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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.4 * Copyright (c) 2013 Red Hat, Inc.5 * All Rights Reserved.6 */7#include "xfs.h"8#include "xfs_fs.h"9#include "xfs_shared.h"10#include "xfs_format.h"11#include "xfs_log_format.h"12#include "xfs_trans_resv.h"13#include "xfs_mount.h"14#include "xfs_da_format.h"15#include "xfs_inode.h"16#include "xfs_trans.h"17#include "xfs_bmap.h"18#include "xfs_da_btree.h"19#include "xfs_attr.h"20#include "xfs_attr_sf.h"21#include "xfs_attr_leaf.h"22#include "xfs_error.h"23#include "xfs_trace.h"24#include "xfs_dir2.h"25#include "xfs_health.h"26 27STATIC int28xfs_attr_shortform_compare(const void *a, const void *b)29{30	xfs_attr_sf_sort_t *sa, *sb;31 32	sa = (xfs_attr_sf_sort_t *)a;33	sb = (xfs_attr_sf_sort_t *)b;34	if (sa->hash < sb->hash) {35		return -1;36	} else if (sa->hash > sb->hash) {37		return 1;38	} else {39		return sa->entno - sb->entno;40	}41}42 43#define XFS_ISRESET_CURSOR(cursor) \44	(!((cursor)->initted) && !((cursor)->hashval) && \45	 !((cursor)->blkno) && !((cursor)->offset))46/*47 * Copy out entries of shortform attribute lists for attr_list().48 * Shortform attribute lists are not stored in hashval sorted order.49 * If the output buffer is not large enough to hold them all, then50 * we have to calculate each entries' hashvalue and sort them before51 * we can begin returning them to the user.52 */53static int54xfs_attr_shortform_list(55	struct xfs_attr_list_context	*context)56{57	struct xfs_attrlist_cursor_kern	*cursor = &context->cursor;58	struct xfs_inode		*dp = context->dp;59	struct xfs_attr_sf_sort		*sbuf, *sbp;60	struct xfs_attr_sf_hdr		*sf = dp->i_af.if_data;61	struct xfs_attr_sf_entry	*sfe;62	int				sbsize, nsbuf, count, i;63	int				error = 0;64 65	ASSERT(sf != NULL);66	if (!sf->count)67		return 0;68 69	trace_xfs_attr_list_sf(context);70 71	/*72	 * If the buffer is large enough and the cursor is at the start,73	 * do not bother with sorting since we will return everything in74	 * one buffer and another call using the cursor won't need to be75	 * made.76	 * Note the generous fudge factor of 16 overhead bytes per entry.77	 * If bufsize is zero then put_listent must be a search function78	 * and can just scan through what we have.79	 */80	if (context->bufsize == 0 ||81	    (XFS_ISRESET_CURSOR(cursor) &&82	     (dp->i_af.if_bytes + sf->count * 16) < context->bufsize)) {83		for (i = 0, sfe = xfs_attr_sf_firstentry(sf); i < sf->count; i++) {84			if (XFS_IS_CORRUPT(context->dp->i_mount,85					   !xfs_attr_namecheck(sfe->flags,86							       sfe->nameval,87							       sfe->namelen))) {88				xfs_dirattr_mark_sick(context->dp, XFS_ATTR_FORK);89				return -EFSCORRUPTED;90			}91			context->put_listent(context,92					     sfe->flags,93					     sfe->nameval,94					     (int)sfe->namelen,95					     &sfe->nameval[sfe->namelen],96					     (int)sfe->valuelen);97			/*98			 * Either search callback finished early or99			 * didn't fit it all in the buffer after all.100			 */101			if (context->seen_enough)102				break;103			sfe = xfs_attr_sf_nextentry(sfe);104		}105		trace_xfs_attr_list_sf_all(context);106		return 0;107	}108 109	/* do no more for a search callback */110	if (context->bufsize == 0)111		return 0;112 113	/*114	 * It