Re: [PATCH 20/20] xfrm: iptfs: only publish mode_data after clone setup

[Steffen Klassert <steffen.klassert@secunet.com>]

On Tue, Mar 24, 2026 at 12:33:15PM +0100, Paolo Abeni wrote:
> On 3/23/26 9:34 AM, Steffen Klassert wrote:
> > From: Paul Moses <p@1g4.org>
> > 
> > iptfs_clone_state() stores x->mode_data before allocating the reorder
> > window. If that allocation fails, the code frees the cloned state and
> > returns -ENOMEM, leaving x->mode_data pointing at freed memory.
> > 
> > The xfrm clone unwind later runs destroy_state() through x->mode_data,
> > so the failed clone path tears down IPTFS state that clone_state()
> > already freed.
> > 
> > Keep the cloned IPTFS state private until all allocations succeed so
> > failed clones leave x->mode_data unset. The destroy path already
> > handles a NULL mode_data pointer.
> > 
> > Fixes: 6be02e3e4f37 ("xfrm: iptfs: handle reordering of received packets")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Paul Moses <p@1g4.org>
> > Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
> 
> While applying this series to verify the PR, I get the following error:
> 
> Applying: xfrm: iptfs: only publish mode_data after clone setup
> error: sha1 information is lacking or useless (net/xfrm/xfrm_iptfs.c).
> error: could not build fake ancestor
> Patch failed at 0020 xfrm: iptfs: only publish mode_data after clone setup
> 
> The above also prevents the CI from testing the series. Steffen, could
> you please have a look? Possibly a repost could be needed.

I guess this is due to a merge conflict with:

69050f8d6d07 ("treewide: Replace kmalloc with kmalloc_obj for non-scalar types")

Repost will not help in that case. Not sure what to do
here. The only thing that would fix it is a forced rebase
of the ipsec tree onto the net tree.