On Tue, Aug 4, 2020 at 10:23 PM Martin Schiller <m...@dev.tdt.de> wrote: > > > Adding skb_cow before these skb_push calls would indeed help > > preventing kernel panics, but that might not be the essential issue > > here, and it might also prevent us from discovering the real issue. (I > > guess this is also the reason skb_cow is not included in skb_push > > itself.) > > Well, you are right that the panic is "useful" to discover the real > problem. But on the other hand, if it is possible to prevent a panic, I > think we should do so. Maybe with adding a warning, when skb_cow() needs > to reallocate memory. > > But this is getting a little bit off topic. For this patch I can say: > > LGTM. > > Reviewed-by: Martin Schiller <m...@dev.tdt.de>
Thank you so much! Yes, it might be better to use skb_cow with a warning so that we can prevent kernel panic while still being able to discover the problem. If we want to do this, there are 2 more places in addition to lapbeth_data_transmit that need to be guarded with skb_cow: lapb_send_iframe and lapb_transmit_buffer in net/lapb/lapb_out.c. Maybe we can address this in a separate patch.
