[PATCH 3/6] xfs: repair extended attributes

Darrick J. Wong
2023-12-31T20:35:43Z

If the extended attributes look bad, try to sift through the rubble to
find whatever keys/values we can, stage a new attribute structure in a
temporary file and use the atomic extent swapping mechanism to commit
the results in bulk.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/Makefile | 1
fs/xfs/libxfs/xfs_attr.c | 2
fs/xfs/libxfs/xfs_attr.h | 2
fs/xfs/libxfs/xfs_da_format.h | 5
fs/xfs/scrub/attr.c | 20 +
fs/xfs/scrub/attr.h | 7
fs/xfs/scrub/attr_repair.c | 1203 +++++++++++++++++++++++++++++++++++++++++
fs/xfs/scrub/attr_repair.h | 11
fs/xfs/scrub/repair.c | 46 ++
fs/xfs/scrub/repair.h | 6
fs/xfs/scrub/scrub.c | 2
fs/xfs/scrub/trace.h | 83 +++
fs/xfs/scrub/xfarray.c | 17 +
fs/xfs/scrub/xfarray.h | 2
fs/xfs/scrub/xfblob.c | 17 +
fs/xfs/scrub/xfblob.h | 2
fs/xfs/scrub/xfile.h | 12
fs/xfs/xfs_buf.c | 3
fs/xfs/xfs_trace.h | 2
19 files changed, 1439 insertions(+), 4 deletions(-)
create mode 100644 fs/xfs/scrub/attr_repair.c
create mode 100644 fs/xfs/scrub/attr_repair.h

diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index 72df9890edcf6..9b227be3e28b6 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -194,6 +194,7 @@ ifeq ($(CONFIG_XFS_ONLINE_REPAIR),y)
xfs-y += $(addprefix scrub/, \
agheader_repair.o \
alloc_repair.o \
+ attr_repair.o \
bmap_repair.o \
cow_repair.o \
fscounters_repair.o \
diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 1e94e933d7682..b002ddd5f05a2 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -1047,7 +1047,7 @@ xfs_attr_set(
* External routines when attribute list is inside the inode
*========================================================================*/

-static inline int xfs_attr_sf_totsize(struct xfs_inode *dp)
+int xfs_attr_sf_totsize(struct xfs_inode *dp)
{
struct xfs_attr_shortform *sf;

diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index 81be9b3e40047..e4f55008552b4 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -618,4 +618,6 @@ extern struct kmem_cache *xfs_attr_intent_cache;
int __init xfs_attr_intent_init_cache(void);
void xfs_attr_intent_destroy_cache(void);

+int xfs_attr_sf_totsize(struct xfs_inode *dp);
+
#endif /* __XFS_ATTR_H__ */
diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h
index 44748f1640e53..0e1ada44f21ba 100644
--- a/fs/xfs/libxfs/xfs_da_format.h
+++ b/fs/xfs/libxfs/xfs_da_format.h
@@ -716,6 +716,11 @@ struct xfs_attr3_leafblock {
#define XFS_ATTR_INCOMPLETE (1u << XFS_ATTR_INCOMPLETE_BIT)
#define XFS_ATTR_NSP_ONDISK_MASK (XFS_ATTR_ROOT | XFS_ATTR_SECURE)

+#define XFS_ATTR_NAMESPACE_STR \
+ { XFS_ATTR_LOCAL, "local" }, \
+ { XFS_ATTR_ROOT, "root" }, \
+ { XFS_ATTR_SECURE, "secure" }
+
/*
* Alignment for namelist and valuelist entries (since they are mixed
* there can be only one alignment value)
diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c
index 40a59b24c209f..692e1b2837bbb 100644
--- a/fs/xfs/scrub/attr.c
+++ b/fs/xfs/scrub/attr.c
@@ -10,6 +10,7 @@
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_log_format.h"
+#include "xfs_trans.h"
#include "xfs_inode.h"
#include "xfs_da_format.h"
#include "xfs_da_btree.h"
@@ -20,6 +21,7 @@
#include "scrub/common.h"
#include "scrub/dabtree.h"
#include "scrub/attr.h"
+#include "scrub/repair.h"

/* Free the buffers linked from the xattr buffer. */
static void
@@ -35,6 +37,8 @@ xchk_xattr_buf_cleanup(
kvfree(ab->value);
ab->value = NULL;
ab->value_sz = 0;
+ kvfree(ab->name);
+ ab->name = NULL;
}

/*
@@ -65,7 +69,7 @@ xchk_xattr_want_freemap(
* reallocating the buffer if necessary. Buffer contents are not preserved
* across a reallocation.
*/
-static int
+int
xchk_setup_xattr_buf(
struct xfs_scrub *sc,
size_t value_size)
@@ -95,6 +99,12 @@ xchk_setup_xattr_buf(
return -ENOMEM;
}

+ if (xchk_could_repair(sc)) {
+ ab->name = kvmalloc(XATTR_NAME_MAX + 1, XCHK_GFP_FLAGS);
+ if (!ab->name)
+ return -ENOMEM;
+ }
+
resize_value:
if (ab->value_sz >= value_size)
return 0;
@@ -121,6 +131,12 @@ xchk_setup_xattr(
{
int error;

+ if (xchk_could_repair(sc)) {
+ error = xrep_setup_xattr(sc);
+ if (error)
+ return error;
+ }
+
/*
* We failed to get memory while checking attrs, so this time try to
* get all the memory we're ever going to need. Allocate the buffer
@@ -247,7 +263,7 @@ xchk_xattr_listent(
* Within a char, the lowest bit of the char represents the byte with
* the smallest address
*/
-STATIC bool
+bool
xchk_xattr_set_map(
struct xfs_scrub *sc,
unsigned long *map,
diff --git a/fs/xfs/scrub/attr.h b/fs/xfs/scrub/attr.h
index 48fd9402c4328..7db58af56646b 100644
--- a/fs/xfs/scrub/attr.h
+++ b/fs/xfs/scrub/attr.h
@@ -16,9 +16,16 @@ struct xchk_xattr_buf {
/* Bitmap of free space in xattr leaf blocks. */
unsigned long *freemap;

+ /* Memory buffer used to hold salvaged xattr names. */
+ unsigned char *name;
+
/* Memory buffer used to extract xattr values. */
void *value;
size_t value_sz;
};

