From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 81EEDC54798 for ; Tue, 5 Mar 2024 19:58:49 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=NJjY8iz0; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Tq5wl6bQGz3dXX for ; Wed, 6 Mar 2024 06:58:47 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=NJjY8iz0; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=2604:1380:4641:c500::1; helo=dfw.source.kernel.org; envelope-from=gustavoars@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Tq5vw0Dxkz3d2j for ; Wed, 6 Mar 2024 06:58:03 +1100 (AEDT) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 079C0617C9; Tue, 5 Mar 2024 19:58:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B3A0C433C7; Tue, 5 Mar 2024 19:57:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1709668679; bh=rNMn2F0pebCQ/PygWwODGmBr/a9yxmXD0UeqpVN1H0Q=; h=Date:From:To:Cc:Subject:From; b=NJjY8iz0KVr4KZyCQYfXEhTBa2fC97LgEopVwE00q7YpN91Iu+3ETp+DTDf0e4cuC ZPPvBCYxqlcVPp/m/f1hw3YXoH/6X+Eg0BZ8bjjfiVaOEY5lmUOeVu5CMHhuQ755bc 6RAFRCboyzMjdjjzvXvZizEpB57HNRQdytpIyYtScjTspW2J5YT57how0cawvnSJ5o J1U/whwqlHFKYn9ZIoxt+Nz3rqAQEIj2ShxBs000QrQuxLiDV8FNCEllsJtb4w2H/n 9/pbhI0yb/pXY9DyekiOfEvrMgBs0Tv5BruUCbFN0qRJQ2bDJicvygkuZfEof84rNT CNswwlAQcCzfw== Date: Tue, 5 Mar 2024 13:57:56 -0600 From: "Gustavo A. R. Silva" To: Haren Myneni , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "Aneesh Kumar K.V" , "Naveen N. Rao" , Herbert Xu , "David S. Miller" Subject: [PATCH][next] crypto/nx: Avoid -Wflex-array-member-not-at-end warning Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kees Cook , "Gustavo A. R. Silva" , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-crypto@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" -Wflex-array-member-not-at-end is coming in GCC-14, and we are getting ready to enable it globally. So, we are deprecating flexible-array members in the middle of another structure. There is currently an object (`header`) in `struct nx842_crypto_ctx` that contains a flexible structure (`struct nx842_crypto_header`): struct nx842_crypto_ctx { ... struct nx842_crypto_header header; struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX]; ... }; So, in order to avoid ending up with a flexible-array member in the middle of another struct, we use the `struct_group_tagged()` helper to separate the flexible array from the rest of the members in the flexible structure: struct nx842_crypto_header { struct_group_tagged(nx842_crypto_header_hdr, hdr, ... the rest of the members ); struct nx842_crypto_header_group group[]; } __packed; With the change described above, we can now declare an object of the type of the tagged struct, without embedding the flexible array in the middle of another struct: struct nx842_crypto_ctx { ... struct nx842_crypto_header_hdr header; struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX]; ... } __packed; We also use `container_of()` whenever we need to retrieve a pointer to the flexible structure, through which we can access the flexible array if needed. So, with these changes, fix the following warning: In file included from drivers/crypto/nx/nx-842.c:55: drivers/crypto/nx/nx-842.h:174:36: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] 174 | struct nx842_crypto_header header; | ^~~~~~ Signed-off-by: Gustavo A. R. Silva --- drivers/crypto/nx/nx-842.c | 6 ++++-- drivers/crypto/nx/nx-842.h | 10 ++++++---- 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/crypto/nx/nx-842.c b/drivers/crypto/nx/nx-842.c index 2ab90ec10e61..82214cde2bcd 100644 --- a/drivers/crypto/nx/nx-842.c +++ b/drivers/crypto/nx/nx-842.c @@ -251,7 +251,9 @@ int nx842_crypto_compress(struct crypto_tfm *tfm, u8 *dst, unsigned int *dlen) { struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm); - struct nx842_crypto_header *hdr = &ctx->header; + struct nx842_crypto_header *hdr = + container_of(&ctx->header, + struct nx842_crypto_header, hdr); struct nx842_crypto_param p; struct nx842_constraints c = *ctx->driver->constraints; unsigned int groups, hdrsize, h; @@ -490,7 +492,7 @@ int nx842_crypto_decompress(struct crypto_tfm *tfm, } memcpy(&ctx->header, src, hdr_len); - hdr = &ctx->header; + hdr = container_of(&ctx->header, struct nx842_crypto_header, hdr); for (n = 0; n < hdr->groups; n++) { /* ignore applies to last group */ diff --git a/drivers/crypto/nx/nx-842.h b/drivers/crypto/nx/nx-842.h index 7590bfb24d79..25fa70b2112c 100644 --- a/drivers/crypto/nx/nx-842.h +++ b/drivers/crypto/nx/nx-842.h @@ -157,9 +157,11 @@ struct nx842_crypto_header_group { } __packed; struct nx842_crypto_header { - __be16 magic; /* NX842_CRYPTO_MAGIC */ - __be16 ignore; /* decompressed end bytes to ignore */ - u8 groups; /* total groups in this header */ + struct_group_tagged(nx842_crypto_header_hdr, hdr, + __be16 magic; /* NX842_CRYPTO_MAGIC */ + __be16 ignore; /* decompressed end bytes to ignore */ + u8 groups; /* total groups in this header */ + ); struct nx842_crypto_header_group group[]; } __packed; @@ -171,7 +173,7 @@ struct nx842_crypto_ctx { u8 *wmem; u8 *sbounce, *dbounce; - struct nx842_crypto_header header; + struct nx842_crypto_header_hdr header; struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX]; struct nx842_driver *driver; -- 2.34.1