From patchwork Sat Feb 10 01:16:41 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 13552023 Received: from mail-oi1-f172.google.com (mail-oi1-f172.google.com [209.85.167.172]) (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 38F983FD4 for ; Sat, 10 Feb 2024 01:16:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707527809; cv=none; b=ngz0VPygICqILD+f13Ewz1dDzCYu1qSL2Yw/+I+SGB2+h0eac77R+Yf+MrgtzC5SmEfNwt6KOsKrMIroWzuttQbPBi7IbTrbb7tb2A06pHEyyocnD0OnjRriTbl4OVyZSYtUU2UzMi5o0CvJOLY/LzUdD3w+rzYXUxxSG2EjVRA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707527809; c=relaxed/simple; bh=UIYu98yTnq6IoG7p77xS2jBpkcg5lQjLVhPitCGvuaQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=kgxmotuQOc/SEZGnVo+uFP5p/19MwEK8RSSMyWF2SDd923bNU125g3h8uPhSqpDDCNOvUGCR3e8/aje2vc0QgmI0TtXYPwJNsmampcGYDvvEpyqsTL30WwCUROCOtAGUwS6nF3FiShbYsW0c8LZoOmHEm+6elQKakK1UCg5XwiQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=aV2T8cIw; arc=none smtp.client-ip=209.85.167.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="aV2T8cIw" Received: by mail-oi1-f172.google.com with SMTP id 5614622812f47-3bfff8c4b94so486999b6e.2 for ; Fri, 09 Feb 2024 17:16:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1707527807; x=1708132607; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=3Ze5Pa4NcSME/+yvLBfrb6tRG6ghxrx7Dfdjk9njymg=; b=aV2T8cIw3DOHGt4SuipZaxVPBB2seJ/i0KZIvbBECJd65MJauEM4Wb6FpyKljfseA9 HCOvNcmK72i6wwzzXXPhomTaNZRPaUicWtC9OPKI7LgsI91KjMdgUj2oxaPAJTz4nimG zScCKp5nSrQM0ypNQqE3s3fHGPYRaGlA9n5JI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707527807; x=1708132607; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3Ze5Pa4NcSME/+yvLBfrb6tRG6ghxrx7Dfdjk9njymg=; b=fPZAtNYH4MscTkWfrLGxaqkRfzCf6qUy7TviQSC5EoZImPSfWN96H1zl4N76sGeWvw +oW2bc1ncweedkLGkjh+5X0DiAIR+yNlk+h6WUBXTwIykf/sImUrn5ZyPznwk0MtB4dO DWijTKdkij/2z/o/KI4dPRVxVocHhmX/EeA4F16toWH8Lv77T7QGy/Zt3lcMs8Q91w0x YS5bU+Xy9EHGXn9eOUORLN9D33eprvyGA8QD21Ob15mlkuWevGmqOJHqc/kpysC5goyj eWNSmahcxncLIF4l1cZtkL9kzKeVeWqa3H9konvBq2exqIDA5rQfwI/JfhFMgG36Dgdi EzUA== X-Forwarded-Encrypted: i=1; AJvYcCXaM+Q8Q/zrvM3eTsXPr0gWpmRVTZkL0+Im90wRGsSO2Z1k/qWPPEpMqirrRaWWWDv+N9hbsquoK0eHgNlsvKhxZOFpAj1i X-Gm-Message-State: AOJu0YzTTAIMHXBAB+xgGdvIvP4GTux4QNBX/Poe+nfkQPNc5iWkY8oh FZPtB+SGhsh3CB530c4sBmQEI5BfsjEn1r5zyxdRt2HA+e/RtLOD02eqDTjtVA== X-Google-Smtp-Source: AGHT+IEKi1eEOSwMW3MpZVRb38CcWUA4s3Gb7uYAM3HsK8HkoIO5prwyulds2tpc/QtITjI/gewPkQ== X-Received: by 2002:a05:6870:d154:b0:214:9ce3:ed2b with SMTP id f20-20020a056870d15400b002149ce3ed2bmr1021019oac.41.1707527807338; Fri, 09 Feb 2024 17:16:47 -0800 (PST) X-Forwarded-Encrypted: i=1; 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 Received: from www.outflux.net ([198.0.35.241]) by smtp.gmail.com with ESMTPSA id c125-20020a633583000000b005dc4da2121fsm2481005pga.6.2024.02.09.17.16.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Feb 2024 17:16:44 -0800 (PST) From: Kees Cook To: Jakub Kicinski Cc: Kees Cook , "Gustavo A . R . Silva" , Rasmus Villemoes , Dan Williams , Keith Packard , Miguel Ojeda , Alexey Dobriyan , Dmitry Antipov , "David S. Miller" , Eric Dumazet , Paolo Abeni , Nathan Chancellor , kernel test robot , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH 1/2] stddef: Allow attributes to be used when creating flex arrays Date: Fri, 9 Feb 2024 17:16:41 -0800 Message-Id: <20240210011643.1706285-1-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240210011452.work.985-kees@kernel.org> References: <20240210011452.work.985-kees@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3916; i=keescook@chromium.org; h=from:subject; bh=UIYu98yTnq6IoG7p77xS2jBpkcg5lQjLVhPitCGvuaQ=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBlxs565KmSp3fQbXTcJwGQKFvGMK3wEqdmQ7/xb uTx0bjHKlCJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCZcbOegAKCRCJcvTf3G3A JhaYD/9JDBbI/XgOae54dbshjDoJ76Ha6DpLzDux/EAHjpeJ1+scXgSkqee2gAfC/wb9DvS1fgS 