[PATCH nf] netfilter: nft_osf: restrict it to ipv6

[PATCH nf] netfilter: nft_osf: restrict it to ipv6

[Pablo Neira Ayuso]

This expression only supports for ipv4, restrict it.

Fixes: b96af92d6eaf ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_osf.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index 1c0b493ef0a9..bdc2f6c90e2f 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -28,6 +28,11 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
 	struct nf_osf_data data;
 	struct tcphdr _tcph;
 
+	if (nft_pf(pkt) != NFPROTO_IPV4) {
+		regs->verdict.code = NFT_BREAK;
+		return;
+	}
+
 	if (pkt->tprot != IPPROTO_TCP) {
 		regs->verdict.code = NFT_BREAK;
 		return;
@@ -114,7 +119,6 @@ static int nft_osf_validate(const struct nft_ctx *ctx,
 
 	switch (ctx->family) {
 	case NFPROTO_IPV4:
-	case NFPROTO_IPV6:
 	case NFPROTO_INET:
 		hooks = (1 << NF_INET_LOCAL_IN) |
 			(1 << NF_INET_PRE_ROUTING) |
-- 
2.47.3

Re: [PATCH nf] netfilter: nft_osf: restrict it to ipv6

[Florian Westphal]

Pablo Neira Ayuso <pablo@netfilter.org> wrote:
> This expression only supports for ipv4, restrict it.

:-O

Acked-by: Florian Westphal <fw@strlen.de>

Re: [PATCH nf] netfilter: nft_osf: restrict it to ipv6

[Fernando Fernandez Mancera]

On 4/14/26 1:08 PM, Pablo Neira Ayuso wrote:
> This expression only supports for ipv4, restrict it.
> 
> Fixes: b96af92d6eaf ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
> ---
>   net/netfilter/nft_osf.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
> index 1c0b493ef0a9..bdc2f6c90e2f 100644
> --- a/net/netfilter/nft_osf.c
> +++ b/net/netfilter/nft_osf.c
> @@ -28,6 +28,11 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
>   	struct nf_osf_data data;
>   	struct tcphdr _tcph;
>   
> +	if (nft_pf(pkt) != NFPROTO_IPV4) {
> +		regs->verdict.code = NFT_BREAK;
> +		return;
> +	}
> +
>   	if (pkt->tprot != IPPROTO_TCP) {
>   		regs->verdict.code = NFT_BREAK;
>   		return;
> @@ -114,7 +119,6 @@ static int nft_osf_validate(const struct nft_ctx *ctx,
>   
>   	switch (ctx->family) {
>   	case NFPROTO_IPV4:
> -	case NFPROTO_IPV6:
>   	case NFPROTO_INET:
>   		hooks = (1 << NF_INET_LOCAL_IN) |
>   			(1 << NF_INET_PRE_ROUTING) |

Reviewed-by: Fernando Fernandez Mancera <fmancera@suse.de>

I have the feeling I should re-review everything I did 7 years ago :-)

Thanks!