We will convert ip6mr_rtm_getroute() to RCU in the following patch, where __ip6mr_get_table() will be called under RCU. nlmsg_new() uses GFP_KERNEL and needs to be called before holding rcu_read_lock(). As a prep, let's move nlmsg_new() before __ip6mr_get_table(). Signed-off-by: Kuniyuki Iwashima --- net/ipv6/ip6mr.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c index 7ea572db9075..5356957bfe94 100644 --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -2702,6 +2702,10 @@ static int ip6mr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, if (err < 0) return err; + skb = nlmsg_new(mr6_msgsize(false), GFP_KERNEL); + if (!skb) + return -ENOBUFS; + if (tb[RTA_SRC]) src = nla_get_in6_addr(tb[RTA_SRC]); if (tb[RTA_DST]) @@ -2711,7 +2715,8 @@ static int ip6mr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, mrt = __ip6mr_get_table(net, tableid ?: RT_TABLE_DEFAULT); if (!mrt) { NL_SET_ERR_MSG_MOD(extack, "MR table does not exist"); - return -ENOENT; + err = -ENOENT; + goto err; } /* entries are added/deleted only under RTNL */ @@ -2720,21 +2725,20 @@ static int ip6mr_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, rcu_read_unlock(); if (!cache) { NL_SET_ERR_MSG_MOD(extack, "MR cache entry not found"); - return -ENOENT; + err = -ENOENT; + goto err; } - skb = nlmsg_new(mr6_msgsize(false), GFP_KERNEL); - if (!skb) - return -ENOBUFS; - err = ip6mr_fill_mroute(mrt, skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, cache, RTM_NEWROUTE, 0); - if (err < 0) { - kfree_skb(skb); - return err; - } + if (err < 0) + goto err; return rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); + +err: + kfree_skb(skb); + return err; } static int ip6mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb) -- 2.53.0.1213.gd9a14994de-goog