From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1B01B1C1AAA; Tue, 14 Jan 2025 18:32:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736879580; cv=none; b=YWfkfH2TbAdcz+t+hWWXVMXb6Ogl2KpVsFx3/jnfHy5v1QQV/qUtMs3xTXYbsT1zLP56gjRysRt0JJ0m+h4rSdB3amdtBniQNMtscYA03eLLcovQI/SNtrAAQFuQCO65Lx8RC7qrprygF0X/sjKuHPiJk8v8MBALm5DWH3dXmnI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736879580; c=relaxed/simple; bh=+VYfghA8rdZLLpmdod8238HnaaeOZHNazblnDuKrS5A=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Tfw1sgkd/zQudNdAJKBBjh/gRNQHZUrMi2Q0aG3BPwNkAjBqdOqXhz+GSIsNnctFaLo6dYDkMmsN8S06pd51yc7xo+ZJ0QPUtOXLLuzTk3EZ6lTlyXhubIgr2aCw+e83pYH21fWMppxe020fj3ENwDHF4yPDx51RGi5HijJnoEo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dTSufW4e; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dTSufW4e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4505C4CEDD; Tue, 14 Jan 2025 18:32:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736879579; bh=+VYfghA8rdZLLpmdod8238HnaaeOZHNazblnDuKrS5A=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=dTSufW4efKR+RIHqvwO/9tgIApbDDjdv44InVf79nTpH+fqsZoocULrcrwKMVnQQ5 RdzKW96/aFBeiCxYXTefWPYIICbm+Eu6rG7ovKW+JdGiRI47459qzUvUXDQhCB2gRM 701k5jFBY4zSmNTziWErYmRGTY/TYyEiiyWUSgUuEkxH3EbunKYRIF0Wa6wGYshwDr MxqJ7pDFS6HDOAkfgpagILog3wKencYyaQQmL7omgH5ezoWMJDVFSItmpitzazhtaO HG+IClazBl+1mEWiDJrI71zrYT1bk7xYW2/7xCY4wqsD1f1YdMI+fhWUJolUp8mxLi UKEpo9Ifnp0yw== Date: Tue, 14 Jan 2025 10:32:57 -0800 From: Jakub Kicinski To: Li Li Cc: Carlos Llamas , dualli@google.com, corbet@lwn.net, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, donald.hunter@gmail.com, gregkh@linuxfoundation.org, arve@android.com, tkjos@android.com, maco@android.com, joel@joelfernandes.org, brauner@kernel.org, surenb@google.com, arnd@arndb.de, masahiroy@kernel.org, bagasdotme@gmail.com, horms@kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, netdev@vger.kernel.org, hridya@google.com, smoreland@google.com, kernel-team@android.com Subject: Re: [PATCH v11 2/2] binder: report txn errors via generic netlink Message-ID: <20250114103257.73e9c0d1@kernel.org> In-Reply-To: References: <20241218203740.4081865-1-dualli@chromium.org> <20241218203740.4081865-3-dualli@chromium.org> <20250109121300.2fc13a94@kernel.org> <20250109161825.62b31b18@kernel.org> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 13 Jan 2025 22:01:00 -0800 Li Li wrote: > On Thu, Jan 9, 2025 at 4:18=E2=80=AFPM Jakub Kicinski w= rote: > > > Sorry, it was me that suggested NETLINK_URELEASE. BTW, I did try those > > > genl_family callbacks first but I couldn't get them to work right away > > > so I moved on. I'll have a closer look now to figure out what I did > > > wrong. Thanks for the suggestion Jakub! =20 > > > > Hm, that's probably because there is no real multicast group here :( > > genl_sk_priv_get() and co. may work better in that case. > > your suggestion of NETLINK_URELEASE may work too, tho, I think it's > > the most error prone =20 >=20 > sock_priv_destroy works with genl_sk_priv_get(). >=20 > But, I