Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0e78a873 authored by Steffen Klassert's avatar Steffen Klassert
Browse files

esp4: Fix udpencap for local TCP packets. 



Locally generated TCP packets are usually cloned, so we
do skb_cow_data() on this packets. After that we need to
reload the pointer to the esp header. On udpencap this
header has an offset to skb_transport_header, so take this
offset into account.

Fixes: 67d349ed ("net/esp4: Fix invalid esph pointer crash")
Fixes: fca11ebd ("esp4: Reorganize esp_output")
Reported-by: default avatarDon Bowman <db@donbowman.ca>
Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
parent f411af68

net/ipv4/esp4.c

+4 −1
Original line number Diff line number Diff line
@@ -248,6 +248,7 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * 
	u8 *tail;

	u8 *vaddr;

	int nfrags;

	int esph_offset;

	struct page *page;

	struct sk_buff *trailer;

	int tailen = esp->tailen;
@@ -313,11 +314,13 @@ int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info * 
	}



cow:

	esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb);



	nfrags = skb_cow_data(skb, tailen, &trailer);

	if (nfrags < 0)

		goto out;

	tail = skb_tail_pointer(trailer);

	esp->esph = ip_esp_hdr(skb);

	esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset);



skip_cow:

	esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);