Commit 779b7931 authored by Daniel Axtens's avatar Daniel Axtens Committed by David S. Miller
Browse files

net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len 



If you take a GSO skb, and split it into packets, will the network
length (L3 headers + L4 headers + payload) of those packets be small
enough to fit within a given MTU?

skb_gso_validate_mtu gives you the answer to that question. However,
we recently added to add a way to validate the MAC length of a split GSO
skb (L2+L3+L4+payload), and the names get confusing, so rename
skb_gso_validate_mtu to skb_gso_validate_network_len

Signed-off-by: default avatarDaniel Axtens <dja@axtens.net>
Reviewed-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4e00f5d5

include/linux/skbuff.h

+1 −1
Original line number Diff line number Diff line
@@ -3286,7 +3286,7 @@ void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); 
int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen);

void skb_scrub_packet(struct sk_buff *skb, bool xnet);

unsigned int skb_gso_transport_seglen(const struct sk_buff *skb);

bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu);

bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu);

bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len);

struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features);

struct sk_buff *skb_vlan_untag(struct sk_buff *skb);

net/core/skbuff.c

+6 −5
Original line number Diff line number Diff line
@@ -4955,19 +4955,20 @@ static inline bool skb_gso_size_check(const struct sk_buff *skb, 
}



/**

 * skb_gso_validate_mtu - Return in case such skb fits a given MTU

 * skb_gso_validate_network_len - Will a split GSO skb fit into a given MTU?

 *

 * @skb: GSO skb

 * @mtu: MTU to validate against

 *

 * skb_gso_validate_mtu validates if a given skb will fit a wanted MTU

 * once split.

 * skb_gso_validate_network_len validates if a given skb will fit a

 * wanted MTU once split. It considers L3 headers, L4 headers, and the

 * payload.

 */

bool skb_gso_validate_mtu(const struct sk_buff *skb, unsigned int mtu)

bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu)

{

	return skb_gso_size_check(skb, skb_gso_network_seglen(skb), mtu);

}

EXPORT_SYMBOL_GPL(skb_gso_validate_mtu);

EXPORT_SYMBOL_GPL(skb_gso_validate_network_len);



/**

 * skb_gso_validate_mac_len - Will a split GSO skb fit in a given length?

net/ipv4/ip_forward.c

+1 −1
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu) 
	if (skb->ignore_df)

		return false;



	if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))

	if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))

		return false;



	return true;

net/ipv4/ip_output.c

+1 −1
Original line number Diff line number Diff line
@@ -248,7 +248,7 @@ static int ip_finish_output_gso(struct net *net, struct sock *sk, 


	/* common case: seglen is <= mtu

	 */

	if (skb_gso_validate_mtu(skb, mtu))

	if (skb_gso_validate_network_len(skb, mtu))

		return ip_finish_output2(net, sk, skb);



	/* Slowpath -  GSO segment length exceeds the egress MTU.

net/ipv4/netfilter/nf_flow_table_ipv4.c

+1 −1
Original line number Diff line number Diff line
@@ -186,7 +186,7 @@ static bool __nf_flow_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu) 
	if ((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0)

		return false;



	if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))

	if (skb_is_gso(skb) && skb_gso_validate_network_len(skb, mtu))

		return false;



	return true;

CRA Git | Maintained and supported by SUSTech CRA and CCSE