This is a note to let you know that I've just added the patch titled gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: gro-remove-rcu_read_lock-rcu_read_unlock-from-gro_co.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 076c19654c7df250f75b4e024f4870127434f561 Author: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Tue Nov 23 14:56:08 2021 -0800 gro: remove rcu_read_lock/rcu_read_unlock from gro_complete handlers [ Upstream commit 627b94f75b82d13d1530b59155a545fd99d807db ] All gro_complete() handlers are called from napi_gro_complete() while rcu_read_lock() has been called. There is no point stacking more rcu_read_lock() Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Stable-dep-of: 7e4196935069 ("fou: Fix null-ptr-deref in GRO.") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 17989688f54b..08b479f04ed0 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -556,13 +556,10 @@ static int geneve_gro_complete(struct sock *sk, struct sk_buff *skb, gh_len = geneve_hlen(gh); type = gh->proto_type; - rcu_read_lock(); ptype = gro_find_complete_by_type(type); if (ptype) err = ptype->callbacks.gro_complete(skb, nhoff + gh_len); - rcu_read_unlock(); - skb_set_inner_mac_header(skb, nhoff + gh_len); return err; diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c index ff0d3fc82c0f..c96ff4a1d4a0 100644 --- a/net/8021q/vlan_core.c +++ b/net/8021q/vlan_core.c @@ -516,12 +516,10 @@ static int vlan_gro_complete(struct sk_buff *skb, int nhoff) struct packet_offload *ptype; int err = -ENOENT; - rcu_read_lock(); ptype = gro_find_complete_by_type(type); if (ptype) err = ptype->callbacks.gro_complete(skb, nhoff + sizeof(*vhdr)); - rcu_read_unlock(); return err; } diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 2b0eb24199d6..081390c32707 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -457,13 +457,11 @@ int eth_gro_complete(struct sk_buff *skb, int nhoff) if (skb->encapsulation) skb_set_inner_mac_header(skb, nhoff); - rcu_read_lock(); ptype = gro_find_complete_by_type(type); if (ptype != NULL) err = ptype->callbacks.gro_complete(skb, nhoff + sizeof(struct ethhdr)); - rcu_read_unlock(); return err; } EXPORT_SYMBOL(eth_gro_complete); diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index cac63bb20c16..58dfca09093c 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1634,10 +1634,9 @@ int inet_gro_complete(struct sk_buff *skb, int nhoff) csum_replace2(&iph->check, iph->tot_len, newlen); iph->tot_len = newlen; - rcu_read_lock(); ops = rcu_dereference(inet_offloads[proto]); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) - goto out_unlock; + goto out; /* Only need to add sizeof(*iph) to get to the next hdr below * because any hdr with option will have been flushed in @@ -1647,9 +1646,7 @@ int inet_gro_complete(struct sk_buff *skb, int nhoff) tcp4_gro_complete, udp4_gro_complete, skb, nhoff + sizeof(*iph)); -out_unlock: - rcu_read_unlock(); - +out: return err; } EXPORT_SYMBOL(inet_gro_complete); diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index 5aacc75e495c..605d9673d6ec 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -265,19 +265,16 @@ static int fou_gro_complete(struct sock *sk, struct sk_buff *skb, const struct net_offload *ops; int err = -ENOSYS; - rcu_read_lock(); offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) - goto out_unlock; + goto out; err = ops->callbacks.gro_complete(skb, nhoff); skb_set_inner_mac_header(skb, nhoff); -out_unlock: - rcu_read_unlock(); - +out: return err; } @@ -479,18 +476,16 @@ static int gue_gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff) return err; } - rcu_read_lock(); offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) - goto out_unlock; + goto out; err = ops->callbacks.gro_complete(skb, nhoff + guehlen); skb_set_inner_mac_header(skb, nhoff + guehlen); -out_unlock: - rcu_read_unlock(); +out: return err; } diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index e9dabf1affe9..b4da692b9734 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -248,13 +248,10 @@ static int gre_gro_complete(struct sk_buff *skb, int nhoff) if (greh->flags & GRE_CSUM) grehlen += GRE_HEADER_SECTION; - rcu_read_lock(); ptype = gro_find_complete_by_type(type); if (ptype) err = ptype->callbacks.gro_complete(skb, nhoff + grehlen); - rcu_read_unlock(); - skb_set_inner_mac_header(skb, nhoff + grehlen); return err; diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 418da7a8a075..6e36eb1ba276 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -645,7 +645,6 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff, uh->len = newlen; - rcu_read_lock(); sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb, udp4_lib_lookup_skb, skb, uh->source, uh->dest); if (sk && udp_sk(sk)->gro_complete) { @@ -661,7 +660,6 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff, } else { err = udp_gro_complete_segment(skb); } - rcu_read_unlock(); if (skb->remcsum_offload) skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM; diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index f67921e0dd56..673f02ea62aa 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -328,18 +328,14 @@ INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff) iph->payload_len = htons(skb->len - nhoff - sizeof(*iph)); - rcu_read_lock(); - nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); if (WARN_ON(!ops || !ops->callbacks.gro_complete)) - goto out_unlock; + goto out; err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete, udp6_gro_complete, skb, nhoff); -out_unlock: - rcu_read_unlock(); - +out: return err; }