diff options
| author | Florian Westphal <fw@strlen.de> | 2018-05-27 11:20:48 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2018-05-29 14:50:26 +0200 |
| commit | eb1fb1479b710b0c1675986a41bea1022091c2a3 (patch) | |
| tree | 10866a68f0f6e47a78ab9a7f463f3edebc3d2ad9 /net/netfilter | |
| parent | 88491c11b0fd66881becc418d9db52462ae41870 (diff) | |
| download | op-kernel-dev-eb1fb1479b710b0c1675986a41bea1022091c2a3.zip op-kernel-dev-eb1fb1479b710b0c1675986a41bea1022091c2a3.tar.gz | |
netfilter: nft_compat: use call_rcu for nfnl_compat_get
Just use .call_rcu instead. We can drop the rcu read lock
after obtaining a reference and re-acquire on return.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nft_compat.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c index 1d99a1ef..8d1ff65 100644 --- a/net/netfilter/nft_compat.c +++ b/net/netfilter/nft_compat.c @@ -611,10 +611,10 @@ nla_put_failure: return -1; } -static int nfnl_compat_get(struct net *net, struct sock *nfnl, - struct sk_buff *skb, const struct nlmsghdr *nlh, - const struct nlattr * const tb[], - struct netlink_ext_ack *extack) +static int nfnl_compat_get_rcu(struct net *net, struct sock *nfnl, + struct sk_buff *skb, const struct nlmsghdr *nlh, + const struct nlattr * const tb[], + struct netlink_ext_ack *extack) { int ret = 0, target; struct nfgenmsg *nfmsg; @@ -653,16 +653,21 @@ static int nfnl_compat_get(struct net *net, struct sock *nfnl, return -EINVAL; } + if (!try_module_get(THIS_MODULE)) + return -EINVAL; + + rcu_read_unlock(); try_then_request_module(xt_find_revision(nfmsg->nfgen_family, name, rev, target, &ret), fmt, name); - if (ret < 0) - return ret; + goto out_put; skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); - if (skb2 == NULL) - return -ENOMEM; + if (skb2 == NULL) { + ret = -ENOMEM; + goto out_put; + } /* include the best revision for this extension in the message */ if (nfnl_compat_fill_info(skb2, NETLINK_CB(skb).portid, @@ -672,14 +677,16 @@ static int nfnl_compat_get(struct net *net, struct sock *nfnl, nfmsg->nfgen_family, name, ret, target) <= 0) { kfree_skb(skb2); - return -ENOSPC; + goto out_put; } ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); if (ret > 0) ret = 0; - +out_put: + rcu_read_lock(); + module_put(THIS_MODULE); return ret == -EAGAIN ? -ENOBUFS : ret; } @@ -691,7 +698,7 @@ static const struct nla_policy nfnl_compat_policy_get[NFTA_COMPAT_MAX+1] = { }; static const struct nfnl_callback nfnl_nft_compat_cb[NFNL_MSG_COMPAT_MAX] = { - [NFNL_MSG_COMPAT_GET] = { .call = nfnl_compat_get, + [NFNL_MSG_COMPAT_GET] = { .call_rcu = nfnl_compat_get_rcu, .attr_count = NFTA_COMPAT_MAX, .policy = nfnl_compat_policy_get }, }; |
