| Message ID | 20170609093545.GS22049@secunet.com |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Steffen Klassert <steffen.klassert@secunet.com> Date: Fri, 9 Jun 2017 11:35:46 +0200 > 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. > > This is a backport of: > commit 0e78a87306a ("esp4: Fix udpencap for local TCP packets.") > > Fixes: 67d349ed603 ("net/esp4: Fix invalid esph pointer crash") > Fixes: fca11ebde3f0 ("esp4: Reorganize esp_output") > Reported-by: Don Bowman <db@donbowman.ca> > Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Queued up for -stable, thanks Steffen.
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index b1e2444..9708a32 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -212,6 +212,7 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) u8 *iv; u8 *tail; u8 *vaddr; + int esph_offset; int blksize; int clen; int alen; @@ -392,12 +393,14 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) } cow: + esph_offset = (unsigned char *)esph - skb_transport_header(skb); + err = skb_cow_data(skb, tailen, &trailer); if (err < 0) goto error; nfrags = err; tail = skb_tail_pointer(trailer); - esph = ip_esp_hdr(skb); + esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset); skip_cow: esp_output_fill_trailer(tail, tfclen, plen, proto);
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. This is a backport of: commit 0e78a87306a ("esp4: Fix udpencap for local TCP packets.") Fixes: 67d349ed603 ("net/esp4: Fix invalid esph pointer crash") Fixes: fca11ebde3f0 ("esp4: Reorganize esp_output") Reported-by: Don Bowman <db@donbowman.ca> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> --- net/ipv4/esp4.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)