ipv6: Disallow rediculious flowlabel option sizes.
Just like PKTINFO, limit the options area to 64K.
Based upon report by Eric Sesterhenn and analysis by
Roland Dreier.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index c62dd24..7712578 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -323,17 +323,21 @@
fl_create(struct net *net, struct in6_flowlabel_req *freq, char __user *optval,
int optlen, int *err_p)
{
- struct ip6_flowlabel *fl;
+ struct ip6_flowlabel *fl = NULL;
int olen;
int addr_type;
int err;
+ olen = optlen - CMSG_ALIGN(sizeof(*freq));
+ err = -EINVAL;
+ if (olen > 64 * 1024)
+ goto done;
+
err = -ENOMEM;
fl = kzalloc(sizeof(*fl), GFP_KERNEL);
if (fl == NULL)
goto done;
- olen = optlen - CMSG_ALIGN(sizeof(*freq));
if (olen > 0) {
struct msghdr msg;
struct flowi flowi;