From nobody Mon Feb 9 23:39:00 2026 Received: from mail-pl1-f176.google.com (mail-pl1-f176.google.com [209.85.214.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 56F96143748 for ; Wed, 14 Aug 2024 08:56:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.176 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723625788; cv=none; b=rCe++F5SPlZQMFc6k9+lKfwmK+JEeJAdEbAYyRGlI89SZb/wjsny7i6LbxQP2wu3I1cYtExGGFGzdrEZId7271pjNXVb8uLzfRFhomtZBJRD8Q/VaFv5iCGsDSfDcJCYHCzfgJoYpqwldDa5FxdjEbiPzludXFO6ir+baFgqZwU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723625788; c=relaxed/simple; bh=y57VQrw88WGtL67OnREsNbCLIoyGKBbMu8jjNLherto=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kRlE0CKgB4kfy9QjqMXjCqpUvotWpCdRXz/UhaE8MQ2Xcd9/H9NRrCNUqs8AM8LkLIMxSMvOQUva2IniSe2H89exgEcO2lKqhGaxO83EnJE3jR6HS6TjF0CyORhw6A3wGOBngRbicKLIAFYd7f8shlZ5vMb6OhE+sW0b4vcy/X8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=sifive.com; spf=pass smtp.mailfrom=sifive.com; dkim=pass (2048-bit key) header.d=sifive.com header.i=@sifive.com header.b=fa0oDjbZ; arc=none smtp.client-ip=209.85.214.176 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=sifive.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sifive.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sifive.com header.i=@sifive.com header.b="fa0oDjbZ" Received: by mail-pl1-f176.google.com with SMTP id d9443c01a7336-201d9fa899dso3340105ad.3 for ; Wed, 14 Aug 2024 01:56:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; t=1723625786; x=1724230586; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Kr1OlloTvp35mKilBnuEZzypgigPXmCly4KSd56Q7OI=; b=fa0oDjbZbgr4xd6nKBksU4Kp2m+kLGIXIg/TvfAb1aztZF7/S0NqYHEszu1Bdbhwr5 4/k6VV8pHqXNNgE/5uqwOuKm9RYb0KXT50zpfsYqnBOjvKrQNkzPpduhOGSXy0DCap1l 3KktgQZq61SVGLatNr+QQC/ERYNDuK3vvOzD6NVaXYUzrtzrDjWDnRJcCaNHGe6BkJCx fRRJgjSyVVqym7BMfHOpBB3TP0VujuFgvbMxghUDdgpWIEg5pOEe3xrxAvVUk2WJPQ7Y ICAK4vWbMVVfZGRSCb1D2wVA5TRlY75iE8gZwleMh6+bWw8QY8QiRieFmgmBbdNkhXoM p47A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723625786; x=1724230586; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Kr1OlloTvp35mKilBnuEZzypgigPXmCly4KSd56Q7OI=; b=Qf3OnPKRS9sDD9nB8A17ow6Q7CAntAv6JCsoUenZLOlO9H71vI6UpKPLoeBSiEIZoN G5V6spSCpvXad8CpJMQ9/SExeg2nlhUnCWHGGkOGrwE8yeJkP6LLJVP+9wUItpFzDu3l pIxQ2lxhe1/s6ejwK6Uwgf+04zrKwxX3VLbVpxG2U10oa8k587igNIltroAcM3ONZluD DpQBOmj1a5EPGd4k+3CGkIqGHpWft24FyGDfu1bdoBj3srnFo1SsbODVIqF/naUoDkOh u3FkjYA6ap72ekn098ZBsE9aGyT8kBfbHc+M0d+N89slNO/Zv/eKNIgTDzaPCGuUx7zn /Pzg== X-Forwarded-Encrypted: i=1; AJvYcCW6UtBWMvtffxEVWKqchEjZMvuwdHnvwttEqVXG3THpxfZC69lWOYf0Q2YGWRXXi4BLEzPPB1BqfoSiJE5eREr5yeZeGP5/wt27QTCy X-Gm-Message-State: AOJu0YyI0hnNMDFdUyVNfiONttK9DYJoB7IteJjdV7RaSSM18mXcoAN0 92NCkc4xkeiCLCOTLkhHBdNUfd5kmeUCXt3sHLXuFob84N6mD4M6TlFoZOzb0/E= X-Google-Smtp-Source: AGHT+IE20LewatO25ueMR3XW0aRNE3Ho00UvK46l5CUL7vUBX+0A3K1zUsQysbjVk0qPCHhMgq/ydQ== X-Received: by 2002:a17:903:360d:b0:1ff:49a0:46b1 with SMTP id d9443c01a7336-201d6397db6mr25518915ad.6.1723625785721; Wed, 14 Aug 2024 01:56:25 -0700 (PDT) Received: from sw06.internal.sifive.com ([4.53.31.132]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-201cd14a7b8sm25439615ad.100.2024.08.14.01.56.