From patchwork Tue Apr 21 13:57:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Emanuele Giuseppe Esposito X-Patchwork-Id: 11501501 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9F8851575 for ; Tue, 21 Apr 2020 13:58:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8491A2071C for ; Tue, 21 Apr 2020 13:58:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="apsS1Fm0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729035AbgDUN57 (ORCPT ); Tue, 21 Apr 2020 09:57:59 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:55272 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728963AbgDUN56 (ORCPT ); Tue, 21 Apr 2020 09:57:58 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1587477475; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xjaOnzI5gdueJ0y4sy2VdCpkInG/pM8xAJAe7M5MwVA=; b=apsS1Fm0qtV6O0VidnFF2wOKPSvn/99MeZShrhxZtnNwSBqdtCDBoJJrzYHvPiwagMghOQ LydCVkk+/L+zARF6pCT79i7HgGqQ/iDDpzQIJOF67ncrSVPORpaJ3U15p/IKw4I02yOQ4g Tdk2mjIwKXWDiJ6yIjvahFA3olN9xdc= Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-186-ynLx0rIJOg6l0x-Q1vNEZQ-1; Tue, 21 Apr 2020 09:57:53 -0400 X-MC-Unique: ynLx0rIJOg6l0x-Q1vNEZQ-1 Received: by mail-wr1-f71.google.com with SMTP id f2so7535963wrm.9 for ; Tue, 21 Apr 2020 06:57:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=xjaOnzI5gdueJ0y4sy2VdCpkInG/pM8xAJAe7M5MwVA=; b=Im0XwMELgWDmfzOQGpQhbAGfHu4C6BmqunkXHpQPfnb3GBNOUEyPhu2PWw/7eKEywG SXeJ0fboU8DPtmTSVBCuhoZvZqqX8z/TfgLpEp69U+vjK0fNqgHh56sd3NYqBM+hE8Fs Oc3d5GeZ33Z7lBCz0weGhufMvJeptGFYaqIhPbz/jp5w0ij+pzx4gPWOLyxi+J8Fwvq8 DxEQJDd83yRGFitUSxI8XKKgPaHa7nTJ8TE3DF76gDkxnY6rOf88J1x8v4NccNAqSgoF R8SwLtVPio3M1I/niHbdSROmZA0auxa9LeCgxO0pIbdyyWBxO6RcYA+jlJnpogaIwwqj Euhg== X-Gm-Message-State: AGi0PuZwZ+m7Xk6B2kEKisDt3rHY9R95Kpx4eBQsjcldXyMZU+qVfaZm B01aadyUFZ43/hYZITpx7mXsb/I+v5RXalJqgVpDAyT1ILOqHW8gkYQ6Lo9D3bu01ISecT9Upga /KpMOi9ciFNREIm4y1LvI5Y9wjkABt8Y860qA X-Received: by 2002:a1c:9c0a:: with SMTP id f10mr5022063wme.139.1587477472394; Tue, 21 Apr 2020 06:57:52 -0700 (PDT) X-Google-Smtp-Source: APiQypIlG2viM+l0EuPG6wic3zBlhrKU/He9H0puv0ur4Y4UIWdpPnCyTzA3FMh8mbZkb38/fp+4ZQ== X-Received: by 2002:a1c:9c0a:: with SMTP id f10mr5022031wme.139.1587477472153; Tue, 21 Apr 2020 06:57:52 -0700 (PDT) Received: from localhost.localdomain.com ([194.230.155.194]) by smtp.gmail.com with ESMTPSA id f23sm3562989wml.4.2020.04.21.06.57.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Apr 2020 06:57:51 -0700 (PDT) From: Emanuele Giuseppe Esposito To: linux-fsdevel@vger.kernel.org Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Frederic Barrat , Andrew Donnellan , Arnd Bergmann , Greg Kroah-Hartman , "Manoj N. Kumar" , "Matthew R. Ochs" , Uma Krishnan , "James E.J. Bottomley" , "Martin K. Petersen" , Alexander Viro , Joel Becker , Christoph Hellwig , "Rafael J. Wysocki" , John Johansen , James Morris , "Serge E. Hallyn" , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-scsi@vger.kernel.org, linux-security-module@vger.kernel.org, Paolo Bonzini , Emanuele Giuseppe Esposito Subject: [PATCH v2 6/7] debugfs: switch to simplefs inode creation API Date: Tue, 21 Apr 2020 15:57:40 +0200 Message-Id: <20200421135741.30657-4-eesposit@redhat.com> X-Mailer: git-send-email 2.25.2 In-Reply-To: <20200421135119.30007-1-eesposit@redhat.com> References: <20200421135119.30007-1-eesposit@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The only difference, compared to the pre-existing code, is that symlink creation now triggers fsnotify_create. This was a bug in the debugfs code, since for example vfs_symlink does call fsnotify_create. Signed-off-by: Emanuele Giuseppe Esposito --- fs/debugfs/inode.c | 144 +++++---------------------------------------- 1 file changed, 15 insertions(+), 129 deletions(-) diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index 5dbb74a23e7c..ccbeea9e5f6c 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -305,68 +305,6 @@ struct dentry *debugfs_lookup(const char *name, struct dentry *parent) } EXPORT_SYMBOL_GPL(debugfs_lookup); -static struct dentry *start_creating(const char *name, struct dentry *parent) -{ - struct dentry *dentry; - int error; - - pr_debug("creating file '%s'\n", name); - - if (IS_ERR(parent)) - return parent; - - error = simple_pin_fs(&debugfs, &debug_fs_type); - if (error) { - pr_err("Unable to pin filesystem for file '%s'\n", name); - return ERR_PTR(error); - } - - /* If the parent is not specified, we create it in the root. - * We need the root dentry to do this, which is in the super - * block. A pointer to that is in the struct vfsmount that we - * have around. - */ - if (!parent) - parent = debugfs.mount->mnt_root; - - inode_lock(d_inode(parent)); - if (unlikely(IS_DEADDIR(d_inode(parent)))) - dentry = ERR_PTR(-ENOENT); - else - dentry = lookup_one_len(name, parent, strlen(name)); - if (!IS_ERR(dentry) && d_really_is_positive(dentry)) { - if (d_is_dir(dentry)) - pr_err("Directory '%s' with parent '%s' already present!\n", - name, parent->d_name.name); - else - pr_err("File '%s' in directory '%s' already present!\n", - name, parent->d_name.name); - dput(dentry); - dentry = ERR_PTR(-EEXIST); - } - - if (IS_ERR(dentry)) { - inode_unlock(d_inode(parent)); - simple_release_fs(&debugfs); - } - - return dentry; -} - -static struct dentry *failed_creating(struct dentry *dentry) -{ - inode_unlock(d_inode(dentry->d_parent)); - dput(dentry); - simple_release_fs(&debugfs); - return ERR_PTR(-ENOMEM); -} - -static struct dentry *end_creating(struct dentry *dentry) -{ - inode_unlock(d_inode(dentry->d_parent)); - return dentry; -} - static struct dentry *__debugfs_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, const struct file_operations *proxy_fops, @@ -375,32 +313,17 @@ static struct dentry *__debugfs_create_file(const char *name, umode_t mode, struct dentry *dentry; struct inode *inode; - if (!(mode & S_IFMT)) - mode |= S_IFREG; - BUG_ON(!S_ISREG(mode)); - dentry = start_creating(name, parent); - + dentry = simplefs_create_file(&debugfs, &debug_fs_type, + name, mode, parent, data, &inode); if (IS_ERR(dentry)) return dentry; - inode = debugfs_get_inode(dentry->d_sb); - if (unlikely(!inode)) { - pr_err("out of free dentries, can not create file '%s'\n", - name); - return failed_creating(dentry); - } - - inode->i_mode = mode; - inode->i_private = data; - inode->i_op = &debugfs_file_inode_operations; inode->i_fop = proxy_fops; dentry->d_fsdata = (void *)((unsigned long)real_fops | DEBUGFS_FSDATA_IS_REAL_FOPS_BIT); - d_instantiate(dentry, inode); - fsnotify_create(d_inode(dentry->d_parent), dentry); - return end_creating(dentry); + return simplefs_finish_dentry(dentry, inode); } /** @@ -533,29 +456,16 @@ EXPORT_SYMBOL_GPL(debugfs_create_file_size); */ struct dentry *debugfs_create_dir(const char *name, struct dentry *parent) { - struct dentry *dentry = start_creating(name, parent); + struct dentry *dentry; struct inode *inode; + dentry = simplefs_create_dir(&debugfs, &debug_fs_type, + name, 0755, parent, &inode); if (IS_ERR(dentry)) return dentry; - inode = debugfs_get_inode(dentry->d_sb); - if (unlikely(!inode)) { - pr_err("out of free dentries, can not create directory '%s'\n", - name); - return failed_creating(dentry); - } - - inode->i_mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; inode->i_op = &debugfs_dir_inode_operations; - inode->i_fop = &simple_dir_operations; - - /* directory inodes start off with i_nlink == 2 (for "." entry) */ - inc_nlink(inode); - d_instantiate(dentry, inode); - inc_nlink(d_inode(dentry->d_parent)); - fsnotify_mkdir(d_inode(dentry->d_parent), dentry); - return end_creating(dentry); + return simplefs_finish_dentry(dentry, inode); } EXPORT_SYMBOL_GPL(debugfs_create_dir); @@ -575,29 +485,19 @@ struct dentry *debugfs_create_automount(const char *name, debugfs_automount_t f, void *data) { - struct dentry *dentry = start_creating(name, parent); + struct dentry *dentry; struct inode *inode; + dentry = simplefs_create_dentry(&debugfs, &debug_fs_type, name, parent, + &inode); if (IS_ERR(dentry)) return dentry; - inode = debugfs_get_inode(dentry->d_sb); - if (unlikely(!inode)) { - pr_err("out of free dentries, can not create automount '%s'\n", - name); - return failed_creating(dentry); - } - make_empty_dir_inode(inode); inode->i_flags |= S_AUTOMOUNT; inode->i_private = data; dentry->d_fsdata = (void *)f; - /* directory inodes start off with i_nlink == 2 (for "." entry) */ - inc_nlink(inode); - d_instantiate(dentry, inode); - inc_nlink(d_inode(dentry->d_parent)); - fsnotify_mkdir(d_inode(dentry->d_parent), dentry); - return end_creating(dentry); + return simplefs_finish_dentry(dentry, inode); } EXPORT_SYMBOL(debugfs_create_automount); @@ -629,28 +529,14 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, { struct dentry *dentry; struct inode *inode; - char *link = kstrdup(target, GFP_KERNEL); - if (!link) - return ERR_PTR(-ENOMEM); - dentry = start_creating(name, parent); - if (IS_ERR(dentry)) { - kfree(link); + dentry = simplefs_create_symlink(&debugfs, &debug_fs_type, + name, parent, target, &inode); + if (IS_ERR(dentry)) return dentry; - } - inode = debugfs_get_inode(dentry->d_sb); - if (unlikely(!inode)) { - pr_err("out of free dentries, can not create symlink '%s'\n", - name); - kfree(link); - return failed_creating(dentry); - } - inode->i_mode = S_IFLNK | S_IRWXUGO; inode->i_op = &debugfs_symlink_inode_operations; - inode->i_link = link; - d_instantiate(dentry, inode); - return end_creating(dentry); + return simplefs_finish_dentry(dentry, inode); } EXPORT_SYMBOL_GPL(debugfs_create_symlink);