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-rw-r--r--fs/xfs/scrub/dir.c876
1 files changed, 876 insertions, 0 deletions
diff --git a/fs/xfs/scrub/dir.c b/fs/xfs/scrub/dir.c
new file mode 100644
index 000000000..5c87800ab
--- /dev/null
+++ b/fs/xfs/scrub/dir.c
@@ -0,0 +1,876 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2017 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_log_format.h"
+#include "xfs_trans.h"
+#include "xfs_inode.h"
+#include "xfs_icache.h"
+#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/dabtree.h"
+
+/* Set us up to scrub directories. */
+int
+xchk_setup_directory(
+ struct xfs_scrub *sc)
+{
+ return xchk_setup_inode_contents(sc, 0);
+}
+
+/* Directories */
+
+/* Scrub a directory entry. */
+
+struct xchk_dir_ctx {
+ /* VFS fill-directory iterator */
+ struct dir_context dir_iter;
+
+ struct xfs_scrub *sc;
+};
+
+/* Check that an inode's mode matches a given DT_ type. */
+STATIC int
+xchk_dir_check_ftype(
+ struct xchk_dir_ctx *sdc,
+ xfs_fileoff_t offset,
+ xfs_ino_t inum,
+ int dtype)
+{
+ struct xfs_mount *mp = sdc->sc->mp;
+ struct xfs_inode *ip;
+ int ino_dtype;
+ int error = 0;
+
+ if (!xfs_has_ftype(mp)) {
+ if (dtype != DT_UNKNOWN && dtype != DT_DIR)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK,
+ offset);
+ goto out;
+ }
+
+ /*
+ * Grab the inode pointed to by the dirent. We release the
+ * inode before we cancel the scrub transaction. Since we're
+ * don't know a priori that releasing the inode won't trigger
+ * eofblocks cleanup (which allocates what would be a nested
+ * transaction), we can't use DONTCACHE here because DONTCACHE
+ * inodes can trigger immediate inactive cleanup of the inode.
+ *
+ * If _iget returns -EINVAL or -ENOENT then the child inode number is
+ * garbage and the directory is corrupt. If the _iget returns
+ * -EFSCORRUPTED or -EFSBADCRC then the child is corrupt which is a
+ * cross referencing error. Any other error is an operational error.
+ */
+ error = xfs_iget(mp, sdc->sc->tp, inum, 0, 0, &ip);
+ if (error == -EINVAL || error == -ENOENT) {
+ error = -EFSCORRUPTED;
+ xchk_fblock_process_error(sdc->sc, XFS_DATA_FORK, 0, &error);
+ goto out;
+ }
+ if (!xchk_fblock_xref_process_error(sdc->sc, XFS_DATA_FORK, offset,
+ &error))
+ goto out;
+
+ /* Convert mode to the DT_* values that dir_emit uses. */
+ ino_dtype = xfs_dir3_get_dtype(mp,
+ xfs_mode_to_ftype(VFS_I(ip)->i_mode));
+ if (ino_dtype != dtype)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
+ xfs_irele(ip);
+out:
+ return error;
+}
+
+/*
+ * Scrub a single directory entry.
+ *
+ * We use the VFS directory iterator (i.e. readdir) to call this
+ * function for every directory entry in a directory. Once we're here,
+ * we check the inode number to make sure it's sane, then we check that
+ * we can look up this filename. Finally, we check the ftype.