+bool xchk_xattr_set_map(struct xfs_scrub *sc, unsigned long *map,
+ unsigned int start, unsigned int len);
+int xchk_setup_xattr_buf(struct xfs_scrub *sc, size_t value_size);
+
#endif /* __XFS_SCRUB_ATTR_H__ */
diff --git a/fs/xfs/scrub/attr_repair.c b/fs/xfs/scrub/attr_repair.c
new file mode 100644
index 0000000000000..9a88d46392626
--- /dev/null
+++ b/fs/xfs/scrub/attr_repair.c
@@ -0,0 +1,1203 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2018-2024 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_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 "xfs_attr_sf.h"
+#include "xfs_attr_remote.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_util.h"
+#include "xfs_swapext.h"
+#include "xfs_xchgrange.h"
+#include "xfs_acl.h"
+#include "scrub/xfs_scrub.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/trace.h"
+#include "scrub/repair.h"
+#include "scrub/tempfile.h"
+#include "scrub/tempswap.h"
+#include "scrub/xfile.h"
+#include "scrub/xfarray.h"
+#include "scrub/xfblob.h"
+#include "scrub/attr.h"
+#include "scrub/reap.h"
+#include "scrub/attr_repair.h"
+
+/*
+ * Extended Attribute Repair
+ * =========================
+ *
+ * We repair extended attributes by reading the attr leaf blocks looking for
+ * attributes entries that look salvageable (name passes verifiers, value can
+ * be retrieved, etc). Each extended attribute worth salvaging is stashed in
+ * memory, and the stashed entries are periodically replayed into a temporary
+ * file to constrain memory use. Batching the construction of the temporary
+ * extended attribute structure in this fashion reduces lock cycling of the
+ * file being repaired and the temporary file.
+ *
+ * When salvaging completes, the remaining stashed attributes are replayed to
+ * the temporary file. An atomic extent swap is used to commit the new xattr
+ * blocks to the file being repaired. This will disrupt attrmulti cursors.
+ */
+
+struct xrep_xattr_key {
+ /* Cookie for retrieval of the xattr name. */
+ xfblob_cookie name_cookie;
+
+ /* Cookie for retrieval of the xattr value. */
+ xfblob_cookie value_cookie;
+
+ /* XFS_ATTR_* flags */
+ int flags;
+
+ /* Length of the value and name. */
+ uint32_t valuelen;
+ uint16_t namelen;
+};
+
+/*
+ * Stash up to 8 pages of attrs in xattr_records/xattr_blobs before we write
+ * them to the temp file.
+ */
+#define XREP_XATTR_MAX_STASH_BYTES (PAGE_SIZE * 8)
+
+struct xrep_xattr {
+ struct xfs_scrub *sc;
+
+ /* Information for swapping attr forks at the end. */
+ struct xrep_tempswap tx;
+
+ /* xattr keys */
+ struct xfarray *xattr_records;
+
+ /* xattr values */
+ struct xfblob *xattr_blobs;
+
+ /* Number of attributes that we are salvaging. */
+ unsigned long long attrs_found;
+};
+
+/* Set up to recreate the extended attributes. */
+int
+xrep_setup_xattr(
+ struct xfs_scrub *sc)
+{
+ return xrep_tempfile_create(sc, S_IFREG);
+}
+
+/*
+ * Decide if we want to salvage this attribute. We don't bother with
+ * incomplete or oversized keys or values. The @value parameter can be null
+ * for remote attrs.
+ */
+STATIC int
+xrep_xattr_want_salvage(
+ struct xrep_xattr *rx,
+ unsigned int attr_flags,
+ const void *name,
+ int namelen,
+ const void *value,
+ int valuelen)
+{
+ if (attr_flags & XFS_ATTR_INCOMPLETE)
+ return false;
+ if (namelen > XATTR_NAME_MAX || namelen <= 0)
+ return false;
+ if (valuelen > XATTR_SIZE_MAX || valuelen < 0)
+ return false;
+ return true;
+}
+
+/* Allocate an in-core record to hold xattrs while we rebuild the xattr data. */
+STATIC int
+xrep_xattr_salvage_key(
+ struct xrep_xattr *rx,
+ int flags,
+ unsigned char *name,
+ int namelen,
+ unsigned char *value,
+ int valuelen)
+{
+ struct xrep_xattr_key key = {
+ .valuelen = valuelen,
+ .flags = flags & XFS_ATTR_NSP_ONDISK_MASK,
+ };
+ unsigned int i = 0;
+ int error = 0;
+
+ if (xchk_should_terminate(rx->sc, &error))
+ return error;
+
+ /*
+ * Truncate the name to the first character that would trip namecheck.
+ * If we no longer have a name after that, ignore this attribute.
+ */
+ while (i < namelen && name[i] != 0)
+ i++;
+ if (i == 0)
+ return 0;
+ key.namelen = i;
+
+ trace_xrep_xattr_salvage_rec(rx->sc->ip, flags, name, key.namelen,
+ valuelen);
+
+ error = xfblob_store(rx->xattr_blobs, &key.name_cookie, name,
+ key.namelen);
+ if (error)
+ return error;
+
+ error = xfblob_store(rx->xattr_blobs, &key.value_cookie, value,
+ key.valuelen);
+ if (error)
+ return error;
+
+ error = xfarray_append(rx->xattr_records, &key);
+ if (error)
+ return error;
+
+ rx->attrs_found++;
+ return 0;
+}
+
+/*
+ * Record a shortform extended attribute key & value for later reinsertion
+ * into the inode.
+ */
+STATIC int
+xrep_xattr_salvage_sf_attr(
+ struct xrep_xattr *rx,
+ struct xfs_attr_shortform *sf,
+ struct xfs_attr_sf_entry *sfe)
+{
+ struct xfs_scrub *sc = rx->sc;
+ struct xchk_xattr_buf *ab = sc->buf;
+ unsigned char *name = sfe->nameval;
+ unsigned char *value = &sfe->nameval[sfe->namelen];
+
+ if (!xchk_xattr_set_map(sc, ab->usedmap, (char *)name - (char *)sf,
+ sfe->namelen))
+ return 0;
+
+ if (!xchk_xattr_set_map(sc, ab->usedmap, (char *)value - (char *)sf,
+ sfe->valuelen))
+ return 0;
+
+ if (!xrep_xattr_want_salvage(rx, sfe->flags, sfe->nameval,
+ sfe->namelen, value, sfe->valuelen))
+ return 0;
+
+ return xrep_xattr_salvage_key(rx, sfe->flags, sfe->nameval,
+ sfe->namelen, value, sfe->valuelen);
+}
+
+/*
+ * Record a local format extended attribute key & value for later reinsertion
+ * into the inode.
+ */
+STATIC int
+xrep_xattr_salvage_local_attr(
+ struct xrep_xattr *rx,
+ struct xfs_attr_leaf_entry *ent,
+ unsigned int nameidx,
+ const char *buf_end,
+ struct xfs_attr_leaf_name_local *lentry)
+{
+ struct xchk_xattr_buf *ab = rx->sc->buf;
+ unsigned char *value;
+ unsigned int valuelen;
+ unsigned int namesize;
+
+ /*
+ * Decode the leaf local entry format. If something seems wrong, we
+ * junk the attribute.
+ */
+ value = &lentry->nameval[lentry->namelen];
+ valuelen = be16_to_cpu(lentry->valuelen);
+ namesize = xfs_attr_leaf_entsize_local(lentry->namelen, valuelen);
+ if ((char *)lentry + namesize > buf_end)
+ return 0;
+ if (!xrep_xattr_want_salvage(rx, ent->flags, lentry->nameval,
+ lentry->namelen, value, valuelen))
+ return 0;
+ if (!xchk_xattr_set_map(rx->sc, ab->usedmap, nameidx, namesize))
+ return 0;
+
+ /* Try to save this attribute. */
+ return xrep_xattr_salvage_key(rx, ent->flags, lentry->nameval,
+ lentry->namelen, value, valuelen);
+}
+
+/*
+ * Record a remote format extended attribute key & value for later reinsertion
+ * into the inode.
+ */
+STATIC int
+xrep_xattr_salvage_remote_attr(
+ struct xrep_xattr *rx,
+ struct xfs_attr_leaf_entry *ent,
+ unsigned int nameidx,
+ const char *buf_end,
+ struct xfs_attr_leaf_name_remote *rentry,
+ unsigned int ent_idx,
+ struct xfs_buf *leaf_bp)
+{
+ struct xfs_da_args args = {
+ .trans = rx->sc->tp,
+ .dp = rx->sc->ip,
+ .index = ent_idx,
+ .geo = rx->sc->mp->m_attr_geo,
+ .owner = rx->sc->ip->i_ino,
+ };
+ struct xchk_xattr_buf *ab = rx->sc->buf;
+ unsigned int valuelen;
+ unsigned int namesize;
+ int error;
+
+ /*
+ * Decode the leaf remote entry format. If something seems wrong, we
+ * junk the attribute. Note that we should never find a zero-length
+ * remote attribute value.
+ */
+ valuelen = be32_to_cpu(rentry->valuelen);
+ namesize = xfs_attr_leaf_entsize_remote(rentry->namelen);
+ if ((char *)rentry + namesize > buf_end)
+ return 0;
+ if (valuelen == 0 ||
+ !xrep_xattr_want_salvage(rx, ent->flags, rentry->name,
+ rentry->namelen, NULL, valuelen))
+ return 0;
+ if (!xchk_xattr_set_map(rx->sc, ab->usedmap, nameidx, namesize))
+ return 0;
+
+ /*
+ * Enlarge the buffer (if needed) to hold the value that we're trying
+ * to salvage from the old extended attribute data.
+ */
+ error = xchk_setup_xattr_buf(rx->sc, valuelen);
+ if (error == -ENOMEM)
+ error = -EDEADLOCK;
+ if (error)
+ return error;
+
+ /* Look up the remote value and stash it for reconstruction. */
+ args.valuelen = valuelen;
+ args.namelen = rentry->namelen;
+ args.name = rentry->name;
+ args.value = ab->value;
+ error = xfs_attr3_leaf_getvalue(leaf_bp, &args);
+ if (error || args.rmtblkno == 0)
+ goto err_free;
+
+ error = xfs_attr_rmtval_get(&args);
+ if (error)
+ goto err_free;
+
+ /* Try to save this attribute. */
+ error = xrep_xattr_salvage_key(rx, ent->flags, rentry->name,
+ rentry->namelen, ab->value, valuelen);
