From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793821465; b=GXdAIiUXx/sWWY/4vaee2izbRzjnlLKR2sWVNvBMjOVs+HI8xjaxfldozzTMLOy1GqQt FfA6PvYrs7kokLDHyqTv2wqvKTZNYmyUG6kKxUwNmBt6a/5ozLpGrTQwz/3rG6/DLRHx6 xWjng8Y63N1xILgsTkmnJW0qphNu+dg9JwrlAVRtZ7xgmmGSJLrZvbyFrxA8dVbrA1TqK Kn+V9G51bGeK/ryEZQV+O4yjSd0eMOEyDjSYQ1hmLq6hha9EExp7a/7hHUEJKPlLvgiva jQUvJZNurA5FBhlBeFW9lKL/fdZLWD8wSqiXScpT5FDjZAZI/Nia8zPsu9r9Idk/KYw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793821465; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID: In-Reply-To:References:MIME-Version:Content-Type:X-Mailer: X-Developer-Signature:X-Developer-Key:Content-Transfer-Encoding; bh=RGxB3CLuL3hdMOFW6c8rETuQc0/Gu93ks+OA3zHK0Kk=; b=oVlUJnpGXFJn9MtQrKPi9eWnkJniSYMXRaTXWr9KC8X/qH+oMUmi3qtnElybNfqRM2D1 V/OD/klsVoYjgQkpKPUBFLyG9XZrQS406L5LRzi+IlfSTcxeIBBNv9NcFjxgZWIsPXTUq Sej5g3nX7q3QT35BGfybyLscOGVGJsxqyyq77xzsYi09F0W/Sm6J9v/jXkSYw3DCIfxxJ eohQGmASHQ880DUMyQyBB55JKmFqoEXXd/WgLtazQyXj8V7CTsURIvUDBPBvVdve+GJVc b8mYdiKvvTdakzx8JxiBCmAcO0XBD1u6etfmEhsS1jmWcuR5gRTpnUrKKozXBssYE3A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HynF0hwX; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 13F676073817; Wed, 4 Nov 2026 19:44:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=HynF0hwX Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9144A1F00919; Wed, 4 Nov 2026 19:44:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793821464; bh=RGxB3CLuL3hdMOFW6c8rETuQc0/Gu93ks+OA3zHK0Kk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HynF0hwXz2ytbvRQ/tRwwiFgyWz0vIkPCQxUNQGSX/NnDGQ1w68NuKQ3Kbl+MqoQX 8J7oHXHcLTQG2lwNLxQCXX70LF0ZV8X7+sNuxCRB/h6LupRGDVaGgTpLhVB66N3rc6 tI4jBI+gZnk53Jn6xXJOB3T4pShCBRo0303YUYjU36zpeR5Fq1VBCTSBJgs9D7xNoL nRM7Nf0ZRQUe280MUMB6gTrfEPRIGT2ideQc9QRKVPxb3VQzoUYiRRvvW4mXYoSbZK CT7o3OoXqIatD6R9YkyrZxRNz94QoWOLCKEAfJ5VkH6HUvCBuSP/1PTuWytCnUt3iX I33mD4o8jVx+w== From: Christian Brauner To: linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jann Horn , Josef Bacik , Chris Mason , Jeff Layton , NeilBrown , Eric Dumazet , Thomas Gleixner , Al Viro , Jonathan Corbet , Christoph Hellwig , Greg Kroah-Hartman , Joel Granados , Kees Cook , Jan Kara , Jan Kara , linux-kernel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-acpi@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-um@lists.infradead.org, linux-wireless@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, platform-driver-x86@vger.kernel.org, coreteam@netfilter.org, kexec@lists.infradead.org, linux-pci@vger.kernel.org, linux-sound@vger.kernel.org, netfilter-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, ibm-acpi-devel@lists.sourceforge.net, jfs-discussion@lists.sourceforge.net, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-cifs@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mm@kvack.org, linux-sh@vger.kernel.org, linux-usb@vger.kernel.org, samba-technical@lists.samba.org, sparclinux@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-doc@vger.kernel.org, linux-serial@vger.kernel.org, linux-atm-general@lists.sourceforge.net, Takashi