xfs: validate explicit directory data buffer owners

Port the existing directory data header checking function to accept an
owner number instead of an xfs_inode, then update the callsites to use
xfs_da_args.owner when possible.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_dir2.h

@@ -102,6 +102,7 @@ extern struct xfs_dir2_data_free *xfs_dir2_data_freefind(
 extern int xfs_dir_ino_validate(struct xfs_mount *mp, xfs_ino_t ino);
 
 xfs_failaddr_t xfs_dir3_leaf_header_check(struct xfs_buf *bp, xfs_ino_t owner);
+xfs_failaddr_t xfs_dir3_data_header_check(struct xfs_buf *bp, xfs_ino_t owner);
 
 extern const struct xfs_buf_ops xfs_dir3_block_buf_ops;
 extern const struct xfs_buf_ops xfs_dir3_leafn_buf_ops;

fs/xfs/libxfs/xfs_dir2_block.c

@@ -982,7 +982,8 @@ xfs_dir2_leaf_to_block(
 	 * Read the data block if we don't already have it, give up if it fails.
 	 */
 	if (!dbp) {
-		error = xfs_dir3_data_read(tp, dp, args->geo->datablk, 0, &dbp);
+		error = xfs_dir3_data_read(tp, dp, args->owner,
+				args->geo->datablk, 0, &dbp);
 		if (error)
 			return error;
 	}

fs/xfs/libxfs/xfs_dir2_data.c

@@ -395,17 +395,20 @@ static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = {
 	.verify_write = xfs_dir3_data_write_verify,
 };
 
-static xfs_failaddr_t
+xfs_failaddr_t
 xfs_dir3_data_header_check(
-	struct xfs_inode	*dp,
-	struct xfs_buf		*bp)
+	struct xfs_buf		*bp,
+	xfs_ino_t		owner)
 {
-	struct xfs_mount	*mp = dp->i_mount;
+	struct xfs_mount	*mp = bp->b_mount;
 
 	if (xfs_has_crc(mp)) {
 		struct xfs_dir3_data_hdr *hdr3 = bp->b_addr;
 
-		if (be64_to_cpu(hdr3->hdr.owner) != dp->i_ino)
+		if (hdr3->hdr.magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC))
+			return __this_address;
+
+		if (be64_to_cpu(hdr3->hdr.owner) != owner)
 			return __this_address;
 	}
 
@@ -416,6 +419,7 @@ int
 xfs_dir3_data_read(
 	struct xfs_trans	*tp,
 	struct xfs_inode	*dp,
+	xfs_ino_t		owner,
 	xfs_dablk_t		bno,
 	unsigned int		flags,
 	struct xfs_buf		**bpp)
@@ -429,7 +433,7 @@ xfs_dir3_data_read(
 		return err;
 
 	/* Check things that we can't do in the verifier. */
-	fa = xfs_dir3_data_header_check(dp, *bpp);
+	fa = xfs_dir3_data_header_check(*bpp, owner);
 	if (fa) {
 		__xfs_buf_mark_corrupt(*bpp, fa);
 		xfs_trans_brelse(tp, *bpp);

fs/xfs/libxfs/xfs_dir2_leaf.c

@@ -885,9 +885,9 @@ xfs_dir2_leaf_addname(
 		 * Already had space in some data block.
 		 * Just read that one in.
 		 */
-		error = xfs_dir3_data_read(tp, dp,
-				   xfs_dir2_db_to_da(args->geo, use_block),
-				   0, &dbp);
+		error = xfs_dir3_data_read(tp, dp, args->owner,
+				xfs_dir2_db_to_da(args->geo, use_block), 0,
+				&dbp);
 		if (error) {
 			xfs_trans_brelse(tp, lbp);
 			return error;
@@ -1328,9 +1328,9 @@ xfs_dir2_leaf_lookup_int(
 		if (newdb != curdb) {
 			if (dbp)
 				xfs_trans_brelse(tp, dbp);
-			error = xfs_dir3_data_read(tp, dp,
-					   xfs_dir2_db_to_da(args->geo, newdb),
-					   0, &dbp);
+			error = xfs_dir3_data_read(tp, dp, args->owner,
+					xfs_dir2_db_to_da(args->geo, newdb), 0,
+					&dbp);
 			if (error) {
 				xfs_trans_brelse(tp, lbp);
 				return error;
@@ -1370,9 +1370,9 @@ xfs_dir2_leaf_lookup_int(
 		ASSERT(cidb != -1);
 		if (cidb != curdb) {
 			xfs_trans_brelse(tp, dbp);
-			error = xfs_dir3_data_read(tp, dp,
-					   xfs_dir2_db_to_da(args->geo, cidb),
-					   0, &dbp);
+			error = xfs_dir3_data_read(tp, dp, args->owner,
+					xfs_dir2_db_to_da(args->geo, cidb), 0,
+					&dbp);
 			if (error) {
 				xfs_trans_brelse(tp, lbp);
 				return error;
@@ -1666,7 +1666,8 @@ xfs_dir2_leaf_trim_data(
 	/*
 	 * Read the offending data block.  We need its buffer.
 	 */
-	error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(geo, db), 0, &dbp);
+	error = xfs_dir3_data_read(tp, dp, args->owner,
+			xfs_dir2_db_to_da(geo, db), 0, &dbp);
 	if (error)
 		return error;
 

