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>> tableid = tb[RTA_TABLE] ? nla_get_u32(tb[RTA_TABLE]) : 0; >> >> + rcu_read_lock(); > > AFAICS ip6mr_rtm_getroute() runs with RTNL held, so I don't see > why this patch is needed. That's true, but it's called neither with RCU nor RTNL lock when RTNL_FLAG_DOIT_UNLOCKED is set in rtnetlink_rcv_msg(): > if (flags & RTNL_FLAG_DOIT_UNLOCKED) { > doit = link->doit; > rcu_read_unlock(); > if (doit) > err = doit(skb, nlh, extack); > module_put(owner); > return err; > } > rcu_read_unlock(); I realized now that I completely misunderstood how ip6mr_rtm_dumproute() gets called - it should be still safe though because mpls_netconf_dump_devconf() and getaddr_dumpit() hold the RCU lock while mpls_dump_routes() asserts that the RTNL lock is held. Is that observation correct?