On Wed, Apr 19, 2023 at 7:59 AM Leon Romanovsky <leon@xxxxxxxxxx> wrote:
>
> On Tue, Apr 18, 2023 at 02:43:02PM -0600, David Ahern wrote:
> > On 4/18/23 10:41 AM, Leon Romanovsky wrote:
> > > Hi,
> > >
> > > I came to the following diff which eliminates the kernel panics,
> > > unfortunately I can explain only second hunk, but first is required
> > > too.
> > >
> > > diff --git a/net/core/dst.c b/net/core/dst.c
> > > index 3247e84045ca..750c8edfe29a 100644
> > > --- a/net/core/dst.c
> > > +++ b/net/core/dst.c
> > > @@ -72,6 +72,8 @@ void dst_init(struct dst_entry *dst, struct dst_ops *ops,
> > > dst->flags = flags;
> > > if (!(flags & DST_NOCOUNT))
> > > dst_entries_add(ops, 1);
> > > +
> > > + INIT_LIST_HEAD(&dst->rt_uncached);
> >
> > d288a162dd1c73507da582966f17dd226e34a0c0 moved rt_uncached from rt6_info
> > and rtable to dst_entry. Only ipv4 and ipv6 usages initialize it. Since
> > it is now in dst_entry, dst_init is the better place so it can be
> > removed from rt_dst_alloc and rt6_info_init.
>
> This is why I placed it there, but the rt_uncached list is initialized
> in xfrm6 right before first call to rt6_uncached_list_add().
>
> 70 static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
> 71 const struct flowi *fl)
> 72 {
> ...
> 92 INIT_LIST_HEAD(&xdst->u.rt6.dst.rt_uncached);
> 93 rt6_uncached_list_add(&xdst->u.rt6);
>
> My silly explanation is that xfrm6_dst_destroy() can be called before xfrm6_fill_dst().
>
> Thanks
>
> >
Please take a look at the fix that was sent yesterday :
https://patchwork.kernel.org/project/netdevbpf/patch/20230418165426.1869051-1-mbizon@xxxxxxxxxx/
Thanks.
