Make the use of reserved blocks an explicit parameter to xfs_attr_set.
Userspace setting XFS_ATTR_ROOT attrs should continue to be able to use
it, but for online repairs we can back out and therefore do not care.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
In preparation for online/offline repair wanting to use xfs_attr_set,
move some of the boilerplate out of this function into the callers.
Repair can initialize the da_args completely, and the userspace flag
handling/twisting goes away once we move it to xfs_attr_change.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Pass the attr value to put_listent when we have local xattrs or
shortform xattrs. This will enable the GETPARENTS ioctl to use
xfs_attr_list as its backend.
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Parent pointers are internal filesystem metadata. They're not intended
to be directly visible to userspace, so filter them out of
xfs_xattr_put_listent so that they don't appear in listxattr.
Signed-off-by: Allison Henderson <allison.henderson@oracle.com>
Inspired-by: Andrey Albershteyn <aalbersh@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: change this to XFS_ATTR_PRIVATE_NSP_MASK per fsverity patchset]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Per reviewer request, use an OPSTATE flag (+ helpers) to decide if
logged xattrs are enabled, instead of querying the xfs_sb.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Parent pointers match attrs on name+value, unlike everything else which
matches on only the name. Therefore, we cannot keep using the heuristic
that !value means remove. Make this an explicit operation code.
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>
While reviewing the online fsck patchset, someone spied the
xfs_swapext_can_use_without_log_assistance function and wondered why we
go through this inverted-bitmask dance to avoid setting the
XFS_SB_FEAT_INCOMPAT_LOG_SWAPEXT feature.
(The same principles apply to the logged extended attribute update
feature bit in the since-merged LARP series.)
The reason for this dance is that xfs_add_incompat_log_feature is an
expensive operation -- it forces the log, pushes the AIL, and then if
nobody's beaten us to it, sets the feature bit and issues a synchronous
write of the primary superblock. That could be a one-time cost
amortized over the life of the filesystem, but the log quiesce and cover
operations call xfs_clear_incompat_log_features to remove feature bits
opportunistically. On a moderately loaded filesystem this leads to us
cycling those bits on and off over and over, which hurts performance.
Why do we clear the log incompat bits? Back in ~2020 I think Dave and I
had a conversation on IRC[2] about what the log incompat bits represent.
IIRC in that conversation we decided that the log incompat bits protect
unrecovered log items so that old kernels won't try to recover them and
barf. Since a clean log has no protected log items, we could clear the
bits at cover/quiesce time.
As Dave Chinner pointed out in the thread, clearing log incompat bits at
unmount time has positive effects for golden root disk image generator
setups, since the generator could be running a newer kernel than what
gets written to the golden image -- if there are log incompat fields set
in the golden image that was generated by a newer kernel/OS image
builder then the provisioning host cannot mount the filesystem even
though the log is clean and recovery is unnecessary to mount the
filesystem.
Given that it's expensive to set log incompat bits, we really only want
to do that once per bit per mount. Therefore, I propose that we only
clear log incompat bits as part of writing a clean unmount record. Do
this by adding an operational state flag to the xfs mount that guards
whether or not the feature bit clearing can actually take place.
This eliminates the l_incompat_users rwsem that we use to protect a log
cleaning operation from clearing a feature bit that a frontend thread is
trying to set -- this lock adds another way to fail w.r.t. locking. For
the swapext series, I shard that into multiple locks just to work around
the lockdep complaints, and that's fugly.
Link: https://lore.kernel.org/linux-xfs/20240131230043.GA6180@frogsfrogsfrogs/
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
In a few patches, we'll add some online repair code that tries to
massage the ondisk inode record just enough to get it to pass the inode
verifiers so that we can continue with more file repairs. Part of that
massaging can include zapping the ondisk forks to clear errors. After
that point, the bmap fork repair functions will rebuild the zapped
forks.
Christoph asked for stronger protections against online repair zapping a
fork to get the inode to load vs. other threads trying to access the
partially repaired file. Do this by adding a special "[DA]FORK_ZAPPED"
inode health flag whenever repair zaps a fork, and sprinkling checks for
that flag into the various file operations for things that don't like
handling an unexpected zero-extents fork.
