xfs
[Top] [All Lists]

[PATCH 2/4] xfs_repair: fix unaligned accesses

To: xfs@xxxxxxxxxxx
Subject: [PATCH 2/4] xfs_repair: fix unaligned accesses
From: Eric Sandeen <sandeen@xxxxxxxxxxx>
Date: Thu, 8 Oct 2015 19:25:24 -0500
Delivered-to: xfs@xxxxxxxxxxx
In-reply-to: <56170906.5090301@xxxxxxxxxx>
References: <56170906.5090301@xxxxxxxxxx>
User-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:38.0) Gecko/20100101 Thunderbird/38.3.0
This fixes some unaligned accesses spotted by libubsan in repair.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
 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

<Prev in Thread] Current Thread [Next in Thread>