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 X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB18BC2BBCD for ; Wed, 16 Dec 2020 04:44:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80EB72313F for ; Wed, 16 Dec 2020 04:44:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725881AbgLPEoP (ORCPT ); Tue, 15 Dec 2020 23:44:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:49704 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725874AbgLPEoP (ORCPT ); Tue, 15 Dec 2020 23:44:15 -0500 Date: Tue, 15 Dec 2020 20:43:07 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1608093788; bh=1k7VqyyUZbR3M+tfaIAckOATam0jAq+vTTRRI3L3bzQ=; h=From:To:Subject:In-Reply-To:From; b=R6arNDs2vZvId+IgwAAUAy5XNuBb8BixaXobiTEyEIaRzrPveWl53nIuTDr6UdHra YxkBxsOhkdwVAXwue7zjy4crJN4nakwZrkYVAtD4TT/U+JRvkr92OSKKSd9aiCTvuI dJ3BMbq9xCGt3HPDMnFA7bSR0br9RPkM5wbiIw1o= From: Andrew Morton To: akpm@linux-foundation.org, gustavoars@kernel.org, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 15/95] lib/stackdepot.c: use flex_array_size() helper in memcpy() Message-ID: <20201216044307.Qzi6xASDs%akpm@linux-foundation.org> In-Reply-To: <20201215204156.f05ec694b907845bcfab5c44@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: "Gustavo A. R. Silva" Subject: lib/stackdepot.c: use flex_array_size() helper in memcpy() Make use of the flex_array_size() helper to calculate the size of a flexible array member within an enclosing structure. This helper offers defense-in-depth against potential integer overflows, while at the same time makes it explicitly clear that we are dealing with a flexible array member. Link: https://lkml.kernel.org/r/186e37fe07196ee41a0e562fa8a8cb7a01112ec5.1601565471.git.gustavoars@kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Andrew Morton --- lib/stackdepot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/lib/stackdepot.c~lib-stackdepotc-use-flex_array_size-helper-in-memcpy +++ a/lib/stackdepot.c @@ -135,7 +135,7 @@ static struct stack_record *depot_alloc_ stack->handle.slabindex = depot_index; stack->handle.offset = depot_offset >> STACK_ALLOC_ALIGN; stack->handle.valid = 1; - memcpy(stack->entries, entries, size * sizeof(unsigned long)); + memcpy(stack->entries, entries, flex_array_size(stack, entries, size)); depot_offset += required_size; return stack; _