have to manually modify the generated netlink header file to satis= fy CFI. >=20 > -void binder_nl_sock_priv_init(struct my_struct *priv); > -void binder_nl_sock_priv_destroy(struct my_struct *priv); > +void binder_nl_sock_priv_init(void *priv); > +void binder_nl_sock_priv_destroy(void *priv); >=20 > The reason is that these 2 callback functions are defined in > include/net/genetlink.h as below > void (*sock_priv_init)(void *priv); > void (*sock_priv_destroy)(void *priv); >=20 > Otherwise, kernel panic when CFI is enabled. >=20 > CFI failure at genl_sk_priv_get+0x60/0x138 (target: > binder_nl_sock_priv_init+0x0/0x34; expected type: 0x0ef81b7d) >=20 > Jakub, we probably need this patch. Please let me know if you have a > better idea. Thanks! >=20 > diff --git a/tools/net/ynl/ynl-gen-c.py b/tools/net/ynl/ynl-gen-c.py > index 8155ff6d2a38..84033938a75f 100755 > --- a/tools/net/ynl/ynl-gen-c.py > +++ b/tools/net/ynl/ynl-gen-c.py > @@ -2352,8 +2352,8 @@ def print_kernel_family_struct_hdr(family, cw): > cw.p(f"extern struct genl_family {family.c_name}_nl_family;") > cw.nl() > if 'sock-priv' in family.kernel_family: > - cw.p(f'void > {family.c_name}_nl_sock_priv_init({family.kernel_family["sock-priv"]} > *priv);') > - cw.p(f'void > {family.c_name}_nl_sock_priv_destroy({family.kernel_family["sock-priv"]} > *priv);') > + cw.p(f'void {family.c_name}_nl_sock_priv_init(void *priv);') > + cw.p(f'void {family.c_name}_nl_sock_priv_destroy(void *priv);') > cw.nl() >=20 Maybe we can codegen a little wrapper call. Can you try this with CFI? ---->8------------ diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen= _c.py index d3a7dfbcf929..9852ba6fd9c3 100755 --- a/tools/net/ynl/pyynl/ynl_gen_c.py +++ b/tools/net/ynl/pyynl/ynl_gen_c.py @@ -2411,6 +2411,15 @@ _C_KW =3D { if not kernel_can_gen_family_struct(family): return =20 + if 'sock-priv' in family.kernel_family: + # Generate "trampolines" to make CFI happy + cw.write_func("static void", f"__{family.c_name}_nl_sock_priv_init= ", + [f"{family.c_name}_nl_sock_priv_init(priv);"], ["voi= d *priv"]) + cw.nl() + cw.write_func("static void", f"__{family.c_name}_nl_sock_priv_dest= roy", + [f"{family.c_name}_nl_sock_priv_destroy(priv);"], ["= void *priv"]) + cw.nl() + cw.block_start(f"struct genl_family {family.ident_name}_nl_family __ro= _after_init =3D") cw.p('.name\t\t=3D ' + family.fam_key + ',') cw.p('.version\t=3D ' + family.ver_key + ',') @@ -2428,9 +2437,8 @@ _C_KW =3D { cw.p(f'.n_mcgrps\t=3D ARRAY_SIZE({family.c_name}_nl_mcgrps),') if 'sock-priv' in family.kernel_family: cw.p(f'.sock_priv_size\t=3D sizeof({family.kernel_family["sock-pri= v"]}),') - # Force cast here, actual helpers take pointer to the real type. - cw.p(f'.sock_priv_init\t=3D (void *){family.c_name}_nl_sock_priv_i= nit,') - cw.p(f'.sock_priv_destroy =3D (void *){family.c_name}_nl_sock_priv= _destroy,') + cw.p(f'.sock_priv_init\t=3D __{family.c_name}_nl_sock_priv_init,') + cw.p(f'.sock_priv_destroy =3D __{family.c_name}_nl_sock_priv_destr= oy,') cw.block_end(';') =20 =20 --=20 2.47.1