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 3A4C46FAF; Tue, 5 Dec 2023 03:23:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="o+SGvYWK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E85CC433C8; Tue, 5 Dec 2023 03:23:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1701746609; bh=tzgfKl/DcFVAUrqG/LrzbQL3yneTGRA7Uz4bFt62qzI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=o+SGvYWKvLnQdMKyfxbs3JH2KhKE/l/ge7DmijCX/TWcRCKenO2DOp6ESLsrP7d0q wKvZ572e2oUJExNkHttQxLvehyLo+KZrQptNYl5FgEbEHp3KHl8Zc9RHVXrD4/iprF lFioN4w0m7vUaDGejDVjzmIBEJMV8AgjnvQoLLSo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, kernel test robot , Dmitry Antipov , Kees Cook , Sasha Levin Subject: [PATCH 6.6 090/134] uapi: propagate __struct_group() attributes to the container union Date: Tue, 5 Dec 2023 12:16:02 +0900 Message-ID: <20231205031541.153920591@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231205031535.163661217@linuxfoundation.org> References: <20231205031535.163661217@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Antipov [ Upstream commit 4e86f32a13af1970d21be94f659cae56bbe487ee ] Recently the kernel test robot has reported an ARM-specific BUILD_BUG_ON() in an old and unmaintained wil6210 wireless driver. The problem comes from the structure packing rules of old ARM ABI ('-mabi=apcs-gnu'). For example, the following structure is packed to 18 bytes instead of 16: struct poorly_packed { unsigned int a; unsigned int b; unsigned short c; union { struct { unsigned short d; unsigned int e; } __attribute__((packed)); struct { unsigned short d; unsigned int e; } __attribute__((packed)) inner; }; } __attribute__((packed)); To fit it into 16 bytes, it's required to add packed attribute to the container union as well: struct poorly_packed { unsigned int a; unsigned int b; unsigned short c; union { struct { unsigned short d; unsigned int e; } __attribute__((packed)); struct { unsigned short d; unsigned int e; } __attribute__((packed)) inner; } __attribute__((packed)); } __attribute__((packed)); Thanks to Andrew Pinski of GCC team for sorting the things out at https://gcc.gnu.org/pipermail/gcc/2023-November/242888.html. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202311150821.cI4yciFE-lkp@intel.com Signed-off-by: Dmitry Antipov Link: https://lore.kernel.org/r/20231120110607.98956-1-dmantipov@yandex.ru Fixes: 50d7bd38c3aa ("stddef: Introduce struct_group() helper macro") Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- include/uapi/linux/stddef.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/uapi/linux/stddef.h b/include/uapi/linux/stddef.h index 5c6c4269f7efe..2ec6f35cda32e 100644 --- a/include/uapi/linux/stddef.h +++ b/include/uapi/linux/stddef.h @@ -27,7 +27,7 @@ union { \ struct { MEMBERS } ATTRS; \ struct TAG { MEMBERS } ATTRS NAME; \ - } + } ATTRS #ifdef __cplusplus /* sizeof(struct{}) is 1 in C++, not 0, can't use C version of the macro. */ -- 2.42.0