+ */
+STATIC bool
+xchk_dir_actor(
+ struct dir_context *dir_iter,
+ const char *name,
+ int namelen,
+ loff_t pos,
+ u64 ino,
+ unsigned type)
+{
+ struct xfs_mount *mp;
+ struct xfs_inode *ip;
+ struct xchk_dir_ctx *sdc;
+ struct xfs_name xname;
+ xfs_ino_t lookup_ino;
+ xfs_dablk_t offset;
+ bool checked_ftype = false;
+ int error = 0;
+
+ sdc = container_of(dir_iter, struct xchk_dir_ctx, dir_iter);
+ ip = sdc->sc->ip;
+ mp = ip->i_mount;
+ offset = xfs_dir2_db_to_da(mp->m_dir_geo,
+ xfs_dir2_dataptr_to_db(mp->m_dir_geo, pos));
+
+ if (xchk_should_terminate(sdc->sc, &error))
+ return !error;
+
+ /* Does this inode number make sense? */
+ if (!xfs_verify_dir_ino(mp, ino)) {
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
+ goto out;
+ }
+
+ /* Does this name make sense? */
+ if (!xfs_dir2_namecheck(name, namelen)) {
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
+ goto out;
+ }
+
+ if (!strncmp(".", name, namelen)) {
+ /* If this is "." then check that the inum matches the dir. */
+ if (xfs_has_ftype(mp) && type != DT_DIR)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK,
+ offset);
+ checked_ftype = true;
+ if (ino != ip->i_ino)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK,
+ offset);
+ } else if (!strncmp("..", name, namelen)) {
+ /*
+ * If this is ".." in the root inode, check that the inum
+ * matches this dir.
+ */
+ if (xfs_has_ftype(mp) && type != DT_DIR)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK,
+ offset);
+ checked_ftype = true;
+ if (ip->i_ino == mp->m_sb.sb_rootino && ino != ip->i_ino)
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK,
+ offset);
+ }
+
+ /* Verify that we can look up this name by hash. */
+ xname.name = name;
+ xname.len = namelen;
+ xname.type = XFS_DIR3_FT_UNKNOWN;
+
+ error = xfs_dir_lookup(sdc->sc->tp, ip, &xname, &lookup_ino, NULL);
+ /* ENOENT means the hash lookup failed and the dir is corrupt */
+ if (error == -ENOENT)
+ error = -EFSCORRUPTED;
+ if (!xchk_fblock_process_error(sdc->sc, XFS_DATA_FORK, offset,
+ &error))
+ goto out;
+ if (lookup_ino != ino) {
+ xchk_fblock_set_corrupt(sdc->sc, XFS_DATA_FORK, offset);
+ goto out;
+ }
+
+ /* Verify the file type. This function absorbs error codes. */
+ if (!checked_ftype) {
+ error = xchk_dir_check_ftype(sdc, offset, lookup_ino, type);
+ if (error)
+ goto out;
+ }
+out:
+ /*
+ * A negative error code returned here is supposed to cause the
+ * dir_emit caller (xfs_readdir) to abort the directory iteration
+ * and return zero to xchk_directory.
+ */
+ if (error == 0 && sdc->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ return false;
+ return !error;
+}
+
+/* Scrub a directory btree record. */
+STATIC int
+xchk_dir_rec(
+ struct xchk_da_btree *ds,
+ int level)
+{
+ struct xfs_da_state_blk *blk = &ds->state->path.blk[level];
+ struct xfs_mount *mp = ds->state->mp;
+ struct xfs_inode *dp = ds->dargs.dp;
+ struct xfs_da_geometry *geo = mp->m_dir_geo;
+ struct xfs_dir2_data_entry *dent;
+ struct xfs_buf *bp;
+ struct xfs_dir2_leaf_entry *ent;
+ unsigned int end;
+ unsigned int iter_off;
+ xfs_ino_t ino;
+ xfs_dablk_t rec_bno;
+ xfs_dir2_db_t db;
+ xfs_dir2_data_aoff_t off;
+ xfs_dir2_dataptr_t ptr;
+ xfs_dahash_t calc_hash;
+ xfs_dahash_t hash;
+ struct xfs_dir3_icleaf_hdr hdr;
+ unsigned int tag;
+ int error;
+
+ ASSERT(blk->magic == XFS_DIR2_LEAF1_MAGIC ||
+ blk->magic == XFS_DIR2_LEAFN_MAGIC);
+
+ xfs_dir2_leaf_hdr_from_disk(mp, &hdr, blk->bp->b_addr);
+ ent = hdr.ents + blk->index;
+
+ /* Check the hash of the entry. */
+ error = xchk_da_btree_hash(ds, level, &ent->hashval);
+ if (error)
+ goto out;
+
+ /* Valid hash pointer? */
+ ptr = be32_to_cpu(ent->address);
+ if (ptr == 0)
+ return 0;
+
+ /* Find the directory entry's location. */
+ db = xfs_dir2_dataptr_to_db(geo, ptr);
+ off = xfs_dir2_dataptr_to_off(geo, ptr);
+ rec_bno = xfs_dir2_db_to_da(geo, db);
+
+ if (rec_bno >= geo->leafblk) {
+ xchk_da_set_corrupt(ds, level);
+ goto out;
+ }
+ error = xfs_dir3_data_read(ds->dargs.trans, dp, rec_bno,
+ XFS_DABUF_MAP_HOLE_OK, &bp);
+ if (!xchk_fblock_process_error(ds->sc, XFS_DATA_FORK, rec_bno,
+ &error))
+ goto out;
+ if (!bp) {
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+ goto out;
+ }
+ xchk_buffer_recheck(ds->sc, bp);
+
+ if (ds->sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out_relse;
+
+ dent = bp->b_addr + off;
+
+ /* Make sure we got a real directory entry. */
+ iter_off = geo->data_entry_offset;
+ end = xfs_dir3_data_end_offset(geo, bp->b_addr);
+ if (!end) {
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+ goto out_relse;
+ }
+ for (;;) {
+ struct xfs_dir2_data_entry *dep = bp->b_addr + iter_off;
+ struct xfs_dir2_data_unused *dup = bp->b_addr + iter_off;
+
+ if (iter_off >= end) {
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+ goto out_relse;
+ }
+
+ if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
+ iter_off += be16_to_cpu(dup->length);
+ continue;
+ }
+ if (dep == dent)
+ break;
+ iter_off += xfs_dir2_data_entsize(mp, dep->namelen);
+ }
+
+ /* Retrieve the entry, sanity check it, and compare hashes. */
+ ino = be64_to_cpu(dent->inumber);
+ hash = be32_to_cpu(ent->hashval);
+ tag = be16_to_cpup(xfs_dir2_data_entry_tag_p(mp, dent));
+ if (!xfs_verify_dir_ino(mp, ino) || tag != off)
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+ if (dent->namelen == 0) {
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+ goto out_relse;
+ }
+ calc_hash = xfs_da_hashname(dent->name, dent->namelen);
+ if (calc_hash != hash)
+ xchk_fblock_set_corrupt(ds->sc, XFS_DATA_FORK, rec_bno);
+
+out_relse:
+ xfs_trans_brelse(ds->dargs.trans, bp);
+out:
+ return error;
+}
+
+/*
+ * Is this unused entry either in the bestfree or smaller than all of
+ * them? We've already checked that the bestfrees are sorted longest to
+ * shortest, and that there aren't any bogus entries.
+ */
+STATIC void
+xchk_directory_check_free_entry(
+ struct xfs_scrub *sc,
+ xfs_dablk_t lblk,
+ struct xfs_dir2_data_free *bf,
+ struct xfs_dir2_data_unused *dup)
+{
+ struct xfs_dir2_data_free *dfp;
+ unsigned int dup_length;
+
+ dup_length = be16_to_cpu(dup->length);
+
+ /* Unused entry is shorter than any of the bestfrees */
+ if (dup_length < be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length))
+ return;
+
+ for (dfp = &bf[XFS_DIR2_DATA_FD_COUNT - 1]; dfp >= bf; dfp--)
+ if (dup_length == be16_to_cpu(dfp->length))
+ return;
+
+ /* Unused entry should be in the bestfrees but wasn't found. */
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+}
+
+/* Check free space info in a directory data block. */
+STATIC int
+xchk_directory_data_bestfree(
+ struct xfs_scrub *sc,
+ xfs_dablk_t lblk,
+ bool is_block)
+{
+ struct xfs_dir2_data_unused *dup;
+ struct xfs_dir2_data_free *dfp;
+ struct xfs_buf *bp;
+ struct xfs_dir2_data_free *bf;
+ struct xfs_mount *mp = sc->mp;
+ u16 tag;
+ unsigned int nr_bestfrees = 0;
+ unsigned int nr_frees = 0;
