From nobody Thu Nov 28 00:32:43 2024 Received: from mail-oa1-f48.google.com (mail-oa1-f48.google.com [209.85.160.48]) (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 48716800; Mon, 7 Oct 2024 06:53:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.48 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728283995; cv=none; b=s8pbnF0n5J9Gux8oyGk3LrykmNY5usqlSW+0tk+CP404yzvKsDoVbnXnATF//eVoJYetHGgPSEt/0h/uMmj0MhgFmJurtYM6LJVt39zy7wTwxV1S7zkRbuftr/qZyNVM9WvlHlfJvVo6qXennSTjz+2Zygdk4oWz0w6T0Ia8A8Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728283995; c=relaxed/simple; bh=MhoIs3jpZky22qoMXlfwHS5b1TYGEYKhWGXzdqB4OTE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Prj4QoqzOnUSBaIsj6Sx+NS4UCeOle/5hZwnsU2auMZ4poP5YoNAxIPlEy4r9oTDhW0bXUo1Ptj16KAd10FUqxcurCfUbbFlCGPiCwbnmHs5AEgdCJcMD0uqZm8IRYcmI1mqlzqgX3aR5tuGBcRur4lAZZs4WPfLh/n7zYADHZo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=PxRzDPye; arc=none smtp.client-ip=209.85.160.48 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PxRzDPye" Received: by mail-oa1-f48.google.com with SMTP id 586e51a60fabf-287df15714cso676494fac.2; Sun, 06 Oct 2024 23:53:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1728283993; x=1728888793; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=ceeahQe9wcl46lPcO7fUS/hyZJL8m6PhkmRtZJytXcI=; b=PxRzDPyeDu/hzK/fqr3bsUz+H99wpkJs71bhs0+cfVWqekWFrV18NONWC8x8lD3hFf QW6qwrzgwYB6wlMfdUyN/w8SD2ndjQ5swClZlOGLpmL4VkrS068rUhCQCCmd3D1tVc8H p3yFd2kDh+OLMu8AxQaDAz6gcNsjW0wzlVLY7itZJuNQp2k0hNedG2k3PFjEnL1GTZf7 PPcgL5j25gZVNjQTx+uivcjnhdro5V9Wz+VCYiL20VvD2j0kb9SznYOc1OldKNBWu3xy uHw9nt1v1KpWygsJUaDDdY7FIKl4QPiNfiBqu9R4OBiOpot50C0tv4ZGB5j9da5nH9q2 /XYA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728283993; x=1728888793; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=ceeahQe9wcl46lPcO7fUS/hyZJL8m6PhkmRtZJytXcI=; b=e1+lkI+9GlGg9JpY8I2cQX0lZnjfWxgK7Z3pwvfXT8GYEEoHv0lPTslRw5/fxury6e Ht97XgPsZbzVG1jDn7W/Md+DNr5TNTSz8Vdbq5V7csOmfHMce3kvYfcVoVzSp19bre7t DW1SMeDKLaNA13qKKmgI1UxBqOZhkOMIrPHO4E5ziThkUSEePBQD9JQBPEeE89YR9KkP SPLBYkRkzp212iBr0XhMjIagrTOxzyhE8vXuG2rem45+IAGmTO6RY4zfMsMWJYa8wgM/ XKofL/cb/kgsjo6xY8Cop5NvD7+4pswOMiFOWtt5GIp1MiUOBsluKit8xWYNITbR1T65 MhtA== X-Forwarded-Encrypted: i=1; AJvYcCV2zpZfE6Vni54kdlAYv+K+nzLHqGOifc2GgFzOysQUOakr/75NWAYPaIFu2doc2p1hR9r5slnhWJd8hdA=@vger.kernel.org, AJvYcCXnpLt1YIRvbpCeBsnLbpZowWc3OSt85rQXyjp4Q7KcWR72VL2hovm8HTs1xzBmycizRYV8CsrA@vger.kernel.org X-Gm-Message-State: AOJu0YysxZjAaM7lXefGM1LfAa5Ui5/gd+pfcSRHlITPSaicN9zXdpHO +QxnMDXE9opOVkPmihU4xcrmK7powPjQQQCiiBwBe5p7wSul4eEn X-Google-Smtp-Source: AGHT+IEpvg/fv2oPovXfNcR+vR0vuvo5MLzuioMarvk5onqXjaJ/QULoZRprNjdBZBm6qHzZvky/qg== X-Received: by 2002:a05:6870:168a:b0:287:7695:6a87 with SMTP id 586e51a60fabf-287c1d38d48mr6445913fac.10.1728283993195; Sun, 06 Oct 2024 23:53:13 -0700 (PDT) Received: from kernelexploit-virtual-machine.localdomain ([121.185.186.233]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-7e9f6c376cfsm3542555a12.61.2024.10.06.23.53.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 06 Oct 2024 23:53:12 -0700 (PDT) From: Jeongjun Park To: akpm@linux-foundation.org Cc: usama.anjum@collabora.com, peterx@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Jeongjun Park Subject: [PATCH] mm: remove the newlines, which are added for unknown reasons and interfere with bug analysis Date: Mon, 7 Oct 2024 15:53:07 +0900 Message-Id: <20241007065307.4158-1-aha310510@gmail.com> X-Mailer: git-send-email 2.34.1 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" Looking at the source code links for mm/memory.c in the sample reports=20 in the syzbot report links [1]. it looks like the line numbers are designated as lines that have been=20 increased by 1. This may seem like a problem with syzkaller or the=20 addr2line program that assigns the line numbers, but there is no problem=20 with either of them. In the previous commit d61ea1cb0095 ("userfaultfd: UFFD_FEATURE_WP_ASYNC"),=20 when modifying mm/memory.c, an unknown line break is added to the very firs= t=20 line of the file. However, the git.kernel.org site displays the source code=20 with the added line break removed, so even though addr2line has assigned=20 the correct line number, it looks like the line number has increased by 1. This may seem like a trivial thing, but I think it would be appropriate=20 to remove all the newline characters added to the upstream and stable=20 versions, as they are not only incorrect in terms of code style but also=20 hinder bug analysis. [1] https://syzkaller.appspot.com/bug?extid=3D4145b11cdf925264bff4 https://syzkaller.appspot.com/bug?extid=3Dfa43f1b63e3aa6f66329 https://syzkaller.appspot.com/bug?extid=3D890a1df7294175947697 Fixes: d61ea1cb0095 ("userfaultfd: UFFD_FEATURE_WP_ASYNC") Cc: stable@vger.kernel.org Signed-off-by: Jeongjun Park Reported-by: Jeongjun Park --- mm/memory.c | 1 - 1 file changed, 1 deletion(-) diff --git a/mm/memory.c b/mm/memory.c index 2366578015ad..7dffe8749014 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1,4 +1,3 @@ - // SPDX-License-Identifier: GPL-2.0-only /* * linux/mm/memory.c --