+err_free:
+ /* remote value was garbage, junk it */
+ if (error == -EFSBADCRC || error == -EFSCORRUPTED)
+ error = 0;
+ return error;
+}
+
+/* Extract every xattr key that we can from this attr fork block. */
+STATIC int
+xrep_xattr_recover_leaf(
+ struct xrep_xattr *rx,
+ struct xfs_buf *bp)
+{
+ struct xfs_attr3_icleaf_hdr leafhdr;
+ struct xfs_scrub *sc = rx->sc;
+ struct xfs_mount *mp = sc->mp;
+ struct xfs_attr_leafblock *leaf;
+ struct xfs_attr_leaf_name_local *lentry;
+ struct xfs_attr_leaf_name_remote *rentry;
+ struct xfs_attr_leaf_entry *ent;
+ struct xfs_attr_leaf_entry *entries;
+ struct xchk_xattr_buf *ab = rx->sc->buf;
+ char *buf_end;
+ size_t off;
+ unsigned int nameidx;
+ unsigned int hdrsize;
+ int i;
+ int error = 0;
+
+ bitmap_zero(ab->usedmap, mp->m_attr_geo->blksize);
+
+ /* Check the leaf header */
+ leaf = bp->b_addr;
+ xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo, &leafhdr, leaf);
+ hdrsize = xfs_attr3_leaf_hdr_size(leaf);
+ xchk_xattr_set_map(sc, ab->usedmap, 0, hdrsize);
+ entries = xfs_attr3_leaf_entryp(leaf);
+
+ buf_end = (char *)bp->b_addr + mp->m_attr_geo->blksize;
+ for (i = 0, ent = entries; i < leafhdr.count; ent++, i++) {
+ if (xchk_should_terminate(sc, &error))
+ return error;
+
+ /* Skip key if it conflicts with something else? */
+ off = (char *)ent - (char *)leaf;
+ if (!xchk_xattr_set_map(sc, ab->usedmap, off,
+ sizeof(xfs_attr_leaf_entry_t)))
+ continue;
+
+ /* Check the name information. */
+ nameidx = be16_to_cpu(ent->nameidx);
+ if (nameidx < leafhdr.firstused ||
+ nameidx >= mp->m_attr_geo->blksize)
+ continue;
+
+ if (ent->flags & XFS_ATTR_LOCAL) {
+ lentry = xfs_attr3_leaf_name_local(leaf, i);
+ error = xrep_xattr_salvage_local_attr(rx, ent, nameidx,
+ buf_end, lentry);
+ } else {
+ rentry = xfs_attr3_leaf_name_remote(leaf, i);
+ error = xrep_xattr_salvage_remote_attr(rx, ent, nameidx,
+ buf_end, rentry, i, bp);
+ }
+ if (error)
+ return error;
+ }
+
+ return 0;
+}
+
+/* Try to recover shortform attrs. */
+STATIC int
+xrep_xattr_recover_sf(
+ struct xrep_xattr *rx)
+{
+ struct xfs_scrub *sc = rx->sc;
+ struct xchk_xattr_buf *ab = sc->buf;
+ struct xfs_attr_shortform *sf;
+ struct xfs_attr_sf_entry *sfe;
+ struct xfs_attr_sf_entry *next;
+ struct xfs_ifork *ifp;
+ unsigned char *end;
+ int i;
+ int error = 0;
+
+ ifp = xfs_ifork_ptr(rx->sc->ip, XFS_ATTR_FORK);
+
+ bitmap_zero(ab->usedmap, ifp->if_bytes);
+ sf = (struct xfs_attr_shortform *)rx->sc->ip->i_af.if_u1.if_data;
+ end = (unsigned char *)ifp->if_u1.if_data + ifp->if_bytes;
+ xchk_xattr_set_map(sc, ab->usedmap, 0, sizeof(sf->hdr));
+
+ sfe = &sf->list[0];
+ if ((unsigned char *)sfe > end)
+ return 0;
+
+ for (i = 0; i < sf->hdr.count; i++) {
+ if (xchk_should_terminate(sc, &error))
+ return error;
+
+ next = xfs_attr_sf_nextentry(sfe);
+ if ((unsigned char *)next > end)
+ break;
+
+ if (xchk_xattr_set_map(sc, ab->usedmap,
+ (char *)sfe - (char *)sf,
+ sizeof(struct xfs_attr_sf_entry))) {
+ /*
+ * No conflicts with the sf entry; let's save this
+ * attribute.
+ */
+ error = xrep_xattr_salvage_sf_attr(rx, sf, sfe);
+ if (error)
+ return error;
+ }
+
+ sfe = next;
+ }
+
+ return 0;
+}
+
+/*
+ * Try to return a buffer of xattr data for a given physical extent.
+ *
+ * Because the buffer cache get function complains if it finds a buffer
+ * matching the block number but not matching the length, we must be careful to
+ * look for incore buffers (up to the maximum length of a remote value) that
+ * could be hiding anywhere in the physical range. If we find an incore
+ * buffer, we can pass that to the caller. Optionally, read a single block and
+ * pass that back.
+ *
+ * Note the subtlety that remote attr value blocks for which there is no incore
+ * buffer will be passed to the callback one block at a time. These buffers
+ * will not have any ops attached and must be staled to prevent aliasing with
+ * multiblock buffers once we drop the ILOCK.
+ */
+STATIC int
+xrep_xattr_find_buf(
+ struct xfs_mount *mp,
+ xfs_fsblock_t fsbno,
+ xfs_extlen_t max_len,
+ bool can_read,
+ struct xfs_buf **bpp)
+{
+ struct xrep_bufscan scan = {
+ .daddr = XFS_FSB_TO_DADDR(mp, fsbno),
+ .max_sectors = xrep_bufscan_max_sectors(mp, max_len),
+ .daddr_step = XFS_FSB_TO_BB(mp, 1),
+ };
+ struct xfs_buf *bp;
+
+ while ((bp = xrep_bufscan_advance(mp, &scan)) != NULL) {
+ *bpp = bp;
+ return 0;
+ }
+
+ if (!can_read) {
+ *bpp = NULL;
+ return 0;
+ }
+
+ return xfs_buf_read(mp->m_ddev_targp, scan.daddr, XFS_FSB_TO_BB(mp, 1),
+ XBF_TRYLOCK, bpp, NULL);
+}
+
+/*
+ * Deal with a buffer that we found during our walk of the attr fork.
+ *
+ * Attribute leaf and node blocks are simple -- they're a single block, so we
+ * can walk them one at a time and we never have to worry about discontiguous
+ * multiblock buffers like we do for directories.
+ *
+ * Unfortunately, remote attr blocks add a lot of complexity here. Each disk
+ * block is totally self contained, in the sense that the v5 header provides no
+ * indication that there could be more data in the next block. The incore
+ * buffers can span multiple blocks, though they never cross extent records.
+ * However, they don't necessarily start or end on an extent record boundary.
+ * Therefore, we need a special buffer find function to walk the buffer cache
+ * for us.
+ *
+ * The caller must hold the ILOCK on the file being repaired. We use
+ * XBF_TRYLOCK here to skip any locked buffer on the assumption that we don't
+ * own the block and don't want to hang the system on a potentially garbage
+ * buffer.
+ */
+STATIC int
+xrep_xattr_recover_block(
+ struct xrep_xattr *rx,
+ xfs_dablk_t dabno,
+ xfs_fsblock_t fsbno,
+ xfs_extlen_t max_len,
+ xfs_extlen_t *actual_len)
+{
+ struct xfs_da_blkinfo *info;
+ struct xfs_buf *bp;
+ int error;
+
+ error = xrep_xattr_find_buf(rx->sc->mp, fsbno, max_len, true, &bp);
+ if (error)
+ return error;
+ info = bp->b_addr;
+ *actual_len = XFS_BB_TO_FSB(rx->sc->mp, bp->b_length);
+
+ trace_xrep_xattr_recover_leafblock(rx->sc->ip, dabno,
+ be16_to_cpu(info->magic));
+
+ /*
+ * If the buffer has the right magic number for an attr leaf block and
+ * passes a structure check (we don't care about checksums), salvage
+ * as much as we can from the block. */
+ if (info->magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC) &&
+ xrep_buf_verify_struct(bp, &xfs_attr3_leaf_buf_ops) &&
+ xfs_attr3_leaf_header_check(bp, rx->sc->ip->i_ino) == NULL)
+ error = xrep_xattr_recover_leaf(rx, bp);
+
+ /*
+ * If the buffer didn't already have buffer ops set, it was read in by
+ * the _find_buf function and could very well be /part/ of a multiblock
+ * remote block. Mark it stale so that it doesn't hang around in
+ * memory to cause problems.
+ */
+ if (bp->b_ops == NULL)
+ xfs_buf_stale(bp);
+
+ xfs_buf_relse(bp);
+ return error;
+}
+
+/* Insert one xattr key/value. */
+STATIC int
+xrep_xattr_insert_rec(
+ struct xrep_xattr *rx,
+ const struct xrep_xattr_key *key)
+{
+ struct xfs_da_args args = {
+ .dp = rx->sc->tempip,
+ .attr_filter = key->flags,
+ .attr_flags = XATTR_CREATE,
+ .namelen = key->namelen,
+ .valuelen = key->valuelen,
+ .op_flags = XFS_DA_OP_NOTIME,
+ .owner = rx->sc->ip->i_ino,
+ };
+ struct xchk_xattr_buf *ab = rx->sc->buf;
+ int error;
+
+ /*
+ * Grab pointers to the scrub buffer so that we can use them to insert
+ * attrs into the temp file.
+ */
+ args.name = ab->name;
+ args.value = ab->value;
+
+ /*
+ * The attribute name is stored near the end of the in-core buffer,
+ * though we reserve one more byte to ensure null termination.
+ */
+ ab->name[XATTR_NAME_MAX] = 0;
+
+ error = xfblob_load(rx->xattr_blobs, key->name_cookie, ab->name,
+ key->namelen);
+ if (error)
+ return error;
+
+ error = xfblob_free(rx->xattr_blobs, key->name_cookie);
+ if (error)
+ return error;
+
+ error = xfblob_load(rx->xattr_blobs, key->value_cookie, args.value,
+ key->valuelen);
+ if (error)
+ return error;
+
+ error = xfblob_free(rx->xattr_blobs, key->value_cookie);
+ if (error)
+ return error;
+
+ ab->name[key->namelen] = 0;
+
+ trace_xrep_xattr_insert_rec(rx->sc->tempip, key->flags, ab->name,
+ key->namelen, key->valuelen);
+
+ /*
+ * xfs_attr_set creates and commits its own transaction. If the attr
+ * already exists, we'll just drop it during the rebuild.
+ */
+ error = xfs_attr_set(&args);
+ if (error == -EEXIST)
+ error = 0;
+
+ return error;