In practice xfs_scrub will scrub and fix the forks almost immediately
after zapping them, so the window is very small. However, if a crash or
unmount should occur, we can still detect these zapped inode forks by
looking for a zero-extents fork when data was expected.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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Merge tag 'vfs-6.7.xattr' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs xattr updates from Christian Brauner:
"The 's_xattr' field of 'struct super_block' currently requires a
mutable table of 'struct xattr_handler' entries (although each handler
itself is const). However, no code in vfs actually modifies the
tables.
This changes the type of 's_xattr' to allow const tables, and modifies
existing file systems to move their tables to .rodata. This is
desirable because these tables contain entries with function pointers
in them; moving them to .rodata makes it considerably less likely to
be modified accidentally or maliciously at runtime"
* tag 'vfs-6.7.xattr' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
const_structs.checkpatch: add xattr_handler
net: move sockfs_xattr_handlers to .rodata
shmem: move shmem_xattr_handlers to .rodata
overlayfs: move xattr tables to .rodata
xfs: move xfs_xattr_handlers to .rodata
ubifs: move ubifs_xattr_handlers to .rodata
squashfs: move squashfs_xattr_handlers to .rodata
smb: move cifs_xattr_handlers to .rodata
reiserfs: move reiserfs_xattr_handlers to .rodata
orangefs: move orangefs_xattr_handlers to .rodata
ocfs2: move ocfs2_xattr_handlers and ocfs2_xattr_handler_map to .rodata
ntfs3: move ntfs_xattr_handlers to .rodata
nfs: move nfs4_xattr_handlers to .rodata
kernfs: move kernfs_xattr_handlers to .rodata
jfs: move jfs_xattr_handlers to .rodata
jffs2: move jffs2_xattr_handlers to .rodata
hfsplus: move hfsplus_xattr_handlers to .rodata
hfs: move hfs_xattr_handlers to .rodata
gfs2: move gfs2_xattr_handlers_max to .rodata
fuse: move fuse_xattr_handlers to .rodata
...
This makes it harder for accidental or malicious changes to
xfs_xattr_handlers at runtime.
Cc: "Darrick J. Wong" <djwong@kernel.org>
Cc: linux-xfs@vger.kernel.org
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20230930050033.41174-27-wedsonaf@gmail.com
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
While reviewing the FIEXCHANGE code in XFS, I realized that the function
that enables logged xattrs doesn't actually check that the superblock
has a LOG_INCOMPAT feature bit field. Add a check to refuse the
operation if we don't have a V5 filesystem...
...but on second though, let's require either reflink or rmap so that we
only have to deal with LARP mode on relatively /modern/ kernel. 4.14 is
about as far back as I feel like going.
Seeing as LARP is a debugging-only option anyway, this isn't likely to
affect any real users.
Fixes: d9c61ccb3b ("xfs: move xfs_attr_use_log_assist out of xfs_log.c")
Really-Fixes: f3f36c893f ("xfs: Add xfs_attr_set_deferred and xfs_attr_remove_deferred")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Bill O'Donnell <bodonnel@redhat.com>
Remove struct posix_acl_{access,default}_handler for all filesystems
that don't depend on the xattr handler in their inode->i_op->listxattr()
method in any way. There's nothing more to do than to simply remove the
handler. It's been effectively unused ever since we introduced the new
posix acl api.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
When -Wstringop-truncation is enabled, the compiler complains about
truncation of the null byte at the end of the xattr name prefix. This
is intentional, since we're concatenating the two strings together and
do _not_ want a null byte in the middle of the name.
