From nobody Mon Apr 6 12:33:15 2026 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 BB56BC38145 for ; Wed, 7 Sep 2022 10:06:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229734AbiIGKGO (ORCPT ); Wed, 7 Sep 2022 06:06:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46340 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229604AbiIGKFy (ORCPT ); Wed, 7 Sep 2022 06:05:54 -0400 Received: from smtp1.axis.com (smtp1.axis.com [195.60.68.17]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C21337B7B5 for ; Wed, 7 Sep 2022 03:05:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; q=dns/txt; s=axis-central1; t=1662545148; x=1694081148; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=oNTEly+VN1w0GXZfx3c8iIp7/UMbftmaEYgIr51BAs0=; b=HKPmsEYCpaUn9oI2GMpJqyrPIu0LtaTR1VDRnKRxSmBtm65V9H+XXfce T11BI5TrGd4m4TVZ/cXxNlTETWQomJFt81lkSmTVMvZPGQOvGWa1jfFBN 7sfe7KZ4ozOwApJx12gX+35Ll4qF5Da+JmsU294KrmyAsh4UA/uakOnlC cx2+30AlurjXjohjgoQruYkDP0ICRLFpbIRyGmaWR0o+xNf2vmwKlCVS9 MlifoTHDqIzHiUMkF7GhB0E/AYnxddy25WMg8RyAOoq2lS/xjn3q/7Z4q eTtBIao2OSXQvIpGPOQsqxxvvIRhX36LGRZa58FayKBAwl+Uio6TnqXBb g==; From: Vincent Whitchurch To: Richard Weinberger , Anton Ivanov , Johannes Berg CC: , Vincent Whitchurch , Patricia Alfonso , Dmitry Vyukov , Andrey Konovalov , , Subject: [PATCH] um: Prevent KASAN splats in dump_stack() Date: Wed, 7 Sep 2022 12:05:33 +0200 Message-ID: <20220907100533.1719128-1-vincent.whitchurch@axis.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Use READ_ONCE_NOCHECK() when reading the stack to prevent KASAN splats when dump_stack() is used. Fixes: 5b301409e8bc5d7fad ("UML: add support for KASAN under x86_64") Signed-off-by: Vincent Whitchurch Reviewed-by: Dmitry Vyukov --- arch/um/kernel/sysrq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/um/kernel/sysrq.c b/arch/um/kernel/sysrq.c index 7452f70d50d0..746715379f12 100644 --- a/arch/um/kernel/sysrq.c +++ b/arch/um/kernel/sysrq.c @@ -48,7 +48,8 @@ void show_stack(struct task_struct *task, unsigned long *= stack, break; if (i && ((i % STACKSLOTS_PER_LINE) =3D=3D 0)) pr_cont("\n"); - pr_cont(" %08lx", *stack++); + pr_cont(" %08lx", READ_ONCE_NOCHECK(*stack)); + stack++; } =20 printk("%sCall Trace:\n", loglvl); --=20 2.34.1