:00
Trond Myklebust
1e564d3dbd NFSv4.2: Fix a race in nfs42_proc_deallocate()
When punching holes in a file, we want to ensure the operation is
serialised w.r.t. other writes, meaning that we want to call
nfs_sync_inode() while holding the inode lock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:07 -04:00
Trond Myklebust
79566ef018 NFS: Getattr doesn't require data sync semantics
When retrieving stat() information, NFS unfortunately does require us to
sync writes to disk in order to ensure that mtime and ctime are up to
date. However we shouldn't have to ensure that those writes are persisted.

Relaxing that requirement does mean that we may see an mtime/ctime change
if the server reboots and forces us to replay all writes.

The exception to this rule are pNFS clients that are required to send
layoutcommit, however that is dealt with by the call to pnfs_sync_inode()
in _nfs_revalidate_inode().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:06 -04:00
Trond Myklebust
651b0e7029 NFS: Do not aggressively cache file attributes in the case of O_DIRECT
A file that is open for O_DIRECT is by definition not obeying
close-to-open cache consistency semantics, so let's not cache
the attributes too aggressively either.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:06 -04:00
Trond Myklebust
be527494e0 NFS: Remove unused function nfs_revalidate_mapping_protected()
Clean up...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:05 -04:00
Trond Myklebust
f508d46ae4 NFS: Remove redundant waits for O_DIRECT in fsync() and write_begin()
We're now waiting immediately after taking the locks, so waiting
in fsync() and write_begin() is either redundant or potentially
subject to livelock (if not holding the lock).

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:05 -04:00
Trond Myklebust
f7b5c340ac NFS: Cleanup nfs_direct_complete()
There is only one caller that sets the "write" argument to true,
so just move the call to nfs_zap_mapping() and get rid of the
now redundant argument.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust
a5864c999d NFS: Do not serialise O_DIRECT reads and writes
Allow dio requests to be scheduled in parallel, but ensuring that they
do not conflict with buffered I/O.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust
18290650b1 NFS: Move buffered I/O locking into nfs_file_write()
Preparation for the patch that de-serialises O_DIRECT reads and
writes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:03 -04:00
Trond Myklebust
89698b24d2 NFS Cleanup: move call to generic_write_checks() into fs/nfs/direct.c
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:03 -04:00
Trond Myklebust
2f3c7d87a3 NFS: Remove racy size manipulations in O_DIRECT
On success, the RPC callbacks will ensure that we make the appropriate calls
to nfs_writeback_update_inode()

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust
a5314a7492 NFS: Ensure we reset the write verifier 'committed' value on resend.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust
8fc3c38627 NFS: Fix O_DIRECT verifier problems
We should not be interested in looking at the value of the stable field,
since that could take any value.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:01 -04:00
Trond Myklebust
6712007734 pNFS: pnfs_layoutcommit_outstanding() is no longer used when !CONFIG_NFS_V4_1
Cleanup...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:01 -04:00
Trond Myklebust
ac46bd374c pNFS: Ensure we layoutcommit before revalidating attributes
If we need to update the cached attributes, then we'd better make
sure that we also layoutcommit first. Otherwise, the server may have stale
attributes.

Prior to this patch, the revalidation code tried to "fix" this problem by
simply disabling attributes that would be affected by the layoutcommit.
That approach breaks nfs_writeback_check_extend(), leading to a file size
corruption.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:08:27 -04:00
Trond Myklebust
2e18d4d822 pNFS: Files and flexfiles always need to commit before layoutcommit
So ensure that we mark the layout for commit once the write is done,
and then ensure that the commit to ds is finished before sending
layoutcommit.

Note that by doing this, we're able to optimise away the commit
for the case of servers that don't need layoutcommit in order to
return updated attributes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:08:01 -04:00
Trond Myklebust
bc28e1c2e3 pNFS/flexfiles: Clean up calls to pnfs_set_layoutcommit()
Let's just have one place where we check ff_layout_need_layoutcommit().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:26 -04:00
Trond Myklebust
c001c87a63 pNFS/flexfiles: Fix layoutcommit after a commit to DS
We should always do a layoutcommit after commit to DS, except if
the layout segment we're using has set FF_FLAGS_NO_LAYOUTCOMMIT.

Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:26 -04:00
Trond Myklebust
73e6c5d854 pNFS/files: Fix layoutcommit after a commit to DS
According to the errata
https://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
we should always send layout commit after a commit to DS.

Fixes: bc7d4b8fd0 ("nfs/filelayout: set layoutcommit...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:25 -04:00
yalin wang
de9e9181bc ext4: remove unused page_idx
Signed-off-by: yalin wang <yalin.wang2010@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.com>
2016-07-05 16:32:32 -04:00
Eric W. Biederman
5c0048280b dquot: For now explicitly don't support filesystems outside of init_user_ns
Mostly supporting filesystems outside of init_user_ns is
s/&init_usre_ns/dquot->dq_sb->s_user_ns/.  An actual need for
supporting quotas on filesystems outside of s_user_ns is quite a ways
away and to be done responsibily needs an audit on what can happen
with hostile quota files.  Until that audit is complete don't attempt
to support quota files on filesystems outside of s_user_ns.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:12:39 -05:00
Eric W. Biederman
cfd4c70a18 quota: Handle quota data stored in s_user_ns in quota_setxquota
In Q_XSETQLIMIT use sb->s_user_ns to detect when we are dealing with
the filesystems notion of id 0.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Inspired-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:12:20 -05:00
Eric W. Biederman
d49d37624a quota: Ensure qids map to the filesystem
Introduce the helper qid_has_mapping and use it to ensure that the
quota system only considers qids that map to the filesystems
s_user_ns.

In practice for quota supporting filesystems today this is the exact
same check as qid_valid.  As only 0xffffffff aka (qid_t)-1 does not
map into init_user_ns.

Replace the qid_valid calls with qid_has_mapping as values come in
from userspace.  This is harmless today and it prepares the quota
system to work on filesystems with quotas but mounted by unprivileged
users.

Call qid_has_mapping from dqget.  This ensures the passed in qid has a
prepresentation on the underlying filesystem.  Previously this was
unnecessary as filesystesm never had qids that could not map.  With
the introduction of filesystems outside of s_user_ns this will not
remain true.

All of this ensures the quota code never has to deal with qids that
don't map to the underlying filesystem.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:12:05 -05:00
Eric W. Biederman
036d523641 vfs: Don't create inodes with a uid or gid unknown to the vfs
It is expected that filesystems can not represent uids and gids from
outside of their user namespace.  Keep things simple by not even
trying to create filesystem nodes with non-sense uids and gids.

Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:11:47 -05:00
Eric W. Biederman
0bd23d09b8 vfs: Don't modify inodes with a uid or gid unknown to the vfs
When a filesystem outside of init_user_ns is mounted it could have
uids and gids stored in it that do not map to init_user_ns.

The plan is to allow those filesystems to set i_uid to INVALID_UID and
i_gid to INVALID_GID for unmapped uids and gids and then to handle
that strange case in the vfs to ensure there is consistent robust
handling of the weirdness.

Upon a careful review of the vfs and filesystems about the only case
where there is any possibility of confusion or trouble is when the
inode is written back to disk.  In that case filesystems typically
read the inode->i_uid and inode->i_gid and write them to disk even
when just an inode timestamp is being updated.

Which leads to a rule that is very simple to implement and understand
inodes whose i_uid or i_gid is not valid may not be written.

In dealing with access times this means treat those inodes as if the
inode flag S_NOATIME was set.  Reads of the inodes appear safe and
useful, but any write or modification is disallowed.  The only inode
write that is allowed is a chown that sets the uid and gid on the
inode to valid values.  After such a chown the inode is normal and may
be treated as such.

Denying all writes to inodes with uids or gids unknown to the vfs also
prevents several oddball cases where corruption would have occurred
because the vfs does not have complete information.

One problem case that is prevented is attempting to use the gid of a
directory for new inodes where the directories sgid bit is set but the
directories gid is not mapped.

Another problem case avoided is attempting to update the evm hash
after setxattr, removexattr, and setattr.  As the evm hash includeds
the inode->i_uid or inode->i_gid not knowning the uid or gid prevents
a correct evm hash from being computed.  evm hash verification also
fails when i_uid or i_gid is unknown but that is essentially harmless
as it does not cause filesystem corruption.

Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:06:46 -05:00
Al Viro
c94c09535c nfs_atomic_open(): prevent parallel nfs_lookup() on a negative hashed
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:31 -04:00
Al Viro
00699ad857 Use the right predicate in ->atomic_open() instances
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache.  Use d_in_lookup() to tell one from another, rather
than d_unhashed().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:23 -04:00
Jann Horn
78fee0b684 orangefs: fix namespace handling
In orangefs_inode_getxattr(), an fsuid is written to dmesg. The kuid is
converted to a userspace uid via from_kuid(current_user_ns(), [...]), but
since dmesg is global, init_user_ns should be used here instead.

In copy_attributes_from_inode(), op_alloc() and fill_default_sys_attrs(),
upcall structures are populated with uids/gids that have been mapped into
the caller's namespace. However, those upcall structures are read by
another process (the userspace filesystem driver), and that process might
be running in another namespace. This effectively lets any user spoof its
uid and gid as seen by the userspace filesystem driver.

To fix the second issue, I just construct the opcall structures with
init_user_ns uids/gids and require the filesystem server to run in the
init namespace. Since orangefs is full of global state anyway (as the error
message in DUMP_DEVICE_ERROR explains, there can only be one userspace
orangefs filesystem driver at once), that shouldn't be a problem.

[
Why does orangefs even exist in the kernel if everything does upcalls into
userspace? What does orangefs do that couldn't be done with the FUSE
interface? If there is no good answer to those questions, I'd prefer to see
orangefs kicked out of the kernel. Can that be done for something that
shipped in a release?

According to commit f7ab093f74 ("Orangefs: kernel client part 1"), they
even already have a FUSE daemon, and the only rational reason (apart from
"but most of our users report preferring to use our kernel module instead")
given for not wanting to use FUSE is one "in-the-works" feature that could
probably be integated into FUSE instead.
]

This patch has been compile-tested.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-07-05 15:47:43 -04:00
Mike Marshall
3903f15008 Orangefs: allow O_DIRECT in open
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-07-05 15:47:35 -04:00
Andreas Gruenbacher
d373a712c1 orangefs: Remove useless xattr prefix arguments
Mike,

On Fri, Jun 3, 2016 at 9:44 PM, Mike Marshall <hubcap@omnibond.com> wrote:
> We use the return value in this one line you changed, our userspace code gets
> ill when we send it (-ENOMEM +1) as a key length...

ah, my mistake.  Here's a fixed version.

Thanks,
Andreas

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-07-05 15:47:27 -04:00
Andreas Gruenbacher
2ce8272a10 orangefs: Remove redundant "trusted." xattr handler
Orangefs has a catch-all xattr handler that effectively does what the
trusted handler does already.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-07-05 15:47:22 -04:00
Andreas Gruenbacher
972a7344fc orangefs: Remove useless defines
The ORANGEFS_XATTR_INDEX_ defines are unused; the ORANGEFS_XATTR_NAME_
defines only obfuscate the code.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-07-05 15:47:16 -04:00
Vegard Nossum
6a7fd522a7 ext4: don't call ext4_should_journal_data() on the journal inode
If ext4_fill_super() fails early, it's possible for ext4_evict_inode()
to call ext4_should_journal_data() before superblock options and flags
are fully set up.  In that case, the iput() on the journal inode can
end up causing a BUG().

Work around this problem by reordering the tests so we only call
ext4_should_journal_data() after we know it's not the journal inode.

Fixes: 2d859db3e4 ("ext4: fix data corruption in inodes with journalled data")
Fixes: 2b405bfa84 ("ext4: fix data=journal fast mount/umount hang")
Cc: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2016-07-04 11:03:00 -04:00
Vivek Goyal
07a2daab49 ovl: Copy up underlying inode's ->i_mode to overlay inode
Right now when a new overlay inode is created, we initialize overlay
inode's ->i_mode from underlying inode ->i_mode but we retain only
file type bits (S_IFMT) and discard permission bits.

This patch changes it and retains permission bits too. This should allow
overlay to do permission checks on overlay inode itself in task context.

[SzM] It also fixes clearing suid/sgid bits on write.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
2016-07-04 16:49:48 +02:00
Miklos Szeredi
b99c2d9138 ovl: handle ATTR_KILL*
Before 4bacc9c923 ("overlayfs: Make f_path...") file->f_path pointed to
the underlying file, hence suid/sgid removal on write worked fine.

