[PATCH net-next v4 05/13] net/sched: cls_flower: add policy for TCA_FLOWER_KEY_FLAGS

From: Asbjørn Sloth Tønnesen
Date: Fri Jul 12 2024 - 22:21:58 EST


This policy guards fl_set_key_flags() from seeing flags
not used in the context of TCA_FLOWER_KEY_FLAGS.

In order For the policy check to be performed with the
correct endianness, then we also needs to change the
attribute type to NLA_BE32 (Thanks Davide).

TCA_FLOWER_KEY_FLAGS{,_MASK} already has a be32 comment
in include/uapi/linux/pkt_cls.h.

Signed-off-by: Asbjørn Sloth Tønnesen <ast@xxxxxxxxxxx>
Tested-by: Davide Caratti <dcaratti@xxxxxxxxxx>
Reviewed-by: Davide Caratti <dcaratti@xxxxxxxxxx>
---
net/sched/cls_flower.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 6a5cecfd95619..fc9a9a0b4897c 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -41,6 +41,10 @@
#define TCA_FLOWER_KEY_CT_FLAGS_MASK \
(TCA_FLOWER_KEY_CT_FLAGS_MAX - 1)

+#define TCA_FLOWER_KEY_FLAGS_POLICY_MASK \
+ (TCA_FLOWER_KEY_FLAGS_IS_FRAGMENT | \
+ TCA_FLOWER_KEY_FLAGS_FRAG_IS_FIRST)
+
#define TUNNEL_FLAGS_PRESENT (\
_BITUL(IP_TUNNEL_CSUM_BIT) | \
_BITUL(IP_TUNNEL_DONT_FRAGMENT_BIT) | \
@@ -676,8 +680,10 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
[TCA_FLOWER_KEY_ENC_UDP_SRC_PORT_MASK] = { .type = NLA_U16 },
[TCA_FLOWER_KEY_ENC_UDP_DST_PORT] = { .type = NLA_U16 },
[TCA_FLOWER_KEY_ENC_UDP_DST_PORT_MASK] = { .type = NLA_U16 },
- [TCA_FLOWER_KEY_FLAGS] = { .type = NLA_U32 },
- [TCA_FLOWER_KEY_FLAGS_MASK] = { .type = NLA_U32 },
+ [TCA_FLOWER_KEY_FLAGS] = NLA_POLICY_MASK(NLA_BE32,
+ TCA_FLOWER_KEY_FLAGS_POLICY_MASK),
+ [TCA_FLOWER_KEY_FLAGS_MASK] = NLA_POLICY_MASK(NLA_BE32,
+ TCA_FLOWER_KEY_FLAGS_POLICY_MASK),
[TCA_FLOWER_KEY_ICMPV4_TYPE] = { .type = NLA_U8 },
[TCA_FLOWER_KEY_ICMPV4_TYPE_MASK] = { .type = NLA_U8 },
[TCA_FLOWER_KEY_ICMPV4_CODE] = { .type = NLA_U8 },
--
2.45.2