0deWCT0upE1Hv3YKcPr6aUv6nqbRTffqCDL1aX/TPdqBPNA1LSXPQFJj9fQJ8qtaJy90yivafd/ /luFZAr+qRIcKjRq2CJRmrknxXSIJD4kmI37X+9U2bG74t+XQuTOHeH4m47l5xMorFT5Njg+Emt Zr/Ls/vfK9KojTi7tirVLSLtHdJruvQtc3TXRAzsnv/UTeimSYzBlwxTN2dTeuCfjXdWe1MrncV UrAzhMcRtsUub7GAE3awCB8nX6FQaH1q8DCHrv3vpzVuboHBzOsSmYUbvO/9gMSr3rXqYO2FCR6 GtG+OP9DfWZmf8zCVLcWDsHy0qv5mUAXL5TUMyxR4REILeuHI65nhyxnGFZy+aC3zq35A/qJ7bm EcZPQy4GbvlKuvgEAIksnBOIJryiQkxWj/PvZAyIjPMEC6ttj2QRccFx6XhcOgHxtumDESQShik lJ1dk3K+ru9HaA2RDQ5ikQpn4IDFiItrGzuT4Z5NigIdlRcbdWKiTjt7+v2quTN9ZzQYQ+hA8pU t+0mGm+YTF7UOD23q10V/9LCAuGlhP1T7WMFc1/3H+Xui4Ljpd0BZV0i4jpfAEh7XreSEDWl1ep 5z3ELwYLKxghsYQ== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 With the coming support for the __counted_by struct member attribute, we will need a way to add such annotations to the places where DECLARE_FLEX_ARRAY() is used. Introduce DECLARE_FLEX_ARRAY_ATTR() which takes a third argument: the attributes to apply to the flexible array. Cc: Gustavo A. R. Silva Cc: Rasmus Villemoes Cc: Dan Williams Cc: Keith Packard Cc: Miguel Ojeda Cc: Alexey Dobriyan Cc: Dmitry Antipov Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva --- include/linux/stddef.h | 16 ++++++++++++++-- include/uapi/linux/stddef.h | 25 +++++++++++++++++++------ 2 files changed, 33 insertions(+), 8 deletions(-) diff --git a/include/linux/stddef.h b/include/linux/stddef.h index 929d67710cc5..eb51f6727ecf 100644 --- a/include/linux/stddef.h +++ b/include/linux/stddef.h @@ -81,8 +81,20 @@ enum { __struct_group(TAG, NAME, /* no attrs */, MEMBERS) /** - * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * DECLARE_FLEX_ARRAY_ATTR() - Declare a flexible array usable in a union + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * @ATTRS: The list of member attributes to apply * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) + +/** + * DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union * @TYPE: The type of each flexible array element * @NAME: The name of the flexible array member * @@ -91,6 +103,6 @@ enum { * named member, but that member can be empty. */ #define DECLARE_FLEX_ARRAY(TYPE, NAME) \ - __DECLARE_FLEX_ARRAY(TYPE, NAME) + DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #endif diff --git a/include/uapi/linux/stddef.h b/include/uapi/linux/stddef.h index 2ec6f35cda32..5499c08ad011 100644 --- a/include/uapi/linux/stddef.h +++ b/include/uapi/linux/stddef.h @@ -31,24 +31,37 @@ #ifdef __cplusplus /* sizeof(struct{}) is 1 in C++, not 0, can't use C version of the macro. */ -#define __DECLARE_FLEX_ARRAY(T, member) \ - T member[0] +#define __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ + TYPE NAME[0] ATTRS +#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #else /** - * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union - * + * __DECLARE_FLEX_ARRAY_ATTR() - Declare a flexible array usable in a union * @TYPE: The type of each flexible array element * @NAME: The name of the flexible array member + * @ATTRS: The list of member attributes to apply * * In order to have a flexible array member in a union or alone in a * struct, it needs to be wrapped in an anonymous struct with at least 1 * named member, but that member can be empty. */ -#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ +#define __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, ATTRS) \ struct { \ struct { } __empty_ ## NAME; \ - TYPE NAME[]; \ + TYPE NAME[] ATTRS; \ } +/** + * __DECLARE_FLEX_ARRAY() - Declare a flexible array usable in a union + * @TYPE: The type of each flexible array element + * @NAME: The name of the flexible array member + * + * In order to have a flexible array member in a union or alone in a + * struct, it needs to be wrapped in an anonymous struct with at least 1 + * named member, but that member can be empty. + */ +#define __DECLARE_FLEX_ARRAY(TYPE, NAME) \ + __DECLARE_FLEX_ARRAY_ATTR(TYPE, NAME, /* no attributes */) #endif #ifndef __counted_by