From patchwork Wed May 17 01:03:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 13244043 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 081E3C77B7A for ; Wed, 17 May 2023 01:02:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229638AbjEQBCx (ORCPT ); Tue, 16 May 2023 21:02:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229635AbjEQBCx (ORCPT ); Tue, 16 May 2023 21:02:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4557E1BFD; Tue, 16 May 2023 18:02:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DB20264073; Wed, 17 May 2023 01:02:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF893C433EF; Wed, 17 May 2023 01:02:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684285371; bh=nVMhlmmUXfL1NdxdVCdqZzrzgKQ9uLWQHIfd1j3SZzA=; h=Date:From:To:Cc:Subject:From; b=AMP3rdH1zjSserQL0c9yAZPalpvwfhgz/4bMBrVqJE2dS6Ln6f/w24UpmFrinkwaG MOW9rbW8RAsq4t6F+zAId0LrfuI/Fc3EcDNvhMYPjiu+RcI0rbEmkdy7fqZiSRsx6I TQp1QqVq6YAKat7pbiwEp0AvhX2B6xZUB5+9pe2jiQYe+NCJKjK2XhGGpakPwJ2qbr GJQnJRk5u78PDtRIVhh4P8Z0wXTNe37uc5cn8rZsoytD27gs7/ijuQz21G530mkx1u Pd5HjfJJVLAdUxX8a1guhBCKCoeMRuxccDt5LheXXoWdLYXVvR64bnUGEK8QVO2VQQ 5ydG6NC7cR25g== Date: Tue, 16 May 2023 19:03:39 -0600 From: "Gustavo A. R. Silva" To: Stanimir Varbanov , Vikash Garodia , Andy Gross , Bjorn Andersson , Konrad Dybcio , Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org Subject: [PATCH][next] media: venus: hfi_cmds: Replace fake flex-array with flexible-array member Message-ID: MIME-Version: 1.0 Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org One-element arrays are deprecated, and we are replacing them with flexible array members instead. So, replace one-element arrays with flexible-array members in struct hfi_sys_set_resource_pkt, and refactor the rest of the code, accordingly. This helps with the ongoing efforts to tighten the FORTIFY_SOURCE routines on memcpy() and help us make progress towards globally enabling -fstrict-flex-arrays=3 [1]. The only binary differences seen before/after changes are the following: 17ba: mov %rbx,%rdi 17bd: call 17c2 17be: R_X86_64_PLT32 __tsan_write4-0x4 - 17c2: movl $0x14,(%rbx) + 17c2: movl $0x10,(%rbx) 17c8: lea 0x4(%rbx),%rdi 17cc: call 17d1 17cd: R_X86_64_PLT32 __tsan_write4-0x4 which is expected once this accounts for the following line of code at drivers/media/platform/qcom/venus/hfi_cmds.c:73 73 pkt->hdr.size = sizeof(*pkt); and as *pkt is of type struct hfi_sys_set_resource_pkt, sizeof(*pkt) is reduced by 4 bytes, due to the flex-array transformation. Link: https://github.com/KSPP/linux/issues/79 Link: https://github.com/KSPP/linux/issues/293 Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1] Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook --- drivers/media/platform/qcom/venus/hfi_cmds.c | 2 +- drivers/media/platform/qcom/venus/hfi_cmds.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/qcom/venus/hfi_cmds.c b/drivers/media/platform/qcom/venus/hfi_cmds.c index 3f74d518ad08..7c82e212434e 100644 --- a/drivers/media/platform/qcom/venus/hfi_cmds.c +++ b/drivers/media/platform/qcom/venus/hfi_cmds.c @@ -83,7 +83,7 @@ int pkt_sys_set_resource(struct hfi_sys_set_resource_pkt *pkt, u32 id, u32 size, res->size = size; res->mem = addr; pkt->resource_type = HFI_RESOURCE_OCMEM; - pkt->hdr.size += sizeof(*res) - sizeof(u32); + pkt->hdr.size += sizeof(*res); break; } case VIDC_RESOURCE_NONE: diff --git a/drivers/media/platform/qcom/venus/hfi_cmds.h b/drivers/media/platform/qcom/venus/hfi_cmds.h index ba74d03eb9cd..dd9c5066442d 100644 --- a/drivers/media/platform/qcom/venus/hfi_cmds.h +++ b/drivers/media/platform/qcom/venus/hfi_cmds.h @@ -56,7 +56,7 @@ struct hfi_sys_set_resource_pkt { struct hfi_pkt_hdr hdr; u32 resource_handle; u32 resource_type; - u32 resource_data[1]; + u32 resource_data[]; }; struct hfi_sys_release_resource_pkt {