From patchwork Mon Feb 21 08:48:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 544893 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 7244FC433F5 for ; Mon, 21 Feb 2022 09:14:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348196AbiBUJO0 (ORCPT ); Mon, 21 Feb 2022 04:14:26 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:34782 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348365AbiBUJLQ (ORCPT ); Mon, 21 Feb 2022 04:11:16 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E0C823BDC; Mon, 21 Feb 2022 01:03:13 -0800 (PST) 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 sin.source.kernel.org (Postfix) with ESMTPS id 608BACE0E79; Mon, 21 Feb 2022 09:03:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49614C340E9; Mon, 21 Feb 2022 09:03:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1645434190; bh=gBR3Ce/pJ47IRQg4FP9Z/vuY4SpFZJm7Vp0omlNnSeg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=njrCeZjdHsg2VcyShX0hQTHPPpW1WJ3Bom7GIwN7laGJUEtJ5W7/1wpi2aV958qfK 6eZhkE9KYyLUFUcS63xppJ7TJL0VgGSneIrypCgTwpop1JDC2FAUUvjMBw7EKA5Ta8 6gr/WijwAHPP/RXS5TlLb4/rzMMFwdCpLH5F8xjI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Popov , Peter Zijlstra , Kees Cook , Linus Torvalds , Sasha Levin Subject: [PATCH 5.10 043/121] gcc-plugins/stackleak: Use noinstr in favor of notrace Date: Mon, 21 Feb 2022 09:48:55 +0100 Message-Id: <20220221084922.671268396@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220221084921.147454846@linuxfoundation.org> References: <20220221084921.147454846@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kees Cook [ Upstream commit dcb85f85fa6f142aae1fe86f399d4503d49f2b60 ] While the stackleak plugin was already using notrace, objtool is now a bit more picky. Update the notrace uses to noinstr. Silences the following objtool warnings when building with: CONFIG_DEBUG_ENTRY=y CONFIG_STACK_VALIDATION=y CONFIG_VMLINUX_VALIDATION=y CONFIG_GCC_PLUGIN_STACKLEAK=y vmlinux.o: warning: objtool: do_syscall_64()+0x9: call to stackleak_track_stack() leaves .noinstr.text section vmlinux.o: warning: objtool: do_int80_syscall_32()+0x9: call to stackleak_track_stack() leaves .noinstr.text section vmlinux.o: warning: objtool: exc_general_protection()+0x22: call to stackleak_track_stack() leaves .noinstr.text section vmlinux.o: warning: objtool: fixup_bad_iret()+0x20: call to stackleak_track_stack() leaves .noinstr.text section vmlinux.o: warning: objtool: do_machine_check()+0x27: call to stackleak_track_stack() leaves .noinstr.text section vmlinux.o: warning: objtool: .text+0x5346e: call to stackleak_erase() leaves .noinstr.text section vmlinux.o: warning: objtool: .entry.text+0x143: call to stackleak_erase() leaves .noinstr.text section vmlinux.o: warning: objtool: .entry.text+0x10eb: call to stackleak_erase() leaves .noinstr.text section vmlinux.o: warning: objtool: .entry.text+0x17f9: call to stackleak_erase() leaves .noinstr.text section Note that the plugin's addition of calls to stackleak_track_stack() from noinstr functions is expected to be safe, as it isn't runtime instrumentation and is self-contained. Cc: Alexander Popov Suggested-by: Peter Zijlstra Signed-off-by: Kees Cook Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- kernel/stackleak.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/kernel/stackleak.c b/kernel/stackleak.c index ce161a8e8d975..dd07239ddff9f 100644 --- a/kernel/stackleak.c +++ b/kernel/stackleak.c @@ -48,7 +48,7 @@ int stack_erasing_sysctl(struct ctl_table *table, int write, #define skip_erasing() false #endif /* CONFIG_STACKLEAK_RUNTIME_DISABLE */ -asmlinkage void notrace stackleak_erase(void) +asmlinkage void noinstr stackleak_erase(void) { /* It would be nice not to have 'kstack_ptr' and 'boundary' on stack */ unsigned long kstack_ptr = current->lowest_stack; @@ -102,9 +102,8 @@ asmlinkage void notrace stackleak_erase(void) /* Reset the 'lowest_stack' value for the next syscall */ current->lowest_stack = current_top_of_stack() - THREAD_SIZE/64; } -NOKPROBE_SYMBOL(stackleak_erase); -void __used __no_caller_saved_registers notrace stackleak_track_stack(void) +void __used __no_caller_saved_registers noinstr stackleak_track_stack(void) { unsigned long sp = current_stack_pointer;