+}
+
+/*
+ * Periodically flush salvaged attributes to the temporary file. This is done
+ * to reduce the memory requirements of the xattr rebuild because files can
+ * contain millions of attributes.
+ */
+STATIC int
+xrep_xattr_flush_stashed(
+ struct xrep_xattr *rx)
+{
+ xfarray_idx_t array_cur;
+ int error;
+
+ /*
+ * Entering this function, the scrub context has a reference to the
+ * inode being repaired, the temporary file, and a scrub transaction
+ * that we use during xattr salvaging to avoid livelocking if there
+ * are cycles in the xattr structures. We hold ILOCK_EXCL on both
+ * the inode being repaired, though it is not ijoined to the scrub
+ * transaction.
+ *
+ * To constrain kernel memory use, we occasionally flush salvaged
+ * xattrs from the xfarray and xfblob structures into the temporary
+ * file in preparation for swapping the xattr structures at the end.
+ * Updating the temporary file requires a transaction, so we commit the
+ * scrub transaction and drop the two ILOCKs so that xfs_attr_set can
+ * allocate whatever transaction it wants.
+ *
+ * We still hold IOLOCK_EXCL on the inode being repaired, which
+ * prevents anyone from modifying the damaged xattr data while we
+ * repair it.
+ */
+ error = xrep_trans_commit(rx->sc);
+ if (error)
+ return error;
+ xchk_iunlock(rx->sc, XFS_ILOCK_EXCL);
+
+ /*
+ * Take the IOLOCK of the temporary file while we modify xattrs. This
+ * isn't strictly required because the temporary file is never revealed
+ * to userspace, but we follow the same locking rules. We still hold
+ * sc->ip's IOLOCK.
+ */
+ error = xrep_tempfile_iolock_polled(rx->sc);
+ if (error)
+ return error;
+
+ /* Add all the salvaged attrs to the temporary file. */
+ foreach_xfarray_idx(rx->xattr_records, array_cur) {
+ struct xrep_xattr_key key;
+
+ error = xfarray_load(rx->xattr_records, array_cur, &key);
+ if (error)
+ return error;
+
+ error = xrep_xattr_insert_rec(rx, &key);
+ if (error)
+ return error;
+ }
+
+ /* Empty out both arrays now that we've added the entries. */
+ xfarray_truncate(rx->xattr_records);
+ xfblob_truncate(rx->xattr_blobs);
+
+ xrep_tempfile_iounlock(rx->sc);
+
+ /* Recreate the salvage transaction and relock the inode. */
+ error = xchk_trans_alloc(rx->sc, 0);
+ if (error)
+ return error;
+ xchk_ilock(rx->sc, XFS_ILOCK_EXCL);
+ return 0;
+}
+
+/* Decide if we've stashed too much xattr data in memory. */
+static inline bool
+xrep_xattr_want_flush_stashed(
+ struct xrep_xattr *rx)
+{
+ unsigned long long bytes;
+
+ bytes = xfarray_bytes(rx->xattr_records) +
+ xfblob_bytes(rx->xattr_blobs);
+ return bytes > XREP_XATTR_MAX_STASH_BYTES;
+}
+
+/* Extract as many attribute keys and values as we can. */
+STATIC int
+xrep_xattr_recover(
+ struct xrep_xattr *rx)
+{
+ struct xfs_bmbt_irec got;
+ struct xfs_scrub *sc = rx->sc;
+ struct xfs_da_geometry *geo = sc->mp->m_attr_geo;
+ xfs_fileoff_t offset;
+ xfs_extlen_t len;
+ xfs_dablk_t dabno;
+ int nmap;
+ int error;
+
+ /*
+ * Iterate each xattr leaf block in the attr fork to scan them for any
+ * attributes that we might salvage.
+ */
+ for (offset = 0;
+ offset < XFS_MAX_FILEOFF;
+ offset = got.br_startoff + got.br_blockcount) {
+ nmap = 1;
+ error = xfs_bmapi_read(sc->ip, offset, XFS_MAX_FILEOFF - offset,
+ &got, &nmap, XFS_BMAPI_ATTRFORK);
+ if (error)
+ return error;
+ if (nmap != 1)
+ return -EFSCORRUPTED;
+ if (!xfs_bmap_is_written_extent(&got))
+ continue;
+
+ for (dabno = round_up(got.br_startoff, geo->fsbcount);
+ dabno < got.br_startoff + got.br_blockcount;
+ dabno += len) {
+ xfs_fileoff_t curr_offset = dabno - got.br_startoff;
+ xfs_extlen_t maxlen;
+
+ if (xchk_should_terminate(rx->sc, &error))
+ return error;
+
+ maxlen = min_t(xfs_filblks_t, INT_MAX,
+ got.br_blockcount - curr_offset);
+ error = xrep_xattr_recover_block(rx, dabno,
+ curr_offset + got.br_startblock,
+ maxlen, &len);
+ if (error)
+ return error;
+
+ if (xrep_xattr_want_flush_stashed(rx)) {
+ error = xrep_xattr_flush_stashed(rx);
+ if (error)
+ return error;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Reset the extended attribute fork to a state where we can start re-adding
+ * the salvaged attributes.
+ */
+STATIC int
+xrep_xattr_fork_remove(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip)
+{
+ struct xfs_attr_sf_hdr *hdr;
+ struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_ATTR_FORK);
+
+ /*
+ * If the data fork is in btree format, we can't change di_forkoff
+ * because we could run afoul of the rule that the data fork isn't
+ * supposed to be in btree format if there's enough space in the fork
+ * that it could have used extents format. Instead, reinitialize the
+ * attr fork to have a shortform structure with zero attributes.
+ */
+ if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE) {
+ ifp->if_format = XFS_DINODE_FMT_LOCAL;
+ xfs_idata_realloc(ip, (int)sizeof(*hdr) - ifp->if_bytes,
+ XFS_ATTR_FORK);
+ hdr = (struct xfs_attr_sf_hdr *)ifp->if_u1.if_data;
+ hdr->count = 0;
+ hdr->totsize = cpu_to_be16(sizeof(*hdr));
+ xfs_trans_log_inode(sc->tp, ip,
+ XFS_ILOG_CORE | XFS_ILOG_ADATA);
+ return 0;
+ }
+
+ /* If we still have attr fork extents, something's wrong. */
+ if (ifp->if_nextents != 0) {
+ struct xfs_iext_cursor icur;
+ struct xfs_bmbt_irec irec;
+ unsigned int i = 0;
+
+ xfs_emerg(sc->mp,
+ "inode 0x%llx attr fork still has %llu attr extents, format %d?!",
+ ip->i_ino, ifp->if_nextents, ifp->if_format);
+ for_each_xfs_iext(ifp, &icur, &irec) {
+ xfs_err(sc->mp,
+ "[%u]: startoff %llu startblock %llu blockcount %llu state %u",
+ i++, irec.br_startoff,
+ irec.br_startblock, irec.br_blockcount,
+ irec.br_state);
+ }
+ ASSERT(0);
+ return -EFSCORRUPTED;
+ }
+
+ xfs_attr_fork_remove(ip, sc->tp);
+ return 0;
+}
+
+/*
+ * Free all the attribute fork blocks of the file being repaired and delete the
+ * fork. The caller must ILOCK the scrub file and join it to the transaction.
+ * This function returns with the inode joined to a clean transaction.
+ */
+int
+xrep_xattr_reset_fork(
+ struct xfs_scrub *sc)
+{
+ int error;
+
+ trace_xrep_xattr_reset_fork(sc->ip, sc->ip);
+
+ /* Unmap all the attr blocks. */
+ if (xfs_ifork_has_extents(&sc->ip->i_af)) {
+ error = xrep_reap_ifork(sc, sc->ip, XFS_ATTR_FORK);
+ if (error)
+ return error;
+ }
+
+ error = xrep_xattr_fork_remove(sc, sc->ip);
+ if (error)
+ return error;
+
+ return xfs_trans_roll_inode(&sc->tp, sc->ip);
+}
+
+/*
+ * Free all the attribute fork blocks of the temporary file and delete the attr
+ * fork. The caller must ILOCK the tempfile and join it to the transaction.
+ * This function returns with the inode joined to a clean scrub transaction.
+ */
+STATIC int
+xrep_xattr_reset_tempfile_fork(
+ struct xfs_scrub *sc)
+{
+ int error;
+
+ trace_xrep_xattr_reset_fork(sc->ip, sc->tempip);
+
+ /*
+ * Wipe out the attr fork of the temp file so that regular inode
+ * inactivation won't trip over the corrupt attr fork.
+ */
+ if (xfs_ifork_has_extents(&sc->tempip->i_af)) {
+ error = xrep_reap_ifork(sc, sc->tempip, XFS_ATTR_FORK);
+ if (error)
+ return error;
+ }
+
+ return xrep_xattr_fork_remove(sc, sc->tempip);
+}
+
+/*
+ * Find all the extended attributes for this inode by scraping them out of the
+ * attribute key blocks by hand, and flushing them into the temp file.
+ * When we're done, free the staging memory before swapping the xattr
+ * structures to reduce memory usage.
+ */
+STATIC int
+xrep_xattr_salvage_attributes(
+ struct xrep_xattr *rx)
+{
+ struct xfs_inode *ip = rx->sc->ip;
+ int error;
+
+ /* Short format xattrs are easy! */
+ if (rx->sc->ip->i_af.if_format == XFS_DINODE_FMT_LOCAL) {
+ error = xrep_xattr_recover_sf(rx);
+ if (error)
+ return error;
+
+ return xrep_xattr_flush_stashed(rx);
+ }
+
+ /*
+ * For non-inline xattr structures, the salvage function scans the
+ * buffer cache looking for potential attr leaf blocks. The scan
+ * requires the ability to lock any buffer found and runs independently
+ * of any transaction <-> buffer item <-> buffer linkage. Therefore,
+ * roll the transaction to ensure there are no buffers joined. We hold
+ * the ILOCK independently of the transaction.
+ */
+ error = xfs_trans_roll(&rx->sc->tp);
+ if (error)
+ return error;
+
+ error = xfs_iread_extents(rx->sc->tp, ip, XFS_ATTR_FORK);
+ if (error)
+ return error;
+
+ error = xrep_xattr_recover(rx);
+ if (error)
+ return error;
+
+ return xrep_xattr_flush_stashed(rx);
