ldiskfs/kernel_patches/patches/ext3-block-bitmap-validation-2.6-rhel5.patch

   1 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
   2 Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
   3 Index: linux-2.6.18-8.1.8/fs/ext3/balloc.c
   4 ===================================================================
   5 --- linux-2.6.18-8.1.8.orig/fs/ext3/balloc.c
   6 +++ linux-2.6.18-8.1.8/fs/ext3/balloc.c
   7 @@ -143,6 +143,14 @@ unsigned ext3_init_block_bitmap(struct s
   8         return free_blocks - sbi->s_itb_per_group - 2;
   9  }
  10
  11 +static inline int
  12 +block_in_use(unsigned long block, struct super_block *sb, unsigned char *map)
  13 +{
  14 +       return ext3_test_bit ((block -
  15 +               le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block)) %
  16 +                       EXT3_BLOCKS_PER_GROUP(sb), map);
  17 +}
  18 +
  19  /*
  20   * Read the bitmap for a given block_group, reading into the specified
  21   * slot in the superblock's bitmap cache.
  22 @@ -152,14 +160,18 @@ unsigned ext3_init_block_bitmap(struct s
  23  struct buffer_head *
  24  read_block_bitmap(struct super_block *sb, unsigned int block_group)
  25  {
  26 +       int i;
  27         struct ext3_group_desc * desc;
  28         struct buffer_head * bh = NULL;
  29 +       unsigned long bitmap_blk;
  30
  31         desc = ext3_get_group_desc (sb, block_group, NULL);
  32         if (!desc)
  33 -               goto error_out;
  34 +               return NULL;
  35 +
  36 +       bitmap_blk = le32_to_cpu(desc->bg_block_bitmap);
  37         if (desc->bg_flags & cpu_to_le16(EXT3_BG_BLOCK_UNINIT)) {
  38 -               bh = sb_getblk(sb, le32_to_cpu(desc->bg_block_bitmap));
  39 +               bh = sb_getblk(sb, bitmap_blk);
  40                 if (!buffer_uptodate(bh)) {
  41                         lock_buffer(bh);
  42                         if (!buffer_uptodate(bh)) {
  43 @@ -169,15 +181,44 @@ read_block_bitmap(struct super_block *sb
  44                         unlock_buffer(bh);
  45                 }
  46         } else {
  47 -               bh = sb_bread(sb, le32_to_cpu(desc->bg_block_bitmap));
  48 +               bh = sb_bread(sb, bitmap_blk);
  49         }
  50         if (!bh)
  51 -               ext3_error (sb, "read_block_bitmap",
  52 +               ext3_error (sb, __FUNCTION__,
  53                             "Cannot read block bitmap - "
  54 -                           "block_group = %d, block_bitmap = %u",
  55 -                           block_group, le32_to_cpu(desc->bg_block_bitmap));
  56 -error_out:
  57 +                           "block_group = %d, block_bitmap = %lu",
  58 +                           block_group, bitmap_blk);
  59 +
  60 +       /* check whether block bitmap block number is set */
  61 +       if (!block_in_use(bitmap_blk, sb, bh->b_data)) {
  62 +               /* bad block bitmap */
  63 +               goto error_out;
  64 +       }
  65 +
  66 +       /* check whether the inode bitmap block number is set */
  67 +       bitmap_blk = le32_to_cpu(desc->bg_inode_bitmap);
  68 +       if (!block_in_use(bitmap_blk, sb, bh->b_data)) {
  69 +       /* bad block bitmap */
  70 +               goto error_out;
  71 +       }
  72 +       /* check whether the inode table block number is set */
  73 +       bitmap_blk = le32_to_cpu(desc->bg_inode_table);
  74 +       for (i = 0; i < EXT3_SB(sb)->s_itb_per_group; i++, bitmap_blk++) {
  75 +               if (!block_in_use(bitmap_blk, sb, bh->b_data)) {
  76 +                       /* bad block bitmap */
  77 +                       goto error_out;
  78 +               }
  79 +       }
  80         return bh;
  81 +
  82 +error_out:
  83 +       brelse(bh);
  84 +       ext3_error(sb, __FUNCTION__,
  85 +                       "Invalid block bitmap - "
  86 +                       "block_group = %d, block = %lu",
  87 +                       block_group, bitmap_blk);
  88 +       return NULL;
  89 +
  90  }
  91  /*
  92   * The reservation window structure operations
  93 @@ -1617,14 +1658,6 @@ ext3_fsblk_t ext3_count_free_blocks(stru
  94  #endif
  95  }
  96
  97 -static inline int
  98 -block_in_use(ext3_fsblk_t block, struct super_block *sb, unsigned char *map)
  99 -{
 100 -       return ext3_test_bit ((block -
 101 -               le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block)) %
 102 -                        EXT3_BLOCKS_PER_GROUP(sb), map);
 103 -}
 104 -
 105  static inline int test_root(int a, int b)
 106  {
 107         int num = b;