From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Scrub the hash tree, keys, and values in an extended attribute structure. Refactor the attribute code to use the transaction if the caller supplied one to avoid buffer deadocks. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/xfs/Makefile | 1 fs/xfs/libxfs/xfs_fs.h | 3 - fs/xfs/scrub/attr.c | 218 ++++++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/scrub/common.h | 2 fs/xfs/scrub/scrub.c | 8 ++ fs/xfs/scrub/scrub.h | 2 6 files changed, 233 insertions(+), 1 deletion(-) create mode 100644 fs/xfs/scrub/attr.c diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index 69aa88e..4d46399 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -148,6 +148,7 @@ xfs-y += $(addprefix scrub/, \ trace.o \ agheader.o \ alloc.o \ + attr.o \ bmap.o \ btree.o \ common.o \ diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h index b16d004..0834ce6 100644 --- a/fs/xfs/libxfs/xfs_fs.h +++ b/fs/xfs/libxfs/xfs_fs.h @@ -499,9 +499,10 @@ struct xfs_scrub_metadata { #define XFS_SCRUB_TYPE_BMBTA 13 /* attr fork block mapping */ #define XFS_SCRUB_TYPE_BMBTC 14 /* CoW fork block mapping */ #define XFS_SCRUB_TYPE_DIR 15 /* directory */ +#define XFS_SCRUB_TYPE_XATTR 16 /* extended attribute */ /* Number of scrub subcommands. */ -#define XFS_SCRUB_TYPE_NR 16 +#define XFS_SCRUB_TYPE_NR 17 /* i: Repair this metadata. */ #define XFS_SCRUB_IFLAG_REPAIR (1 << 0) diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c new file mode 100644 index 0000000..319c42b --- /dev/null +++ b/fs/xfs/scrub/attr.c @@ -0,0 +1,218 @@ +/* + * Copyright (C) 2017 Oracle. All Rights Reserved. + * + * Author: Darrick J. Wong <darrick.wong@xxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#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_defer.h" +#include "xfs_btree.h" +#include "xfs_bit.h" +#include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_sb.h" +#include "xfs_inode.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_dir2.h" +#include "xfs_attr.h" +#include "xfs_attr_leaf.h" +#include "scrub/xfs_scrub.h" +#include "scrub/scrub.h" +#include "scrub/common.h" +#include "scrub/dabtree.h" +#include "scrub/trace.h" + +#include <linux/posix_acl_xattr.h> +#include <linux/xattr.h> + +/* Set us up to scrub an inode's extended attributes. */ +int +xfs_scrub_setup_xattr( + struct xfs_scrub_context *sc, + struct xfs_inode *ip) +{ + /* Allocate the buffer without the inode lock held. */ + sc->buf = kmem_zalloc_large(XATTR_SIZE_MAX, KM_SLEEP); + if (!sc->buf) + return -ENOMEM; + + return xfs_scrub_setup_inode_contents(sc, ip, 0); +} + +/* Extended Attributes */ + +struct xfs_scrub_xattr { + struct xfs_attr_list_context context; + struct xfs_scrub_context *sc; +}; + +/* Check that an extended attribute key can be looked up by hash. */ +static void +xfs_scrub_xattr_listent( + struct xfs_attr_list_context *context, + int flags, + unsigned char *name, + int namelen, + int valuelen) +{ + struct xfs_scrub_xattr *sx; + struct xfs_da_args args = {0}; + int error = 0; + + sx = container_of(context, struct xfs_scrub_xattr, context); + + args.flags = ATTR_KERNOTIME; + if (flags & XFS_ATTR_ROOT) + args.flags |= ATTR_ROOT; + else if (flags & XFS_ATTR_SECURE) + args.flags |= ATTR_SECURE; + args.geo = context->dp->i_mount->m_attr_geo; + args.whichfork = XFS_ATTR_FORK; + args.dp = context->dp; + args.name = name; + args.namelen = namelen; + args.hashval = xfs_da_hashname(args.name, args.namelen); + args.trans = context->tp; + args.value = sx->sc->buf; + args.valuelen = XATTR_SIZE_MAX; + + error = xfs_attr_get_ilocked(context->dp, &args); + if (error == -EEXIST) + error = 0; + if (!xfs_scrub_fblock_op_ok(sx->sc, XFS_ATTR_FORK, args.blkno, &error)) + goto fail_xref; + if (args.valuelen != valuelen) + xfs_scrub_fblock_set_corrupt(sx->sc, XFS_ATTR_FORK, + args.blkno); + +fail_xref: + return; +} + +/* Scrub a attribute btree record. */ +STATIC int +xfs_scrub_xattr_rec( + struct xfs_scrub_da_btree *ds, + int level, + void *rec) +{ + struct xfs_mount *mp = ds->state->mp; + struct xfs_attr_leaf_entry *ent = rec; + struct xfs_da_state_blk *blk; + struct xfs_attr_leaf_name_local *lentry; + struct xfs_attr_leaf_name_remote *rentry; + struct xfs_buf *bp; + xfs_dahash_t calc_hash; + xfs_dahash_t hash; + int nameidx; + int hdrsize; + unsigned int badflags; + int error; + + blk = &ds->state->path.blk[level]; + + /* Check the hash of the entry. */ + error = xfs_scrub_da_btree_hash(ds, level, &ent->hashval); + if (error) + goto out; + + /* Find the attr entry's location. */ + bp = blk->bp; + hdrsize = xfs_attr3_leaf_hdr_size(bp->b_addr); + nameidx = be16_to_cpu(ent->nameidx); + if (nameidx < hdrsize || nameidx >= mp->m_attr_geo->blksize) { + xfs_scrub_da_set_corrupt(ds, level); + goto out; + } + + /* Retrieve the entry and check it. */ + hash = be32_to_cpu(ent->hashval); + badflags = ~(XFS_ATTR_LOCAL | XFS_ATTR_ROOT | XFS_ATTR_SECURE | + XFS_ATTR_INCOMPLETE); + if ((ent->flags & badflags) != 0) + xfs_scrub_da_set_corrupt(ds, level); + if (ent->flags & XFS_ATTR_LOCAL) { + lentry = (struct xfs_attr_leaf_name_local *) + (((char *)bp->b_addr) + nameidx); + if (lentry->namelen <= 0) { + xfs_scrub_da_set_corrupt(ds, level); + goto out; + } + calc_hash = xfs_da_hashname(lentry->nameval, lentry->namelen); + } else { + rentry = (struct xfs_attr_leaf_name_remote *) + (((char *)bp->b_addr) + nameidx); + if (rentry->namelen <= 0) { + xfs_scrub_da_set_corrupt(ds, level); + goto out; + } + calc_hash = xfs_da_hashname(rentry->name, rentry->namelen); + } + if (calc_hash != hash) + xfs_scrub_da_set_corrupt(ds, level); + +out: + return error; +} + +/* Scrub the extended attribute metadata. */ +int +xfs_scrub_xattr( + struct xfs_scrub_context *sc) +{ + struct xfs_scrub_xattr sx = { 0 }; + struct attrlist_cursor_kern cursor = { 0 }; + int error = 0; + + if (!xfs_inode_hasattr(sc->ip)) + return -ENOENT; + + memset(&sx, 0, sizeof(sx)); + /* Check attribute tree structure */ + error = xfs_scrub_da_btree(sc, XFS_ATTR_FORK, xfs_scrub_xattr_rec); + if (error) + goto out; + + /* Check that every attr key can also be looked up by hash. */ + sx.context.dp = sc->ip; + sx.context.cursor = &cursor; + sx.context.resynch = 1; + sx.context.put_listent = xfs_scrub_xattr_listent; + sx.context.tp = sc->tp; + sx.sc = sc; + + /* + * Look up every xattr in this file by name. + * + * The VFS only locks i_rwsem when modifying attrs, so keep all + * three locks held because that's the only way to ensure we're + * the only thread poking into the da btree. We traverse the da + * btree while holding a leaf buffer locked for the xattr name + * iteration, which doesn't really follow the usual buffer + * locking order. + */ + error = xfs_attr_list_int_ilocked(&sx.context); + if (!xfs_scrub_fblock_op_ok(sc, XFS_ATTR_FORK, 0, &error)) + goto out; +out: + return error; +} diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h index f530301..b2d3bc7 100644 --- a/fs/xfs/scrub/common.h +++ b/fs/xfs/scrub/common.h @@ -96,6 +96,8 @@ int xfs_scrub_setup_inode_bmap_data(struct xfs_scrub_context *sc, struct xfs_inode *ip); int xfs_scrub_setup_directory(struct xfs_scrub_context *sc, struct xfs_inode *ip); +int xfs_scrub_setup_xattr(struct xfs_scrub_context *sc, + struct xfs_inode *ip); void xfs_scrub_ag_free(struct xfs_scrub_context *sc, struct xfs_scrub_ag *sa); int xfs_scrub_ag_init(struct xfs_scrub_context *sc, xfs_agnumber_t agno, diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c index f3a84d9..d1b80dc 100644 --- a/fs/xfs/scrub/scrub.c +++ b/fs/xfs/scrub/scrub.c @@ -152,6 +152,10 @@ xfs_scrub_teardown( iput(VFS_I(sc->ip)); sc->ip = NULL; } + if (sc->buf) { + kmem_free(sc->buf); + sc->buf = NULL; + } return error; } @@ -225,6 +229,10 @@ static const struct xfs_scrub_meta_ops meta_scrub_ops[] = { .setup = xfs_scrub_setup_directory, .scrub = xfs_scrub_directory, }, + { /* extended attributes */ + .setup = xfs_scrub_setup_xattr, + .scrub = xfs_scrub_xattr, + }, }; /* This isn't a stable feature, warn once per day. */ diff --git a/fs/xfs/scrub/scrub.h b/fs/xfs/scrub/scrub.h index 844506e..d31ff58 100644 --- a/fs/xfs/scrub/scrub.h +++ b/fs/xfs/scrub/scrub.h @@ -59,6 +59,7 @@ struct xfs_scrub_context { const struct xfs_scrub_meta_ops *ops; struct xfs_trans *tp; struct xfs_inode *ip; + void *buf; uint ilock_flags; bool try_harder; @@ -83,5 +84,6 @@ int xfs_scrub_bmap_data(struct xfs_scrub_context *sc); int xfs_scrub_bmap_attr(struct xfs_scrub_context *sc); int xfs_scrub_bmap_cow(struct xfs_scrub_context *sc); int xfs_scrub_directory(struct xfs_scrub_context *sc); +int xfs_scrub_xattr(struct xfs_scrub_context *sc); #endif /* __XFS_SCRUB_SCRUB_H__ */ -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html