This fixes some unaligned accesses spotted by libubsan in repair.
See Documentation/unaligned-memory-access.txt in the kernel
tree for why these can be a problem.
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
V2:
Add note about why ...
Add another in libxfs_bmbt_disk_get_all
Fix mistaken double-swap in dinode.c in original patch
include/libxfs.h | 4 ++--
repair/dinode.c | 47 ++++++++++++++++++++++++-----------------------
repair/prefetch.c | 4 ++--
3 files changed, 28 insertions(+), 27 deletions(-)
diff --git a/include/libxfs.h b/include/libxfs.h
index b1604e2..52fb483 100644
--- a/include/libxfs.h
+++ b/include/libxfs.h
@@ -206,8 +206,8 @@ libxfs_bmbt_disk_get_all(
{
struct xfs_bmbt_rec_host hrec;
- hrec.l0 = be64_to_cpu(rp->l0);
- hrec.l1 = be64_to_cpu(rp->l1);
+ hrec.l0 = get_unaligned_be64(&rp->l0);
+ hrec.l1 = get_unaligned_be64(&rp->l1);
libxfs_bmbt_get_all(&hrec, irec);
}
diff --git a/repair/dinode.c b/repair/dinode.c
index f78f907..f99cba3 100644
--- a/repair/dinode.c
+++ b/repair/dinode.c
@@ -960,15 +960,17 @@ _("bad numrecs 0 in inode %" PRIu64 " bmap btree root
block\n"),
* btree, we'd do it right here. For now, if there's a
* problem, we'll bail out and presumably clear the inode.
*/
- if (!verify_dfsbno(mp, be64_to_cpu(pp[i]))) {
- do_warn(_("bad bmap btree ptr 0x%llx in ino %" PRIu64
"\n"),
- (unsigned long long) be64_to_cpu(pp[i]), lino);
+ if (!verify_dfsbno(mp, get_unaligned_be64(&pp[i]))) {
+ do_warn(
+("bad bmap btree ptr 0x%" PRIx64 " in ino %" PRIu64 "\n"),
+ get_unaligned_be64(&pp[i]), lino);
return(1);
}
- if (scan_lbtree(be64_to_cpu(pp[i]), level, scan_bmapbt, type,
- whichfork, lino, tot, nex, blkmapp, &cursor,
- 1, check_dups, magic, &xfs_bmbt_buf_ops))
+ if (scan_lbtree(get_unaligned_be64(&pp[i]), level, scan_bmapbt,
+ type, whichfork, lino, tot, nex, blkmapp,
+ &cursor, 1, check_dups, magic,
+ &xfs_bmbt_buf_ops))
return(1);
/*
* fix key (offset) mismatches between the keys in root
@@ -977,28 +979,27 @@ _("bad numrecs 0 in inode %" PRIu64 " bmap btree root
block\n"),
* blocks but the parent hasn't been updated
*/
if (!check_dups && cursor.level[level-1].first_key !=
- be64_to_cpu(pkey[i].br_startoff)) {
+ get_unaligned_be64(&pkey[i].br_startoff)) {
if (!no_modify) {
do_warn(
- _("correcting key in bmbt root (was %llu, now %" PRIu64") in inode "
- "%" PRIu64" %s fork\n"),
- (unsigned long long)
- be64_to_cpu(pkey[i].br_startoff),
- cursor.level[level-1].first_key,
- XFS_AGINO_TO_INO(mp, agno, ino),
- forkname);
+_("correcting key in bmbt root (was %" PRIu64 ", now %" PRIu64") in inode "
+ "%" PRIu64" %s fork\n"),
+ get_unaligned_be64(&pkey[i].br_startoff),
+ cursor.level[level-1].first_key,
+ XFS_AGINO_TO_INO(mp, agno, ino),
+ forkname);
*dirty = 1;
- pkey[i].br_startoff = cpu_to_be64(
- cursor.level[level-1].first_key);
+ put_unaligned_be64(
+ cursor.level[level-1].first_key,
+ &pkey[i].br_startoff);
} else {
do_warn(
- _("bad key in bmbt root (is %llu, would reset to %" PRIu64 ") in inode "
- "%" PRIu64 " %s fork\n"),
- (unsigned long long)
- be64_to_cpu(pkey[i].br_startoff),
- cursor.level[level-1].first_key,
- XFS_AGINO_TO_INO(mp, agno, ino),
- forkname);
+_("bad key in bmbt root (is %" PRIu64 ", would reset to %" PRIu64 ") in inode "
+ "%" PRIu64 " %s fork\n"),
+ get_unaligned_be64(&pkey[i].br_startoff),
+ cursor.level[level-1].first_key,
+ XFS_AGINO_TO_INO(mp, agno, ino),
+ forkname);
}
}
/*
diff --git a/repair/prefetch.c b/repair/prefetch.c
index 32ec55e..52238ca 100644
--- a/repair/prefetch.c
+++ b/repair/prefetch.c
@@ -330,7 +330,7 @@ pf_scanfunc_bmap(
pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
for (i = 0; i < numrecs; i++) {
- dbno = be64_to_cpu(pp[i]);
+ dbno = get_unaligned_be64(&pp[i]);
if (!verify_dfsbno(mp, dbno))
return 0;
if (!pf_scan_lbtree(dbno, level, isadir, args,
pf_scanfunc_bmap))
@@ -372,7 +372,7 @@ pf_read_btinode(
pp = XFS_BMDR_PTR_ADDR(dib, 1, xfs_bmdr_maxrecs(dsize, 0));
for (i = 0; i < numrecs; i++) {
- dbno = be64_to_cpu(pp[i]);
+ dbno = get_unaligned_be64(&pp[i]);
if (!verify_dfsbno(mp, dbno))
break;
if (!pf_scan_lbtree(dbno, level, isadir, args,
pf_scanfunc_bmap))
--
2.6.1
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