We've already ensured that the name buffer is long enough to handle
prefix and name, and the prefix_len is supposed to be the length of the
prefix string without the null byte, so use memcpy here instead.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
I found a race involving the larp control knob, aka the debugging knob
that lets developers enable logging of extended attribute updates:
Thread 1 Thread 2
echo 0 > /sys/fs/xfs/debug/larp
setxattr(REPLACE)
xfs_has_larp (returns false)
xfs_attr_set
echo 1 > /sys/fs/xfs/debug/larp
xfs_attr_defer_replace
xfs_attr_init_replace_state
xfs_has_larp (returns true)
xfs_attr_init_remove_state
<oops, wrong DAS state!>
This isn't a particularly severe problem right now because xattr logging
is only enabled when CONFIG_XFS_DEBUG=y, and developers *should* know
what they're doing.
However, the eventual intent is that callers should be able to ask for
the assistance of the log in persisting xattr updates. This capability
might not be required for /all/ callers, which means that dynamic
control must work correctly. Once an xattr update has decided whether
or not to use logged xattrs, it needs to stay in that mode until the end
of the operation regardless of what subsequent parallel operations might
do.
Therefore, it is an error to continue sampling xfs_globals.larp once
xfs_attr_change has made a decision about larp, and it was not correct
for me to have told Allison that ->create_intent functions can sample
the global log incompat feature bitfield to decide to elide a log item.
Instead, create a new op flag for the xfs_da_args structure, and convert
all other callers of xfs_has_larp and xfs_sb_version_haslogxattrs within
the attr update state machine to look for the operations flag.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
The LARP patchset added an awkward coupling point between libxfs and
what would be libxlog, if the XFS log were actually its own library.
Move the code that sets up logged xattr updates out of libxfs and into
xfs_xattr.c so that libxfs no longer has to know about xlog_* functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The LARP patchset added an awkward coupling point between libxfs and
what would be libxlog, if the XFS log were actually its own library.
Move the code that enables logged xattr updates out of "lib"xlog and into
xfs_xattr.c so that it no longer has to know about xlog_* functions.
While we're at it, give xfs_xattr.c its own header file.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We current use XFS_DAS_UNINIT for several steps in the attr_set
state machine. We use it for setting shortform xattrs, converting
from shortform to leaf, leaf add, leaf-to-node and leaf add. All of
these things are essentially known before we start the state machine
iterating, so we really should separate them out:
XFS_DAS_SF_ADD:
- tries to do a shortform add
- on success -> done
- on ENOSPC converts to leaf, -> XFS_DAS_LEAF_ADD
- on error, dies.
XFS_DAS_LEAF_ADD:
- tries to do leaf add
- on success:
- inline attr -> done
- remote xattr || REPLACE -> XFS_DAS_FOUND_LBLK
- on ENOSPC converts to node, -> XFS_DAS_NODE_ADD
- on error, dies
XFS_DAS_NODE_ADD:
- tries to do node add
- on success:
- inline attr -> done
- remote xattr || REPLACE -> XFS_DAS_FOUND_NBLK
- on error, dies
This makes it easier to understand how the state machine starts
up and sets us up on the path to further state machine
simplifications.
This also converts the DAS state tracepoints to use strings rather
than numbers, as converting between enums and numbers requires
manual counting rather than just reading the name.
This also introduces a XFS_DAS_DONE state so that we can trace
successful operation completions easily.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Henderson<allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Files containing metadata (quota records, rt bitmap and summary info)
are fully managed by the filesystem, which means that all resource
cleanup must be explicit, not automatic. This means that they should
never be subjected automatic to post-eof truncation, nor should they be
freed automatically even if the link count drops to zero.
In other words, xfs_inactive() should leave these files alone. Add the
necessary predicate functions to make this happen. This adds a second
layer of prevention for the kinds of fs corruption that was fixed by
commit f4c32e87de. If we ever decide to support removing metadata
files, we should make all those metadata updates explicit.
Rearrange the order of #includes to fix compiler errors, since
xfs_mount.h is supposed to be included before xfs_inode.h
Followup-to: f4c32e87de ("xfs: fix realtime bitmap/summary file truncation when growing rt volume")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.
Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Remove duplicate headers which are included twice.
