From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F17D33A4505 for ; Sat, 7 Mar 2026 19:54:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772913271; cv=none; b=Qhlxly65oAnPvelbpEErHyc6hLEod4sYUKJcOGhpQRaJCWIJdR8C4/H6K2VQqA2xjLWzH7WYmy4G48/NMu5CTR9BqEAo0tiPPNgxRUuMFjK0RUySHWEQMRHudbDSRKmePg2KjizKgLodIjEFmb1Gr+bHmDxivACixgRrmvtowdU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772913271; c=relaxed/simple; bh=1y3sIRO+i9mMyJAEIpsi5HHAo6pg1KHpSiMVhy4nVYk=; h=Mime-Version:Content-Type:Date:Message-Id:Subject:Cc:To:From: References:In-Reply-To; b=SxvzI7tFx3KrUqcG9rQT3qphIL4Vn1SMCVI0sD5/Pm0vktiI0ieiUrTiBVDrrf6UjqafujlzrOOl0oOz7WEYs9wsgV59L5G6TC/t3yXamWdMWYRMG5la8NFmrlRJm5WxDAyQ2tYqjR+qKTaBAZxwEGkqsBBZFZzUfU+4XeTn+1k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=g/W15PpL; arc=none smtp.client-ip=209.85.128.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="g/W15PpL" Received: by mail-wm1-f47.google.com with SMTP id 5b1f17b1804b1-4836e3288cdso70517715e9.0 for ; Sat, 07 Mar 2026 11:54:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1772913267; x=1773518067; darn=vger.kernel.org; h=in-reply-to:references:from:to:cc:subject:message-id:date :content-transfer-encoding:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=wRapRrMQzfVb1zc8bjuWvKtij1EZN6NyZd+CGQgeUqY=; b=g/W15PpLYwevvKhlFNQMj8vDmrLs6bnDdNjvdRwldmaau4ruLQ9TG6xRkiyCHqzwu6 7xFUqz4O8LyQanSHBuiWo5moUnQsBGP7NumZQvshTWRcersdQLEgMQem5MXec3g2KLZI nWTobCt3XFoaHPgaYl8IegcnrhaEUmcjC3bsCuWSwc7PAUdqoQ78SlW+ERyacZrv6QOh E9+7kFyRdE7mpDtH0Z1yQKuR1m8J07glTMHtNjVBtuHeoQYVQFsJhfcPD9Zt66Q7SFqe /34ts4qxVxFdb8tQQfhehHrEOpjd/vzPwrEwpJ6+1l8psaJ4vH2GDlArRnkIvLPN4H6r 478g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772913267; x=1773518067; h=in-reply-to:references:from:to:cc:subject:message-id:date :content-transfer-encoding:mime-version:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=wRapRrMQzfVb1zc8bjuWvKtij1EZN6NyZd+CGQgeUqY=; b=Y6OlRk/tRxzCJBYBxfqUPDWt6KIyhHCfUJAoeZIbwhAEOo1gTRXPsG/hkyB4WGxVYt V6ZmCgzJn3Tyg6G0CxcbV3Wp/fM2/ME5wBBO33vrdlzbw71VE1D/R1pIu3MbHBgUeIA0 MYNmpGpECrytFx/qkshuDyXqnl06rRfqGeQQpBfu+MTSi4tQlvMK1zB8vVQmFsFtspeF UQeVUjsOzyDcMGNhAk35NfVi3l4pYd5p1RR1w5dxvOFhLvwIRcE1Y8xA89CHWkEExTZn HS8EUsizw6Ag74qzPcqdbFZUorNoOrn1Y13Kfi3MWhDikuhib63ayuV9kqW9yWgs3/WA X5Pg== X-Forwarded-Encrypted: i=1; AJvYcCU9h2qeYxYW1l4mJDNcEBkUuGLQyieG+7p9AiEW2sN9CZ2T4gDzUclBUTOIwZEFi+tzUYtT2sH+6tloFW8=@vger.kernel.org X-Gm-Message-State: AOJu0Ywx1dUdOhDK84JdHL0rtCmT3f8H4UcUi+Re3te8GEuH0nzzn4h0 q1IpXoRQCeukDvvyHtN+wyoKPXifn8TfTspfWGXP+yiwXhdsaU+q4lNFhefxBXAe/fU= X-Gm-Gg: ATEYQzyjlFaa3pIx6kKsX/+W221t/BTG9NoKTQASonEwMemA6nwZpoZX2HT7gDFHyuI Ulahn1rZWMKpRgQ+BNdiO2YfFjVf72QIIwvFfzYAb06vkGcF05CAzDUp9T4SjcQCbp2X4v9G2K0 x6v4xfroh+cOqcrUpjcVPiCFjdI6+F8VdVGgBeBkiGiqSNytFfnJf66CZJwXjGOz6A/iL7A6/QY o4PaF2gJTpBy1DXzi6wbRGoi6bRHUQKRsupxculTmKuDTiFrjGlmc/tZ1I3BZ6XuvtZi8MjJzXf 6dsGEMVs5tiSv2f+PJgGOKuAcPlekuNdpB/kyeAddjdTpK2kinUz21qwDb5gruVS2FwkrUNUGlN mS9YqYwJQTZ8Mv2FLoRSNpKcWNEvsTTH5aEoRSTfbkttS51Q+TPDOWZXZ0efLPxIvQHGCnDm7uj 1+efX1shzJiQ== X-Received: by 2002:a05:600c:3e0b:b0:47d:52ef:c572 with SMTP id 5b1f17b1804b1-4851ee6a3fcmr176036785e9.1.1772913267309; Sat, 07 Mar 2026 11:54:27 -0800 (PST) Received: from localhost ([189.99.238.164]) by smtp.gmail.com with ESMTPSA id a1e0cc1a2514c-94e7b57ec19sm5145450241.14.2026.03.07.11.54.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 07 Mar 2026 11:54:26 -0800 (PST) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Sat, 07 Mar 2026 16:54:22 -0300 Message-Id: Subject: Re: [PATCH net v3 2/3] bpf: bpf_out_neigh_v6: Fix nd_tbl NULL dereference when IPv6 is disabled Cc: =?utf-8?b?UmljYXJkbyBCLiBNYXJsacOocmU=?= , "Martin KaFai Lau" , "Daniel Borkmann" , "John Fastabend" , "Stanislav Fomichev" , "Alexei Starovoitov" , "Andrii Nakryiko" , "Eduard Zingerman" , "Song Liu" , "Yonghong Song" , "KP Singh" , "Hao Luo" , "Jiri Olsa" , "David S. Miller" , "Eric Dumazet" , "Paolo Abeni" , "Simon Horman" , =?utf-8?q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , "David Ahern" , "Jay Vosburgh" , "Andrew Lunn" , "Hangbin Liu" , , , To: "Fernando Fernandez Mancera" , "Jakub Kicinski" From: =?utf-8?b?UmljYXJkbyBCLiBNYXJsacOocmU=?