If a directory's parent inode pointer doesn't point to an inode, the
directory should be flagged as corrupt. Enable IGET_UNTRUSTED here so
that _iget will return -EINVAL if the inobt does not confirm that the
inode is present and allocated and we can flag the directory corruption.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
There are a few places where we make a libxfs api call on behalf of some
object other than the one we're scrubbing but inadvertently call the
regular process_error function. When this happens we mark the object
corrupt even though it was corruption in /some other/ object that
actually produced the -EFSCORRUPTED code. The correct output flag for
these situations is SCRUB_OFLAG_XFAIL, not SCRUB_OFLAG_CORRUPT, so fix
this now that we also have a helper to set these.
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>
Fix smatch complaints about uninitialized return codes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Scrub parent pointers, sort of. For directories, we can ride the
'..' entry up to the parent to confirm that there's at most one
dentry that points back to this directory.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Darrick J. Wong