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The attrlist cursor only exists as part of an attr list context, so
embedd the structure instead of pointing to it. Also give it a proper
xfs_ prefix and remove the obsolete typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The ATTR_* flags have a long IRIX history, where they a userspace
interface, the on-disk format and an internal interface. We've split
out the on-disk interface to the XFS_ATTR_* values, but despite (or
because?) of that the flag have still been a mess. Switch the
internal interface to pass the on-disk XFS_ATTR_* flags for the
namespace and the Linux XATTR_* flags for the actual flags instead.
The ATTR_* values that are actually used are move to xfs_fs.h with a
new XFS_IOC_* prefix to not conflict with the userspace version that
has the same name and must have the same value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Move the function to xfs_acl.c and provide a proper stub for the
!CONFIG_XFS_POSIX_ACL case. Lift the flags check to the caller as it
nicely fits in there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The version taking the context structure is the main interface to list
attributes, so drop the _int postfix.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Replace the alist char pointer with a void buffer given that different
callers use it in different ways. Use the chance to remove the typedef
and reduce the indentation of the struct definition so that it doesn't
overflow 80 char lines all over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We can just pass down the Linux convention of a zero valuelen to just
query for the existance of an attribute to the low-level code instead.
The use in the legacy xfs_attr_list code only used by the ioctl
interface was already dead code, as the callers check that the flag
is not present.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Instead of converting from one style of arguments to another in
xfs_attr_set, pass the structure from higher up in the call chain.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Instead of converting from one style of arguments to another in
xfs_attr_set, pass the structure from higher up in the call chain.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The Linux xattr and acl APIs use a single call for set and remove.
Modify the high-level XFS API to match that and let xfs_attr_set handle
removing attributes as well. With a little bit of reordering this
removes a lot of code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This helps to pre-simplify the extra handling of the null terminator in
delayed operations which use memcpy rather than strlen. Later
when we introduce parent pointers, attribute names will become binary,
so strlen will not work at all. Removing uses of strlen now will
help reduce complexities later
Signed-off-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We should not just invalidate the ACL when setting the underlying
attribute, but also when removing it. The ioctl interface gets that
right, but the normal xattr inteface skipped the xfs_forget_acl due
to an early return.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Some of the xfs source files are missing header includes, so add them
back. Sparse complains about non-static functions that don't have a
forward declaration anywhere.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When doing file lookups and checking for permissions, we end up in
xfs_get_acl() to see if there are any ACLs on the inode. This
requires and xattr lookup, and to do that we have to supply a buffer
large enough to hold an maximum sized xattr.
On workloads were we are accessing a wide range of cache cold files
under memory pressure (e.g. NFS fileservers) we end up spending a
lot of time allocating the buffer. The buffer is 64k in length, so
is a contiguous multi-page allocation, and if that then fails we
fall back to vmalloc(). Hence the allocation here is /expensive/
when we are looking up hundreds of thousands of files a second.
Initial numbers from a bpf trace show average time in xfs_get_acl()
is ~32us, with ~19us of that in the memory allocation. Note these
are average times, so there are going to be affected by the worst
case allocations more than the common fast case...
To avoid this, we could just do a "null" lookup to see if the ACL
xattr exists and then only do the allocation if it exists. This,
however, optimises the path for the "no ACL present" case at the
expense of the "acl present" case. i.e. we can halve the time in
xfs_get_acl() for the no acl case (i.e down to ~10-15us), but that
then increases the ACL case by 30% (i.e. up to 40-45us).
To solve this and speed up both cases, drive the xattr buffer
allocation into the attribute code once we know what the actual
xattr length is. For the no-xattr case, we avoid the allocation
completely, speeding up that case. For the common ACL case, we'll
end up with a fast heap allocation (because it'll be smaller than a
page), and only for the rarer "we have a remote xattr" will we have
a multi-page allocation occur. Hence the common ACL case will be
much faster, too.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are many, many xfs header files which are included but
unneeded (or included twice) in the xfs code, so remove them.
nb: xfs_linux.h includes about 9 headers for everyone, so those
explicit includes get removed by this. I'm not sure what the
preference is, but if we wanted explicit includes everywhere,
a followup patch could remove those xfs_*.h includes from
xfs_linux.h and move them into the files that need them.
