2012-05-31 18:32:03

by Aditya Kali

Subject: [PATCH] libext2fs: fix i_blocks for extent leaf create/delete

When libext2fs allocates/deletes an extent leaf, the i_blocks
value is incremented/decremented by fs->blocksize / 512. This
is incorrect in case of bigalloc. The correct way here is to
use cluster_size / 512.
The problem is seen if we try to create a large inode using
libext2fs (say using ext2fs_block_iterate3()) on a bigalloc
filesystem. fsck catches this and complains.

Signed-off-by: Aditya Kali <[email protected]>
---
lib/ext2fs/extent.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/ext2fs/extent.c b/lib/ext2fs/extent.c
index eb096d6..8828764 100644
--- a/lib/ext2fs/extent.c
+++ b/lib/ext2fs/extent.c
@@ -1027,7 +1027,8 @@ static errcode_t extent_node_split(ext2_extent_handle_t handle)
goto done;

/* new node hooked in, so update inode block count (do this here?) */
- handle->inode->i_blocks += handle->fs->blocksize / 512;
+ handle->inode->i_blocks += (handle->fs->blocksize *
+ EXT2FS_CLUSTER_RATIO(handle->fs)) / 512;
retval = ext2fs_write_inode(handle->fs, handle->ino,
handle->inode);
if (retval)
@@ -1501,7 +1502,9 @@ errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags)
return retval;

retval = ext2fs_extent_delete(handle, flags);
- handle->inode->i_blocks -= handle->fs->blocksize / 512;
+ handle->inode->i_blocks -=
+ (handle->fs->blocksize *
+ EXT2FS_CLUSTER_RATIO(handle->fs)) / 512;
retval = ext2fs_write_inode(handle->fs, handle->ino,
handle->inode);
ext2fs_block_alloc_stats2(handle->fs,
--
1.7.7.3

2012-06-11 03:53:03

by Theodore Ts'o

Subject: Re: [PATCH] libext2fs: fix i_blocks for extent leaf create/delete

On Thu, May 31, 2012 at 11:31:58AM -0700, Aditya Kali wrote:
> When libext2fs allocates/deletes an extent leaf, the i_blocks
> value is incremented/decremented by fs->blocksize / 512. This
> is incorrect in case of bigalloc. The correct way here is to
> use cluster_size / 512.
> The problem is seen if we try to create a large inode using
> libext2fs (say using ext2fs_block_iterate3()) on a bigalloc
> filesystem. fsck catches this and complains.
>
> Signed-off-by: Aditya Kali <[email protected]>

Applied, thanks.

- Ted