From nobody Fri Oct 3 07:39:29 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47886227EB9; Thu, 4 Sep 2025 03:46:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756957617; cv=none; b=PD1ire6OUkQezpSYIc/ag91j4MsEuy7hiGHmyOLm6LOVmhKh5Q4whjJlrNT1OrCNCl9tBkhLWMGkjhL6qrDuJhCU3I5ABi0PW3VUjmX+uGshdFQKThQzTdAI4JsWBm4vPOj0A/EZ+Bd0toBM4xcZ6Wq6osNPiKhecOSW1YGb1E4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756957617; c=relaxed/simple; bh=fZM4pUskzgVzzDbqpdGr74pYeEbdYleorCSgkPRkjPo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=RXk6v+GNNZyzjceynnS2zqJNfCGRhKZSWRWZYW1SfCCEv3CgULRbt8CtwvaUdpfLPzIw4VFlEfqIxqRDda9vtGx2HPW+PzyshQM1zC2XysY82BFn0G8dSIJc6N+A0h0uBvY6J1UW8mNKl2Q+7twrdPUO8Cnd3qczvtL21cwNFFs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MlnAoabs; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MlnAoabs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F35AC4CEF8; Thu, 4 Sep 2025 03:46:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756957616; bh=fZM4pUskzgVzzDbqpdGr74pYeEbdYleorCSgkPRkjPo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MlnAoabsXDFgD+6GMVKhYGy490ebRIpVqlFFJafvlL4ISa9St9CrbCfmn4ifzaKP8 bX9ZGnDeiMZ9WVD74hcOBdalYxSesR/Y9E9Xp3fZUVaPSxEkYly/tS8sPOMzpqyamg 7ZHv5Lp3GL2zmaMDwclI3/cNq7KoLXqTKIynvUJeGCKg90SxQUiTnmFB39Hin5/IT3 zQnghkY80irwD/oWDUCf5PD59IuxNJmHwRDfk7+Ntr/3jMiSf0Y1EZQyhZ9V+rTbe8 IOFKkMm4JzBrzgo8BT4ZoAPLtu54jkDTYU9ucIiuUIpe+BFusthdcwzaJnimNmfjhR fdeZ2DNVeIaVQ== From: Kees Cook To: Peter Zijlstra Cc: Kees Cook , Nathan Chancellor , Vegard Nossum , Miguel Ojeda , Linus Walleij , Jeff Johnson , Randy Dunlap , David Woodhouse , "Russell King (Oracle)" , Nick Desaulniers , Bill Wendling , Justin Stitt , Marco Elver , Przemek Kitszel , Ramon de C Valle , Jonathan Corbet , "Paul E. McKenney" , Nicolas Schier , Masahiro Yamada , Arnd Bergmann , Krzysztof Kozlowski , Sami Tolvanen , Mark Rutland , linux-kernel@vger.kernel.org, llvm@lists.linux.dev, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 4/9] x86/cfi: Standardize on common "CFI:" prefix for CFI reports Date: Wed, 3 Sep 2025 20:46:43 -0700 Message-Id: <20250904034656.3670313-4-kees@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250904033217.it.414-kees@kernel.org> References: <20250904033217.it.414-kees@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2513; i=kees@kernel.org; h=from:subject; bh=fZM4pUskzgVzzDbqpdGr74pYeEbdYleorCSgkPRkjPo=; b=owGbwMvMwCVmps19z/KJym7G02pJDBk7OYsz1+h4pN6YrHiFfYKc4nMzjk9TFqvsF3i0eLNp4 e85Dt13O0pZGMS4GGTFFFmC7NzjXDzetoe7z1WEmcPKBDKEgYtTACZi2Mjwm71UTUCCm2ldnMdv n4CjPns8o37m5s18lb9NMcX97cNHfQz/lC+c1Jm4xNF6WfbPZ38mljIdef+n5p3DY2Nr7cz783f e4AUA X-Developer-Key: i=kees@kernel.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Use a regular "CFI:" prefix for CFI reports during alternatives setup, including reporting when nothing has happened (i.e. CONFIG_FINEIBT=3Dn). Signed-off-by: Kees Cook Reviewed-by: Nathan Chancellor --- Cc: Peter Zijlstra --- arch/x86/kernel/alternative.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 7bde68247b5f..d8f4ac95b4df 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1266,26 +1266,26 @@ static __init int cfi_parse_cmdline(char *str) } else if (!strcmp(str, "norand")) { cfi_rand =3D false; } else if (!strcmp(str, "warn")) { - pr_alert("CFI mismatch non-fatal!\n"); + pr_alert("CFI: mismatch non-fatal!\n"); cfi_warn =3D true; } else if (!strcmp(str, "paranoid")) { if (cfi_mode =3D=3D CFI_FINEIBT) { cfi_paranoid =3D true; } else { - pr_err("Ignoring paranoid; depends on fineibt.\n"); + pr_err("CFI: ignoring paranoid; depends on fineibt.\n"); } } else if (!strcmp(str, "bhi")) { #ifdef CONFIG_FINEIBT_BHI if (cfi_mode =3D=3D CFI_FINEIBT) { cfi_bhi =3D true; } else { - pr_err("Ignoring bhi; depends on fineibt.\n"); + pr_err("CFI: ignoring bhi; depends on fineibt.\n"); } #else - pr_err("Ignoring bhi; depends on FINEIBT_BHI=3Dy.\n"); + pr_err("CFI: ignoring bhi; depends on FINEIBT_BHI=3Dy.\n"); #endif } else { - pr_err("Ignoring unknown cfi option (%s).", str); + pr_err("CFI: Ignoring unknown option (%s).", str); } =20 str =3D next; @@ -1757,7 +1757,7 @@ static void __apply_fineibt(s32 *start_retpoline, s32= *end_retpoline, switch (cfi_mode) { case CFI_OFF: if (builtin) - pr_info("Disabling CFI\n"); + pr_info("CFI: disabled\n"); return; =20 case CFI_KCFI: @@ -1766,7 +1766,8 @@ static void __apply_fineibt(s32 *start_retpoline, s32= *end_retpoline, goto err; =20 if (builtin) - pr_info("Using kCFI\n"); + pr_info("CFI: Using %sretpoline kCFI\n", + cfi_rand ? "rehashed " : ""); return; =20 case CFI_FINEIBT: @@ -2005,6 +2006,8 @@ bool decode_fineibt_insn(struct pt_regs *regs, unsign= ed long *target, u32 *type) static void __apply_fineibt(s32 *start_retpoline, s32 *end_retpoline, s32 *start_cfi, s32 *end_cfi, bool builtin) { + if (IS_ENABLED(CONFIG_CFI) && builtin) + pr_info("CFI: Using standard kCFI\n"); } =20 #ifdef CONFIG_X86_KERNEL_IBT --=20 2.34.1