ocfs2: fix NULL dereference for moving extents
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>
diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c
index 8f3d3cb..f1fc172 100644
--- a/fs/ocfs2/move_extents.c
+++ b/fs/ocfs2/move_extents.c
@@ -471,7 +471,7 @@
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);
@@ -482,13 +482,6 @@
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
*/
@@ -502,6 +495,13 @@
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.
*/
if ((le16_to_cpu(bg->bg_bits) - goal_bit) * osb->s_clustersize <