By splitting the b_fspriv field into two different fields (b_log_item
and b_li_list). It's possible to get rid of an old ABI workaround, by
using the new b_log_item field to store xfs_buf_log_item separated from
the log items attached to the buffer, which will be linked in the new
b_li_list field.
This way, there is no more need to reorder the log items list to place
the buf_log_item at the beginning of the list, simplifying a bit the
logic to handle buffer IO.
This also opens the possibility to change buffer's log items list into a
proper list_head.
b_log_item field is still defined as a void *, because it is still used
by the log buffers to store xlog_in_core structures, and there is no
need to add an extra field on xfs_buf just for xlog_in_core.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: minor style changes]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In xfs_scrub_dir_rec, we must walk through the directory block entries
to arrive at the offset given by the hash structure. If we blindly
trust the hash address, we can end up midway into a directory entry and
stray outside the block. Found by lastbit fuzzing lents[3].address in
xfs/390 with KASAN enabled.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
If a malicious filesystem image contains a block+ format directory
wherein the directory inode's core.mode is set such that
S_ISDIR(core.mode) == 0, and if there are subdirectories of the
corrupted directory, an attempt to traverse up the directory tree will
crash the kernel in __xfs_dir3_data_check. Running the online scrub's
parent checks will tend to do this.
The crash occurs because the directory inode's d_ops get set to
xfs_dir[23]_nondir_ops (it's not a directory) but the parent pointer
scrubber's indiscriminate call to xfs_readdir proceeds past the ASSERT
if we have non fatal asserts configured.
Fix the null pointer dereference crash in __xfs_dir3_data_check by
looking for S_ISDIR or wrong d_ops; and teach the parent scrubber
to bail out if it is fed a non-directory "parent".
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Expose all metadata structure buffer verifier functions via buf_ops.
These will be used by the online scrub mechanism to look for problems
with buffers that are already sitting around in memory.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Refactor the callers of verifiers to print the instruction address of a
failing check.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Modify each function that checks the contents of a metadata buffer to
return the instruction address of the failing test so that we can report
more precise failure errors to the log.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Since all verification errors also mark the buffer as having an error,
we can combine these two calls. Later we'll add a xfs_failaddr_t
parameter to promote the idea of reporting corruption errors and the
address of the failing check to enable better debugging reports.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Since __xfs_dir3_data_check verifies on-disk metadata, we can't have it
noisily blowing asserts and hanging the system on corrupt data coming in
off the disk. Instead, have it return a boolean like all the other
checker functions, and only have it noisily fail if we fail in debug
mode.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
When we're checking the entries in a directory buffer, make sure that
the entry length doesn't push us off the end of the buffer. Found via
xfs/388 writing ones to the length fields.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
In xfs_dir3_data_read, we can encounter the situation where err == 0 and
*bpp == NULL if the given bno offset happens to be a hole; this leads to
a crash if we try to set the buffer type after the _da_read_buf call.
Holes can happen due to corrupt or malicious entries in the bmbt data,
so be a little more careful when we're handling buffers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Refactor the implementations of xfs_dir2_data_freescan into a
routine that takes the raw directory block parameters and
a second function that figures out the raw parameters from the
directory inode. This enables us to use the exact same code
for both userspace and the kernel, since repair knows exactly
which directory block geometry parameters it needs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This adds a name to each buf_ops structure, so that if
a verifier fails we can print the type of verifier that
failed it. Should be a slight debugging aid, I hope.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Since the onset of v5 superblocks, the LSN of the last modification has
been included in a variety of on-disk data structures. This LSN is used
to provide log recovery ordering guarantees (e.g., to ensure an older
log recovery item is not replayed over a newer target data structure).
While this works correctly from the point a filesystem is formatted and
mounted, userspace tools have some problematic behaviors that defeat
this mechanism. For example, xfs_repair historically zeroes out the log
unconditionally (regardless of whether corruption is detected). If this
occurs, the LSN of the filesystem is reset and the log is now in a
problematic state with respect to on-disk metadata structures that might
have a larger LSN. Until either the log catches up to the highest
previously used metadata LSN or each affected data structure is modified
and written out without incident (which resets the metadata LSN), log
recovery is susceptible to filesystem corruption.
This problem is ultimately addressed and repaired in the associated
userspace tools. The kernel is still responsible to detect the problem
and notify the user that something is wrong. Check the superblock LSN at
mount time and fail the mount if it is invalid. From that point on,
trigger verifier failure on any metadata I/O where an invalid LSN is
detected. This results in a filesystem shutdown and guarantees that we
do not log metadata changes with invalid LSNs on disk. Since this is a
known issue with a known recovery path, present a warning to instruct
the user how to recover.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In the dir3 data block readahead function, use the regular read
verifier to check the block's CRC and spot-check the block contents
instead of directly calling only the spot-checking routine. This
prevents corrupted directory data blocks from being read into the
kernel, which can lead to garbage ls output and directory loops (if
say one of the entries contains slashes and other junk).
cc: <stable@vger.kernel.org> # 3.12 - 4.2
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This adds a new superblock field, sb_meta_uuid. If set, along with
a new incompat flag, the code will use that field on a V5 filesystem
to compare to metadata UUIDs, which allows us to change the user-
visible UUID at will. Userspace handles the setting and clearing
of the incompat flag as appropriate, as the UUID gets changed; i.e.
setting the user-visible UUID back to the original UUID (as stored in
the new field) will remove the incompatible feature flag.
If the incompat flag is not set, this copies the user-visible UUID into
into the meta_uuid slot in memory when the superblock is read from disk;
the meta_uuid field is not written back to disk in this case.
The remainder of this patch simply switches verifiers, initializers,
etc to use the new sb_meta_uuid field.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Today, if we hit an XFS_WANT_CORRUPTED_RETURN we don't print any
information about which filesystem hit it. Passing in the mp allows
us to print the filesystem (device) name, which is a pretty critical
piece of information.
Tested by running fsfuzzer 'til I hit some.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
More on-disk format consolidation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
More on-disk format consolidation. A few declarations that weren't on-disk
format related move into better suitable spots.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Convert all the errors the core XFs code to negative error signs
like the rest of the kernel and remove all the sign conversion we
do in the interface layers.
Errors for conversion (and comparison) found via searches like:
$ git grep " E" fs/xfs
$ git grep "return E" fs/xfs
$ git grep " E[A-Z].*;$" fs/xfs
Negation points found via searches like:
$ git grep "= -[a-z,A-Z]" fs/xfs
$ git grep "return -[a-z,A-D,F-Z]" fs/xfs
$ git grep " -[a-z].*;" fs/xfs
[ with some bits I missed from Brian Foster ]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Move all the source files that are shared with userspace into
libxfs/. This is done as one big chunk simpy to get it done
quickly
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Carlos Maiolino