Check parent pointer xattrs as part of scrubbing xattrs.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If the filesystem has parent pointers enabled, walk the parent pointers
of subdirectories to determine the true backref count. In theory each
subdir should have a single parent reachable via dotdot, but in the case
of (corrupt) subdirs with multiple parents, we need to keep the link
counts high enough that the directory loop detector will be able to
correct the multiple parents problems.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If the trylock-based dirent check fails, retain those parent pointers
and check them at the end. This may involve dropping the locks on the
file being scanned, so yay.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If the trylock-based parent pointer check fails, retain those dirents
and check them at the end. This may involve dropping the locks on the
file being scanned, so yay.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If the fs has parent pointers, we need to check that each child dirent
points to a file that has a parent pointer pointing back at us.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
In my haste to fix what I thought was a performance problem in the attr
scrub code, I neglected to notice that the xfs_attr_get_ilocked also had
the effect of checking that attributes can actually be looked up through
the attr dabtree. Fix this.
Fixes: 44af6c7e59 ("xfs: don't load local xattr values during scrub")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This patch removes the old parent pointer attribute during the rename
operation, and re-adds the updated parent pointer.
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: adjust to new ondisk format]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This patch modifies xfs_symlink to add a parent pointer to the inode.
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: minor rebase fixups]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This patch modifies xfs_link to add a parent pointer to the inode.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: minor rebase fixes]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add parent pointer attribute during xfs_create, and subroutines to
initialize attributes. Note that the xfs_attr_intent object contains a
pointer to the caller's xfs_da_args object, so the latter must persist
until transaction commit.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: shorten names, adjust to new format, set init_xattrs for parent
pointers]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Although directory entry and parent pointer recordsets look very similar
(name -> ino), there's one major difference between them: a file can be
hardlinked from multiple parent directories with the same filename.
This is common in shared container environments where a base directory
tree might be hardlink-copied multiple times. IOWs the same 'ls'
program might be hardlinked to multiple /srv/*/bin/ls paths.
We don't want parent pointer operations to bog down on hash collisions
between the same dirent name, so create a special hash function that
mixes in the parent directory inode number.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a separate function to compute name hashvalues for extended
attributes. When we get to parent pointers we'll be altering the rules
so that metadump obfuscation doesn't turn heinous.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a standardized helper function to enforce one namespace bit per
extended attribute, and refactor all the open-coded hweight logic. This
function is not a static inline to avoid porting hassles in userspace.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
While reviewing flag checking in the attr scrub functions, we noticed
that the shortform attr scanner didn't catch entries that have the LOCAL
or INCOMPLETE bits set. Neither of these flags can ever be set on a
shortform attr, so we need to check this narrower set of valid flags.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The xattr scrubber doesn't check for undefined flags in shortform attr
entries. Therefore, define a mask XFS_ATTR_ONDISK_MASK that has all
possible XFS_ATTR_* flags in it, and use that to check for unknown bits
in xchk_xattr_actor.
Refactor the check in the dabtree scanner function to use the new mask
as well. The redundant checks need to be in place because the dabtree
check examines the hash mappings and therefore needs to decode the attr
leaf entries to compute the namehash. This happens before the walk of
the xattr entries themselves.
Fixes: ae0506eba7 ("xfs: check used space of shortform xattr structures")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This field only ever contains XATTR_{CREATE,REPLACE}, and it only goes
as deep as xfs_attr_set. Remove the field from the structure and
replace it with an enum specifying exactly what kind of change we want
to make to the xattr structure. Upsert is the name that we'll give to
the flags==0 operation, because we're either updating an existing value
or inserting it, and the caller doesn't care.
Note: The "UPSERTR" name created here is to make userspace porting
easier. It will be removed in the next patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The only user of this flag sets it prior to an xfs_attr_get_ilocked
call, which doesn't update anything. Get rid of the flag.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
To prepare for re-enabling delalloc on RT devices, track the data blocks
(which use the RT device when the inode sits on it) and the indirect
blocks (which don't) separately to xfs_mod_delalloc, and add a new
percpu counter to also track the RT delalloc blocks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
xfs_mod_freecounter has two entirely separate code paths for adding or
subtracting from the free counters. Only the subtract case looks at the
rsvd flag and can return an error.
Split xfs_mod_freecounter into separate helpers for subtracting or
adding the freecounter, and remove all the impossible to reach error
handling for the addition case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Create helper functions to deal with locking realtime metadata inodes.
This enables us to maintain correct locking order once we start adding
the realtime rmap and refcount btree inodes.
