This is a note to let you know that I've just added the patch titled
netfilter: nft_compat: reject unused compat flag
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netfilter-nft_compat-reject-unused-compat-flag.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7518264971e40b0d334e5bf5af839c46dab473bb
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Thu Feb 1 23:33:29 2024 +0100
netfilter: nft_compat: reject unused compat flag
[ 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>
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 6a08c03a511d..bc70d580e8d6 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -243,9 +243,11 @@ 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 f01f3cf4f8f5..44583da6ec6b 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -204,7 +204,8 @@ 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;
