ocfs2: Respond to on-disk corruption in the extent map code.

The extent map code has long noticed when the on-disk extent information
is corrupt.  However, so far it has only returned an error.  We should
take the filesystem read-only, as it is corrupt.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 36 insertions, 2 deletions

diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index b6ba292e9544..e6f207eebab4 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -181,6 +181,12 @@ static int ocfs2_extent_map_find_leaf(struct inode *inode,
                         ret = -EBADR;
                         if (rec_end > OCFS2_I(inode)->ip_clusters) {
                                 mlog_errno(ret);
+                                ocfs2_error(inode->i_sb,
+                                            "Extent %d at e_blkno %"MLFu64" of inode %"MLFu64" goes past ip_clusters of %u\n",
+                                            i,
+                                            le64_to_cpu(rec->e_blkno),
+                                            OCFS2_I(inode)->ip_blkno,
+                                            OCFS2_I(inode)->ip_clusters);
                                 goto out_free;
                         }
 
@@ -226,6 +232,12 @@ static int ocfs2_extent_map_find_leaf(struct inode *inode,
                         ret = -EBADR;
                         if (blkno) {
                                 mlog_errno(ret);
+                                ocfs2_error(inode->i_sb,
+                                            "Multiple extents for (cpos = %u, clusters = %u) on inode %"MLFu64"; e_blkno %"MLFu64" and rec %d at e_blkno %"MLFu64"\n",
+                                            cpos, clusters,
+                                            OCFS2_I(inode)->ip_blkno,
+                                            blkno, i,
+                                            le64_to_cpu(rec->e_blkno));
                                 goto out_free;
                         }
 
@@ -238,6 +250,10 @@ static int ocfs2_extent_map_find_leaf(struct inode *inode,
                  */
                 ret = -EBADR;
                 if (!blkno) {
+                        ocfs2_error(inode->i_sb,
+                                    "No record found for (cpos = %u, clusters = %u) on inode %"MLFu64"\n",
+                                    cpos, clusters,
+                                    OCFS2_I(inode)->ip_blkno);
                         mlog_errno(ret);
                         goto out_free;
                 }
@@ -266,6 +282,20 @@ static int ocfs2_extent_map_find_leaf(struct inode *inode,
 
         for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
                 rec = &el->l_recs[i];
+
+                if ((le32_to_cpu(rec->e_cpos) + le32_to_cpu(rec->e_clusters)) >
+                    OCFS2_I(inode)->ip_clusters) {
+                        ret = -EBADR;
+                        mlog_errno(ret);
+                        ocfs2_error(inode->i_sb,
+                                    "Extent %d at e_blkno %"MLFu64" of inode %"MLFu64" goes past ip_clusters of %u\n",
+                                    i,
+                                    le64_to_cpu(rec->e_blkno),
+                                    OCFS2_I(inode)->ip_blkno,
+                                    OCFS2_I(inode)->ip_clusters);
+                        return ret;
+                }
+
                 ret = ocfs2_extent_map_insert(inode, rec,
                                               le16_to_cpu(el->l_tree_depth));
                 if (ret) {
@@ -526,6 +556,10 @@ static int ocfs2_extent_map_insert(struct inode *inode,
                     OCFS2_I(inode)->ip_map.em_clusters) {
                         ret = -EBADR;
                         mlog_errno(ret);
+                        ocfs2_error(inode->i_sb,
+                                    "Zero e_clusters on non-tail extent record at e_blkno %"MLFu64" on inode %"MLFu64"\n",
+                                    le64_to_cpu(rec->e_blkno),
+                                    OCFS2_I(inode)->ip_blkno);
                         return ret;
                 }
 
@@ -588,12 +622,12 @@ static int ocfs2_extent_map_insert(struct inode *inode,
  * Existing record in the extent map:
  *
  *      cpos = 10, len = 10
- *      |---------|
+ *      |---------|
  *
  * New Record:
  *
  *      cpos = 10, len = 20
- *      |------------------|
+ *      |------------------|
  *
  * The passed record is the new on-disk record.  The new_clusters value
  * is how many clusters were added to the file.  If the append is a