+ unsigned int smallest_bestfree;
+ int newlen;
+ unsigned int offset;
+ unsigned int end;
+ int error;
+
+ if (is_block) {
+ /* dir block format */
+ if (lblk != XFS_B_TO_FSBT(mp, XFS_DIR2_DATA_OFFSET))
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ error = xfs_dir3_block_read(sc->tp, sc->ip, &bp);
+ } else {
+ /* dir data format */
+ error = xfs_dir3_data_read(sc->tp, sc->ip, lblk, 0, &bp);
+ }
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
+ goto out;
+ xchk_buffer_recheck(sc, bp);
+
+ /* XXX: Check xfs_dir3_data_hdr.pad is zero once we start setting it. */
+
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out_buf;
+
+ /* Do the bestfrees correspond to actual free space? */
+ bf = xfs_dir2_data_bestfree_p(mp, bp->b_addr);
+ smallest_bestfree = UINT_MAX;
+ for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
+ offset = be16_to_cpu(dfp->offset);
+ if (offset == 0)
+ continue;
+ if (offset >= mp->m_dir_geo->blksize) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out_buf;
+ }
+ dup = bp->b_addr + offset;
+ tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup));
+
+ /* bestfree doesn't match the entry it points at? */
+ if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG) ||
+ be16_to_cpu(dup->length) != be16_to_cpu(dfp->length) ||
+ tag != offset) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out_buf;
+ }
+
+ /* bestfree records should be ordered largest to smallest */
+ if (smallest_bestfree < be16_to_cpu(dfp->length)) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out_buf;
+ }
+
+ smallest_bestfree = be16_to_cpu(dfp->length);
+ nr_bestfrees++;
+ }
+
+ /* Make sure the bestfrees are actually the best free spaces. */
+ offset = mp->m_dir_geo->data_entry_offset;
+ end = xfs_dir3_data_end_offset(mp->m_dir_geo, bp->b_addr);
+
+ /* Iterate the entries, stopping when we hit or go past the end. */
+ while (offset < end) {
+ dup = bp->b_addr + offset;
+
+ /* Skip real entries */
+ if (dup->freetag != cpu_to_be16(XFS_DIR2_DATA_FREE_TAG)) {
+ struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
+
+ newlen = xfs_dir2_data_entsize(mp, dep->namelen);
+ if (newlen <= 0) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK,
+ lblk);
+ goto out_buf;
+ }
+ offset += newlen;
+ continue;
+ }
+
+ /* Spot check this free entry */
+ tag = be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup));
+ if (tag != offset) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out_buf;
+ }
+
+ /*
+ * Either this entry is a bestfree or it's smaller than
+ * any of the bestfrees.
+ */
+ xchk_directory_check_free_entry(sc, lblk, bf, dup);
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out_buf;
+
+ /* Move on. */
+ newlen = be16_to_cpu(dup->length);
+ if (newlen <= 0) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out_buf;
+ }
+ offset += newlen;
+ if (offset <= end)
+ nr_frees++;
+ }
+
+ /* We're required to fill all the space. */
+ if (offset != end)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+
+ /* Did we see at least as many free slots as there are bestfrees? */
+ if (nr_frees < nr_bestfrees)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+out_buf:
+ xfs_trans_brelse(sc->tp, bp);
+out:
+ return error;
+}
+
+/*
+ * Does the free space length in the free space index block ($len) match
+ * the longest length in the directory data block's bestfree array?
+ * Assume that we've already checked that the data block's bestfree
+ * array is in order.
