[PATCH 5.16 1021/1039] net: mscc: ocelot: fix using match before it is set

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 21:00:28 EST


From: Tom Rix <trix@xxxxxxxxxx>

commit baa59504c1cd0cca7d41954a45ee0b3dc78e41a0 upstream.

Clang static analysis reports this issue
ocelot_flower.c:563:8: warning: 1st function call argument
is an uninitialized value
!is_zero_ether_addr(match.mask->dst)) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The variable match is used before it is set. So move the
block.

Fixes: 75944fda1dfe ("net: mscc: ocelot: offload ingress skbedit and vlan actions to VCAP IS1")
Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mscc/ocelot_flower.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/mscc/ocelot_flower.c
+++ b/drivers/net/ethernet/mscc/ocelot_flower.c
@@ -521,13 +521,6 @@ ocelot_flower_parse_key(struct ocelot *o
return -EOPNOTSUPP;
}

- if (filter->block_id == VCAP_IS1 &&
- !is_zero_ether_addr(match.mask->dst)) {
- NL_SET_ERR_MSG_MOD(extack,
- "Key type S1_NORMAL cannot match on destination MAC");
- return -EOPNOTSUPP;
- }
-
/* The hw support mac matches only for MAC_ETYPE key,
* therefore if other matches(port, tcp flags, etc) are added
* then just bail out
@@ -542,6 +535,14 @@ ocelot_flower_parse_key(struct ocelot *o
return -EOPNOTSUPP;

flow_rule_match_eth_addrs(rule, &match);
+
+ if (filter->block_id == VCAP_IS1 &&
+ !is_zero_ether_addr(match.mask->dst)) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Key type S1_NORMAL cannot match on destination MAC");
+ return -EOPNOTSUPP;
+ }
+
filter->key_type = OCELOT_VCAP_KEY_ETYPE;
ether_addr_copy(filter->key.etype.dmac.value,
match.key->dst);