diff mbox series

[net,03/14] netfilter: nft_tproxy: restrict to prerouting hook

Message ID 20220824220330.64283-4-pablo@netfilter.org (mailing list archive)
State Accepted
Commit 18bbc3213383a82b05383827f4b1b882e3f0a5a5
Delegated to: Netdev Maintainers
Headers show
Series [net,01/14] netfilter: ebtables: reject blobs that don't provide all entry points | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net
netdev/fixes_present success Fixes tag present in non-next series
netdev/subject_prefix success Link
netdev/cover_letter success Pull request is its own cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 85 this patch: 85
netdev/cc_maintainers fail 1 blamed authors not CCed: ecklm94@gmail.com; 4 maintainers not CCed: fw@strlen.de ecklm94@gmail.com coreteam@netfilter.org kadlec@netfilter.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
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: 85 this patch: 85
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 20 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Pablo Neira Ayuso Aug. 24, 2022, 10:03 p.m. UTC
From: Florian Westphal <fw@strlen.de>

TPROXY is only allowed from prerouting, but nft_tproxy doesn't check this.
This fixes a crash (null dereference) when using tproxy from e.g. output.

Fixes: 4ed8eb6570a4 ("netfilter: nf_tables: Add native tproxy support")
Reported-by: Shell Chen <xierch@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/netfilter/nft_tproxy.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/net/netfilter/nft_tproxy.c b/net/netfilter/nft_tproxy.c
index 68b2eed742df..62da25ad264b 100644
--- a/net/netfilter/nft_tproxy.c
+++ b/net/netfilter/nft_tproxy.c
@@ -312,6 +312,13 @@  static int nft_tproxy_dump(struct sk_buff *skb,
 	return 0;
 }
 
+static int nft_tproxy_validate(const struct nft_ctx *ctx,
+			       const struct nft_expr *expr,
+			       const struct nft_data **data)
+{
+	return nft_chain_validate_hooks(ctx->chain, 1 << NF_INET_PRE_ROUTING);
+}
+
 static struct nft_expr_type nft_tproxy_type;
 static const struct nft_expr_ops nft_tproxy_ops = {
 	.type		= &nft_tproxy_type,
@@ -321,6 +328,7 @@  static const struct nft_expr_ops nft_tproxy_ops = {
 	.destroy	= nft_tproxy_destroy,
 	.dump		= nft_tproxy_dump,
 	.reduce		= NFT_REDUCE_READONLY,
+	.validate	= nft_tproxy_validate,
 };
 
 static struct nft_expr_type nft_tproxy_type __read_mostly = {