4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
[ Upstream commit 292781c3c5485ce33bd22b2ef1b2bed709b4d672 ]
Flag (1 << 0) is ignored is set, never used, reject it it with EINVAL
instead.
Fixes: 0ca743a55991 ("netfilter: nf_tables: add compatibility layer for x_tables")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/uapi/linux/netfilter/nf_tables.h | 2 ++
net/netfilter/nft_compat.c | 3 ++-
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index cc00be102b9f..39774870c864 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -238,9 +238,11 @@ enum nft_rule_attributes {
/**
* enum nft_rule_compat_flags - nf_tables rule compat flags
*
+ * @NFT_RULE_COMPAT_F_UNUSED: unused
* @NFT_RULE_COMPAT_F_INV: invert the check result
*/
enum nft_rule_compat_flags {
+ NFT_RULE_COMPAT_F_UNUSED = (1 << 0),
NFT_RULE_COMPAT_F_INV = (1 << 1),
NFT_RULE_COMPAT_F_MASK = NFT_RULE_COMPAT_F_INV,
};
diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index 2846d64659f2..95af1dbc28c1 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -207,7 +207,8 @@ static int nft_parse_compat(const struct nlattr *attr, u16 *proto, bool *inv)
return -EINVAL;
flags = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_FLAGS]));
- if (flags & ~NFT_RULE_COMPAT_F_MASK)
+ if (flags & NFT_RULE_COMPAT_F_UNUSED ||
+ flags & ~NFT_RULE_COMPAT_F_MASK)
return -EINVAL;
if (flags & NFT_RULE_COMPAT_F_INV)
*inv = true;
--
2.43.0