fs/xfs/libxfs/xfs_dir2_node.c

@@ -863,7 +863,7 @@ xfs_dir2_leafn_lookup_for_entry(
 				ASSERT(state->extravalid);
 				curbp = state->extrablk.bp;
 			} else {
-				error = xfs_dir3_data_read(tp, dp,
+				error = xfs_dir3_data_read(tp, dp, args->owner,
 						xfs_dir2_db_to_da(args->geo,
 								  newdb),
 						0, &curbp);
@@ -1949,9 +1949,8 @@ xfs_dir2_node_addname_int(
 						  &freehdr, &findex);
 	} else {
 		/* Read the data block in. */
-		error = xfs_dir3_data_read(tp, dp,
-					   xfs_dir2_db_to_da(args->geo, dbno),
-					   0, &dbp);
+		error = xfs_dir3_data_read(tp, dp, args->owner,
+				xfs_dir2_db_to_da(args->geo, dbno), 0, &dbp);
 	}
 	if (error)
 		return error;

fs/xfs/libxfs/xfs_dir2_priv.h

@@ -78,7 +78,8 @@ extern void xfs_dir3_data_check(struct xfs_inode *dp, struct xfs_buf *bp);
 extern xfs_failaddr_t __xfs_dir3_data_check(struct xfs_inode *dp,
 		struct xfs_buf *bp);
 int xfs_dir3_data_read(struct xfs_trans *tp, struct xfs_inode *dp,
-		xfs_dablk_t bno, unsigned int flags, struct xfs_buf **bpp);
+		xfs_ino_t owner, xfs_dablk_t bno, unsigned int flags,
+		struct xfs_buf **bpp);
 int xfs_dir3_data_readahead(struct xfs_inode *dp, xfs_dablk_t bno,
 		unsigned int flags);
 

fs/xfs/scrub/dir.c

@@ -196,8 +196,8 @@ xchk_dir_rec(
 		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);
+	error = xfs_dir3_data_read(ds->dargs.trans, dp, ds->dargs.owner,
+			rec_bno, XFS_DABUF_MAP_HOLE_OK, &bp);
 	if (!xchk_fblock_process_error(ds->sc, XFS_DATA_FORK, rec_bno,
 			&error))
 		goto out;
@@ -318,7 +318,8 @@ xchk_directory_data_bestfree(
 		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);
+		error = xfs_dir3_data_read(sc->tp, sc->ip, sc->ip->i_ino, lblk,
+				0, &bp);
 	}
 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk, &error))
 		goto out;
@@ -531,10 +532,9 @@ xchk_directory_leaf1_bestfree(
 	/* 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,
+		error = xfs_dir3_data_read(sc->tp, sc->ip, args->owner,
 				xfs_dir2_db_to_da(args->geo, i),
-				XFS_DABUF_MAP_HOLE_OK,
-				&dbp);
+				XFS_DABUF_MAP_HOLE_OK, &dbp);
 		if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,
 				&error))
 			break;
@@ -597,7 +597,7 @@ xchk_directory_free_bestfree(
 			stale++;
 			continue;
 		}
-		error = xfs_dir3_data_read(sc->tp, sc->ip,
+		error = xfs_dir3_data_read(sc->tp, sc->ip, args->owner,
 				(freehdr.firstdb + i) * args->geo->fsbcount,
 				0, &dbp);
 		if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, lblk,

fs/xfs/scrub/readdir.c

@@ -175,7 +175,7 @@ xchk_read_leaf_dir_buf(
 	if (new_off > *curoff)
 		*curoff = new_off;
 
-	return xfs_dir3_data_read(tp, dp, map.br_startoff, 0, bpp);
+	return xfs_dir3_data_read(tp, dp, dp->i_ino, map.br_startoff, 0, bpp);
 }
 
 /* Call a function for every entry in a leaf directory. */

fs/xfs/xfs_dir2_readdir.c

@@ -282,7 +282,8 @@ xfs_dir2_leaf_readbuf(
 	new_off = xfs_dir2_da_to_byte(geo, map.br_startoff);
 	if (new_off > *cur_off)
 		*cur_off = new_off;
-	error = xfs_dir3_data_read(args->trans, dp, map.br_startoff, 0, &bp);
+	error = xfs_dir3_data_read(args->trans, dp, args->owner,
+			map.br_startoff, 0, &bp);
 	if (error)
 		goto out;