ocfs2: fix a tiny race when truncate dio orohaned entry

Once dio crashed it will leave an entry in orphan dir.  And orphan scan
will take care of the clean up.  There is a tiny race case that the same
entry will be truncated twice and then trigger the BUG in
ocfs2_del_inode_from_orphan.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index f906a25..395f4b3 100644 (file)
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -925,13 +925,23 @@ clean_orphan:
                int update_isize = written > 0 ? 1 : 0;
                loff_t end = update_isize ? offset + written : 0;
 
-               tmp_ret = ocfs2_del_inode_from_orphan(osb, inode,
+               tmp_ret = ocfs2_inode_lock(inode, &di_bh, 1);
+               if (tmp_ret < 0) {
+                       ret = tmp_ret;
+                       mlog_errno(ret);
+                       goto out;
+               }
+
+               tmp_ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh,
                                update_isize, end);
                if (tmp_ret < 0) {
                        ret = tmp_ret;
+                       mlog_errno(ret);
                        goto out;
                }
 
+               ocfs2_inode_unlock(inode, 1);
+
                tmp_ret = jbd2_journal_force_commit(journal);
                if (tmp_ret < 0) {
                        ret = tmp_ret;

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index ff53192..4205da0 100644 (file)
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -2137,6 +2137,8 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
        struct inode *inode = NULL;
        struct inode *iter;
        struct ocfs2_inode_info *oi;
+       struct buffer_head *di_bh = NULL;
+       struct ocfs2_dinode *di = NULL;
 
        trace_ocfs2_recover_orphans(slot);
 
@@ -2157,16 +2159,22 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                iter = oi->ip_next_orphan;
                oi->ip_next_orphan = NULL;
 
+               ret = ocfs2_rw_lock(inode, 1);
+               if (ret < 0) {
+                       mlog_errno(ret);
+                       goto next;
+               }
                /*
                 * We need to take and drop the inode lock to
                 * force read inode from disk.
                 */
-               ret = ocfs2_inode_lock(inode, NULL, 0);
+               ret = ocfs2_inode_lock(inode, &di_bh, 1);
                if (ret) {
                        mlog_errno(ret);
-                       goto next;
+                       goto unlock_rw;
                }
-               ocfs2_inode_unlock(inode, 0);
+
+               di = (struct ocfs2_dinode *)di_bh->b_data;
 
                if (inode->i_nlink == 0) {
                        spin_lock(&oi->ip_lock);
@@ -2174,43 +2182,30 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                         * ocfs2_delete_inode. */
                        oi->ip_flags |= OCFS2_INODE_MAYBE_ORPHANED;
                        spin_unlock(&oi->ip_lock);
-               } else if (orphan_reco_type == ORPHAN_NEED_TRUNCATE) {
-                       struct buffer_head *di_bh = NULL;
-
-                       ret = ocfs2_rw_lock(inode, 1);
-                       if (ret) {
-                               mlog_errno(ret);
-                               goto next;
-                       }
-
-                       ret = ocfs2_inode_lock(inode, &di_bh, 1);
-                       if (ret < 0) {
-                               ocfs2_rw_unlock(inode, 1);
-                               mlog_errno(ret);
-                               goto next;
-                       }
-
+               } else if ((orphan_reco_type == ORPHAN_NEED_TRUNCATE) &&
+                               (di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL))) {
                        ret = ocfs2_truncate_file(inode, di_bh,
                                        i_size_read(inode));
-                       ocfs2_inode_unlock(inode, 1);
-                       ocfs2_rw_unlock(inode, 1);
-                       brelse(di_bh);
                        if (ret < 0) {
                                if (ret != -ENOSPC)
                                        mlog_errno(ret);
-                               goto next;
+                               goto unlock_inode;
                        }
 
-                       ret = ocfs2_del_inode_from_orphan(osb, inode, 0, 0);
+                       ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);
                        if (ret)
                                mlog_errno(ret);
 
                        wake_up(&OCFS2_I(inode)->append_dio_wq);
                } /* else if ORPHAN_NO_NEED_TRUNCATE, do nothing */
-
+unlock_inode:
+               ocfs2_inode_unlock(inode, 1);
+unlock_rw:
+               ocfs2_rw_unlock(inode, 1);
 next:
                iput(inode);
-
+               brelse(di_bh);
+               di_bh = NULL;
                inode = iter;
        }
 

diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 176fe6a..08a7a5b 100644 (file)
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -2670,30 +2670,22 @@ bail:
 }
 
 int ocfs2_del_inode_from_orphan(struct ocfs2_super *osb,
-               struct inode *inode, int update_isize,
-               loff_t end)
+               struct inode *inode, struct buffer_head *di_bh,
+               int update_isize, loff_t end)
 {
        struct inode *orphan_dir_inode = NULL;
        struct buffer_head *orphan_dir_bh = NULL;
-       struct buffer_head *di_bh = NULL;
-       struct ocfs2_dinode *di = NULL;
+       struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
        handle_t *handle = NULL;
        int status = 0;
 
-       status = ocfs2_inode_lock(inode, &di_bh, 1);
-       if (status < 0) {
-               mlog_errno(status);
-               goto bail;
-       }
-       di = (struct ocfs2_dinode *) di_bh->b_data;
-
        orphan_dir_inode = ocfs2_get_system_file_inode(osb,
                        ORPHAN_DIR_SYSTEM_INODE,
                        le16_to_cpu(di->i_dio_orphaned_slot));
        if (!orphan_dir_inode) {
                status = -ENOENT;
                mlog_errno(status);
-               goto bail_unlock_inode;
+               goto bail;
        }
 
        mutex_lock(&orphan_dir_inode->i_mutex);
@@ -2702,7 +2694,7 @@ int ocfs2_del_inode_from_orphan(struct ocfs2_super *osb,
                mutex_unlock(&orphan_dir_inode->i_mutex);
                iput(orphan_dir_inode);
                mlog_errno(status);
-               goto bail_unlock_inode;
+               goto bail;
        }
 
        handle = ocfs2_start_trans(osb,
@@ -2749,10 +2741,6 @@ bail_unlock_orphan:
        brelse(orphan_dir_bh);
        iput(orphan_dir_inode);
 
-bail_unlock_inode:
-       ocfs2_inode_unlock(inode, 1);
-       brelse(di_bh);
-
 bail:
        return status;
 }

diff --git a/fs/ocfs2/namei.h b/fs/ocfs2/namei.h
index 5ddecce..e173329 100644 (file)
--- a/fs/ocfs2/namei.h
+++ b/fs/ocfs2/namei.h
@@ -42,8 +42,8 @@ int ocfs2_create_inode_in_orphan(struct inode *dir,
 int ocfs2_add_inode_to_orphan(struct ocfs2_super *osb,
                struct inode *inode);
 int ocfs2_del_inode_from_orphan(struct ocfs2_super *osb,
-               struct inode *inode, int update_isize,
-               loff_t end);
+               struct inode *inode, struct buffer_head *di_bh,
+               int update_isize, loff_t end);
 int ocfs2_mv_orphaned_inode_to_new(struct inode *dir,
                                   struct inode *new_inode,
                                   struct dentry *new_dentry);