= X-Mailer: aerc 0.21.0-120-g0a16d1784be2 References: <20260305-net-nd_tbl_fixes-v3-0-fde28b30a744@suse.com> <20260305-net-nd_tbl_fixes-v3-2-fde28b30a744@suse.com> <20260305182521.0ca7313c@kernel.org> <20260306183914.4b13a03d@kernel.org> <691d5589-46ea-4947-9510-bfd9d991ed02@suse.de> In-Reply-To: <691d5589-46ea-4947-9510-bfd9d991ed02@suse.de> On Sat Mar 7, 2026 at 4:27 AM -03, Fernando Fernandez Mancera wrote: > On 3/7/26 3:39 AM, Jakub Kicinski wrote: >> On Fri, 6 Mar 2026 10:58:44 +0100 Fernando Fernandez Mancera wrote: >>>>> + if (unlikely(!ipv6_stub->nd_tbl)) >>>>> + goto out_drop; >>>> >>>> So neither Fernando nor you checked whether this code can be built >>>> as a module? ipv6_mod_enabled() should work just fine >>> >>> I checked it. If IPV6=3Dm this is not fine. >>> >>> ld: vmlinux.o: in function `bpf_out_neigh_v6': >>> filter.c:(.text+0x3231d60): undefined reference to `ipv6_mod_enabled' >>=20 >> Guess I got it backwards :/ Should we add this to the series? >>=20 Nice, thank you! > > No worries. > >> -->8-------- >> Subject: ipv6: move the disable_ipv6_mod knob to core code >>=20 >> Make sure disable_ipv6_mod itself is not part of the IPv6 module, >> in case core code wants to refer to it. We will remove support >> for IPv6=3Dm soon, this change helps make fixes we commit before >> that less messy. >>=20 >> Signed-off-by: Jakub Kicinski >> --- > > Ricardo could you add it and check if it is fine? FWIW; I am sending=20 > today the series removing IPV6=3Dm after some testing to net-next tree. Will do! > > Thanks, > Fernando. > >> include/linux/ipv6.h | 7 ++++++- >> net/ipv4/af_inet.c | 6 ++++++ >> net/ipv6/af_inet6.c | 8 -------- >> 3 files changed, 12 insertions(+), 9 deletions(-) >>=20 >> diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h >> index 443053a76dcf..e5b6853d517a 100644 >> --- a/include/linux/ipv6.h >> +++ b/include/linux/ipv6.h >> @@ -333,7 +333,12 @@ struct tcp6_timewait_sock { >> }; >> =20 >> #if IS_ENABLED(CONFIG_IPV6) >> -bool ipv6_mod_enabled(void); >> +extern int disable_ipv6_mod; >> + >> +static inline bool ipv6_mod_enabled(void) >> +{ >> + return disable_ipv6_mod =3D=3D 0; >> +} >> =20 >> static inline struct ipv6_pinfo *inet6_sk(const struct sock *__sk) >> { >> diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c >> index babcd75a08e2..f1944e8fd9d3 100644 >> --- a/net/ipv4/af_inet.c >> +++ b/net/ipv4/af_inet.c >> @@ -124,6 +124,12 @@ >> =20 >> #include >> =20 >> +/* Keep the definition of IPv6 disable here for now, to avoid annoying = linker >> + * issues in case IPv6=3Dm >> + */ >> +int disable_ipv6_mod; >> +EXPORT_SYMBOL(disable_ipv6_mod); >> + >> /* The inetsw table contains everything that inet_create needs to >> * build a new socket. >> */ >> diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c >> index 0b995a961359..03c175cbbdb6 100644 >> --- a/net/ipv6/af_inet6.c >> +++ b/net/ipv6/af_inet6.c >> @@ -86,8 +86,6 @@ struct ipv6_params ipv6_defaults =3D { >> .autoconf =3D 1, >> }; >> =20 >> -static int disable_ipv6_mod; >> - >> module_param_named(disable, disable_ipv6_mod, int, 0444); >> MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-fun= ctional"); >> =20 >> @@ -97,12 +95,6 @@ MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all i= nterfaces"); >> module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444); >> MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on a= ll interfaces"); >> =20 >> -bool ipv6_mod_enabled(void) >> -{ >> - return disable_ipv6_mod =3D=3D 0; >> -} >> -EXPORT_SYMBOL_GPL(ipv6_mod_enabled); >> - >> static struct ipv6_pinfo *inet6_sk_generic(struct sock *sk) >> { >> const int offset =3D sk->sk_prot->ipv6_pinfo_offset;