Re: [Ext2-devel] [PATCH] 2/6 Detect overflows in loop counters

Re: [Ext2-devel] [PATCH] 2/6 Detect overflows in loop counters

[Theodore Tso]

First post!  (Note new mailing list)

On Wed, Aug 30, 2006 at 01:18:21PM -0500, Eric Sandeen wrote:
> I've respun & refactored the remaining patches against the mercurial 
> repo, and put changelog entries in...

Thanks, I appreciate it!  

					- Ted

Comments on respun 16T patches: group_desc_loops

[Theodore Tso]

On Wed, Aug 30, 2006 at 01:18:21PM -0500, Eric Sandeen wrote:
> http://people.redhat.com/esandeen/ext3/e2fsprogs-1.39-16T/e2fsprogs-hg-20060830-16T-patches.tar.gz

In the group_desc_loops patches in the above tarball:

>For loops iterating over all group descriptors, consistently define
>first_block and last_block in a way that they are inclusive of the
>range, and do not overflow.
>
>Previously on the last block group we did a test of <= first + dec_blocks;
>this would actually wrap back to 0 for a total block count of 2^32-1

As far as I can tell this is not a problem.  sb->s_last_block can be
at most 2**32-1 --- which means that the last valid block number is
actually 2**32-2, since block numbers are zero based.

So as long as the handling of the last block group is correct, I don't
think we actually need to make the <= to < change.  It's not wrong to
make the change, just not necessary as far as I can see.  
Also, there are some files for which the only change was variable
names.  That's fine, but the changelogs should state that.

So there is a last block group handling bug in ext2fs_check_desc(),
but I didn't see any other bugs that this patch would actually affect.
Am I missing anything?

Regards,

						- Ted

Re: [Ext2-devel] [PATCH] 2/6 Detect overflows in loop counters

[Theodore Tso]

On Wed, Aug 30, 2006 at 01:18:21PM -0500, Eric Sandeen wrote:
> new patchset & series is at
> 
> http://people.redhat.com/esandeen/ext3/e2fsprogs-1.39-16T/e2fsprogs-hg-20060830-16T-patches.tar.gz

I've applied your patches (with a few minor changes in the
ChangeLogs), and committed them into Mercurial.

Regards,

						- Ted

Re: [Ext2-devel] [PATCH] 2/6 Detect overflows in loop counters

[Eric Sandeen]

Theodore Tso wrote:
> On Wed, Aug 30, 2006 at 01:18:21PM -0500, Eric Sandeen wrote:
>> new patchset & series is at
>>
>> http://people.redhat.com/esandeen/ext3/e2fsprogs-1.39-16T/e2fsprogs-hg-20060830-16T-patches.tar.gz
> 
> I've applied your patches (with a few minor changes in the
> ChangeLogs), and committed them into Mercurial.
> 
> Regards,
> 
> 						- Ted

Thanks Ted!

There's one more lurking out there that I somehow neglected to put in 
the above patchset, sent 08/16/2006, [Ext2-devel] [PATCH] fix size 
calculation when mkfs is pointed at a regular file

http://article.gmane.org/gmane.comp.file-systems.ext2.devel/4703

Thanks,

-Eric