Merge branch 'ipvlan-Fix-insufficient-skb-linear-check'

Gao Feng says:

====================
ipvlan: Fix insufficient skb linear check

The current ipvlan codes use pskb_may_pull to get the skb linear header in
func ipvlan_get_L3_hdr, but the size isn't enough for arp and ipv6 icmp.
So it may access the unexpected momory in ipvlan_addr_lookup.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David S. Miller 2017-11-24 03:37:03 +09:00
commit 9ed33805cd
1 changed files with 27 additions and 9 deletions

View File

@ -116,7 +116,7 @@ bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6)
return false; return false;
} }
static void *ipvlan_get_L3_hdr(struct sk_buff *skb, int *type) static void *ipvlan_get_L3_hdr(struct ipvl_port *port, struct sk_buff *skb, int *type)
{ {
void *lyr3h = NULL; void *lyr3h = NULL;
@ -124,7 +124,7 @@ static void *ipvlan_get_L3_hdr(struct sk_buff *skb, int *type)
case htons(ETH_P_ARP): { case htons(ETH_P_ARP): {
struct arphdr *arph; struct arphdr *arph;
if (unlikely(!pskb_may_pull(skb, sizeof(*arph)))) if (unlikely(!pskb_may_pull(skb, arp_hdr_len(port->dev))))
return NULL; return NULL;
arph = arp_hdr(skb); arph = arp_hdr(skb);
@ -165,8 +165,26 @@ static void *ipvlan_get_L3_hdr(struct sk_buff *skb, int *type)
/* Only Neighbour Solicitation pkts need different treatment */ /* Only Neighbour Solicitation pkts need different treatment */
if (ipv6_addr_any(&ip6h->saddr) && if (ipv6_addr_any(&ip6h->saddr) &&
ip6h->nexthdr == NEXTHDR_ICMP) { ip6h->nexthdr == NEXTHDR_ICMP) {
struct icmp6hdr *icmph;
if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph))))
return NULL;
ip6h = ipv6_hdr(skb);
icmph = (struct icmp6hdr *)(ip6h + 1);
if (icmph->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) {
/* Need to access the ipv6 address in body */
if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph)
+ sizeof(struct in6_addr))))
return NULL;
ip6h = ipv6_hdr(skb);
icmph = (struct icmp6hdr *)(ip6h + 1);
}
*type = IPVL_ICMPV6; *type = IPVL_ICMPV6;
lyr3h = ip6h + 1; lyr3h = icmph;
} }
break; break;
} }
@ -510,7 +528,7 @@ static int ipvlan_xmit_mode_l3(struct sk_buff *skb, struct net_device *dev)
struct ipvl_addr *addr; struct ipvl_addr *addr;
int addr_type; int addr_type;
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type);
if (!lyr3h) if (!lyr3h)
goto out; goto out;
@ -539,7 +557,7 @@ static int ipvlan_xmit_mode_l2(struct sk_buff *skb, struct net_device *dev)
if (!ipvlan_is_vepa(ipvlan->port) && if (!ipvlan_is_vepa(ipvlan->port) &&
ether_addr_equal(eth->h_dest, eth->h_source)) { ether_addr_equal(eth->h_dest, eth->h_source)) {
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type);
if (lyr3h) { if (lyr3h) {
addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true); addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
if (addr) { if (addr) {
@ -606,7 +624,7 @@ static bool ipvlan_external_frame(struct sk_buff *skb, struct ipvl_port *port)
int addr_type; int addr_type;
if (ether_addr_equal(eth->h_source, skb->dev->dev_addr)) { if (ether_addr_equal(eth->h_source, skb->dev->dev_addr)) {
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
if (!lyr3h) if (!lyr3h)
return true; return true;
@ -627,7 +645,7 @@ static rx_handler_result_t ipvlan_handle_mode_l3(struct sk_buff **pskb,
struct sk_buff *skb = *pskb; struct sk_buff *skb = *pskb;
rx_handler_result_t ret = RX_HANDLER_PASS; rx_handler_result_t ret = RX_HANDLER_PASS;
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
if (!lyr3h) if (!lyr3h)
goto out; goto out;
@ -666,7 +684,7 @@ static rx_handler_result_t ipvlan_handle_mode_l2(struct sk_buff **pskb,
} else { } else {
struct ipvl_addr *addr; struct ipvl_addr *addr;
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
if (!lyr3h) if (!lyr3h)
return ret; return ret;
@ -717,7 +735,7 @@ static struct ipvl_addr *ipvlan_skb_to_addr(struct sk_buff *skb,
if (!port || port->mode != IPVLAN_MODE_L3S) if (!port || port->mode != IPVLAN_MODE_L3S)
goto out; goto out;
lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type);
if (!lyr3h) if (!lyr3h)
goto out; goto out;