Or it could be left as-is.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The inode geometry structure isn't related to ondisk format; it's
support for the mount structure. Move it to xfs_shared.h.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
For VFS listxattr calls, xfs_xattr_put_listent calls
__xfs_xattr_put_listent twice if it sees an attribute
"trusted.SGI_ACL_FILE": once for that name, and again for
"system.posix_acl_access". Unfortunately, if we happen to run out of
buffer space while emitting the first name, we set count to -1 (so that
we can feed ERANGE to the caller). The second invocation doesn't check that
the context parameters make sense and overwrites the byte before the
buffer, triggering a KASAN report:
==================================================================
BUG: KASAN: slab-out-of-bounds in strncpy+0xb3/0xd0
Write of size 1 at addr ffff88807fbd317f by task syz/1113
CPU: 3 PID: 1113 Comm: syz Not tainted 5.0.0-rc6-xfsx #rc6
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
dump_stack+0xcc/0x180
print_address_description+0x6c/0x23c
kasan_report.cold.3+0x1c/0x35
strncpy+0xb3/0xd0
__xfs_xattr_put_listent+0x1a9/0x2c0 [xfs]
xfs_attr_list_int_ilocked+0x11af/0x1800 [xfs]
xfs_attr_list_int+0x20c/0x2e0 [xfs]
xfs_vn_listxattr+0x225/0x320 [xfs]
listxattr+0x11f/0x1b0
path_listxattr+0xbd/0x130
do_syscall_64+0x139/0x560
While we're at it we add an assert to the other put_listent to avoid
this sort of thing ever happening to the attrlist_by_handle code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/
This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:
for f in `git grep -l "GNU General" fs/xfs/` ; do
echo $f
cat $f | awk -f hdr.awk > $f.new
mv -f $f.new $f
done
And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:
$ cat hdr.awk
BEGIN {
hdr = 1.0
tag = "GPL-2.0"
str = ""
}
/^ \* This program is free software/ {
hdr = 2.0;
next
}
/any later version./ {
tag = "GPL-2.0+"
next
}
/^ \*\// {
if (hdr > 0.0) {
print "// SPDX-License-Identifier: " tag
print str
print $0
str=""
hdr = 0.0
next
}
print $0
next
}
/^ \* / {
if (hdr > 1.0)
next
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
next
}
/^ \*/ {
if (hdr > 0.0)
next
print $0
next
}
// {
if (hdr > 0.0) {
if (str != "")
str = str "\n"
str = str $0
next
}
print $0
}
END { }
$
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are a handful of xattr functions which now return
nothing but zero. They can be made void, chased through calling
functions, and error handling etc can be removed.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Commit 2a6fba6 "xfs: only return -errno or success from attr ->put_listent"
changes the returnvalue of __xfs_xattr_put_listen to 0 in case when there is
insufficient space in the buffer assuming that setting context->count to -1
would be enough, but all of the ->put_listent callers only check seen_enough.
This results in a failed assertion:
XFS: Assertion failed: context->count >= 0, file: fs/xfs/xfs_xattr.c, line: 175
in insufficient buffer size case.
This is only reproducible with at least 2 xattrs and only when the buffer
gets depleted before the last one.
Furthermore if buffersize is such that it is enough to hold the last xattr's
name, but not enough to hold the sum of preceeding xattr names listxattr won't
fail with ERANGE, but will suceed returning last xattr's name without the
first character. The first character end's up overwriting data stored at
(context->alist - 1).
