brintos

brintos / linux-shallow public Read only

0
0
Text · 7.4 KiB · 256ff77 Raw
321 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) 2022-2024 Oracle.  All Rights Reserved.4 * Author: Darrick J. Wong <djwong@kernel.org>5 */6#include "xfs.h"7#include "xfs_fs.h"8#include "xfs_shared.h"9#include "xfs_format.h"10#include "xfs_log_format.h"11#include "xfs_trans_resv.h"12#include "xfs_mount.h"13#include "xfs_inode.h"14#include "xfs_da_format.h"15#include "xfs_da_btree.h"16#include "xfs_attr.h"17#include "xfs_attr_leaf.h"18#include "xfs_attr_sf.h"19#include "xfs_trans.h"20#include "scrub/scrub.h"21#include "scrub/bitmap.h"22#include "scrub/dab_bitmap.h"23#include "scrub/listxattr.h"24 25/* Call a function for every entry in a shortform xattr structure. */26STATIC int27xchk_xattr_walk_sf(28	struct xfs_scrub		*sc,29	struct xfs_inode		*ip,30	xchk_xattr_fn			attr_fn,31	void				*priv)32{33	struct xfs_attr_sf_hdr		*hdr = ip->i_af.if_data;34	struct xfs_attr_sf_entry	*sfe;35	unsigned int			i;36	int				error;37 38	sfe = xfs_attr_sf_firstentry(hdr);39	for (i = 0; i < hdr->count; i++) {40		error = attr_fn(sc, ip, sfe->flags, sfe->nameval, sfe->namelen,41				&sfe->nameval[sfe->namelen], sfe->valuelen,42				priv);43		if (error)44			return error;45 46		sfe = xfs_attr_sf_nextentry(sfe);47	}48 49	return 0;50}51 52/* Call a function for every entry in this xattr leaf block. */53STATIC int54xchk_xattr_walk_leaf_entries(55	struct xfs_scrub		*sc,56	struct xfs_inode		*ip,57	xchk_xattr_fn			attr_fn,58	struct xfs_buf			*bp,59	void				*priv)60{61	struct xfs_attr3_icleaf_hdr	ichdr;62	struct xfs_mount		*mp = sc->mp;63	struct xfs_attr_leafblock	*leaf = bp->b_addr;64	struct xfs_attr_leaf_entry	*entry;65	unsigned int			i;66	int				error;67 68	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);69	entry = xfs_attr3_leaf_entryp(leaf);70 71	for (i = 0; i < ichdr.count; entry++, i++) {72		void			*value;73		unsigned char		*name;74		unsigned int		namelen, valuelen;75 76		if (entry->flags & XFS_ATTR_LOCAL) {77			struct xfs_attr_leaf_name_local		*name_loc;78 79			name_loc = xfs_attr3_leaf_name_local(leaf, i);80			name = name_loc->nameval;81			namelen = name_loc->namelen;82			value = &name_loc->nameval[name_loc->namelen];83			valuelen = be16_to_cpu(name_loc->valuelen);84		} else {85			struct xfs_attr_leaf_name_remote	*name_rmt;86 87			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);88			name = name_rmt->name;89			namelen = name_rmt->namelen;90			value = NULL;91			valuelen = be32_to_cpu(name_rmt->valuelen);92		}93 94		error = attr_fn(sc, ip, entry->flags, name, namelen, value,95				valuelen, priv);96		if (error)97			return error;98 99	}100 101	return 0;102}103 104/*105 * Call a function for every entry in a leaf-format xattr structure.  Avoid106 * memory allocations for the loop detector since there's only one block.107 */108STATIC int109xchk_xattr_walk_leaf(110	struct xfs_scrub		*sc,111	struct xfs_inode		*ip,112	xchk_xattr_fn			attr_fn,113	void				*priv)114{115	struct xfs_buf			*leaf_bp;116	int				error;117 118	error = xfs_attr3_leaf_read(sc->tp, ip, ip->i_ino, 0, &leaf_bp);119	if (error)120		return error;121 122	error = xchk_xattr_walk_leaf_entries(sc, ip, attr_fn, leaf_bp, priv);123	xfs_trans_brelse(sc->tp, leaf_bp);124	return error;125}126 127/* Find the leftmost leaf in the xattr dabtree. */128STATIC int129xchk_xattr_find_leftmost_leaf(130	struct xfs_scrub		*sc,131	struct xfs_inode		*ip,132	struct xdab_bitmap		*seen_dablks,133	struct xfs_buf			**leaf_bpp)134{135	struct xfs_da3_icnode_hdr	nodehdr;136	struct xfs_mount		*mp = sc->mp;137	struct xfs_trans		*tp = sc->tp;138	struct xfs_da_intnode		*node;139	struct xfs_da_node_entry	*btree;140	struct xfs_buf			*bp;141	xfs_failaddr_t			fa;142	xfs_dablk_t			blkno = 0;143	unsigned int			expected_level = 0;144	int				error;145 146	for (;;) {147		xfs_extlen_t		len = 1;148		uint16_t		magic;149 150		/* Make sure we haven't seen this new block already. */151		if (xdab_bitmap_test(seen_dablks, blkno, &len))152			return -EFSCORRUPTED;153 154		error = xfs_da3_node_read(tp, ip, blkno, &bp, XFS_ATTR_FORK);155		if (error)156			