Re: [PATCH 3/3] e2fsck: make sure the extent tree is consistent after bogus node in the tree

[Eric Sandeen <sandeen@redhat.com>]

On 12/20/12 5:43 PM, Theodore Ts'o wrote:
> Commit 789bd401c3 ("e2fsck: fix incorrect interior node logical start
> values") surfaced a bug where if e2fsck finds and removed an invalid
> node in the extent tree, i.e.:
> 
> Inode 12 has an invalid extent node (blk 22, lblk 0)
> Clear? yes
> 
> It was possible for starting logical blocks found in the interior
> nodes of the extent tree.  Commit 789bd401c3 added the ability for
> e2fsck to discover this problem, which resulted in the test
> f_extent_bad_node to fail when the second pass of e2fsck reported the
> following complaint:
> 
> Interior extent node level 0 of inode 12:
> Logical start 0 does not match logical start 3 at next level.  Fix? yes
> 
> This patch fixes this by adding a call to ext2fs_extent_fix_parents()
> after deleting the bogus node in the extent tree.
> 
> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>


Reviewed-by: Eric Sandeen <sandeen@redhat.com>

Thanks Ted, sorry I didn't catch this.  And this gives me hope
that maybe the extent tree corruption report I had received
might be due to an e2fsck, not kernel runtime...

-Eric

> ---
>  e2fsck/pass1.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
> index 2acbb53..a8231f4 100644
> --- a/e2fsck/pass1.c
> +++ b/e2fsck/pass1.c
> @@ -1809,6 +1809,7 @@ report_problem:
>  					pctx->str = "ext2fs_extent_delete";
>  					return;
>  				}
> +				ext2fs_extent_fix_parents(ehandle);
>  				pctx->errcode = ext2fs_extent_get(ehandle,
>  								  EXT2_EXTENT_CURRENT,
>  								  &extent);
>