+ */
+STATIC void
+xchk_directory_check_freesp(
+ struct xfs_scrub *sc,
+ xfs_dablk_t lblk,
+ struct xfs_buf *dbp,
+ unsigned int len)
+{
+ struct xfs_dir2_data_free *dfp;
+
+ dfp = xfs_dir2_data_bestfree_p(sc->mp, dbp->b_addr);
+
+ if (len != be16_to_cpu(dfp->length))
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+
+ if (len > 0 && be16_to_cpu(dfp->offset) == 0)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+}
+
+/* Check free space info in a directory leaf1 block. */
+STATIC int
+xchk_directory_leaf1_bestfree(
+ struct xfs_scrub *sc,
+ struct xfs_da_args *args,
+ xfs_dir2_db_t last_data_db,
+ xfs_dablk_t lblk)
+{
+ struct xfs_dir3_icleaf_hdr leafhdr;
+ struct xfs_dir2_leaf_tail *ltp;
+ struct xfs_dir2_leaf *leaf;
+ struct xfs_buf *dbp;
+ struct xfs_buf *bp;
+ struct xfs_da_geometry *geo = sc->mp->m_dir_geo;
+ __be16 *bestp;
+ __u16 best;
+ __u32 hash;
+ __u32 lasthash = 0;
+ __u32 bestcount;
+ unsigned int stale = 0;
+ int i;
+ int error;
+
+ /* Read the free space block. */
+ error = xfs_dir3_leaf_read(sc->tp, sc->ip, lblk, &bp);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
+ return error;
+ xchk_buffer_recheck(sc, bp);
+
+ leaf = bp->b_addr;
+ xfs_dir2_leaf_hdr_from_disk(sc->ip->i_mount, &leafhdr, leaf);
+ ltp = xfs_dir2_leaf_tail_p(geo, leaf);
+ bestcount = be32_to_cpu(ltp->bestcount);
+ bestp = xfs_dir2_leaf_bests_p(ltp);
+
+ if (xfs_has_crc(sc->mp)) {
+ struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
+
+ if (hdr3->pad != cpu_to_be32(0))
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ }
+
+ /*
+ * There must be enough bestfree slots to cover all the directory data
+ * blocks that we scanned. It is possible for there to be a hole
+ * between the last data block and i_disk_size. This seems like an
+ * oversight to the scrub author, but as we have been writing out
+ * directories like this (and xfs_repair doesn't mind them) for years,
+ * that's what we have to check.
+ */
+ if (bestcount != last_data_db + 1) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+
+ /* Is the leaf count even remotely sane? */
+ if (leafhdr.count > geo->leaf_max_ents) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+
+ /* Leaves and bests don't overlap in leaf format. */
+ if ((char *)&leafhdr.ents[leafhdr.count] > (char *)bestp) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+
+ /* Check hash value order, count stale entries. */
+ for (i = 0; i < leafhdr.count; i++) {
+ hash = be32_to_cpu(leafhdr.ents[i].hashval);
+ if (i > 0 && lasthash > hash)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ lasthash = hash;
+ if (leafhdr.ents[i].address ==
+ cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
+ stale++;
+ }
+ if (leafhdr.stale != stale)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out;
+
+ /* Check all the bestfree entries. */
+ for (i = 0; i < bestcount; i++, bestp++) {
+ best = be16_to_cpu(*bestp);
+ error = xfs_dir3_data_read(sc->tp, sc->ip,
+ xfs_dir2_db_to_da(args->geo, i),
+ XFS_DABUF_MAP_HOLE_OK,
+ &dbp);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
+ &error))
+ break;
+
+ if (!dbp) {
+ if (best != NULLDATAOFF) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK,
+ lblk);
+ break;
+ }
+ continue;
+ }
+
+ if (best == NULLDATAOFF)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ else
+ xchk_directory_check_freesp(sc, lblk, dbp, best);
+ xfs_trans_brelse(sc->tp, dbp);
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ break;
+ }
+out:
+ xfs_trans_brelse(sc->tp, bp);
+ return error;
+}
+
+/* Check free space info in a directory freespace block. */
+STATIC int
+xchk_directory_free_bestfree(
+ struct xfs_scrub *sc,
+ struct xfs_da_args *args,
+ xfs_dablk_t lblk)
+{
+ struct xfs_dir3_icfree_hdr freehdr;
+ struct xfs_buf *dbp;
+ struct xfs_buf *bp;
+ __u16 best;
+ unsigned int stale = 0;
+ int i;
+ int error;
+
+ /* Read the free space block */