+}
+
+/*
+ * Prepare both inodes' attribute forks for extent swapping. Promote the
+ * tempfile from short format to leaf format, and if the file being repaired
+ * has a short format attr fork, turn it into an empty extent list.
+ */
+STATIC int
+xrep_xattr_swap_prep(
+ struct xfs_scrub *sc,
+ bool temp_local,
+ bool ip_local)
+{
+ int error;
+
+ /*
+ * If the tempfile's attributes are in shortform format, convert that
+ * to a single leaf extent so that we can use the atomic extent swap.
+ */
+ if (temp_local) {
+ struct xfs_da_args args = {
+ .dp = sc->tempip,
+ .geo = sc->mp->m_attr_geo,
+ .whichfork = XFS_ATTR_FORK,
+ .trans = sc->tp,
+ .total = 1,
+ .owner = sc->ip->i_ino,
+ };
+
+ error = xfs_attr_shortform_to_leaf(&args);
+ if (error)
+ return error;
+
+ /*
+ * Roll the deferred log items to get us back to a clean
+ * transaction.
+ */
+ error = xfs_defer_finish(&sc->tp);
+ if (error)
+ return error;
+ }
+
+ /*
+ * If the file being repaired had a shortform attribute fork, convert
+ * that to an empty extent list in preparation for the atomic extent
+ * swap.
+ */
+ if (ip_local) {
+ struct xfs_ifork *ifp;
+
+ ifp = xfs_ifork_ptr(sc->ip, XFS_ATTR_FORK);
+
+ xfs_idestroy_fork(ifp);
+ ifp->if_format = XFS_DINODE_FMT_EXTENTS;
+ ifp->if_nextents = 0;
+ ifp->if_bytes = 0;
+ ifp->if_u1.if_root = NULL;
+ ifp->if_height = 0;
+
+ xfs_trans_log_inode(sc->tp, sc->ip,
+ XFS_ILOG_CORE | XFS_ILOG_ADATA);
+ }
+
+ return 0;
+}
+
+/* Swap the temporary file's attribute fork with the one being repaired. */
+STATIC int
+xrep_xattr_swap(
+ struct xfs_scrub *sc,
+ struct xrep_tempswap *tx)
+{
+ bool ip_local, temp_local;
+ int error = 0;
+
+ ip_local = sc->ip->i_af.if_format == XFS_DINODE_FMT_LOCAL;
+ temp_local = sc->tempip->i_af.if_format == XFS_DINODE_FMT_LOCAL;
+
+ /*
+ * If the both files have a local format attr fork and the rebuilt
+ * xattr data would fit in the repaired file's attr fork, just copy
+ * the contents from the tempfile and declare ourselves done.
+ */
+ if (ip_local && temp_local) {
+ int forkoff;
+ int newsize;
+
+ newsize = xfs_attr_sf_totsize(sc->tempip);
+ forkoff = xfs_attr_shortform_bytesfit(sc->ip, newsize);
+ if (forkoff > 0) {
+ sc->ip->i_forkoff = forkoff;
+ xrep_tempfile_copyout_local(sc, XFS_ATTR_FORK);
+ return 0;
+ }
+ }
+
+ /* Otherwise, make sure both attr forks are in block-mapping mode. */
+ error = xrep_xattr_swap_prep(sc, temp_local, ip_local);
+ if (error)
+ return error;
+
+ return xrep_tempswap_contents(sc, tx);
+}
+
+/*
+ * Swap the new extended attribute data (which we created in the tempfile) into
+ * the file being repaired.
+ */
+STATIC int
+xrep_xattr_rebuild_tree(
+ struct xrep_xattr *rx)
+{
+ struct xfs_scrub *sc = rx->sc;
+ int error;
+
+ /*
+ * If we didn't find any attributes to salvage, repair the file by
+ * zapping its attr fork.
+ */
+ if (rx->attrs_found == 0) {
+ xfs_trans_ijoin(sc->tp, sc->ip, 0);
+ error = xrep_xattr_reset_fork(sc);
+ if (error)
+ return error;
+
+ goto forget_acls;
+ }
+
+ trace_xrep_xattr_rebuild_tree(sc->ip, sc->tempip);
+
+ /*
+ * Commit the repair transaction and drop the ILOCKs so that we can use
+ * the atomic extent swap helper functions to compute the correct
+ * resource reservations.
+ *
+ * We still hold IOLOCK_EXCL (aka i_rwsem) which will prevent xattr
+ * modifications, but there's nothing to prevent userspace from reading
+ * the attributes until we're ready for the swap operation. Reads will
+ * return -EIO without shutting down the fs, so we're ok with that.
+ */
+ error = xrep_trans_commit(sc);
+ if (error)
+ return error;
+
+ xchk_iunlock(sc, XFS_ILOCK_EXCL);
+
+ /*
+ * Take the IOLOCK on the temporary file so that we can run xattr
+ * operations with the same locks held as we would for a normal file.
+ * We still hold sc->ip's IOLOCK.
+ */
+ error = xrep_tempfile_iolock_polled(rx->sc);
+ if (error)
+ return error;
+
+ /* Allocate swapext transaction and lock both inodes. */
+ error = xrep_tempswap_trans_alloc(rx->sc, XFS_ATTR_FORK, &rx->tx);
+ if (error)
+ return error;
+
+ /*
+ * Exchange the blocks mapped by the tempfile's attr fork with the file
+ * being repaired. The old attr blocks will then be attached to the
+ * tempfile, so reap its attr fork.
+ */
+ error = xrep_xattr_swap(sc, &rx->tx);
+ if (error)
+ return error;
+
+ error = xrep_xattr_reset_tempfile_fork(sc);
+ if (error)
+ return error;
+
+ /*
+ * Roll to get a transaction without any inodes joined to it. Then we
+ * can drop the tempfile's ILOCK and IOLOCK before doing more work on
+ * the scrub target file.
+ */
+ error = xfs_trans_roll(&sc->tp);
+ if (error)
+ return error;
+
+ xrep_tempfile_iunlock(sc);
+ xrep_tempfile_iounlock(sc);
+
+forget_acls:
+ /* Invalidate cached ACLs now that we've reloaded all the xattrs. */
+ xfs_forget_acl(VFS_I(sc->ip), SGI_ACL_FILE);
+ xfs_forget_acl(VFS_I(sc->ip), SGI_ACL_DEFAULT);
+ return 0;
+}
+
+/* Tear down all the incore scan stuff we created. */
+STATIC void
+xrep_xattr_teardown(
+ struct xrep_xattr *rx)
+{
+ xfblob_destroy(rx->xattr_blobs);
+ xfarray_destroy(rx->xattr_records);
+ kfree(rx);
+}
+
+/* Set up the filesystem scan so we can regenerate extended attributes. */
+STATIC int
+xrep_xattr_setup_scan(
+ struct xfs_scrub *sc,
+ struct xrep_xattr **rxp)
+{
+ struct xrep_xattr *rx;
+ char *descr;
+ int max_len;
+ int error;
+
+ rx = kzalloc(sizeof(struct xrep_xattr), XCHK_GFP_FLAGS);
+ if (!rx)
+ return -ENOMEM;
+ rx->sc = sc;
+
+ /*
+ * Allocate enough memory to handle loading local attr values from the
+ * xfblob data while flushing stashed attrs to the temporary file.
+ * We only realloc the buffer when salvaging remote attr values.
+ */
+ max_len = xfs_attr_leaf_entsize_local_max(sc->mp->m_attr_geo->blksize);
+ error = xchk_setup_xattr_buf(rx->sc, max_len);
+ if (error == -ENOMEM)
+ error = -EDEADLOCK;
+ if (error)
+ goto out_rx;
+
+ /* Set up some staging for salvaged attribute keys and values */
+ descr = xchk_xfile_ino_descr(sc, "xattr keys");
+ error = xfarray_create(descr, 0, sizeof(struct xrep_xattr_key),
+ &rx->xattr_records);
+ kfree(descr);
+ if (error)
+ goto out_rx;
+
+ descr = xchk_xfile_ino_descr(sc, "xattr names");
+ error = xfblob_create(descr, &rx->xattr_blobs);
+ kfree(descr);
+ if (error)
+ goto out_keys;
+
+ *rxp = rx;
+ return 0;
+out_keys:
+ xfarray_destroy(rx->xattr_records);
+out_rx:
+ kfree(rx);
+ return error;
+}
+
+/*
+ * Repair the extended attribute metadata.
+ *
+ * XXX: Remote attribute value buffers encompass the entire (up to 64k) buffer.
+ * The buffer cache in XFS can't handle aliased multiblock buffers, so this
+ * might misbehave if the attr fork is crosslinked with other filesystem
+ * metadata.
+ */
+int
+xrep_xattr(
+ struct xfs_scrub *sc)
+{
+ struct xrep_xattr *rx = NULL;
+ int error;
+
+ if (!xfs_inode_hasattr(sc->ip))
+ return -ENOENT;
+
+ /* The rmapbt is required to reap the old attr fork. */
+ if (!xfs_has_rmapbt(sc->mp))
+ return -EOPNOTSUPP;
+
+ error = xrep_xattr_setup_scan(sc, &rx);
+ if (error)
+ return error;
+
+ ASSERT(sc->ilock_flags & XFS_ILOCK_EXCL);
+
+ error = xrep_xattr_salvage_attributes(rx);
+ if (error)
+ goto out_scan;
+
+ /* Last chance to abort before we start committing fixes. */
+ if (xchk_should_terminate(sc, &error))
+ goto out_scan;
+
+ error = xrep_xattr_rebuild_tree(rx);
+ if (error)
+ goto out_scan;
+
+out_scan:
+ xrep_xattr_teardown(rx);
+ return error;
+}
diff --git a/fs/xfs/scrub/attr_repair.h b/fs/xfs/scrub/attr_repair.h
new file mode 100644
index 0000000000000..0a9ffa7cfa906
--- /dev/null
+++ b/fs/xfs/scrub/attr_repair.h
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2018-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#ifndef __XFS_SCRUB_ATTR_REPAIR_H__
+#define __XFS_SCRUB_ATTR_REPAIR_H__
+
+int xrep_xattr_reset_fork(struct xfs_scrub *sc);
+
+#endif /* __XFS_SCRUB_ATTR_REPAIR_H__ */
diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c
index 6490f064e091f..83b7aa48dec19 100644
--- a/fs/xfs/scrub/repair.c
+++ b/fs/xfs/scrub/repair.c
@@ -32,6 +32,9 @@
#include "xfs_reflink.h"
#include "xfs_health.h"
#include "xfs_buf_xfile.h"
+#include "xfs_da_format.h"
+#include "xfs_da_btree.h"
+#include "xfs_attr.h"
#include "scrub/scrub.h"
#include "scrub/common.h"
#include "scrub/trace.h"
@@ -39,6 +42,7 @@
#include "scrub/bitmap.h"
#include "scrub/stats.h"
#include "scrub/xfile.h"
+#include "scrub/attr_repair.h"

