ext4: calculate and verify checksums for inode bitmaps

[pandora-kernel.git] / fs / ext4 / ialloc.c

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index 8207dfa..fb897ec 100644 (file)
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -82,12 +82,17 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb,
                ext4_free_inodes_set(sb, gdp, 0);
                ext4_itable_unused_set(sb, gdp, 0);
                memset(bh->b_data, 0xff, sb->s_blocksize);
+               ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh,
+                                          EXT4_INODES_PER_GROUP(sb) / 8);
                return 0;
        }
 
        memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8);
        ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8,
                        bh->b_data);
+       ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh,
+                                  EXT4_INODES_PER_GROUP(sb) / 8);
+       gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp);
 
        return EXT4_INODES_PER_GROUP(sb);
 }
@@ -128,12 +133,12 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
                return NULL;
        }
        if (bitmap_uptodate(bh))
-               return bh;
+               goto verify;
 
        lock_buffer(bh);
        if (bitmap_uptodate(bh)) {
                unlock_buffer(bh);
-               return bh;
+               goto verify;
        }
 
        ext4_lock_group(sb, block_group);
@@ -141,6 +146,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
                ext4_init_inode_bitmap(sb, bh, block_group, desc);
                set_bitmap_uptodate(bh);
                set_buffer_uptodate(bh);
+               set_buffer_verified(bh);
                ext4_unlock_group(sb, block_group);
                unlock_buffer(bh);
                return bh;
@@ -154,7 +160,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
                 */
                set_bitmap_uptodate(bh);
                unlock_buffer(bh);
-               return bh;
+               goto verify;
        }
        /*
         * submit the buffer_head for reading
@@ -171,6 +177,20 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group)
                           block_group, bitmap_blk);
                return NULL;
        }
+
+verify:
+       ext4_lock_group(sb, block_group);
+       if (!buffer_verified(bh) &&
+           !ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh,
+                                          EXT4_INODES_PER_GROUP(sb) / 8)) {
+               ext4_unlock_group(sb, block_group);
+               put_bh(bh);
+               ext4_error(sb, "Corrupt inode bitmap - block_group = %u, "
+                          "inode_bitmap = %llu", block_group, bitmap_blk);
+               return NULL;
+       }
+       ext4_unlock_group(sb, block_group);
+       set_buffer_verified(bh);
        return bh;
 }
 
@@ -276,6 +296,8 @@ void ext4_free_inode(handle_t *handle, struct inode *inode)
                ext4_used_dirs_set(sb, gdp, count);
                percpu_counter_dec(&sbi->s_dirs_counter);
        }
+       ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh,
+                                  EXT4_INODES_PER_GROUP(sb) / 8);
        gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp);
        ext4_unlock_group(sb, block_group);
 
@@ -751,7 +773,7 @@ got:
                goto fail;
 
        /* Update the relevant bg descriptor fields */
-       if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
+       if (ext4_has_group_desc_csum(sb)) {
                int free;
                struct ext4_group_info *grp = ext4_get_group_info(sb, group);
 
@@ -782,7 +804,9 @@ got:
                        atomic_inc(&sbi->s_flex_groups[f].used_dirs);
                }
        }
-       if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
+       if (ext4_has_group_desc_csum(sb)) {
+               ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh,
+                                          EXT4_INODES_PER_GROUP(sb) / 8);
                gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
                ext4_unlock_group(sb, group);
        }