Commit b7fe10e5 authored by Tom Herbert's avatar Tom Herbert Committed by David S. Miller
Browse files

gro: Fix remcsum offload to deal with frags in GRO 



The remote checksum offload GRO did not consider the case that frag0
might be in use. This patch fixes that by accessing headers using the
skb_gro functions and not saving offsets relative to skb->head.

Signed-off-by: default avatarTom Herbert <tom@herbertland.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9a873c71

drivers/net/vxlan.c

+9 −14
Original line number Diff line number Diff line
@@ -519,10 +519,10 @@ static struct vxlanhdr *vxlan_gro_remcsum(struct sk_buff *skb, 
					  u32 data, struct gro_remcsum *grc,

					  bool nopartial)

{

	size_t start, offset, plen;

	size_t start, offset;



	if (skb->remcsum_offload)

		return NULL;

		return vh;



	if (!NAPI_GRO_CB(skb)->csum_valid)

		return NULL;
@@ -532,16 +532,7 @@ static struct vxlanhdr *vxlan_gro_remcsum(struct sk_buff *skb, 
			  offsetof(struct udphdr, check) :

			  offsetof(struct tcphdr, check));



	plen = hdrlen + offset + sizeof(u16);



	/* Pull checksum that will be written */

	if (skb_gro_header_hard(skb, off + plen)) {

		vh = skb_gro_header_slow(skb, off + plen, off);

		if (!vh)

			return NULL;

	}



	skb_gro_remcsum_process(skb, (void *)vh + hdrlen,

	vh = skb_gro_remcsum_process(skb, (void *)vh, off, hdrlen,

				     start, offset, grc, nopartial);



	skb->remcsum_offload = 1;
@@ -573,7 +564,6 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head, 
			goto out;

	}



	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */

	skb_gro_postpull_rcsum(skb, vh, sizeof(struct vxlanhdr));



	flags = ntohl(vh->vx_flags);
@@ -588,6 +578,8 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head, 
			goto out;

	}



	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */



	flush = 0;



	for (p = *head; p; p = p->next) {
@@ -1110,6 +1102,9 @@ static struct vxlanhdr *vxlan_remcsum(struct sk_buff *skb, struct vxlanhdr *vh, 
{

	size_t start, offset, plen;



	if (skb->remcsum_offload)

		return vh;



	start = (data & VXLAN_RCO_MASK) << VXLAN_RCO_SHIFT;

	offset = start + ((data & VXLAN_RCO_UDP) ?

			  offsetof(struct udphdr, check) :

include/linux/netdevice.h

+32 −12
Original line number Diff line number Diff line
@@ -2311,8 +2311,7 @@ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb); 


static inline bool skb_at_gro_remcsum_start(struct sk_buff *skb)

{

	return (NAPI_GRO_CB(skb)->gro_remcsum_start - skb_headroom(skb) ==

		skb_gro_offset(skb));

	return (NAPI_GRO_CB(skb)->gro_remcsum_start == skb_gro_offset(skb));

}



static inline bool __skb_gro_checksum_validate_needed(struct sk_buff *skb,
@@ -2408,37 +2407,58 @@ static inline void skb_gro_remcsum_init(struct gro_remcsum *grc) 
	grc->delta = 0;

}



static inline void skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,

static inline void *skb_gro_remcsum_process(struct sk_buff *skb, void *ptr,

					    unsigned int off, size_t hdrlen,

					    int start, int offset,

					    struct gro_remcsum *grc,

					    bool nopartial)

{

	__wsum delta;

	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);



	BUG_ON(!NAPI_GRO_CB(skb)->csum_valid);



	if (!nopartial) {

		NAPI_GRO_CB(skb)->gro_remcsum_start =

		    ((unsigned char *)ptr + start) - skb->head;

		return;

		NAPI_GRO_CB(skb)->gro_remcsum_start = off + hdrlen + start;

		return ptr;

	}



	delta = remcsum_adjust(ptr, NAPI_GRO_CB(skb)->csum, start, offset);

	ptr = skb_gro_header_fast(skb, off);

	if (skb_gro_header_hard(skb, off + plen)) {

		ptr = skb_gro_header_slow(skb, off + plen, off);

		if (!ptr)

			return NULL;

	}



	delta = remcsum_adjust(ptr + hdrlen, NAPI_GRO_CB(skb)->csum,

			       start, offset);



	/* Adjust skb->csum since we changed the packet */

	NAPI_GRO_CB(skb)->csum = csum_add(NAPI_GRO_CB(skb)->csum, delta);



	grc->offset = (ptr + offset) - (void *)skb->head;

	grc->offset = off + hdrlen + offset;

	grc->delta = delta;



	return ptr;

}



static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,

					   struct gro_remcsum *grc)

{

	void *ptr;

	size_t plen = grc->offset + sizeof(u16);



	if (!grc->delta)

		return;



	remcsum_unadjust((__sum16 *)(skb->head + grc->offset), grc->delta);

	ptr = skb_gro_header_fast(skb, grc->offset);

	if (skb_gro_header_hard(skb, grc->offset + sizeof(u16))) {

		ptr = skb_gro_header_slow(skb, plen, grc->offset);

		if (!ptr)

			return;

	}



	remcsum_unadjust((__sum16 *)ptr, grc->delta);

}



static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,

net/ipv4/fou.c

+12 −16
Original line number Diff line number Diff line
@@ -79,7 +79,11 @@ static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr, 
	__be16 *pd = data;

	size_t start = ntohs(pd[0]);

	size_t offset = ntohs(pd[1]);

	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);

	size_t plen = sizeof(struct udphdr) + hdrlen +

	    max_t(size_t, offset + sizeof(u16), start);



	if (skb->remcsum_offload)

		return guehdr;



	if (!pskb_may_pull(skb, plen))

		return NULL;
@@ -221,28 +225,20 @@ out_unlock: 


static struct guehdr *gue_gro_remcsum(struct sk_buff *skb, unsigned int off,

				      struct guehdr *guehdr, void *data,

				      size_t hdrlen, u8 ipproto,

				      struct gro_remcsum *grc, bool nopartial)

				      size_t hdrlen, struct gro_remcsum *grc,

				      bool nopartial)

{

	__be16 *pd = data;

	size_t start = ntohs(pd[0]);

	size_t offset = ntohs(pd[1]);

	size_t plen = hdrlen + max_t(size_t, offset + sizeof(u16), start);



	if (skb->remcsum_offload)

		return NULL;

		return guehdr;



	if (!NAPI_GRO_CB(skb)->csum_valid)

		return NULL;



	/* Pull checksum that will be written */

	if (skb_gro_header_hard(skb, off + plen)) {

		guehdr = skb_gro_header_slow(skb, off + plen, off);

		if (!guehdr)

			return NULL;

	}



	skb_gro_remcsum_process(skb, (void *)guehdr + hdrlen,

	guehdr = skb_gro_remcsum_process(skb, (void *)guehdr, off, hdrlen,

					 start, offset, grc, nopartial);



	skb->remcsum_offload = 1;
@@ -307,10 +303,10 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head, 


		if (flags & GUE_PFLAG_REMCSUM) {

			guehdr = gue_gro_remcsum(skb, off, guehdr,

						 data + doffset, hdrlen,

						 guehdr->proto_ctype, &grc,

						 data + doffset, hdrlen, &grc,

						 !!(fou->flags &

						    FOU_F_REMCSUM_NOPARTIAL));



			if (!guehdr)

				goto out;

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