ext4-fix-fs-corruption-with-delalloc.patch

   1 ext4: Fix filesystem corruption on FS mounted with delalloc
   2
   3 From: Valerie Clement <valerie.clement@bull.net>
   4
   5 This patch fixes a filesystem corruption issue when the filesystem is
   6 mounted with the delalloc option and blocksize < pagesize.
   7
   8 In the  mpage_put_bnr_to_bhs() function, when skipping the first blocks
   9 at the beginning of the first page, pblock should not be incremented,
  10 otherwise the last blocks are corrupted. When writing into blocks at the
  11 end of a group, the first blocks of the following group can be corrupted.
  12 In that case, we've got the error message below:
  13 EXT4-fs error (device sdc1): ext4_valid_block_bitmap: Invalid block bitmap -
  14 block_group = 6233, block = 51060737
  15
  16 (Issue found when using fsstress tool on ext4 FS with 1K blocksize)
  17
  18 Signed-off-by: Valerie Clement <valerie.clement@bull.net>
  19 Signed-off-by: Mingming Cao <cmm@us.ibm.com>
  20
  21 ---
  22  fs/mpage.c |    1 -
  23  1 file changed, 1 deletion(-)
  24
  25 Index: linux-2.6.26-rc4/fs/mpage.c
  26 ===================================================================
  27 --- linux-2.6.26-rc4.orig/fs/mpage.c    2008-05-29 10:52:38.000000000 -0700
  28 +++ linux-2.6.26-rc4/fs/mpage.c 2008-05-29 10:52:39.000000000 -0700
  29 @@ -844,7 +844,6 @@ static void mpage_put_bnr_to_bhs(struct
  30                                 if (cur_logical >= logical)
  31                                         break;
  32                                 cur_logical++;
  33 -                               pblock++;
  34                         } while ((bh = bh->b_this_page) != head);
  35
  36                         do {