[PATCH 2/4] xfs_repair: fix unaligned accesses

[Eric Sandeen <sandeen@sandeen.net>]

This fixes some unaligned accesses spotted by libubsan in repair.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---
 repair/dinode.c   |   19 +++++++++----------
 repair/prefetch.c |    4 ++--
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/repair/dinode.c b/repair/dinode.c
index f78f907..44bbb8f 100644
--- a/repair/dinode.c
+++ b/repair/dinode.c
@@ -960,13 +960,13 @@ _("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])))  {
+		if (!verify_dfsbno(mp, get_unaligned_be64(&pp[i])))  {
 			do_warn(_("bad bmap btree ptr 0x%llx in ino %" PRIu64 "\n"),
-			       (unsigned long long) be64_to_cpu(pp[i]), lino);
+			       get_unaligned_be64(&pp[i]), lino);
 			return(1);
 		}
 
-		if (scan_lbtree(be64_to_cpu(pp[i]), level, scan_bmapbt, type,
+		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);
@@ -977,25 +977,24 @@ _("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),
+					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(
+					cpu_to_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),
+					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))
-- 
1.7.1

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