diff options
Diffstat (limited to 'fs/xfs/scrub/listxattr.c')
-rw-r--r-- | fs/xfs/scrub/listxattr.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/fs/xfs/scrub/listxattr.c b/fs/xfs/scrub/listxattr.c new file mode 100644 index 000000000000..256ff7700c94 --- /dev/null +++ b/fs/xfs/scrub/listxattr.c @@ -0,0 +1,320 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022-2024 Oracle. All Rights Reserved. + * Author: Darrick J. Wong <djwong@kernel.org> + */ +#include "xfs.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_log_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_attr.h" +#include "xfs_attr_leaf.h" +#include "xfs_attr_sf.h" +#include "xfs_trans.h" +#include "scrub/scrub.h" +#include "scrub/bitmap.h" +#include "scrub/dab_bitmap.h" +#include "scrub/listxattr.h" + +/* Call a function for every entry in a shortform xattr structure. */ +STATIC int +xchk_xattr_walk_sf( + struct xfs_scrub *sc, + struct xfs_inode *ip, + xchk_xattr_fn attr_fn, + void *priv) +{ + struct xfs_attr_sf_hdr *hdr = ip->i_af.if_data; + struct xfs_attr_sf_entry *sfe; + unsigned int i; + int error; + + sfe = xfs_attr_sf_firstentry(hdr); + for (i = 0; i < hdr->count; i++) { + error = attr_fn(sc, ip, sfe->flags, sfe->nameval, sfe->namelen, + &sfe->nameval[sfe->namelen], sfe->valuelen, + priv); + if (error) + return error; + + sfe = xfs_attr_sf_nextentry(sfe); + } + + return 0; +} + +/* Call a function for every entry in this xattr leaf block. */ +STATIC int +xchk_xattr_walk_leaf_entries( + struct xfs_scrub *sc, + struct xfs_inode *ip, + xchk_xattr_fn attr_fn, + struct xfs_buf *bp, + void *priv) +{ + struct xfs_attr3_icleaf_hdr ichdr; + struct xfs_mount *mp = sc->mp; + struct xfs_attr_leafblock *leaf = bp->b_addr; + struct xfs_attr_leaf_entry *entry; + unsigned int i; + int error; + + xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &ichdr, leaf); + entry = xfs_attr3_leaf_entryp(leaf); + + for (i = 0; i < ichdr.count; entry++, i++) { + void *value; + unsigned char *name; + unsigned int namelen, valuelen; + + if (entry->flags & XFS_ATTR_LOCAL) { + struct xfs_attr_leaf_name_local *name_loc; + + name_loc = xfs_attr3_leaf_name_local(leaf, i); + name = name_loc->nameval; + namelen = name_loc->namelen; + value = &name_loc->nameval[name_loc->namelen]; + valuelen = be16_to_cpu(name_loc->valuelen); + } else { + struct xfs_attr_leaf_name_remote *name_rmt; + + name_rmt = xfs_attr3_leaf_name_remote(leaf, i); + name = name_rmt->name; + namelen = name_rmt->namelen; + value = NULL; + valuelen = be32_to_cpu(name_rmt->valuelen); + } + + error = attr_fn(sc, ip, entry->flags, name, namelen, value, + valuelen, priv); + if (error) + return error; + + } + + return 0; +} + +/* + * Call a function for every entry in a leaf-format xattr structure. Avoid + * memory allocations for the loop detector since there's only one block. + */ +STATIC int +xchk_xattr_walk_leaf( + struct xfs_scrub *sc, + struct xfs_inode *ip, + xchk_xattr_fn attr_fn, + void *priv) +{ + struct xfs_buf *leaf_bp; + int error; + + error = xfs_attr3_leaf_read(sc->tp, ip, ip->i_ino, 0, &leaf_bp); + if (error) + return error; + + error = xchk_xattr_walk_leaf_entries(sc, ip, attr_fn, leaf_bp, priv); + xfs_trans_brelse(sc->tp, leaf_bp); + return error; +} + +/* Find the leftmost leaf in the xattr dabtree. */ +STATIC int +xchk_xattr_find_leftmost_leaf( + struct xfs_scrub *sc, + struct xfs_inode *ip, + struct xdab_bitmap *seen_dablks, + struct xfs_buf **leaf_bpp) +{ + struct xfs_da3_icnode_hdr nodehdr; + struct xfs_mount *mp = sc->mp; + struct xfs_trans *tp = sc->tp; + struct xfs_da_intnode *node; + struct xfs_da_node_entry *btree; + struct xfs_buf *bp; + xfs_failaddr_t fa; + xfs_dablk_t blkno = 0; + unsigned int expected_level = 0; + int error; + + for (;;) { + xfs_extlen_t len = 1; + uint16_t magic; + + /* Make sure we haven't seen this new block already. */ + if (xdab_bitmap_test(seen_dablks, blkno, &len)) + return -EFSCORRUPTED; + + error = xfs_da3_node_read(tp, ip, blkno, &bp, XFS_ATTR_FORK); + if (error) + return error; + + node = bp->b_addr; + magic = be16_to_cpu(node->hdr.info.magic); + if (magic == XFS_ATTR_LEAF_MAGIC || + magic == XFS_ATTR3_LEAF_MAGIC) + break; + + error = -EFSCORRUPTED; + if (magic != XFS_DA_NODE_MAGIC && + magic != XFS_DA3_NODE_MAGIC) + goto out_buf; + + fa = xfs_da3_node_header_check(bp, ip->i_ino); + if (fa) + goto out_buf; + + xfs_da3_node_hdr_from_disk(mp, &nodehdr, node); + + if (nodehdr.count == 0 || nodehdr.level >= XFS_DA_NODE_MAXDEPTH) + goto out_buf; + + /* Check the level from the root node. */ + if (blkno == 0) + expected_level = nodehdr.level - 1; + else if (expected_level != nodehdr.level) + goto out_buf; + else + expected_level--; + + /* Remember that we've seen this node. */ + error = xdab_bitmap_set(seen_dablks, blkno, 1); + if (error) + goto out_buf; + + /* Find the next level towards the leaves of the dabtree. */ + btree = nodehdr.btree; + blkno = be32_to_cpu(btree->before); + xfs_trans_brelse(tp, bp); + } + + error = -EFSCORRUPTED; + fa = xfs_attr3_leaf_header_check(bp, ip->i_ino); + if (fa) + goto out_buf; + + if (expected_level != 0) + goto out_buf; + + /* Remember that we've seen this leaf. */ + error = xdab_bitmap_set(seen_dablks, blkno, 1); + if (error) + goto out_buf; + + *leaf_bpp = bp; + return 0; + +out_buf: + xfs_trans_brelse(tp, bp); + return error; +} + +/* Call a function for every entry in a node-format xattr structure. */ +STATIC int +xchk_xattr_walk_node( + struct xfs_scrub *sc, + struct xfs_inode *ip, + xchk_xattr_fn attr_fn, + xchk_xattrleaf_fn leaf_fn, + void *priv) +{ + struct xfs_attr3_icleaf_hdr leafhdr; + struct xdab_bitmap seen_dablks; + struct xfs_mount *mp = sc->mp; + struct xfs_attr_leafblock *leaf; + struct xfs_buf *leaf_bp; + int error; + + xdab_bitmap_init(&seen_dablks); + + error = xchk_xattr_find_leftmost_leaf(sc, ip, &seen_dablks, &leaf_bp); + if (error) + goto out_bitmap; + + for (;;) { + xfs_extlen_t len; + + error = xchk_xattr_walk_leaf_entries(sc, ip, attr_fn, leaf_bp, + priv); + if (error) + goto out_leaf; + + /* Find the right sibling of this leaf block. */ + leaf = leaf_bp->b_addr; + xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf); + if (leafhdr.forw == 0) + goto out_leaf; + + xfs_trans_brelse(sc->tp, leaf_bp); + + if (leaf_fn) { + error = leaf_fn(sc, priv); + if (error) + goto out_bitmap; + } + + /* Make sure we haven't seen this new leaf already. */ + len = 1; + if (xdab_bitmap_test(&seen_dablks, leafhdr.forw, &len)) { + error = -EFSCORRUPTED; + goto out_bitmap; + } + + error = xfs_attr3_leaf_read(sc->tp, ip, ip->i_ino, + leafhdr.forw, &leaf_bp); + if (error) + goto out_bitmap; + + /* Remember that we've seen this new leaf. */ + error = xdab_bitmap_set(&seen_dablks, leafhdr.forw, 1); + if (error) + goto out_leaf; + } + +out_leaf: + xfs_trans_brelse(sc->tp, leaf_bp); +out_bitmap: + xdab_bitmap_destroy(&seen_dablks); + return error; +} + +/* + * Call a function for every extended attribute in a file. + * + * Callers must hold the ILOCK. No validation or cursor restarts allowed. + * Returns -EFSCORRUPTED on any problem, including loops in the dabtree. + */ +int +xchk_xattr_walk( + struct xfs_scrub *sc, + struct xfs_inode *ip, + xchk_xattr_fn attr_fn, + xchk_xattrleaf_fn leaf_fn, + void *priv) +{ + int error; + + xfs_assert_ilocked(ip, XFS_ILOCK_SHARED | XFS_ILOCK_EXCL); + + if (!xfs_inode_hasattr(ip)) + return 0; + + if (ip->i_af.if_format == XFS_DINODE_FMT_LOCAL) + return xchk_xattr_walk_sf(sc, ip, attr_fn, priv); + + /* attr functions require that the attr fork is loaded */ + error = xfs_iread_extents(sc->tp, ip, XFS_ATTR_FORK); + if (error) + return error; + + if (xfs_attr_is_leaf(ip)) + return xchk_xattr_walk_leaf(sc, ip, attr_fn, priv); + + return xchk_xattr_walk_node(sc, ip, attr_fn, leaf_fn, priv); +} |