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Aug 2024 01:56:25 -0700 (PDT) From: Samuel Holland To: Palmer Dabbelt , linux-riscv@lists.infradead.org, Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , kasan-dev@googlegroups.com Cc: llvm@lists.linux.dev, linux-kernel@vger.kernel.org, Alexandre Ghiti , Evgenii Stepanov , Andrew Morton , linux-arm-kernel@lists.infradead.org, Samuel Holland Subject: [RFC PATCH 3/7] kasan: sw_tags: Support tag widths less than 8 bits Date: Wed, 14 Aug 2024 01:55:31 -0700 Message-ID: <20240814085618.968833-4-samuel.holland@sifive.com> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240814085618.968833-1-samuel.holland@sifive.com> References: <20240814085618.968833-1-samuel.holland@sifive.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Allow architectures to override KASAN_TAG_KERNEL in asm/kasan.h. This is needed on RISC-V, which supports 57-bit virtual addresses and 7-bit pointer tags. For consistency, move the arm64 MTE definition of KASAN_TAG_MIN to asm/kasan.h, since it is also architecture-dependent; RISC-V's equivalent extension is expected to support 7-bit hardware memory tags. Signed-off-by: Samuel Holland Reviewed-by: Andrey Konovalov --- arch/arm64/include/asm/kasan.h | 6 ++++-- arch/arm64/include/asm/uaccess.h | 1 + include/linux/kasan-tags.h | 13 ++++++++----- 3 files changed, 13 insertions(+), 7 deletions(-) diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h index e1b57c13f8a4..4ab419df8b93 100644 --- a/arch/arm64/include/asm/kasan.h +++ b/arch/arm64/include/asm/kasan.h @@ -6,8 +6,10 @@ =20 #include #include -#include -#include + +#ifdef CONFIG_KASAN_HW_TAGS +#define KASAN_TAG_MIN 0xF0 /* minimum value for random tags */ +#endif =20 #define arch_kasan_set_tag(addr, tag) __tag_set(addr, tag) #define arch_kasan_reset_tag(addr) __tag_reset(addr) diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uacc= ess.h index 28f665e0975a..56a09f412272 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include diff --git a/include/linux/kasan-tags.h b/include/linux/kasan-tags.h index 4f85f562512c..e07c896f95d3 100644 --- a/include/linux/kasan-tags.h +++ b/include/linux/kasan-tags.h @@ -2,13 +2,16 @@ #ifndef _LINUX_KASAN_TAGS_H #define _LINUX_KASAN_TAGS_H =20 +#include + +#ifndef KASAN_TAG_KERNEL #define KASAN_TAG_KERNEL 0xFF /* native kernel pointers tag */ -#define KASAN_TAG_INVALID 0xFE /* inaccessible memory tag */ -#define KASAN_TAG_MAX 0xFD /* maximum value for random tags */ +#endif + +#define KASAN_TAG_INVALID (KASAN_TAG_KERNEL - 1) /* inaccessible memory ta= g */ +#define KASAN_TAG_MAX (KASAN_TAG_KERNEL - 2) /* maximum value for random = tags */ =20 -#ifdef CONFIG_KASAN_HW_TAGS -#define KASAN_TAG_MIN 0xF0 /* minimum value for random tags */ -#else +#ifndef KASAN_TAG_MIN #define KASAN_TAG_MIN 0x00 /* minimum value for random tags */ #endif =20 --=20 2.45.1