iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[XFRM]: beet: fix worst case header_len calculation

Browse Source 
esp_init_state doesn't account for the beet pseudo header in the header_len
calculation, which may result in undersized skbs hitting xfrm4_beet_output,
causing unnecessary reallocations in ip_finish_output2.

The skbs should still always have enough room to avoid causing
skb_under_panic in skb_push since we have at least 16 bytes available
from LL_RESERVED_SPACE in xfrm_state_check_space.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2007-04-09 11:47:58 -07:00 committed by David S. Miller
parent c5c2523893
commit ac758e3c55
2 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/ipv4/esp4.c
View File

@ -294,7 +294,6 @@ static u32 esp4_get_mtu(struct xfrm_state *x, int mtu)
break;
case XFRM_MODE_BEET:
/* The worst case. */
mtu -= IPV4_BEET_PHMAXLEN;
mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem);
break;
}
@ -409,6 +408,8 @@ static int esp_init_state(struct xfrm_state *x)
x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen;
if (x->props.mode == XFRM_MODE_TUNNEL)
x->props.header_len += sizeof(struct iphdr);
else if (x->props.mode == XFRM_MODE_BEET)
x->props.header_len += IPV4_BEET_PHMAXLEN;
if (x->encap) {
struct xfrm_encap_tmpl *encap = x->encap;

2
net/ipv4/xfrm4_mode_beet.c
View File

@ -40,7 +40,7 @@ static int xfrm4_beet_output(struct xfrm_state *x, struct sk_buff *skb)
if (unlikely(optlen))
hdrlen += IPV4_BEET_PHMAXLEN - (optlen & 4);
skb_push(skb, x->props.header_len + hdrlen);
skb_push(skb, x->props.header_len - IPV4_BEET_PHMAXLEN + hdrlen);
skb_reset_network_header(skb);
top_iph = ip_hdr(skb);
skb->transport_header += sizeof(*iph) - hdrlen;