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
The function are defined in the rmap_repair.c file, but not called
elsewhere, so delete the unused function.
fs/xfs/scrub/rmap_repair.c:436:1: warning: unused function 'is_rt_data_fork'.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=8425
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
The "mp" pointer is the same as "sc->mp" so this change doesn't affect
runtime at all. However, it's nicer to use same name for both the lock
and the unlock.
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Sparse throws warnings about the interval tree functions that are
defined and then not used in the scrub bitmap code:
fs/xfs/scrub/bitmap.c:57:1: warning: unused function 'xbitmap64_tree_iter_next' [-Wunused-function]
INTERVAL_TREE_DEFINE(struct xbitmap64_node, bn_rbnode, uint64_t,
^
./include/linux/interval_tree_generic.h:151:33: note: expanded from macro 'INTERVAL_TREE_DEFINE'
ITSTATIC ITSTRUCT * \
^
<scratch space>:3:1: note: expanded from here
xbitmap64_tree_iter_next
^
fs/xfs/scrub/bitmap.c:331:1: warning: unused function 'xbitmap32_tree_iter_next' [-Wunused-function]
INTERVAL_TREE_DEFINE(struct xbitmap32_node, bn_rbnode, uint32_t,
^
./include/linux/interval_tree_generic.h:151:33: note: expanded from macro 'INTERVAL_TREE_DEFINE'
ITSTATIC ITSTRUCT * \
^
<scratch space>:59:1: note: expanded from here
xbitmap32_tree_iter_next
Fix these by marking the functions created by the interval tree
creation macro as __maybe_unused to suppress this warning.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Scrub checks the superblock version number against the known good
feature bits that can be set in the version mask. It calculates
the version mask to compare like so:
vernum_mask = cpu_to_be16(~XFS_SB_VERSION_OKBITS |
XFS_SB_VERSION_NUMBITS |
XFS_SB_VERSION_ALIGNBIT |
XFS_SB_VERSION_DALIGNBIT |
XFS_SB_VERSION_SHAREDBIT |
XFS_SB_VERSION_LOGV2BIT |
XFS_SB_VERSION_SECTORBIT |
XFS_SB_VERSION_EXTFLGBIT |
XFS_SB_VERSION_DIRV2BIT);
This generates a sparse warning:
fs/xfs/scrub/agheader.c:168:23: warning: cast truncates bits from constant value (ffff3f8f becomes 3f8f)
This is because '~XFS_SB_VERSION_OKBITS' is considered a 32 bit
constant, even though it's value is always under 16 bits.
This is a kinda silly thing to do, because:
/*
* Supported feature bit list is just all bits in the versionnum field because
* we've used them all up and understand them all. Except, of course, for the
* shared superblock bit, which nobody knows what it does and so is unsupported.
*/
#define XFS_SB_VERSION_OKBITS \
((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
~XFS_SB_VERSION_SHAREDBIT)
#define XFS_SB_VERSION_NUMBITS 0x000f
#define XFS_SB_VERSION_ALLFBITS 0xfff0
#define XFS_SB_VERSION_SHAREDBIT 0x0200
XFS_SB_VERSION_OKBITS has a value of 0xfdff, and so
~XFS_SB_VERSION_OKBITS == XFS_SB_VERSION_SHAREDBIT. The calculated
mask already sets XFS_SB_VERSION_SHAREDBIT, so starting with
~XFS_SB_VERSION_OKBITS is completely redundant....
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
After creation, drop the ILOCK on temporary files that have been created
to stage a repair.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we've fixed the directory operations to hold the ILOCK until
they're finished with rmapbt updates for directory shape changes, we no
longer need to take this lock when scanning directories for rmapbt
records.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When a file-based metadata structure is being scrubbed in
xchk_metadata_inode_subtype, we should create an entirely new scrub
context so that each scrubber doesn't trip over another's buffers.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The VFS inc_nlink function does not explicitly check for integer
overflows in the i_nlink field. Instead, it checks the link count
against s_max_links in the vfs_{link,create,rename} functions. XFS
sets the maximum link count to 2.1 billion, so integer overflows should
not be a problem.
However. It's possible that online repair could find that a file has
more than four billion links, particularly if the link count got
corrupted while creating hardlinks to the file. The di_nlinkv2 field is
not large enough to store a value larger than 2^32, so we ought to
define a magic pin value of ~0U which means that the inode never gets
deleted. This will prevent a UAF error if the repair finds this
situation and users begin deleting links to the file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
v2/v3 inodes use di_nlink and not di_onlink; and v1 inodes use di_onlink
and not di_nlink. Whichever field is not in use, make sure its contents
are zero, and teach xfs_scrub to fix that if it is.