+ error = xfs_dir2_free_read(sc->tp, sc->ip, lblk, &bp);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
+ return error;
+ xchk_buffer_recheck(sc, bp);
+
+ if (xfs_has_crc(sc->mp)) {
+ struct xfs_dir3_free_hdr *hdr3 = bp->b_addr;
+
+ if (hdr3->pad != cpu_to_be32(0))
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ }
+
+ /* Check all the entries. */
+ xfs_dir2_free_hdr_from_disk(sc->ip->i_mount, &freehdr, bp->b_addr);
+ for (i = 0; i < freehdr.nvalid; i++) {
+ best = be16_to_cpu(freehdr.bests[i]);
+ if (best == NULLDATAOFF) {
+ stale++;
+ continue;
+ }
+ error = xfs_dir3_data_read(sc->tp, sc->ip,
+ (freehdr.firstdb + i) * args->geo->fsbcount,
+ 0, &dbp);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
+ &error))
+ goto out;
+ xchk_directory_check_freesp(sc, lblk, dbp, best);
+ xfs_trans_brelse(sc->tp, dbp);
+ }
+
+ if (freehdr.nused + stale != freehdr.nvalid)
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+out:
+ xfs_trans_brelse(sc->tp, bp);
+ return error;
+}
+
+/* Check free space information in directories. */
+STATIC int
+xchk_directory_blocks(
+ struct xfs_scrub *sc)
+{
+ struct xfs_bmbt_irec got;
+ struct xfs_da_args args;
+ struct xfs_ifork *ifp = xfs_ifork_ptr(sc->ip, XFS_DATA_FORK);
+ struct xfs_mount *mp = sc->mp;
+ xfs_fileoff_t leaf_lblk;
+ xfs_fileoff_t free_lblk;
+ xfs_fileoff_t lblk;
+ struct xfs_iext_cursor icur;
+ xfs_dablk_t dabno;
+ xfs_dir2_db_t last_data_db = 0;
+ bool found;
+ bool is_block = false;
+ int error;
+
+ /* Ignore local format directories. */
+ if (ifp->if_format != XFS_DINODE_FMT_EXTENTS &&
+ ifp->if_format != XFS_DINODE_FMT_BTREE)
+ return 0;
+
+ lblk = XFS_B_TO_FSB(mp, XFS_DIR2_DATA_OFFSET);
+ leaf_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_LEAF_OFFSET);
+ free_lblk = XFS_B_TO_FSB(mp, XFS_DIR2_FREE_OFFSET);
+
+ /* Is this a block dir? */
+ args.dp = sc->ip;
+ args.geo = mp->m_dir_geo;
+ args.trans = sc->tp;
+ error = xfs_dir2_isblock(&args, &is_block);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
+ goto out;
+
+ /* Iterate all the data extents in the directory... */
+ found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
+ while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
+ /* No more data blocks... */
+ if (got.br_startoff >= leaf_lblk)
+ break;
+
+ /*
+ * Check each data block's bestfree data.
+ *
+ * Iterate all the fsbcount-aligned block offsets in
+ * this directory. The directory block reading code is
+ * smart enough to do its own bmap lookups to handle
+ * discontiguous directory blocks. When we're done
+ * with the extent record, re-query the bmap at the
+ * next fsbcount-aligned offset to avoid redundant
+ * block checks.
+ */
+ for (lblk = roundup((xfs_dablk_t)got.br_startoff,
+ args.geo->fsbcount);
+ lblk < got.br_startoff + got.br_blockcount;
+ lblk += args.geo->fsbcount) {
+ last_data_db = xfs_dir2_da_to_db(args.geo, lblk);
+ error = xchk_directory_data_bestfree(sc, lblk,
+ is_block);
+ if (error)
+ goto out;
+ }
+ dabno = got.br_startoff + got.br_blockcount;
+ lblk = roundup(dabno, args.geo->fsbcount);
+ found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
+ }
+
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out;
+
+ /* Look for a leaf1 block, which has free info. */
+ if (xfs_iext_lookup_extent(sc->ip, ifp, leaf_lblk, &icur, &got) &&
+ got.br_startoff == leaf_lblk &&
+ got.br_blockcount == args.geo->fsbcount &&
+ !xfs_iext_next_extent(ifp, &icur, &got)) {
+ if (is_block) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+ error = xchk_directory_leaf1_bestfree(sc, &args, last_data_db,
+ leaf_lblk);
+ if (error)
+ goto out;
+ }
+
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ goto out;
+
+ /* Scan for free blocks */
+ lblk = free_lblk;
+ found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
+ while (found && !(sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
+ /*
+ * Dirs can't have blocks mapped above 2^32.
