net_sched: fix use of uninitialized ethertype variable in cls_flower
The addition of VLAN support caused a possible use of uninitialized
data if we encounter a zero TCA_FLOWER_KEY_ETH_TYPE key, as pointed
out by "gcc -Wmaybe-uninitialized":
net/sched/cls_flower.c: In function 'fl_change':
net/sched/cls_flower.c:366:22: error: 'ethertype' may be used uninitialized in this function [-Werror=maybe-uninitialized]
This changes the code to only set the ethertype field if it
was nonzero, as before the patch.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 9399ae9a6cb2 ("net_sched: flower: Add vlan support")
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 532ab67..cf9ad5b 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -353,18 +353,19 @@
mask->eth.src, TCA_FLOWER_KEY_ETH_SRC_MASK,
sizeof(key->eth.src));
- if (tb[TCA_FLOWER_KEY_ETH_TYPE])
+ if (tb[TCA_FLOWER_KEY_ETH_TYPE]) {
ethertype = nla_get_be16(tb[TCA_FLOWER_KEY_ETH_TYPE]);
- if (ethertype == htons(ETH_P_8021Q)) {
- fl_set_key_vlan(tb, &key->vlan, &mask->vlan);
- fl_set_key_val(tb, &key->basic.n_proto,
- TCA_FLOWER_KEY_VLAN_ETH_TYPE,
- &mask->basic.n_proto, TCA_FLOWER_UNSPEC,
- sizeof(key->basic.n_proto));
- } else {
- key->basic.n_proto = ethertype;
- mask->basic.n_proto = cpu_to_be16(~0);
+ if (ethertype == htons(ETH_P_8021Q)) {
+ fl_set_key_vlan(tb, &key->vlan, &mask->vlan);
+ fl_set_key_val(tb, &key->basic.n_proto,
+ TCA_FLOWER_KEY_VLAN_ETH_TYPE,
+ &mask->basic.n_proto, TCA_FLOWER_UNSPEC,
+ sizeof(key->basic.n_proto));
+ } else {
+ key->basic.n_proto = ethertype;
+ mask->basic.n_proto = cpu_to_be16(~0);
+ }
}
if (key->basic.n_proto == htons(ETH_P_IP) ||