diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c
index 40c261cd0af3..f98d1d4b42c3 100644
--- a/net/netfilter/nf_conntrack_bpf.c
+++ b/net/netfilter/nf_conntrack_bpf.c
@@ -65,6 +65,15 @@ enum {
 	NF_BPF_CT_OPTS_SZ = 16,
 };
 
+static void *bpf_ct_opts_result(struct bpf_ct_opts *opts, u32 opts__sz, void *ret)
+{
+	if (!IS_ERR(ret))
+		return ret;
+	if (opts__sz >= offsetofend(struct bpf_ct_opts, error))
+		opts->error = PTR_ERR(ret);
+	return NULL;
+}
+
 static int bpf_nf_ct_tuple_parse(struct bpf_sock_tuple *bpf_tuple,
 				 u32 tuple_len, u8 protonum, u8 dir,
 				 struct nf_conntrack_tuple *tuple)
@@ -297,12 +306,7 @@ bpf_xdp_ct_alloc(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple,
 
 	nfct = __bpf_nf_ct_alloc_entry(dev_net(ctx->rxq->dev), bpf_tuple, tuple__sz,
 				       opts, opts__sz, 10);
-	if (IS_ERR(nfct)) {
-		opts->error = PTR_ERR(nfct);
-		return NULL;
-	}
-
-	return (struct nf_conn___init *)nfct;
+	return (struct nf_conn___init *)bpf_ct_opts_result(opts, opts__sz, nfct);
 }
 
 /* bpf_xdp_ct_lookup - Lookup CT entry for the given tuple, and acquire a
@@ -331,11 +335,7 @@ bpf_xdp_ct_lookup(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple,
 
 	caller_net = dev_net(ctx->rxq->dev);
 	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);
-	if (IS_ERR(nfct)) {
-		opts->error = PTR_ERR(nfct);
-		return NULL;
-	}
-	return nfct;
+	return bpf_ct_opts_result(opts, opts__sz, nfct);
 }
 
 /* bpf_skb_ct_alloc - Allocate a new CT entry
@@ -363,12 +363,7 @@ bpf_skb_ct_alloc(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple,
 
 	net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);
 	nfct = __bpf_nf_ct_alloc_entry(net, bpf_tuple, tuple__sz, opts, opts__sz, 10);
-	if (IS_ERR(nfct)) {
-		opts->error = PTR_ERR(nfct);
-		return NULL;
-	}
-
-	return (struct nf_conn___init *)nfct;
+	return (struct nf_conn___init *)bpf_ct_opts_result(opts, opts__sz, nfct);
 }
 
 /* bpf_skb_ct_lookup - Lookup CT entry for the given tuple, and acquire a
@@ -397,11 +392,7 @@ bpf_skb_ct_lookup(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple,
 
 	caller_net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);
 	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);
-	if (IS_ERR(nfct)) {
-		opts->error = PTR_ERR(nfct);
-		return NULL;
-	}
-	return nfct;
+	return bpf_ct_opts_result(opts, opts__sz, nfct);
 }
 
 /* bpf_ct_insert_entry - Add the provided entry into a CT map
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
index b33dba4b126e..14d4c1793aed 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
@@ -5,6 +5,8 @@
 #include "test_bpf_nf.skel.h"
 #include "test_bpf_nf_fail.skel.h"
 
+#define CT_OPTS_ERROR_GUARD 0x12345678
+
 static char log_buf[1024 * 1024];
 
 struct {
@@ -119,6 +121,10 @@ static void test_bpf_nf_ct(int mode)
 	ASSERT_EQ(skel->bss->test_einval_reserved_new, -EINVAL, "Test EINVAL for reserved in new struct not set to 0");
 	ASSERT_EQ(skel->bss->test_einval_netns_id, -EINVAL, "Test EINVAL for netns_id < -1");
 	ASSERT_EQ(skel->bss->test_einval_len_opts, -EINVAL, "Test EINVAL for len__opts != NF_BPF_CT_OPTS_SZ");
+	ASSERT_EQ(skel->bss->test_einval_len_opts_small_lookup, CT_OPTS_ERROR_GUARD,
+		  "Test no error write for lookup opts__sz before error field");
+	ASSERT_EQ(skel->bss->test_einval_len_opts_small_alloc, CT_OPTS_ERROR_GUARD,
+		  "Test no error write for alloc opts__sz before error field");
 	ASSERT_EQ(skel->bss->test_eproto_l4proto, -EPROTO, "Test EPROTO for l4proto != TCP or UDP");
 	ASSERT_EQ(skel->bss->test_enonet_netns_id, -ENONET, "Test ENONET for bad but valid netns_id");
 	ASSERT_EQ(skel->bss->test_enoent_lookup, -ENOENT, "Test ENOENT for failed lookup");
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_nf.c b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
index 076fbf03a126..df43649ecb78 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_nf.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_nf.c
@@ -10,6 +10,8 @@
 #define EINVAL 22
 #define ENOENT 2
 
+#define CT_OPTS_ERROR_GUARD 0x12345678
+
 #define NF_CT_ZONE_DIR_ORIG (1 << IP_CT_DIR_ORIGINAL)
 #define NF_CT_ZONE_DIR_REPL (1 << IP_CT_DIR_REPLY)
 
@@ -19,6 +21,8 @@ int test_einval_reserved = 0;
 int test_einval_reserved_new = 0;
 int test_einval_netns_id = 0;
 int test_einval_len_opts = 0;
+int test_einval_len_opts_small_lookup = 0;
+int test_einval_len_opts_small_alloc = 0;
 int test_eproto_l4proto = 0;
 int test_enonet_netns_id = 0;
 int test_enoent_lookup = 0;
@@ -124,6 +128,28 @@ nf_ct_test(struct nf_conn *(*lookup_fn)(void *, struct bpf_sock_tuple *, u32,
 	else
 		test_einval_len_opts = opts_def.error;
 
+	opts_def.error = CT_OPTS_ERROR_GUARD;
+	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
+		       sizeof(opts_def.netns_id));
+	if (ct) {
+		bpf_ct_release(ct);
+		test_einval_len_opts_small_lookup = -EINVAL;
+	} else {
+		test_einval_len_opts_small_lookup = opts_def.error;
+	}
+
+	opts_def.error = CT_OPTS_ERROR_GUARD;
+	ct = alloc_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
+		      sizeof(opts_def.netns_id));
+	if (ct) {
+		ct = bpf_ct_insert_entry(ct);
+		if (ct)
+			bpf_ct_release(ct);
+		test_einval_len_opts_small_alloc = -EINVAL;
+	} else {
+		test_einval_len_opts_small_alloc = opts_def.error;
+	}
+
 	opts_def.l4proto = IPPROTO_ICMP;
 	ct = lookup_fn(ctx, &bpf_tuple, sizeof(bpf_tuple.ipv4), &opts_def,
 		       sizeof(opts_def));