return error;157 158		node = bp->b_addr;159		magic = be16_to_cpu(node->hdr.info.magic);160		if (magic == XFS_ATTR_LEAF_MAGIC ||161		    magic == XFS_ATTR3_LEAF_MAGIC)162			break;163 164		error = -EFSCORRUPTED;165		if (magic != XFS_DA_NODE_MAGIC &&166		    magic != XFS_DA3_NODE_MAGIC)167			goto out_buf;168 169		fa = xfs_da3_node_header_check(bp, ip->i_ino);170		if (fa)171			goto out_buf;172 173		xfs_da3_node_hdr_from_disk(mp, &nodehdr, node);174 175		if (nodehdr.count == 0 || nodehdr.level >= XFS_DA_NODE_MAXDEPTH)176			goto out_buf;177 178		/* Check the level from the root node. */179		if (blkno == 0)180			expected_level = nodehdr.level - 1;181		else if (expected_level != nodehdr.level)182			goto out_buf;183		else184			expected_level--;185 186		/* Remember that we've seen this node. */187		error = xdab_bitmap_set(seen_dablks, blkno, 1);188		if (error)189			goto out_buf;190 191		/* Find the next level towards the leaves of the dabtree. */192		btree = nodehdr.btree;193		blkno = be32_to_cpu(btree->before);194		xfs_trans_brelse(tp, bp);195	}196 197	error = -EFSCORRUPTED;198	fa = xfs_attr3_leaf_header_check(bp, ip->i_ino);199	if (fa)200		goto out_buf;201 202	if (expected_level != 0)203		goto out_buf;204 205	/* Remember that we've seen this leaf. */206	error = xdab_bitmap_set(seen_dablks, blkno, 1);207	if (error)208		goto out_buf;209 210	*leaf_bpp = bp;211	return 0;212 213out_buf:214	xfs_trans_brelse(tp, bp);215	return error;216}217 218/* Call a function for every entry in a node-format xattr structure. */219STATIC int220xchk_xattr_walk_node(221	struct xfs_scrub		*sc,222	struct xfs_inode		*ip,223	xchk_xattr_fn			attr_fn,224	xchk_xattrleaf_fn		leaf_fn,225	void				*priv)226{227	struct xfs_attr3_icleaf_hdr	leafhdr;228	struct xdab_bitmap		seen_dablks;229	struct xfs_mount		*mp = sc->mp;230	struct xfs_attr_leafblock	*leaf;231	struct xfs_buf			*leaf_bp;232	int				error;233 234	xdab_bitmap_init(&seen_dablks);235 236	error = xchk_xattr_find_leftmost_leaf(sc, ip, &seen_dablks, &leaf_bp);237	if (error)238		goto out_bitmap;239 240	for (;;) {241		xfs_extlen_t	len;242 243		error = xchk_xattr_walk_leaf_entries(sc, ip, attr_fn, leaf_bp,244				priv);245		if (error)246			goto out_leaf;247 248		/* Find the right sibling of this leaf block. */249		leaf = leaf_bp->b_addr;250		xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);251		if (leafhdr.forw == 0)252			goto out_leaf;253 254		xfs_trans_brelse(sc->tp, leaf_bp);255 256		if (leaf_fn) {257			error = leaf_fn(sc, priv);258			if (error)259				goto out_bitmap;260		}261 262		/* Make sure we haven't seen this new leaf already. */263		len = 1;264		if (xdab_bitmap_test(&seen_dablks, leafhdr.forw, &len)) {265			error = -EFSCORRUPTED;266			goto out_bitmap;267		}268 269		error = xfs_attr3_leaf_read(sc->tp, ip, ip->i_ino,270				leafhdr.forw, &leaf_bp);271		if (error)272			goto out_bitmap;273 274		/* Remember that we've seen this new leaf. */275		error = xdab_bitmap_set(&seen_dablks, leafhdr.forw, 1);276		if (error)277			goto out_leaf;278	}279 280out_leaf:281	xfs_trans_brelse(sc->tp, leaf_bp);282out_bitmap:283	xdab_bitmap_destroy(&seen_dablks);284	return error;285}286 287/*288 * Call a function for every extended attribute in a file.289 *290 * Callers must hold the ILOCK.  No validation or cursor restarts allowed.291 * Returns -EFSCORRUPTED on any problem, including loops in the dabtree.292 */293int294xchk_xattr_walk(295	struct xfs_scrub	*sc,296	struct xfs_inode	*ip,297	xchk_xattr_fn		attr_fn,298	xchk_xattrleaf_fn	leaf_fn,299	void			*priv)300{301	int			error;302 303	xfs_assert_ilocked(ip, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL);304 305	if (!xfs_inode_hasattr(ip))306		return 0;307 308	if (ip->i_af.if_format == XFS_DINODE_FMT_LOCAL)309		return xchk_xattr_walk_sf(sc, ip, attr_fn, priv);310 311	/* attr functions require that the attr fork is loaded */312	error = xfs_iread_extents(sc->tp, ip, XFS_ATTR_FORK);313	if (error)314		return error;315 316	if (xfs_attr_is_leaf(ip))317		return xchk_xattr_walk_leaf(sc, ip, attr_fn, priv);318 319	return xchk_xattr_walk_node(sc, ip, attr_fn, leaf_fn, priv);320}321