net: Convert protocol error handlers from void to int
We'll need this to handle ICMP errors for tunnels without a sending socket
(i.e. FoU and GUE). There, we might have to look up different types of IP
tunnels, registered as network protocols, before we get a match, so we
want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both
inet_protos and inet6_protos. These error codes will be used in the next
patch.
For consistency, return sensible error codes in protocol error handlers
whenever handlers can't handle errors because, even if valid, they don't
match a protocol or any of its states.
This has no effect on existing error handling paths.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 2c67af6..76a9a5f 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -121,8 +121,8 @@ static unsigned int ipgre_net_id __read_mostly;
static unsigned int gre_tap_net_id __read_mostly;
static unsigned int erspan_net_id __read_mostly;
-static void ipgre_err(struct sk_buff *skb, u32 info,
- const struct tnl_ptk_info *tpi)
+static int ipgre_err(struct sk_buff *skb, u32 info,
+ const struct tnl_ptk_info *tpi)
{
/* All the routers (except for Linux) return only
@@ -146,36 +146,6 @@ static void ipgre_err(struct sk_buff *skb, u32 info,
unsigned int data_len = 0;
struct ip_tunnel *t;
- switch (type) {
- default:
- case ICMP_PARAMETERPROB:
- return;
-
- case ICMP_DEST_UNREACH:
- switch (code) {
- case ICMP_SR_FAILED:
- case ICMP_PORT_UNREACH:
- /* Impossible event. */
- return;
- default:
- /* All others are translated to HOST_UNREACH.
- rfc2003 contains "deep thoughts" about NET_UNREACH,
- I believe they are just ether pollution. --ANK
- */
- break;
- }
- break;
-
- case ICMP_TIME_EXCEEDED:
- if (code != ICMP_EXC_TTL)
- return;
- data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
- break;
-
- case ICMP_REDIRECT:
- break;
- }
-
if (tpi->proto == htons(ETH_P_TEB))
itn = net_generic(net, gre_tap_net_id);
else if (tpi->proto == htons(ETH_P_ERSPAN) ||
@@ -189,27 +159,59 @@ static void ipgre_err(struct sk_buff *skb, u32 info,
iph->daddr, iph->saddr, tpi->key);
if (!t)
- return;
+ return -ENOENT;
+
+ switch (type) {
+ default:
+ case ICMP_PARAMETERPROB:
+ return 0;
+
+ case ICMP_DEST_UNREACH:
+ switch (code) {
+ case ICMP_SR_FAILED:
+ case ICMP_PORT_UNREACH:
+ /* Impossible event. */
+ return 0;
+ default:
+ /* All others are translated to HOST_UNREACH.
+ rfc2003 contains "deep thoughts" about NET_UNREACH,
+ I believe they are just ether pollution. --ANK
+ */
+ break;
+ }
+ break;
+
+ case ICMP_TIME_EXCEEDED:
+ if (code != ICMP_EXC_TTL)
+ return 0;
+ data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
+ break;
+
+ case ICMP_REDIRECT:
+ break;
+ }
#if IS_ENABLED(CONFIG_IPV6)
if (tpi->proto == htons(ETH_P_IPV6) &&
!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len,
type, data_len))
- return;
+ return 0;
#endif
if (t->parms.iph.daddr == 0 ||
ipv4_is_multicast(t->parms.iph.daddr))
- return;
+ return 0;
if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
- return;
+ return 0;
if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
t->err_count++;
else
t->err_count = 1;
t->err_time = jiffies;
+
+ return 0;
}
static void gre_err(struct sk_buff *skb, u32 info)