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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 4DC82C433DB for ; Mon, 8 Feb 2021 18:01:03 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D78CB64E7D for ; Mon, 8 Feb 2021 18:01:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D78CB64E7D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=1ou3SS0XSyP+3l/zT5C3pAF51cmQPiJZivkbqWWrecg=; b=DvbHV/PEEykw1Z0AHL6YjPrSO HMA3/5i3wsEu0LBfH+H/1RQlsp5SqWaHAfA6Z/zyZQ6tZmOq9Z65xK+FgVJLDCm/NSniRotOYPY5j FRQ/qwtPxaqHIeNOewKdT8ZWJvfSZxNooigvSonorZlj8udNB9TUUzCxWeIcONo8RUysG6dlMNjvj /JbSp2c+it8UyFK7Ywf4iNughM7VR8mG1TqI/uv+ezrsNhbSXAgZ512ybTQ8vQ1cYhlSWOSoJclbI 9rct7zS2pslWtI7BY9PxTWfUrREtXurApEZ0aMqrIa6XPeJaCbg7cwT+nBI2Eh0CoWV3BNLjTbaXt G64/AJ9SQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9Aow-0007Hd-Jn; Mon, 08 Feb 2021 17:59:34 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l9AoD-0006rY-2l for linux-arm-kernel@lists.infradead.org; Mon, 08 Feb 2021 17:58:53 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1C67B64ECD; Mon, 8 Feb 2021 17:58:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612807127; bh=ft4G97VhIjJwaES8UFkwK1Ab7kaT0oqcang245BltCQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hOkVzrCQhj4GUHh7tPRK90Gp0bzA07PDFzoqV7AyMTEzO2JdAGkKASkRX8cYv6Pe/ 97gwCYe+o/Wo9ljzW9uhO1SZemp7y/gdN6z4sWK9OCg/64F58OpeEMnqBMc5dtCdwV QE6VO4Kc8k5pIlPsGP/qLOuKSG9MXVKtHyIWRpd9lFnI4SEZ9n935klmEnsojqrAr8 Z0lA7Bdi4JHNLju8ipu+PeEuM14WZhAA2DHFI3eEIz8Nvk/UAYZly66v2He5iDoE+S IM+IedzLgySbw5a/AuVoWMIX4Idx0TlcuvW+eon9O+mjIV4ItzR/WB8Vm9A3R1PlUl g/eTHobU3Y5nw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.10 30/36] ARM: ensure the signal page contains defined contents Date: Mon, 8 Feb 2021 12:58:00 -0500 Message-Id: <20210208175806.2091668-30-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210208175806.2091668-1-sashal@kernel.org> References: <20210208175806.2091668-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210208_125849_473502_0690D4C5 X-CRM114-Status: GOOD ( 12.50 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , Russell King , Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Russell King [ Upstream commit 9c698bff66ab4914bb3d71da7dc6112519bde23e ] Ensure that the signal page contains our poison instruction to increase the protection against ROP attacks and also contains well defined contents. Acked-by: Will Deacon Signed-off-by: Russell King Signed-off-by: Sasha Levin --- arch/arm/kernel/signal.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 585edbfccf6df..2f81d3af5f9af 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -693,18 +693,20 @@ struct page *get_signal_page(void) addr = page_address(page); + /* Poison the entire page */ + memset32(addr, __opcode_to_mem_arm(0xe7fddef1), + PAGE_SIZE / sizeof(u32)); + /* Give the signal return code some randomness */ offset = 0x200 + (get_random_int() & 0x7fc); signal_return_offset = offset; - /* - * Copy signal return handlers into the vector page, and - * set sigreturn to be a pointer to these. - */ + /* Copy signal return handlers into the page */ memcpy(addr + offset, sigreturn_codes, sizeof(sigreturn_codes)); - ptr = (unsigned long)addr + offset; - flush_icache_range(ptr, ptr + sizeof(sigreturn_codes)); + /* Flush out all instructions in this page */ + ptr = (unsigned long)addr; + flush_icache_range(ptr, ptr + PAGE_SIZE); return page; } -- 2.27.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel