Hi, On Wed, Jun 06, 2018 at 01:53:39PM -0400, David Miller wrote: > From: Alexander Aring <ar...@mojatatu.com> > Date: Tue, 5 Jun 2018 18:04:04 -0400 > > > This patch adds care about tailroom length for allocate a skb from ipv6 > > level stack. In case of 6lowpan we had the problem the skb runs into a > > skb_over_panic() in some special length cases. The root was there was no > > tailroom allocated for the IEEE 802.15.4 checksum, although we had > > the necessary tailroom specified inside the netdev structure. > > > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195059 > > Reported-by: David Palma <david.pa...@ntnu.no> > > Reported-by: Rabi Narayan Sahoo <rabinarayans0...@gmail.com> > > Signed-off-by: Alexander Aring <ar...@mojatatu.com> > > needed_tailroom is an optimization to avoid SKB reallocations > and adjustments, it is not a guarantee. >
okay, then you want to have this patch for net-next? As an optimization? Of course, when it's open again. > If you are seeing crashes, it means code is assuming something which > is not to be assumed. > > Whatever code is involved, it needs to check that the necessary > tailroom is there and reallocate if necessary, rather than > blindly pushing past the end of the SKB data. > I see, I will add checks and reallocs (if necessary) in the underlaying subsystem level. Thanks for clarifying this. - Alex