Iwai , linux-input@vger.kernel.org, linux-raid@vger.kernel.org, linux-ext4@vger.kernel.org, linux-modules@vger.kernel.org, linux-debuggers@vger.kernel.org, "Christian Brauner (Amutable)" , Chuck Lever Subject: [PATCH RESEND v2 08/26] s390/dasd: let procfs copy in writes to /proc/dasd/statistics Date: Wed, 4 Nov 2026 20:44:10 +0100 Message-ID: <20261104-work-procfs-drivers-v2-8-245e54e87116@kernel.org> In-Reply-To: <20261104-work-procfs-drivers-v2-0-245e54e87116@kernel.org> References: <20261104-work-procfs-drivers-v2-0-245e54e87116@kernel.org> X-Mailing-List: linux-debuggers@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=2121; i=brauner@kernel.org; h=from:subject:message-id; bh=tPoM7KW2jugAI3HBgjDAkvMMKrMKVevq5gq8BMZsIqc=; b=owGbwMvMwCU28Zj0gdSKO4sYT6slMWS97qqZsvLFCqNf+6XMazRbVi3d/ODSoR215t5nK5i4r bYImJcc6yhlYRDjYpAVU2RxaDcJl1vOU7HZKFMDZg4rE8gQBi5OAZjI84cM/wy2X+zn+HlNtd83 kD+IaZPCPqU9hps4WOckbNvx/OehSHlGhlOcc5yPTdmUf3fCaiuLkJ2aUg1lKVZe31ctszCW1p/ gyQMA X-Developer-Key: i=brauner@kernel.org; a=openpgp; fpr=4880B8C9BD0E5106FC070F4F7B3C391EFEA93624 Content-Transfer-Encoding: 8bit Implement ->proc_write_buf() so procfs copies in what is written before it pins the entry, and parse the command from that copy. Commands longer than PAGE_SIZE - 1 bytes are rejected now instead of cut at 64k. Signed-off-by: Christian Brauner (Amutable) --- drivers/s390/block/dasd_proc.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c index 86399427f01d..6c3bbb7dfe85 100644 --- a/drivers/s390/block/dasd_proc.c +++ b/drivers/s390/block/dasd_proc.c @@ -15,7 +15,6 @@ #include #include #include -#include #include #include @@ -247,17 +246,15 @@ static int dasd_stats_proc_show(struct seq_file *m, void *v) } static ssize_t dasd_stats_proc_write(struct file *file, - const char __user *user_buf, size_t user_len, loff_t *pos) + char *buffer, size_t user_len, loff_t *pos) { #ifdef CONFIG_DASD_PROFILE - char *buffer, *str; + char *str; int rc; - if (user_len > 65536) - user_len = 65536; - buffer = dasd_get_user_string(user_buf, user_len); - if (IS_ERR(buffer)) - return PTR_ERR(buffer); + /* strip linefeed */ + if (user_len && buffer[user_len - 1] == '\n') + buffer[user_len - 1] = 0; /* check for valid verbs */ str = skip_spaces(buffer); @@ -296,13 +293,11 @@ static ssize_t dasd_stats_proc_write(struct file *file, pr_info("The statistics have been reset\n"); } else goto out_parse_error; - vfree(buffer); return user_len; out_parse_error: rc = -EINVAL; pr_warn("%s is not a supported value for /proc/dasd/statistics\n", str); out_error: - vfree(buffer); return rc; #else pr_warn("/proc/dasd/statistics: is not activated in this kernel\n"); @@ -312,7 +307,7 @@ out_error: static const struct proc_ops dasd_stats_proc_ops = { .proc_show = dasd_stats_proc_show, - .proc_write = dasd_stats_proc_write, + .proc_write_buf = dasd_stats_proc_write, }; /* -- 2.53.0