This clears a bunch of missing scrub failure errors in xfs/385 for
core.onlink.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Teach the AGI repair code to rebuild the unlinked buckets and lists.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Save ~460 bytes of stack space by moving all the repair context to a
heap object. We're going to add even more context data in the next
patch, which is why we really need to do this now.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If a symbolic link target looks bad, try to sift through the rubble to
find as much of the target buffer that we can, and stage a new target
(short or remote format as needed) in a temporary file and use the
atomic extent swapping mechanism to commit the results. In the worst
case, we replace the target with an overly long filename that cannot
possibly resolve.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When the orphanage adopts a file, that file becomes a child of the
orphanage. The dentry cache may have entries for the orphanage
directory and the name we've chosen, so (1) make sure we abort if the
dcache has a positive entry because something's not right; and (2)
invalidate and purge negative dentries if the adoption goes through.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If we encounter an inode with a nonzero link count but zero observed
links, move it to the orphanage.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we're repairing a directory structure or fixing the dotdot entry of
a subdirectory, it's possible that we won't ever find a parent for the
subdirectory. When this is the case, move it to the orphanage, aka
/lost+found.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
It's possible that the dentry cache can tell us the parent of a
directory. Therefore, when repairing directory dot dot entries, query
the dcache as a last resort before scanning the entire filesystem.
A reviewer asks:
"How high is the chance that we actually have a valid dcache entry for a
file in a corrupted directory?"
There's a decent chance of this actually working. Say you have a
1000-block directory foo, and block 980 gets corrupted. Let's further
suppose that block 0 has a correct entry for ".." and "bar". If someone
accesses /mnt/foo/bar, that will cause the dcache to create a dentry
from /mnt to /mnt/foo whose d_parent points back to /mnt. If you then
want to rebuild the directory, XFS can obtain the parent from the dcache
without needing to wander into parent pointers or scan the filesystem to
find /mnt's connection to foo.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Teach the online repair code to fix parent pointers for directories.
For now, this means correcting the dotdot entry of an existing directory
that is otherwise consistent.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Teach the online directory repair code to scan the filesystem so that we
can set the dotdot entry when we're rebuilding a directory. This
involves dropping ILOCK on the directory that we're repairing, which
means that the VFS can sneak in and tell us to update dotdot at any
time. Deal with these races by using a dirent hook to absorb dotdot
updates, and be careful not to check the scan results until after we've
retaken the ILOCK.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If a directory looks like it's in bad shape, try to sift through the
rubble to find whatever directory entries we can, scan the directory
tree for the parent (if needed), stage the new directory contents in a
temporary file and use the atomic extent swapping mechanism to commit
the results in bulk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we're repairing the link counts of a file, we must ensure either
that the file has zero link count and is on the unlinked list; or that
it has nonzero link count and is not on the unlinked list.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we have the means to tell if an inode is on an unlinked inode
list or not, we can check that an inode with zero link count is on the
unlinked list; and an inode that has nonzero link count is not on that
list. Make repair clean things up too.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a streamlined function to walk a file's xattrs, without all the
cursor management stuff in the regular listxattr.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Empty xattr leaf blocks at offset zero are a waste of space but
otherwise harmless. If we encounter one, flag it as an opportunity for
optimization.
If we encounter empty attr leaf blocks anywhere else in the attr fork,
that's corruption.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If an attr block indicates that it could use compaction, set the preen
flag to have the attr fork rebuilt, since the attr fork rebuilder can
take care of that for us.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If the extended attributes look bad, try to sift through the rubble to
find whatever keys/values we can, stage a new attribute structure in a
temporary file and use the atomic extent swapping mechanism to commit
the results in bulk.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Build on the code that was recently added to the temporary repair file
code so that we can atomically switch the contents of any file fork,
even if the fork is in local format. The upcoming functions to repair
xattrs, directories, and symlinks will need that capability.
Repair can lock out access to these user files by holding IOLOCK_EXCL on
these user files. Therefore, it is safe to drop the ILOCK of both the
file being repaired and the tempfile being used for staging, and cancel
the scrub transaction. We do this so that we can reuse the resource
estimation and transaction allocation functions used by a regular file
exchange operation.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a simple 'blob array' data structure for storage of arbitrarily
sized metadata objects that will be used to reconstruct metadata. For
the intended usage (temporarily storing extended attribute names and
values) we only have to support storing objects and retrieving them.
Use the xfile abstraction to store the attribute information in memory
that can be swapped out.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Create a new xfile function to discard the page cache that's backing
part of an xfile. The next patch wil use this to drop parts of an xfile
that aren't needed anymore.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