After that patch file->f_path pointed to the overlay file, and the file
mode bits weren't copied to overlay_inode->i_mode.  So the suid/sgid
removal simply stopped working.

The fix is to copy the mode bits, but then ovl_setattr() needs to clear
ATTR_MODE to avoid the BUG() in notify_change().  So do this first, then in
the next patch copy the mode.

Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Cc: <stable@vger.kernel.org>
2016-07-04 16:49:48 +02:00
Pranay Kr. Srivastava
4743f83990 ext4: Fix WARN_ON_ONCE in ext4_commit_super()
If there are racing calls to ext4_commit_super() it's possible for
another writeback of the superblock to result in the buffer being
marked with an error after we check if the buffer is marked as having
a write error and the buffer up-to-date flag is set again.  If that
happens mark_buffer_dirty() can end up throwing a WARN_ON_ONCE.

Fix this by moving this check to write before we call
write_buffer_dirty(), and keeping the buffer locked during this whole
sequence.

Signed-off-by: Pranay Kr. Srivastava <pranjas@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-07-04 10:24:52 -04:00
Jan Kara
646caa9c8e ext4: fix deadlock during page writeback
Commit 06bd3c36a7 (ext4: fix data exposure after a crash) uncovered a
deadlock in ext4_writepages() which was previously much harder to hit.
After this commit xfstest generic/130 reproduces the deadlock on small
filesystems.

The problem happens when ext4_do_update_inode() sets LARGE_FILE feature
and marks current inode handle as synchronous. That subsequently results
in ext4_journal_stop() called from ext4_writepages() to block waiting for
transaction commit while still holding page locks, reference to io_end,
and some prepared bio in mpd structure each of which can possibly block
transaction commit from completing and thus results in deadlock.

Fix the problem by releasing page locks, io_end reference, and
submitting prepared bio before calling ext4_journal_stop().

[ Changed to defer the call to ext4_journal_stop() only if the handle
  is synchronous.  --tytso ]

Reported-and-tested-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
2016-07-04 10:14:01 -04:00
Al Viro
2864f30142 iget_locked et.al.: make sure we don't return bad inodes
If one thread does iget_locked(), proceeds to try and set
the new inode up and fails, inode will be unhashed and dropped.
However, another thread doing ilookup/iget_locked in the middle
of that would end up finding a half-set-up inode, grabbing
a reference, waiting for it to come unlocked and getting the
resulting bad inode.  It's a race (if that ilookup had been
called just after the failure of setup attempt it wouldn't
have found the sucker at all), particularly unpleasant in
cases when failure is transient/caller-dependent/etc.

While it can be dealt with in the callers, there's no reason
not to handle it in fs/inode.c primitives, especially since
the cost is trivial.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-03 23:15:21 -04:00
Daeho Jeong
fa96454069 ext4: correct error value of function verifying dx checksum
ext4_dx_csum_verify() returns the success return value in two checksum
verification failure cases. We need to set the return values to zero
as failure like ext4_dirent_csum_verify() returning zero when failing
to find a checksum dirent at the tail.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2016-07-03 21:11:08 -04:00
Daeho Jeong
b47820edd1 ext4: avoid modifying checksum fields directly during checksum verification
We temporally change checksum fields in buffers of some types of
metadata into '0' for verifying the checksum values. By doing this
without locking the buffer, some metadata's checksums, which are
being committed or written back to the storage, could be damaged.
In our test, several metadata blocks were found with damaged metadata
checksum value during recovery process. When we only verify the
checksum value, we have to avoid modifying checksum fields directly.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Youngjin Gil <youngjin.gil@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2016-07-03 17:51:39 -04:00
Linus Torvalds
0b295dd5b8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fix from Miklos Szeredi:
 "This makes sure userspace filesystems are not broken by the parallel
  lookups and readdir feature"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: serialize dirops by default
2016-07-03 12:02:00 -07:00
Linus Torvalds
236bfd8ed8 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "This contains fixes for a dentry leak, a regression in 4.6 noticed by
  Docker users and missing write access checking in truncate"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: warn instead of error if d_type is not supported
  ovl: get_write_access() in truncate
  ovl: fix dentry leak for default_permissions
2016-07-03 11:57:09 -07:00