From mboxrd@z Thu Jan 1 00:00:00 1970 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 EA03E38FB9; Mon, 25 Aug 2025 14:26:03 +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=1756131964; cv=none; b=oswmYukC9XnZmjoo24LM1uZG9kOM2jVqyifPlz86iDPs5KeeOix31fiq+4+PLCCYDnRaSPAa67yU/KaWRr1/sc9GQnnNUBWjTKYQf2EchU89aMxq4/MqHzBuWmxcdxyNkDEvUsptPqzFU0wJQ/K/M/39m/WyxPuV45m7dVb4/No= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756131964; c=relaxed/simple; bh=qKnJwvVOQdbIM7AwmZDu1aieujqnr4MVL8xJV+3xcWU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=TEjIRi1LXKuBLD5jUTAohhszLUME9ODlaUxswkhzMvaE1nUsCmECAhCX/G/L2Lhxv9xRQ11w2hl4so/ZwxuUj0ixsS4d1otDpLwZ/5ocE7K6/rk/9y8teH+GtNB4u99nPSvEjBO3tp2ruN+GHO6rQm1kf0X7OvKkuQjrlBJLs/E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bPWPBLMJ; 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="bPWPBLMJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81222C116C6; Mon, 25 Aug 2025 14:26:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756131963; bh=qKnJwvVOQdbIM7AwmZDu1aieujqnr4MVL8xJV+3xcWU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bPWPBLMJbqPu4Ihz/jn1p85BL57qjQm0GeXE5FNWeLlN++/7RKlMCJ8dHmh3NN98j a2MJOEJMImQWuqo4ojpxl7wQxUW+kMSttdKngdXjPS2kCUyc+BZ+1e8oOgQ0Ti2/6m reEgKi6EjffV33DLzQyIgr8V9g2nlmSVYUG7EaM/MyY7M2lKY2Zv/dN2S7hOdASMCl /HccRg3BXD9cdYB8R3XGPA4vYe8uLuojG1CaSJ1AIvlscFmLwGNseHrwr/ONQGONLO cnGyoQE6fc06n1ued9gtzzjBPgY/6MjOfjPP43UQ+V4sPfnprtr50fs3xdqa5Qy6Yd aMsiVDBIbNsJA== From: Kees Cook To: Peter Zijlstra Cc: Kees Cook , Sami Tolvanen , David Woodhouse , Linus Walleij , Mark Rutland , Puranjay Mohan , Jonathan Corbet , Nathan Chancellor , x86@kernel.org, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, llvm@lists.linux.dev, linux-hardening@vger.kernel.org Subject: [PATCH 2/5] x86/traps: Clarify KCFI instruction layout Date: Mon, 25 Aug 2025 07:25:49 -0700 Message-Id: <20250825142603.1907143-2-kees@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250825141316.work.967-kees@kernel.org> References: <20250825141316.work.967-kees@kernel.org> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Just a nit-picky change to the KCFI indirect call check instruction documentation. The addl offset isn't always -4 (it depends on patchable function entry configuration). Signed-off-by: Kees Cook --- arch/x86/kernel/cfi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cfi.c b/arch/x86/kernel/cfi.c index 77086cf565ec..638eb5c933e0 100644 --- a/arch/x86/kernel/cfi.c +++ b/arch/x86/kernel/cfi.c @@ -27,7 +27,7 @@ static bool decode_cfi_insn(struct pt_regs *regs, unsigned long *target, * for indirect call checks: * *   movl -, %r10d ; 6 bytes - * addl -4(%reg), %r10d ; 4 bytes + * addl -(%reg), %r10d; 4 bytes * je .Ltmp1 ; 2 bytes * ud2 ; <- regs->ip * .Ltmp1: -- 2.34.1