/*
* Attempt to repair some metadata, if the metadata is corrupt and userspace
@@ -1136,6 +1140,17 @@ xrep_metadata_inode_forks(
return error;
}

+ /* Clear the attr forks since metadata shouldn't have that. */
+ if (xfs_inode_hasattr(sc->ip)) {
+ if (!dirty) {
+ dirty = true;
+ xfs_trans_ijoin(sc->tp, sc->ip, 0);
+ }
+ error = xrep_xattr_reset_fork(sc);
+ if (error)
+ return error;
+ }
+
/*
* If we modified the inode, roll the transaction but don't rejoin the
* inode to the new transaction because xrep_bmap_data can do that.
@@ -1201,3 +1216,34 @@ xrep_trans_cancel_hook_dummy(
current->journal_info = *cookiep;
*cookiep = NULL;
}
+
+/*
+ * See if this buffer can pass the given ->verify_struct() function.
+ *
+ * If the buffer already has ops attached and they're not the ones that were
+ * passed in, we reject the buffer. Otherwise, we perform the structure test
+ * (note that we do not check CRCs) and return the outcome of the test. The
+ * buffer ops and error state are left unchanged.
+ */
+bool
+xrep_buf_verify_struct(
+ struct xfs_buf *bp,
+ const struct xfs_buf_ops *ops)
+{
+ const struct xfs_buf_ops *old_ops = bp->b_ops;
+ xfs_failaddr_t fa;
+ int old_error;
+
+ if (old_ops) {
+ if (old_ops != ops)
+ return false;
+ }
+
+ old_error = bp->b_error;
+ bp->b_ops = ops;
+ fa = bp->b_ops->verify_struct(bp);
+ bp->b_ops = old_ops;
+ bp->b_error = old_error;
+
+ return fa == NULL;
+}
diff --git a/fs/xfs/scrub/repair.h b/fs/xfs/scrub/repair.h
index 06125d0a2c602..2bc5dd18d46f4 100644
--- a/fs/xfs/scrub/repair.h
+++ b/fs/xfs/scrub/repair.h
@@ -90,6 +90,7 @@ int xrep_bmap(struct xfs_scrub *sc, int whichfork, bool allow_unwritten);
int xrep_metadata_inode_forks(struct xfs_scrub *sc);
int xrep_setup_ag_rmapbt(struct xfs_scrub *sc);
int xrep_setup_ag_refcountbt(struct xfs_scrub *sc);
+int xrep_setup_xattr(struct xfs_scrub *sc);

