[NETFILTER]: Fix missing src port initialization in tftp expectation mask

Reported by David Ahern <[e-mail]>, netfilter bugzilla #426.

Signed-off-by: Patrick McHardy <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/ipv4/netfilter/ip_conntrack_tftp.c

···
 
 		exp->tuple = ct->tuplehash[IP_CT_DIR_REPLY].tuple;
 		exp->mask.src.ip = 0xffffffff;
+		exp->mask.src.u.udp.port = 0;
 		exp->mask.dst.ip = 0xffffffff;
 		exp->mask.dst.u.udp.port = 0xffff;
 		exp->mask.dst.protonum = 0xff;