ieee802154: 6lowpan: ensure MTU of 1280 for 6lowpan
This patch drops the userspace accessable sysfs entry for the maximum
datagram size of a 6LoWPAN fragment packet.
A fragment should not have a datagram size value greater than 1280 byte.
Instead of make this value configurable, we accept 1280 datagram size
fragment packets only.
Signed-off-by: Martin Townsend <martin.townsend@xsilon.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/netns/ieee802154_6lowpan.h b/include/net/netns/ieee802154_6lowpan.h
index e207096..8170f8d 100644
--- a/include/net/netns/ieee802154_6lowpan.h
+++ b/include/net/netns/ieee802154_6lowpan.h
@@ -16,7 +16,6 @@
struct netns_ieee802154_lowpan {
struct netns_sysctl_lowpan sysctl;
struct netns_frags frags;
- int max_dsize;
};
#endif
diff --git a/net/ieee802154/reassembly.c b/net/ieee802154/reassembly.c
index ffec6ce..32755cb7 100644
--- a/net/ieee802154/reassembly.c
+++ b/net/ieee802154/reassembly.c
@@ -355,8 +355,6 @@
struct net *net = dev_net(skb->dev);
struct lowpan_frag_info *frag_info = lowpan_cb(skb);
struct ieee802154_addr source, dest;
- struct netns_ieee802154_lowpan *ieee802154_lowpan =
- net_ieee802154_lowpan(net);
int err;
source = mac_cb(skb)->source;
@@ -366,8 +364,10 @@
if (err < 0)
goto err;
- if (frag_info->d_size > ieee802154_lowpan->max_dsize)
+ if (frag_info->d_size > IPV6_MIN_MTU) {
+ net_warn_ratelimited("lowpan_frag_rcv: datagram size exceeds MTU\n");
goto err;
+ }
fq = fq_find(net, frag_info, &source, &dest);
if (fq != NULL) {
@@ -415,13 +415,6 @@
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
- {
- .procname = "6lowpanfrag_max_datagram_size",
- .data = &init_net.ieee802154_lowpan.max_dsize,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec
- },
{ }
};
@@ -458,7 +451,6 @@
table[1].data = &ieee802154_lowpan->frags.low_thresh;
table[1].extra2 = &ieee802154_lowpan->frags.high_thresh;
table[2].data = &ieee802154_lowpan->frags.timeout;
- table[3].data = &ieee802154_lowpan->max_dsize;
/* Don't export sysctls to unprivileged users */
if (net->user_ns != &init_user_ns)
@@ -533,7 +525,6 @@
ieee802154_lowpan->frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
ieee802154_lowpan->frags.low_thresh = IPV6_FRAG_LOW_THRESH;
ieee802154_lowpan->frags.timeout = IPV6_FRAG_TIMEOUT;
- ieee802154_lowpan->max_dsize = 0xFFFF;
inet_frags_init_net(&ieee802154_lowpan->frags);
