From patchwork Wed Feb 23 13:51:54 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Aneesh Kumar K.V" X-Patchwork-Id: 584471 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p1NDsbb6024983 for ; Wed, 23 Feb 2011 13:54:37 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932142Ab1BWNxl (ORCPT ); Wed, 23 Feb 2011 08:53:41 -0500 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:52542 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932138Ab1BWNxi (ORCPT ); Wed, 23 Feb 2011 08:53:38 -0500 Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp06.in.ibm.com (8.14.4/8.13.1) with ESMTP id p1NDrWLR027671; Wed, 23 Feb 2011 19:23:32 +0530 Received: from d28av05.in.ibm.com (d28av05.in.ibm.com [9.184.220.67]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p1NDrVB31741030; Wed, 23 Feb 2011 19:23:31 +0530 Received: from d28av05.in.ibm.com (loopback [127.0.0.1]) by d28av05.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p1NDr7QG017407; Thu, 24 Feb 2011 00:53:09 +1100 Received: from skywalker.ibm.com ([9.77.68.27]) by d28av05.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p1NDqS20014791; Thu, 24 Feb 2011 00:53:04 +1100 From: "Aneesh Kumar K.V" To: sfrench@us.ibm.com, agruen@linbit.com, dilger.kernel@dilger.ca, sandeen@redhat.com, tytso@mit.edu, bfields@fieldses.org, jlayton@redhat.com Cc: aneesh.kumar@linux.vnet.ibm.com, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Andreas Gruenbacher Subject: [PATCH -V5 07/24] vfs: Add new file and directory create permission flags Date: Wed, 23 Feb 2011 19:21:54 +0530 Message-Id: <1298469131-16555-8-git-send-email-aneesh.kumar@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1298469131-16555-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> References: <1298469131-16555-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Wed, 23 Feb 2011 13:54:37 +0000 (UTC) diff --git a/fs/namei.c b/fs/namei.c index b1e5104..b4f7198 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -252,7 +252,8 @@ int generic_permission(struct inode *inode, int mask, unsigned int flags, * for filesystem access without changing the "normal" uids which * are used for other things. * - * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask. + * When checking for MAY_APPEND, MAY_CREATE_FILE, MAY_CREATE_DIR, + * MAY_WRITE must also be set in @mask. */ int inode_permission(struct inode *inode, int mask) { @@ -2005,13 +2006,15 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir) * 3. We should have write and exec permissions on dir * 4. We can't do it if dir is immutable (done in permission()) */ -static inline int may_create(struct inode *dir, struct dentry *child) +static inline int may_create(struct inode *dir, struct dentry *child, int isdir) { + int mask = isdir ? MAY_CREATE_DIR : MAY_CREATE_FILE; + if (child->d_inode) return -EEXIST; if (IS_DEADDIR(dir)) return -ENOENT; - return inode_permission(dir, MAY_WRITE | MAY_EXEC); + return inode_permission(dir, MAY_WRITE | MAY_EXEC | mask); } /* @@ -2059,7 +2062,7 @@ void unlock_rename(struct dentry *p1, struct dentry *p2) int vfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) { - int error = may_create(dir, dentry); + int error = may_create(dir, dentry, 0); if (error) return error; @@ -2629,7 +2632,7 @@ EXPORT_SYMBOL_GPL(lookup_create); int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) { - int error = may_create(dir, dentry); + int error = may_create(dir, dentry, 0); if (error) return error; @@ -2733,7 +2736,7 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, int, mode, unsigned, dev) int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) { - int error = may_create(dir, dentry); + int error = may_create(dir, dentry, 1); if (error) return error; @@ -3016,7 +3019,7 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname) int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) { - int error = may_create(dir, dentry); + int error = may_create(dir, dentry, 0); if (error) return error; @@ -3089,7 +3092,10 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de if (!inode) return -ENOENT; - error = may_create(dir, new_dentry); + if (S_ISDIR(inode->i_mode)) + return -EPERM; + + error = may_create(dir, new_dentry, 0); if (error) return error; @@ -3103,8 +3109,6 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de return -EPERM; if (!dir->i_op->link) return -EPERM; - if (S_ISDIR(inode->i_mode)) - return -EPERM; error = security_inode_link(old_dentry, dir, new_dentry); if (error) @@ -3305,7 +3309,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, return error; if (!new_dentry->d_inode) - error = may_create(new_dir, new_dentry); + error = may_create(new_dir, new_dentry, is_dir); else error = may_delete(new_dir, new_dentry, is_dir); if (error) diff --git a/include/linux/fs.h b/include/linux/fs.h index 1dc6e72..a86afc0 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -62,6 +62,8 @@ struct inodes_stat_t { #define MAY_ACCESS 16 #define MAY_OPEN 32 #define MAY_CHDIR 64 +#define MAY_CREATE_FILE 128 +#define MAY_CREATE_DIR 256 /* * flags in file.f_mode. Note that FMODE_READ and FMODE_WRITE must correspond