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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 8A37BC433DB for ; Wed, 3 Feb 2021 12:12:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 431A464E46 for ; Wed, 3 Feb 2021 12:12:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234478AbhBCMMl (ORCPT ); Wed, 3 Feb 2021 07:12:41 -0500 Received: from mail.kernel.org ([198.145.29.99]:55486 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234394AbhBCMMk (ORCPT ); Wed, 3 Feb 2021 07:12:40 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 85D0F64F74; Wed, 3 Feb 2021 12:11:58 +0000 (UTC) From: Catalin Marinas To: Greg Kroah-Hartman Cc: , Vincenzo Frascino , Will Deacon Subject: [PATCH stable 5.4.x] arm64: Fix kernel address detection of __is_lm_address() Date: Wed, 3 Feb 2021 12:11:56 +0000 Message-Id: <20210203121156.29684-1-catalin.marinas@arm.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vincenzo Frascino commit 519ea6f1c82fcdc9842908155ae379de47818778 upstream. Currently, the __is_lm_address() check just masks out the top 12 bits of the address, but if they are 0, it still yields a true result. This has as a side effect that virt_addr_valid() returns true even for invalid virtual addresses (e.g. 0x0). Fix the detection checking that it's actually a kernel address starting at PAGE_OFFSET. Fixes: 68dd8ef32162 ("arm64: memory: Fix virt_addr_valid() using __is_lm_address()") Cc: # 5.4.x Cc: Will Deacon Suggested-by: Catalin Marinas Reviewed-by: Catalin Marinas Acked-by: Mark Rutland Signed-off-by: Vincenzo Frascino Link: https://lore.kernel.org/r/20210126134056.45747-1-vincenzo.frascino@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/memory.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 51d867cf146c..a77a2ae864e3 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -247,11 +247,11 @@ static inline const void *__tag_set(const void *addr, u8 tag) /* - * The linear kernel range starts at the bottom of the virtual address - * space. Testing the top bit for the start of the region is a - * sufficient check and avoids having to worry about the tag. + * Check whether an arbitrary address is within the linear map, which + * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the + * kernel's TTBR1 address range. */ -#define __is_lm_address(addr) (!(((u64)addr) & BIT(vabits_actual - 1))) +#define __is_lm_address(addr) (((u64)(addr) ^ PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET)) #define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET) #define __kimg_to_phys(addr) ((addr) - kimage_voffset)