/* Repair setup functions */
int xrep_setup_ag_allocbt(struct xfs_scrub *sc);
@@ -123,6 +124,7 @@ int xrep_bmap_attr(struct xfs_scrub *sc);
int xrep_bmap_cow(struct xfs_scrub *sc);
int xrep_nlinks(struct xfs_scrub *sc);
int xrep_fscounters(struct xfs_scrub *sc);
+int xrep_xattr(struct xfs_scrub *sc);

#ifdef CONFIG_XFS_RT
int xrep_rtbitmap(struct xfs_scrub *sc);
@@ -147,6 +149,8 @@ int xrep_trans_alloc_hook_dummy(struct xfs_mount *mp, void **cookiep,
struct xfs_trans **tpp);
void xrep_trans_cancel_hook_dummy(void **cookiep, struct xfs_trans *tp);

+bool xrep_buf_verify_struct(struct xfs_buf *bp, const struct xfs_buf_ops *ops);
+
#else

#define xrep_ino_dqattach(sc) (0)
@@ -190,6 +194,7 @@ xrep_setup_nothing(
#define xrep_setup_ag_allocbt xrep_setup_nothing
#define xrep_setup_ag_rmapbt xrep_setup_nothing
#define xrep_setup_ag_refcountbt xrep_setup_nothing
+#define xrep_setup_xattr xrep_setup_nothing

#define xrep_setup_inode(sc, imap) ((void)0)

@@ -215,6 +220,7 @@ xrep_setup_nothing(
#define xrep_nlinks xrep_notsupported
#define xrep_fscounters xrep_notsupported
#define xrep_rtsummary xrep_notsupported
+#define xrep_xattr xrep_notsupported

#endif /* CONFIG_XFS_ONLINE_REPAIR */

diff --git a/fs/xfs/scrub/scrub.c b/fs/xfs/scrub/scrub.c
index 9af91874e58b9..0b8fdd62055fe 100644
--- a/fs/xfs/scrub/scrub.c
+++ b/fs/xfs/scrub/scrub.c
@@ -334,7 +334,7 @@ static const struct xchk_meta_ops meta_scrub_ops[] = {
.type = ST_INODE,
.setup = xchk_setup_xattr,
.scrub = xchk_xattr,
- .repair = xrep_notsupported,
+ .repair = xrep_xattr,
},
[XFS_SCRUB_TYPE_SYMLINK] = { /* symbolic link */
.type = ST_INODE,
diff --git a/fs/xfs/scrub/trace.h b/fs/xfs/scrub/trace.h
index 1f06c1ace5902..ba75a56b2e2de 100644
--- a/fs/xfs/scrub/trace.h
+++ b/fs/xfs/scrub/trace.h
@@ -2497,6 +2497,89 @@ TRACE_EVENT(xreap_bmapi_binval_scan,
__entry->scan_blocks)
);