didn't all fit, so we have to sort everything on hashval.115	 */116	sbsize = sf->count * sizeof(*sbuf);117	sbp = sbuf = kmalloc(sbsize, GFP_KERNEL | __GFP_NOFAIL);118 119	/*120	 * Scan the attribute list for the rest of the entries, storing121	 * the relevant info from only those that match into a buffer.122	 */123	nsbuf = 0;124	for (i = 0, sfe = xfs_attr_sf_firstentry(sf); i < sf->count; i++) {125		if (unlikely(126		    ((char *)sfe < (char *)sf) ||127		    ((char *)sfe >= ((char *)sf + dp->i_af.if_bytes)) ||128		    !xfs_attr_check_namespace(sfe->flags))) {129			XFS_CORRUPTION_ERROR("xfs_attr_shortform_list",130					     XFS_ERRLEVEL_LOW,131					     context->dp->i_mount, sfe,132					     sizeof(*sfe));133			kfree(sbuf);134			xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);135			return -EFSCORRUPTED;136		}137 138		sbp->entno = i;139		sbp->name = sfe->nameval;140		sbp->namelen = sfe->namelen;141		/* These are bytes, and both on-disk, don't endian-flip */142		sbp->value = &sfe->nameval[sfe->namelen];143		sbp->valuelen = sfe->valuelen;144		sbp->flags = sfe->flags;145		sbp->hash = xfs_attr_hashval(dp->i_mount, sfe->flags,146					     sfe->nameval, sfe->namelen,147					     sfe->nameval + sfe->namelen,148					     sfe->valuelen);149		sfe = xfs_attr_sf_nextentry(sfe);150		sbp++;151		nsbuf++;152	}153 154	/*155	 * Sort the entries on hash then entno.156	 */157	xfs_sort(sbuf, nsbuf, sizeof(*sbuf), xfs_attr_shortform_compare);158 159	/*160	 * Re-find our place IN THE SORTED LIST.161	 */162	count = 0;163	cursor->initted = 1;164	cursor->blkno = 0;165	for (sbp = sbuf, i = 0; i < nsbuf; i++, sbp++) {166		if (sbp->hash == cursor->hashval) {167			if (cursor->offset == count) {168				break;169			}170			count++;171		} else if (sbp->hash > cursor->hashval) {172			break;173		}174	}175	if (i == nsbuf)176		goto out;177 178	/*179	 * Loop putting entries into the user buffer.180	 */181	for ( ; i < nsbuf; i++, sbp++) {182		if (cursor->hashval != sbp->hash) {183			cursor->hashval = sbp->hash;184			cursor->offset = 0;185		}186		if (XFS_IS_CORRUPT(context->dp->i_mount,187				   !xfs_attr_namecheck(sbp->flags, sbp->name,188						       sbp->namelen))) {189			xfs_dirattr_mark_sick(context->dp, XFS_ATTR_FORK);190			error = -EFSCORRUPTED;191			goto out;192		}193		context->put_listent(context,194				     sbp->flags,195				     sbp->name,196				     sbp->namelen,197				     sbp->value,198				     sbp->valuelen);199		if (context->seen_enough)200			break;201		cursor->offset++;202	}203out:204	kfree(sbuf);205	return error;206}207 208/*209 * We didn't find the block & hash mentioned in the cursor state, so210 * walk down the attr btree looking for the hash.211 */212STATIC int213xfs_attr_node_list_lookup(214	struct xfs_attr_list_context	*context,215	struct xfs_attrlist_cursor_kern	*cursor,216	struct xfs_buf			**pbp)217{218	struct xfs_da3_icnode_hdr	nodehdr;219	struct xfs_da_intnode		*node;220	struct xfs_da_node_entry	*btree;221	struct xfs_inode		*dp = context->dp;222	struct xfs_mount		*mp = dp->i_mount;223	struct xfs_trans		*tp = context->tp;224	struct xfs_buf			*bp;225	xfs_failaddr_t			fa;226	int				i;227	int				error = 0;228	unsigned int			expected_level = 0;229	uint16_t			magic;230 231	ASSERT(*pbp == NULL);232	cursor->blkno = 0;233	for (;;) {234		error = xfs_da3_node_read(tp, dp, cursor->blkno, &bp,235				XFS_ATTR_FORK);236		if (error)237			return error;238		node = bp->b_addr;239		magic = be16_to_cpu(node->hdr.info.magic);240		if (magic == XFS_ATTR_LEAF_MAGIC ||241		    magic == XFS_ATTR3_LEAF_MAGIC)242			break;243		if (magic != XFS_DA_NODE_MAGIC &&244		    magic != XFS_DA3_NODE_MAGIC) {245			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,246					node, sizeof(*node));247			goto out_corruptbuf;248		}249 250		fa = xfs_da3_node_header_check(bp, dp->i_ino);251		if (fa)252			goto out_corruptbuf;253 254		xfs_da3_node_hdr_from_disk(mp, &nodehdr, node);255 256		/* Tree taller than we can handle; bail out! */257		if (nodehdr.level >= XFS_DA_NODE_MAXDEPTH)258			goto out_corruptbuf;259 260		/* Check the level from the root node. */261		if (cursor->blkno == 0)262			expected_level = nodehdr.level - 1;263		else if (expected_level != nodehdr.level)264			goto out_corruptbuf;265		else266			expected_level--;267 268		btree = nodehdr.btree;269		for (i = 0; i < nodehdr.count; btree++, i++) {270			if (cursor->hashval <= be32_to_cpu(btree->hashval)) {271				cursor->blkno = be32_to_cpu(btree->before);272				trace_xfs_attr_list_node_descend(context,273						btree);274				break;275			}276		}277		xfs_trans_brelse(tp, bp);278 279		if (i == nodehdr.count)280			return 0;281 282		/* We can't point back to the root. */283		if (XFS_IS_CORRUPT(mp, cursor->blkno == 0)) {284			xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);285			return -EFSCORRUPTED;286		}287	}288 289	fa = xfs_attr3_leaf_header_check(bp, dp->i_ino);290	if (fa) {291		__xfs_buf_mark_corrupt(bp, fa);292		goto out_releasebuf;293	}294 295	if (expected_level != 0)296		goto out_corruptbuf;297 298	*pbp = bp;299	return 0;300 301out_corruptbuf:302	xfs_buf_mark_corrupt(bp);303out_releasebuf:304	xfs_trans_brelse(tp, bp);305	xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);306	return -EFSCORRUPTED;307}308 309STATIC int310xfs_attr_node_list(311	struct xfs_attr_list_context	*context)312{313	struct xfs_attrlist_cursor_kern	*cursor = &context->cursor;314	struct xfs_attr3_icleaf_hdr	leafhdr;315	struct xfs_attr_leafblock	*leaf;316	struct xfs_da_intnode		*node;317	struct xfs_buf			*bp;318	struct xfs_inode		*dp = context->dp;319	struct xfs_mount		*mp = dp->i_mount;320	xfs_failaddr_t			fa;321	int				error = 0;322 323	trace_xfs_attr_node_list(context);324 325	cursor->initted = 1;326 327	/*328	 * Do all sorts of validation on the passed-in cursor structure.329	 * If anything is amiss, ignore the cursor and look up the hashval330	 * starting from the btree root.331	 */332	bp = NULL;333	if (cursor->blkno > 0) {334		struct xfs_attr_leaf_entry *entries;335 336		error = xfs_da3_node_read(context->tp, dp, cursor->blkno, &bp,337				XFS_ATTR_FORK);338		if (xfs_metadata_is_sick(error))339			xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);340		if (error != 0 && error != -EFSCORRUPTED)341			return error;342		if (!bp)343			goto need_lookup;344 345		node = bp->b_addr;346		switch (be16_to_cpu(node->hdr.info.magic)) {347		case XFS_DA_NODE_MAGIC:348		case XFS_DA3_NODE_MAGIC:349			trace_xfs_attr_list_wrong_blk(context);350			fa = xfs_da3_node_header_check(bp, dp->i_ino);351			if (fa) {352				__xfs_buf_mark_corrupt(bp, fa);353				xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);354			}355			xfs_trans_brelse(context->tp, bp);356			bp = NULL;357			break;358		case XFS_ATTR_LEAF_MAGIC:359		case XFS_ATTR3_LEAF_MAGIC:360			leaf = bp->b_addr;361			fa = xfs_attr3_leaf_header_check(bp, dp->i_ino);362			if (fa) {363				__xfs_buf_mark_corrupt(bp, fa);364				xfs_trans_brelse(context->tp, bp);365				xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);366				bp = NULL;367				break;368			}369			xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo,370						     &leafhdr, leaf);371			entries = xfs_attr3_leaf_entryp(leaf);372			if (cursor->hashval > be32_to_cpu(373					entries[leafhdr.count - 1].hashval)) {374				trace_xfs_attr_list_wrong_blk(context);375				xfs_trans_brelse(context->tp, bp);376				bp = NULL;377			} else if (cursor->hashval <= be32_to_cpu(378					entries[0].hashval)) {379				trace_xfs_attr_list_wrong_blk(context);380				xfs_trans_brelse(context->tp, bp);381				bp = NULL;382			}383			break;384		default:385			trace_xfs_attr_list_wrong_blk(context);386			xfs_trans_brelse(context->tp, bp);387			bp = NULL;388		}389	}390 391	/*392	 * We did not find what we expected given the cursor's contents,393	 * so we start from the top and work down based on the hash value.394	 * Note that start of node block is same as start of leaf block.395	 */396	if (bp == NULL) {397need_lookup:398		error = xfs_attr_node_list_lookup(context, cursor, &bp);399		if (error || !bp)400			return error;401	}402	ASSERT(bp != NULL);403 404	/*405	 * Roll upward through the blocks, processing each leaf block in406	 * order.  As long as there is space in the result buffer, keep407	 * adding the information.408	 */409	for (;;) {410		leaf = bp->b_addr;411		error = xfs_attr3_leaf_list_int(bp, context);412		if (error)413			break;414		xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);415		if (context->seen_enough || leafhdr.forw == 0)416			break;417		cursor->blkno = leafhdr.forw;418		xfs_trans_brelse(context->tp, bp);419		error = xfs_attr3_leaf_read(context->tp, dp, dp->i_ino,420				cursor->blkno, &bp);421		if (error)422			return error;423	}424	xfs_trans_brelse(context->tp, bp);425	return error;426}427 428/*429 * Copy out attribute list entries for attr_list(), for leaf attribute lists.430 */431int432xfs_attr3_leaf_list_int(433	struct xfs_buf			*bp,434	struct xfs_attr_list_context	*context)435{436	struct xfs_attrlist_cursor_kern	*cursor = &context->cursor;437	struct xfs_attr_leafblock	*leaf;438	struct xfs_attr3_icleaf_hdr	ichdr;439	struct xfs_attr_leaf_entry	*entries;440	struct xfs_attr_leaf_entry	*entry;441	int				i;442	struct xfs_mount		*mp = context->dp->i_mount;443 444	trace_xfs_attr_list_leaf(context);445 446	leaf = bp->b_addr;447	xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf);448	entries = xfs_attr3_leaf_entryp(leaf);449 450	cursor->initted = 1;451 452	/*453	 * Re-find our place in the leaf block if this is a new syscall.454	 */455	if (context->resynch) {456		entry = &entries[0];457		for (i = 0; i < ichdr.count; entry++, i++) {458			if (be32_to_cpu(entry->hashval) == cursor->hashval) {459				if (cursor->offset == context->dupcnt) {460					context->dupcnt = 0;461					break;462				}463				context->dupcnt++;464			} else if (be32_to_cpu(entry->hashval) >465					cursor->hashval) {466				