diff -Naur linux-2.6.17.8.orig/net/ipv4/igmp.c linux-2.6.17.8/net/ipv4/igmp.c
--- linux-2.6.17.8.orig/net/ipv4/igmp.c	2006-08-07 06:18:54.000000000 +0200
+++ linux-2.6.17.8/net/ipv4/igmp.c	2006-08-10 10:38:04.000000000 +0200
@@ -2206,9 +2206,10 @@
 			(void) ip_mc_leave_src(sk, iml, in_dev);
 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
 			in_dev_put(in_dev);
-		}
-		sock_kfree_s(sk, iml, sizeof(*iml));
+		} else if (iml->sflist != NULL)
+			sock_kfree_s(sk, iml->sflist, IP_SFLSIZE(iml->sflist->sl_max));
 
+		sock_kfree_s(sk, iml, sizeof(*iml));
 	}
 	rtnl_unlock();
 }