+TRACE_EVENT(xrep_xattr_recover_leafblock,
+ TP_PROTO(struct xfs_inode *ip, xfs_dablk_t dabno, uint16_t magic),
+ TP_ARGS(ip, dabno, magic),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(xfs_ino_t, ino)
+ __field(xfs_dablk_t, dabno)
+ __field(uint16_t, magic)
+ ),
+ TP_fast_assign(
+ __entry->dev = ip->i_mount->m_super->s_dev;
+ __entry->ino = ip->i_ino;
+ __entry->dabno = dabno;
+ __entry->magic = magic;
+ ),
+ TP_printk("dev %d:%d ino 0x%llx dablk 0x%x magic 0x%x",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __entry->dabno,
+ __entry->magic)
+);
+
+DECLARE_EVENT_CLASS(xrep_xattr_salvage_class,
+ TP_PROTO(struct xfs_inode *ip, unsigned int flags, char *name,
+ unsigned int namelen, unsigned int valuelen),
+ TP_ARGS(ip, flags, name, namelen, valuelen),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(xfs_ino_t, ino)
+ __field(unsigned int, flags)
+ __field(unsigned int, namelen)
+ __dynamic_array(char, name, namelen)
+ __field(unsigned int, valuelen)
+ ),
+ TP_fast_assign(
+ __entry->dev = ip->i_mount->m_super->s_dev;
+ __entry->ino = ip->i_ino;
+ __entry->flags = flags;
+ __entry->namelen = namelen;
+ memcpy(__get_str(name), name, namelen);
+ __entry->valuelen = valuelen;
+ ),
+ TP_printk("dev %d:%d ino 0x%llx flags %s name '%.*s' valuelen 0x%x",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __print_flags(__entry->flags, "|", XFS_ATTR_NAMESPACE_STR),
+ __entry->namelen,
+ __get_str(name),
+ __entry->valuelen)
+);
+#define DEFINE_XREP_XATTR_SALVAGE_EVENT(name) \
+DEFINE_EVENT(xrep_xattr_salvage_class, name, \
+ TP_PROTO(struct xfs_inode *ip, unsigned int flags, char *name, \
+ unsigned int namelen, unsigned int valuelen), \
+ TP_ARGS(ip, flags, name, namelen, valuelen))
+DEFINE_XREP_XATTR_SALVAGE_EVENT(xrep_xattr_salvage_rec);
+DEFINE_XREP_XATTR_SALVAGE_EVENT(xrep_xattr_insert_rec);
+
+TRACE_EVENT(xrep_xattr_class,
+ TP_PROTO(struct xfs_inode *ip, struct xfs_inode *arg_ip),
+ TP_ARGS(ip, arg_ip),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(xfs_ino_t, ino)
+ __field(xfs_ino_t, src_ino)
+ ),
+ TP_fast_assign(
+ __entry->dev = ip->i_mount->m_super->s_dev;
+ __entry->ino = ip->i_ino;
+ __entry->src_ino = arg_ip->i_ino;
+ ),
+ TP_printk("dev %d:%d ino 0x%llx src 0x%llx",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __entry->src_ino)
+)
+#define DEFINE_XREP_XATTR_EVENT(name) \
+DEFINE_EVENT(xrep_xattr_class, name, \
+ TP_PROTO(struct xfs_inode *ip, struct xfs_inode *arg_ip), \
+ TP_ARGS(ip, arg_ip))
+DEFINE_XREP_XATTR_EVENT(xrep_xattr_rebuild_tree);
+DEFINE_XREP_XATTR_EVENT(xrep_xattr_reset_fork);
+
#endif /* IS_ENABLED(CONFIG_XFS_ONLINE_REPAIR) */

diff --git a/fs/xfs/scrub/xfarray.c b/fs/xfs/scrub/xfarray.c
index f0f532c10a5ac..1bd690ac5d368 100644
--- a/fs/xfs/scrub/xfarray.c
+++ b/fs/xfs/scrub/xfarray.c
@@ -1081,3 +1081,20 @@ xfarray_sort(
kvfree(si);
return error;
}
+
+/* How many bytes is this array consuming? */
+unsigned long long
+xfarray_bytes(
+ struct xfarray *array)
+{
+ return xfile_bytes(array->xfile);
+}
+
+/* Empty the entire array. */
+void
+xfarray_truncate(
+ struct xfarray *array)
+{
+ xfile_discard(array->xfile, 0, MAX_LFS_FILESIZE);
+ array->nr = 0;
+}
diff --git a/fs/xfs/scrub/xfarray.h b/fs/xfs/scrub/xfarray.h
index 0f1dac3aa1916..f06af7eb484ec 100644
--- a/fs/xfs/scrub/xfarray.h
+++ b/fs/xfs/scrub/xfarray.h
@@ -44,6 +44,8 @@ int xfarray_unset(struct xfarray *array, xfarray_idx_t idx);
int xfarray_store(struct xfarray *array, xfarray_idx_t idx, const void *ptr);
int xfarray_store_anywhere(struct xfarray *array, const void *ptr);
bool xfarray_element_is_null(struct xfarray *array, const void *ptr);
+void xfarray_truncate(struct xfarray *array);
+unsigned long long xfarray_bytes(struct xfarray *array);

/*
* Load an array element, but zero the buffer if there's no data because we
diff --git a/fs/xfs/scrub/xfblob.c b/fs/xfs/scrub/xfblob.c
index 216f9cb2965a7..9c9ec90c69dbc 100644
--- a/fs/xfs/scrub/xfblob.c
+++ b/fs/xfs/scrub/xfblob.c
@@ -149,3 +149,20 @@ xfblob_free(
xfile_discard(blob->xfile, cookie, sizeof(key) + key.xb_size);
return 0;
}
+
+/* How many bytes is this blob storage object consuming? */
+unsigned long long
+xfblob_bytes(
+ struct xfblob *blob)
+{
+ return xfile_bytes(blob->xfile);
+}
+
+/* Drop all the blobs. */
+void
+xfblob_truncate(
+ struct xfblob *blob)
+{
+ xfile_discard(blob->xfile, PAGE_SIZE, MAX_LFS_FILESIZE - PAGE_SIZE);
+ blob->last_offset = PAGE_SIZE;
+}
diff --git a/fs/xfs/scrub/xfblob.h b/fs/xfs/scrub/xfblob.h
index bd98647407f1d..78a67a06408f8 100644
--- a/fs/xfs/scrub/xfblob.h
+++ b/fs/xfs/scrub/xfblob.h
@@ -20,5 +20,7 @@ int xfblob_load(struct xfblob *blob, xfblob_cookie cookie, void *ptr,
int xfblob_store(struct xfblob *blob, xfblob_cookie *cookie, const void *ptr,
uint32_t size);
int xfblob_free(struct xfblob *blob, xfblob_cookie cookie);
+unsigned long long xfblob_bytes(struct xfblob *blob);
+void xfblob_truncate(struct xfblob *blob);

#endif /* __XFS_SCRUB_XFBLOB_H__ */
diff --git a/fs/xfs/scrub/xfile.h b/fs/xfs/scrub/xfile.h
index 36061af2c1352..849f59da6a184 100644
--- a/fs/xfs/scrub/xfile.h
+++ b/fs/xfs/scrub/xfile.h
@@ -86,6 +86,18 @@ static inline loff_t xfile_size(struct xfile *xf)
return i_size_read(file_inode(xf->file));
}

+static inline unsigned long long xfile_bytes(struct xfile *xf)
+{
+ struct xfile_stat xs;
+ int ret;
+
+ ret = xfile_stat(xf, &xs);
+ if (ret)
+ return 0;
+
+ return xs.bytes;
+}
+
/* file block (aka system page size) to basic block conversions. */
typedef unsigned long long xfileoff_t;
#define XFB_BLOCKSIZE (PAGE_SIZE)
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index a61ad61cb9136..b62518968e784 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -481,6 +481,9 @@ _xfs_buf_obj_cmp(
* it stale has not yet committed. i.e. we are
* reallocating a busy extent. Skip this buffer and
* continue searching for an exact match.
+ *
+ * Note: If we're scanning for incore buffers to stale, don't
+ * complain if we find non-stale buffers.
*/
if (!(map->bm_flags & XBM_LIVESCAN))
ASSERT(bp->b_flags & XBF_STALE);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index ee6f569c2f3d9..2c838b7471191 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -31,6 +31,8 @@
* pos: file offset, in bytes
* bytecount: number of bytes
*
+ * dablk: directory or xattr block offset, in filesystem blocks
+ *
* disize: ondisk file size, in bytes
* isize: incore file size, in bytes
*