context->dupcnt = 0;467				break;468			}469		}470		if (i == ichdr.count) {471			trace_xfs_attr_list_notfound(context);472			return 0;473		}474	} else {475		entry = &entries[0];476		i = 0;477	}478	context->resynch = 0;479 480	/*481	 * We have found our place, start copying out the new attributes.482	 */483	for (; i < ichdr.count; entry++, i++) {484		char *name;485		void *value;486		int namelen, valuelen;487 488		if (be32_to_cpu(entry->hashval) != cursor->hashval) {489			cursor->hashval = be32_to_cpu(entry->hashval);490			cursor->offset = 0;491		}492 493		if ((entry->flags & XFS_ATTR_INCOMPLETE) &&494		    !context->allow_incomplete)495			continue;496 497		if (entry->flags & XFS_ATTR_LOCAL) {498			xfs_attr_leaf_name_local_t *name_loc;499 500			name_loc = xfs_attr3_leaf_name_local(leaf, i);501			name = name_loc->nameval;502			namelen = name_loc->namelen;503			value = &name_loc->nameval[name_loc->namelen];504			valuelen = be16_to_cpu(name_loc->valuelen);505		} else {506			xfs_attr_leaf_name_remote_t *name_rmt;507 508			name_rmt = xfs_attr3_leaf_name_remote(leaf, i);509			name = name_rmt->name;510			namelen = name_rmt->namelen;511			value = NULL;512			valuelen = be32_to_cpu(name_rmt->valuelen);513		}514 515		if (XFS_IS_CORRUPT(context->dp->i_mount,516				   !xfs_attr_namecheck(entry->flags, name,517						       namelen))) {518			xfs_dirattr_mark_sick(context->dp, XFS_ATTR_FORK);519			return -EFSCORRUPTED;520		}521		context->put_listent(context, entry->flags,522					      name, namelen, value, valuelen);523		if (context->seen_enough)524			break;525		cursor->offset++;526	}527	trace_xfs_attr_list_leaf_end(context);528	return 0;529}530 531/*532 * Copy out attribute entries for attr_list(), for leaf attribute lists.533 */534STATIC int535xfs_attr_leaf_list(536	struct xfs_attr_list_context	*context)537{538	struct xfs_buf			*bp;539	int				error;540 541	trace_xfs_attr_leaf_list(context);542 543	context->cursor.blkno = 0;544	error = xfs_attr3_leaf_read(context->tp, context->dp,545			context->dp->i_ino, 0, &bp);546	if (error)547		return error;548 549	error = xfs_attr3_leaf_list_int(bp, context);550	xfs_trans_brelse(context->tp, bp);551	return error;552}553 554int555xfs_attr_list_ilocked(556	struct xfs_attr_list_context	*context)557{558	struct xfs_inode		*dp = context->dp;559	int				error;560 561	xfs_assert_ilocked(dp, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL);562 563	/*564	 * Decide on what work routines to call based on the inode size.565	 */566	if (!xfs_inode_hasattr(dp))567		return 0;568	if (dp->i_af.if_format == XFS_DINODE_FMT_LOCAL)569		return xfs_attr_shortform_list(context);570 571	/* Prerequisite for xfs_attr_is_leaf */572	error = xfs_iread_extents(NULL, dp, XFS_ATTR_FORK);573	if (error)574		return error;575 576	if (xfs_attr_is_leaf(dp))577		return xfs_attr_leaf_list(context);578	return xfs_attr_node_list(context);579}580 581int582xfs_attr_list(583	struct xfs_attr_list_context	*context)584{585	struct xfs_inode		*dp = context->dp;586	uint				lock_mode;587	int				error;588 589	XFS_STATS_INC(dp->i_mount, xs_attr_list);590 591	if (xfs_is_shutdown(dp->i_mount))592		return -EIO;593 594	lock_mode = xfs_ilock_attr_map_shared(dp);595	error = xfs_attr_list_ilocked(context);596	xfs_iunlock(dp, lock_mode);597	return error;598}599