From patchwork Thu Sep 19 12:45:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Berg X-Patchwork-Id: 1987365 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=z9mwbA3C; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=sipsolutions.net header.i=@sipsolutions.net header.a=rsa-sha256 header.s=mail header.b=LmANmG1b; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:3::133; helo=bombadil.infradead.org; envelope-from=linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=patchwork.ozlabs.org) Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4X8Zxn1G1Qz1y1g for ; Thu, 19 Sep 2024 22:45:49 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dKpH+tlU423xOURAFjrKZyJAMssXrMwBVe1nv9ITqEw=; b=z9mwbA3CD2OoG6h76FxTmZkDTG SGrBP/4+Fqot7wvPPbqHWEP8UZB2oBa4cRc25DI3CM6zm5wwAFu1MgzE59LET9jlmJVRCNWm+wIbH n9WN9+JO+ZOl61MH8TCy9DW+R2xSkx/x0b2l3M89pHCRyNvO2ykgVSO6eELCtM1BWphqFFOjIb8cP dA3APlmDZ8WBn/76V5M5pQDV7elsAUYoKgMDmKokhraTXQgr44hlhs1CNOxdTtUxuMKvSio5wIgRX h2pCK0ZdA/Wc46ck5KB2I+JGKpSG0KUIYXpQo3hmv4GW8JZKxK17HsQvehCw8EWNSG7lenuogZUq8 NXHb8ENA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1srGXb-0000000AGro-1fFL; Thu, 19 Sep 2024 12:45:47 +0000 Received: from s3.sipsolutions.net ([2a01:4f8:242:246e::2] helo=sipsolutions.net) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1srGXY-0000000AGq7-0rjQ for linux-um@lists.infradead.org; Thu, 19 Sep 2024 12:45:45 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Content-Type:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=dKpH+tlU423xOURAFjrKZyJAMssXrMwBVe1nv9ITqEw=; t=1726749944; x=1727959544; b=LmANmG1bZs1ZwCnVCQuo3y5KrJLeEslA+GuoN/F4IpKzWPE /D/jqLALo6kYqzP2evyYQ9hxeghCqsZuYwC74JVwzM439L+nxLnOPDNFTx1uhvAVJNNwwk+4KQIW3 MqZr+zhdfCRGhdRAfBPz3tmBHve56n7Tt6hmhIhedDGzoUbXYIfaGaN9lCMZsQJO8tNe91nnvUFS4 //hXKU8manvk3OUiEKhDmv7VOwsDiyqUpSvxou535isOCJCAj6qnqXBdmtGJtEiT3i6hOLb48MUwo 5QFFOP+VPsNdz3ipsCByLO78oN943xUZfZAB+zAgw4zRvrf+OHI35W8gsgR+1bLA==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.97) (envelope-from ) id 1srGXW-000000047AZ-0G6r; Thu, 19 Sep 2024 14:45:42 +0200 From: Benjamin Berg To: linux-um@lists.infradead.org Cc: Benjamin Berg Subject: [PATCH v9 05/10] um: Add compile time assert that stub fits on a page Date: Thu, 19 Sep 2024 14:45:06 +0200 Message-ID: <20240919124511.282088-6-benjamin@sipsolutions.net> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240919124511.282088-1-benjamin@sipsolutions.net> References: <20240919124511.282088-1-benjamin@sipsolutions.net> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240919_054544_328815_7BC61EAD X-CRM114-Status: UNSURE ( 8.63 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -2.1 (--) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: From: Benjamin Berg The code assumes that the stub code can fit into a single page. This is unlikely to ever change, but add a link time assert instead so that there will be no hard to debug error. Content analysis details: (-2.1 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org From: Benjamin Berg The code assumes that the stub code can fit into a single page. This is unlikely to ever change, but add a link time assert instead so that there will be no hard to debug error. Signed-off-by: Benjamin Berg --- arch/um/kernel/dyn.lds.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/um/kernel/dyn.lds.S b/arch/um/kernel/dyn.lds.S index 3385d653ebd0..dc9d9a68af55 100644 --- a/arch/um/kernel/dyn.lds.S +++ b/arch/um/kernel/dyn.lds.S @@ -178,3 +178,6 @@ SECTIONS DISCARDS } + +ASSERT(__syscall_stub_end - __syscall_stub_start <= PAGE_SIZE, + "STUB code must not be larger than one page");