+ * Single-block dirs shouldn't even be here.
+ */
+ lblk = got.br_startoff;
+ if (lblk & ~0xFFFFFFFFULL) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+ if (is_block) {
+ xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, lblk);
+ goto out;
+ }
+
+ /*
+ * Check each dir free block's bestfree data.
+ *
+ * Iterate all the fsbcount-aligned block offsets in
+ * this directory. The directory block reading code is
+ * smart enough to do its own bmap lookups to handle
+ * discontiguous directory blocks. When we're done
+ * with the extent record, re-query the bmap at the
+ * next fsbcount-aligned offset to avoid redundant
+ * block checks.
+ */
+ for (lblk = roundup((xfs_dablk_t)got.br_startoff,
+ args.geo->fsbcount);
+ lblk < got.br_startoff + got.br_blockcount;
+ lblk += args.geo->fsbcount) {
+ error = xchk_directory_free_bestfree(sc, &args,
+ lblk);
+ if (error)
+ goto out;
+ }
+ dabno = got.br_startoff + got.br_blockcount;
+ lblk = roundup(dabno, args.geo->fsbcount);
+ found = xfs_iext_lookup_extent(sc->ip, ifp, lblk, &icur, &got);
+ }
+out:
+ return error;
+}
+
+/* Scrub a whole directory. */
+int
+xchk_directory(
+ struct xfs_scrub *sc)
+{
+ struct xchk_dir_ctx sdc = {
+ .dir_iter.actor = xchk_dir_actor,
+ .dir_iter.pos = 0,
+ .sc = sc,
+ };
+ size_t bufsize;
+ loff_t oldpos;
+ int error = 0;
+
+ if (!S_ISDIR(VFS_I(sc->ip)->i_mode))
+ return -ENOENT;
+
+ /* Plausible size? */
+ if (sc->ip->i_disk_size < xfs_dir2_sf_hdr_size(0)) {
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ goto out;
+ }
+
+ /* Check directory tree structure */
+ error = xchk_da_btree(sc, XFS_DATA_FORK, xchk_dir_rec, NULL);
+ if (error)
+ return error;
+
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ return error;
+
+ /* Check the freespace. */
+ error = xchk_directory_blocks(sc);
+ if (error)
+ return error;
+
+ if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
+ return error;
+
+ /*
+ * Check that every dirent we see can also be looked up by hash.
+ * Userspace usually asks for a 32k buffer, so we will too.
+ */
+ bufsize = (size_t)min_t(loff_t, XFS_READDIR_BUFSIZE,
+ sc->ip->i_disk_size);
+
+ /*
+ * Look up every name in this directory by hash.
+ *
+ * Use the xfs_readdir function to call xchk_dir_actor on
+ * every directory entry in this directory. In _actor, we check
+ * the name, inode number, and ftype (if applicable) of the
+ * entry. xfs_readdir uses the VFS filldir functions to provide
+ * iteration context.
+ *
+ * The VFS grabs a read or write lock via i_rwsem before it reads
+ * or writes to a directory. If we've gotten this far we've
+ * already obtained IOLOCK_EXCL, which (since 4.10) is the same as
+ * getting a write lock on i_rwsem. Therefore, it is safe for us
+ * to drop the ILOCK here in order to reuse the _readdir and
+ * _dir_lookup routines, which do their own ILOCK locking.
+ */
+ oldpos = 0;
+ sc->ilock_flags &= ~XFS_ILOCK_EXCL;
+ xfs_iunlock(sc->ip, XFS_ILOCK_EXCL);
+ while (true) {
+ error = xfs_readdir(sc->tp, sc->ip, &sdc.dir_iter, bufsize);
+ if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0,
+ &error))
+ goto out;
+ if (oldpos == sdc.dir_iter.pos)
+ break;
+ oldpos = sdc.dir_iter.pos;
+ }
+
+out:
+ return error;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-09 19:17:52 +0000