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Pull vfs fixes from Al Viro:
"Followups to the parallel lookup work:
- update docs
- restore killability of the places that used to take ->i_mutex
killably now that we have down_write_killable() merged
- Additionally, it turns out that I missed a prerequisite for
security_d_instantiate() stuff - ->getxattr() wasn't the only thing
that could be called before dentry is attached to inode; with smack
we needed the same treatment applied to ->setxattr() as well"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch ->setxattr() to passing dentry and inode separately
switch xattr_handler->set() to passing dentry and inode separately
restore killability of old mutex_lock_killable(&inode->i_mutex) users
add down_write_killable_nested()
update D/f/directory-locking
Changes in this update:
o fixes for mount line parsing, sparse warnings, read-only compat
feature remount behaviour
o allow fast path symlink lookups for inline symlinks.
o attribute listing cleanups
o writeback goes direct to bios rather than indirecting through
bufferheads
o transaction allocation cleanup
o optimised kmem_realloc
o added configurable error handling for metadata write errors,
changed default error handling behaviour from "retry forever" to
"retry until unmount then fail"
o fixed several inode cluster writeback lookup vs reclaim race
conditions
o fixed inode cluster writeback checking wrong inode after lookup
o fixed bugs where struct xfs_inode freeing wasn't actually RCU safe
o cleaned up inode reclaim tagging
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Merge tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs updates from Dave Chinner:
"A pretty average collection of fixes, cleanups and improvements in
this request.
Summary:
- fixes for mount line parsing, sparse warnings, read-only compat
feature remount behaviour
- allow fast path symlink lookups for inline symlinks.
- attribute listing cleanups
- writeback goes direct to bios rather than indirecting through
bufferheads
- transaction allocation cleanup
- optimised kmem_realloc
- added configurable error handling for metadata write errors,
changed default error handling behaviour from "retry forever" to
"retry until unmount then fail"
- fixed several inode cluster writeback lookup vs reclaim race
conditions
- fixed inode cluster writeback checking wrong inode after lookup
- fixed bugs where struct xfs_inode freeing wasn't actually RCU safe
- cleaned up inode reclaim tagging"
* tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (39 commits)
xfs: fix warning in xfs_finish_page_writeback for non-debug builds
xfs: move reclaim tagging functions
xfs: simplify inode reclaim tagging interfaces
xfs: rename variables in xfs_iflush_cluster for clarity
xfs: xfs_iflush_cluster has range issues
xfs: mark reclaimed inodes invalid earlier
xfs: xfs_inode_free() isn't RCU safe
xfs: optimise xfs_iext_destroy
xfs: skip stale inodes in xfs_iflush_cluster
xfs: fix inode validity check in xfs_iflush_cluster
xfs: xfs_iflush_cluster fails to abort on error
xfs: remove xfs_fs_evict_inode()
xfs: add "fail at unmount" error handling configuration
xfs: add configuration handlers for specific errors
xfs: add configuration of error failure speed
xfs: introduce table-based init for error behaviors
xfs: add configurable error support to metadata buffers
xfs: introduce metadata IO error class
xfs: configurable error behavior via sysfs
xfs: buffer ->bi_end_io function requires irq-safe lock
...
The value is not used; only names and value lengths are
returned. Remove the argument.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Today, the put_listent formatters return either 1 or 0; if
they return 1, some callers treat this as an error and return
it up the stack, despite "1" not being a valid (negative)
error code.
The intent seems to be that if the input buffer is full,
we set seen_enough or set count = -1, and return 1;
but some callers check the return before checking the
seen_enough or count fields of the context.
Fix this by only returning non-zero for actual errors
encountered, and rely on the caller to first check the
return value, then check the values in the context to
decide what to do.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead of adding the synthesized POSIX ACL attribute names after listing all
non-synthesized attributes, generate them immediately when listing the
non-synthesized attributes.
In addition, merge xfs_xattr_put_listent and xfs_xattr_put_listent_sizes to
ensure that the list size is computed correctly; the split version was
overestimating the list size for non-root users.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: xfs@oss.sgi.com
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add an additional "name" field to struct xattr_handler. When the name
is set, the handler matches attributes with exactly that name. When the
prefix is set instead, the handler matches attributes with the given
prefix and with a non-empty suffix.
This patch should avoid bugs like the one fixed in commit c361016a in
the future.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Remove POSIX_ACL_XATTR_{ACCESS,DEFAULT} and GFS2_POSIX_ACL_{ACCESS,DEFAULT}
and replace them with the definitions in <include/uapi/linux/xattr.h>.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Darrick J. Wong