Commit c4e34172 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: standardize ondisk to incore conversion for rmap btrees 



Create a xfs_rmap_check_irec function to detect corruption in btree
records.  Fix all xfs_rmap_btrec_to_irec callsites to call the new
helper and bubble up corruption reports.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent 39ab26d5

fs/xfs/libxfs/xfs_rmap.c

+39 −23
Original line number Diff line number Diff line
@@ -205,6 +205,36 @@ xfs_rmap_btrec_to_irec( 
			irec);

}



/* Simple checks for rmap records. */

xfs_failaddr_t

xfs_rmap_check_irec(

	struct xfs_btree_cur		*cur,

	const struct xfs_rmap_irec	*irec)

{

	struct xfs_mount		*mp = cur->bc_mp;



	if (irec->rm_blockcount == 0)

		return __this_address;

	if (irec->rm_startblock <= XFS_AGFL_BLOCK(mp)) {

		if (irec->rm_owner != XFS_RMAP_OWN_FS)

			return __this_address;

		if (irec->rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)

			return __this_address;

	} else {

		/* check for valid extent range, including overflow */

		if (!xfs_verify_agbext(cur->bc_ag.pag, irec->rm_startblock,

						       irec->rm_blockcount))

			return __this_address;

	}



	if (!(xfs_verify_ino(mp, irec->rm_owner) ||

	      (irec->rm_owner <= XFS_RMAP_OWN_FS &&

	       irec->rm_owner >= XFS_RMAP_OWN_MIN)))

		return __this_address;



	return NULL;

}



/*

 * Get the data from the pointed-to record.

 */
@@ -217,39 +247,24 @@ xfs_rmap_get_rec( 
	struct xfs_mount	*mp = cur->bc_mp;

	struct xfs_perag	*pag = cur->bc_ag.pag;

	union xfs_btree_rec	*rec;

	xfs_failaddr_t		fa;

	int			error;



	error = xfs_btree_get_rec(cur, &rec, stat);

	if (error || !*stat)

		return error;



	if (xfs_rmap_btrec_to_irec(rec, irec))

		goto out_bad_rec;



	if (irec->rm_blockcount == 0)

		goto out_bad_rec;

	if (irec->rm_startblock <= XFS_AGFL_BLOCK(mp)) {

		if (irec->rm_owner != XFS_RMAP_OWN_FS)

			goto out_bad_rec;

		if (irec->rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)

			goto out_bad_rec;

	} else {

		/* check for valid extent range, including overflow */

		if (!xfs_verify_agbext(pag, irec->rm_startblock,

					    irec->rm_blockcount))

			goto out_bad_rec;

	}



	if (!(xfs_verify_ino(mp, irec->rm_owner) ||

	      (irec->rm_owner <= XFS_RMAP_OWN_FS &&

	       irec->rm_owner >= XFS_RMAP_OWN_MIN)))

	fa = xfs_rmap_btrec_to_irec(rec, irec);

	if (!fa)

		fa = xfs_rmap_check_irec(cur, irec);

	if (fa)

		goto out_bad_rec;



	return 0;

out_bad_rec:

	xfs_warn(mp,

		"Reverse Mapping BTree record corruption in AG %d detected!",

		pag->pag_agno);

		"Reverse Mapping BTree record corruption in AG %d detected at %pS!",

		pag->pag_agno, fa);

	xfs_warn(mp,

		"Owner 0x%llx, flags 0x%x, start block 0x%x block count 0x%x",

		irec->rm_owner, irec->rm_flags, irec->rm_startblock,
@@ -2321,7 +2336,8 @@ xfs_rmap_query_range_helper( 
	struct xfs_rmap_query_range_info	*query = priv;

	struct xfs_rmap_irec			irec;



	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL)

	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL ||

	    xfs_rmap_check_irec(cur, &irec) != NULL)

		return -EFSCORRUPTED;



	return query->fn(cur, &irec, query->priv);

fs/xfs/libxfs/xfs_rmap.h

+3 −0
Original line number Diff line number Diff line
@@ -195,6 +195,9 @@ int xfs_rmap_compare(const struct xfs_rmap_irec *a, 
union xfs_btree_rec;

xfs_failaddr_t xfs_rmap_btrec_to_irec(const union xfs_btree_rec *rec,

		struct xfs_rmap_irec *irec);

xfs_failaddr_t xfs_rmap_check_irec(struct xfs_btree_cur *cur,

		const struct xfs_rmap_irec *irec);



int xfs_rmap_has_record(struct xfs_btree_cur *cur, xfs_agblock_t bno,

		xfs_extlen_t len, bool *exists);

int xfs_rmap_record_exists(struct xfs_btree_cur *cur, xfs_agblock_t bno,

fs/xfs/scrub/rmap.c

+2 −37
Original line number Diff line number Diff line
@@ -93,43 +93,18 @@ xchk_rmapbt_rec( 
	struct xchk_btree	*bs,

	const union xfs_btree_rec *rec)

{

	struct xfs_mount	*mp = bs->cur->bc_mp;

	struct xfs_rmap_irec	irec;

	struct xfs_perag	*pag = bs->cur->bc_ag.pag;

	bool			non_inode;

	bool			is_unwritten;

	bool			is_bmbt;

	bool			is_attr;



	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL) {

	if (xfs_rmap_btrec_to_irec(rec, &irec) != NULL ||

	    xfs_rmap_check_irec(bs->cur, &irec) != NULL) {

		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);

		return 0;

	}



	/* Check extent. */

	if (irec.rm_startblock + irec.rm_blockcount <= irec.rm_startblock)

		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (irec.rm_owner == XFS_RMAP_OWN_FS) {

		/*

		 * xfs_verify_agbno returns false for static fs metadata.

		 * Since that only exists at the start of the AG, validate

		 * that by hand.

		 */

		if (irec.rm_startblock != 0 ||

		    irec.rm_blockcount != XFS_AGFL_BLOCK(mp) + 1)

			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);

	} else {

		/*

		 * Otherwise we must point somewhere past the static metadata

		 * but before the end of the FS.  Run the regular check.

		 */

		if (!xfs_verify_agbno(pag, irec.rm_startblock) ||

		    !xfs_verify_agbno(pag, irec.rm_startblock +

				irec.rm_blockcount - 1))

			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);

	}



	/* Check flags. */

	non_inode = XFS_RMAP_NON_INODE_OWNER(irec.rm_owner);

	is_bmbt = irec.rm_flags & XFS_RMAP_BMBT_BLOCK;
@@ -148,16 +123,6 @@ xchk_rmapbt_rec( 
	if (non_inode && (is_bmbt || is_unwritten || is_attr))

		xchk_btree_set_corrupt(bs->sc, bs->cur, 0);



	if (!non_inode) {

		if (!xfs_verify_ino(mp, irec.rm_owner))

			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);

	} else {

		/* Non-inode owner within the magic values? */

		if (irec.rm_owner <= XFS_RMAP_OWN_MIN ||

		    irec.rm_owner > XFS_RMAP_OWN_FS)

			xchk_btree_set_corrupt(bs->sc, bs->cur, 0);

	}



	xchk_rmapbt_xref(bs->sc, &irec);

	return 0;

}