diff mbox series

[net,04/13] netfilter: nft_limit: do not ignore unsupported flags

Message ID 20240118161726.14838-5-pablo@netfilter.org (mailing list archive)
State Accepted
Commit 91a139cee1202a4599a380810d93c69b5bac6197
Delegated to: Netdev Maintainers
Headers show
Series [net,01/13] netfilter: nf_tables: reject invalid set policy | expand

Checks

Context Check Description
netdev/series_format success Pull request is its own cover letter
netdev/tree_selection success Clearly marked for net
netdev/ynl success SINGLE THREAD; Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1080 this patch: 1080
netdev/cc_maintainers success CCed 0 of 0 maintainers
netdev/build_clang success Errors and warnings before: 1095 this patch: 1095
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 1095 this patch: 1095
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 37 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-01-18--21-00 (tests: 403)

Commit Message

Pablo Neira Ayuso Jan. 18, 2024, 4:17 p.m. UTC 
Bail out if userspace provides unsupported flags, otherwise future
extensions to the limit expression will be silently ignored by the
kernel.

Fixes: c7862a5f0de5 ("netfilter: nft_limit: allow to invert matching criteria")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_limit.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/net/netfilter/nft_limit.c b/net/netfilter/nft_limit.c
index 145dc62c6247..79039afde34e 100644
--- a/net/netfilter/nft_limit.c
+++ b/net/netfilter/nft_limit.c
@@ -58,6 +58,7 @@  static inline bool nft_limit_eval(struct nft_limit_priv *priv, u64 cost)
 static int nft_limit_init(struct nft_limit_priv *priv,
 			  const struct nlattr * const tb[], bool pkts)
 {
+	bool invert = false;
 	u64 unit, tokens;
 
 	if (tb[NFTA_LIMIT_RATE] == NULL ||
@@ -90,19 +91,23 @@  static int nft_limit_init(struct nft_limit_priv *priv,
 				 priv->rate);
 	}
 
+	if (tb[NFTA_LIMIT_FLAGS]) {
+		u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
+
+		if (flags & ~NFT_LIMIT_F_INV)
+			return -EOPNOTSUPP;
+
+		if (flags & NFT_LIMIT_F_INV)
+			invert = true;
+	}
+
 	priv->limit = kmalloc(sizeof(*priv->limit), GFP_KERNEL_ACCOUNT);
 	if (!priv->limit)
 		return -ENOMEM;
 
 	priv->limit->tokens = tokens;
 	priv->tokens_max = priv->limit->tokens;
-
-	if (tb[NFTA_LIMIT_FLAGS]) {
-		u32 flags = ntohl(nla_get_be32(tb[NFTA_LIMIT_FLAGS]));
-
-		if (flags & NFT_LIMIT_F_INV)
-			priv->invert = true;
-	}
+	priv->invert = invert;
 	priv->limit->last = ktime_get_ns();
 	spin_lock_init(&priv->limit->lock);