ocfs2: fix NULL dereference for moving extents
authorDan Carpenter <dan.carpenter@oracle.com>
Mon, 29 Apr 2013 22:05:59 +0000 (15:05 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Mon, 29 Apr 2013 22:54:27 +0000 (15:54 -0700)
We can't dereference "bg" before it has been assigned.  GCC should have
warned about this but "bg" was initialized to NULL.  I've fixed that as
well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.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>
fs/ocfs2/move_extents.c

index 8f3d3cb7fa9799b7cc7ae0bcd9a555a1da4b650f..f1fc172175b6c47454cfbb4f10bfd239102e92a9 100644 (file)
@@ -471,7 +471,7 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
        int ret, goal_bit = 0;
 
        struct buffer_head *gd_bh = NULL;
-       struct ocfs2_group_desc *bg = NULL;
+       struct ocfs2_group_desc *bg;
        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
        int c_to_b = 1 << (osb->s_clustersize_bits -
                                        inode->i_sb->s_blocksize_bits);
@@ -481,13 +481,6 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
         */
        range->me_goal = ocfs2_block_to_cluster_start(inode->i_sb,
                                                      range->me_goal);
-       /*
-        * moving goal is not allowd to start with a group desc blok(#0 blk)
-        * let's compromise to the latter cluster.
-        */
-       if (range->me_goal == le64_to_cpu(bg->bg_blkno))
-               range->me_goal += c_to_b;
-
        /*
         * validate goal sits within global_bitmap, and return the victim
         * group desc
@@ -501,6 +494,13 @@ static int ocfs2_validate_and_adjust_move_goal(struct inode *inode,
 
        bg = (struct ocfs2_group_desc *)gd_bh->b_data;
 
+       /*
+        * moving goal is not allowd to start with a group desc blok(#0 blk)
+        * let's compromise to the latter cluster.
+        */
+       if (range->me_goal == le64_to_cpu(bg->bg_blkno))
+               range->me_goal += c_to_b;
+
        /*
         * movement is not gonna cross two groups.
         */