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As you have already explained, we can ignore the ip6mr_vif_seq_start() error path, so the issue boils down to ip6mr_get_table() being called without entering a RCU read-side critical section from these 4 functions: ipmr_vif_seq_start(), ip6mr_ioctl(), ip6mr_compat_ioctl() and ip6mr_get_route(). It is my understanding that in none of these four cases the RTNL lock is held either; at least according to the RCU-lockdep splat we clearly see that this is not the case in ip6mr_ioctl() – but please correct me if I'm wrong. > Note that net/ipv4/ipmr.c would have a similar issue. Yes, looks indeed like that :-/ > Please split your patch in small units, their Fixes: tags are likely > different, and if some code breaks something, > fixing the issue will be easier. > > The changelog seemed to only address the first ip6mr_vif_seq_start() part. If you prefer that I can split the change into 4 commits addressing each of the 4 functions mentioned before. Kind regards, Stefan