NFS: Fix handling of the umask when an NFSv3 default acl is present. NFSv3 has no concept of a umask on the server side: The client applies the umask locally, and sends the effective permissions to the server. This behavior is wrong when files are created in a directory that has a default ACL. In this case, the umask is supposed to be ignored, and only the default ACL determines the file's effective permissions. Usually its the server's task to conditionally apply the umask. But since the server knows nothing about the umask, we have to do it on the client side. This patch tries to fetch the parent directory's default ACL before creating a new file, computes the appropriate create mode to send to the server, and finally sets the new file's access and default acl appropriately. Many thanks to Buck Huppmann for sending the initial version of this patch, as well as for arguing why we need this change. Signed-off-by: Andreas Gruenbacher Acked-by: Olaf Kirch Signed-off-by: Andrew Morton Signed-off-by: Trond Myklebust --- fs/nfs/inode.c | 5 +++++ fs/nfs/nfs3acl.c | 29 +++++++++++++++++++++++++++++ fs/nfs/nfs3proc.c | 36 ++++++++++++++++++++++++++++++------ include/linux/nfs_fs.h | 9 +++++++++ 4 files changed, 73 insertions(+), 6 deletions(-) Index: linux-2.6.12-rc1/fs/nfs/nfs3proc.c =================================================================== --- linux-2.6.12-rc1.orig/fs/nfs/nfs3proc.c +++ linux-2.6.12-rc1/fs/nfs/nfs3proc.c @@ -314,7 +314,8 @@ nfs3_proc_create(struct inode *dir, stru .fh = &fhandle, .fattr = &fattr }; - int status; + mode_t mode = sattr->ia_mode; + int status; dprintk("NFS call create %s\n", dentry->d_name.name); arg.createmode = NFS3_CREATE_UNCHECKED; @@ -324,6 +325,8 @@ nfs3_proc_create(struct inode *dir, stru arg.verifier[1] = current->pid; } + sattr->ia_mode &= ~current->fs->umask; + again: dir_attr.valid = 0; fattr.valid = 0; @@ -370,6 +373,9 @@ again: nfs_refresh_inode(dentry->d_inode, &fattr); dprintk("NFS reply setattr (post-create): %d\n", status); } + if (status != 0) + goto out; + status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode); out: dprintk("NFS reply create: %d\n", status); return status; @@ -539,15 +545,24 @@ nfs3_proc_mkdir(struct inode *dir, struc .fh = &fhandle, .fattr = &fattr }; - int status; + int mode = sattr->ia_mode; + int status; dprintk("NFS call mkdir %s\n", dentry->d_name.name); dir_attr.valid = 0; fattr.valid = 0; + + sattr->ia_mode &= ~current->fs->umask; + status = rpc_call(NFS_CLIENT(dir), NFS3PROC_MKDIR, &arg, &res, 0); nfs_refresh_inode(dir, &dir_attr); - if (status == 0) - status = nfs_instantiate(dentry, &fhandle, &fattr); + if (status != 0) + goto out; + status = nfs_instantiate(dentry, &fhandle, &fattr); + if (status != 0) + goto out; + status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode); +out: dprintk("NFS reply mkdir: %d\n", status); return status; } @@ -642,6 +657,7 @@ nfs3_proc_mknod(struct inode *dir, struc .fh = &fh, .fattr = &fattr }; + mode_t mode = sattr->ia_mode; int status; switch (sattr->ia_mode & S_IFMT) { @@ -654,12 +670,20 @@ nfs3_proc_mknod(struct inode *dir, struc dprintk("NFS call mknod %s %u:%u\n", dentry->d_name.name, MAJOR(rdev), MINOR(rdev)); + + sattr->ia_mode &= ~current->fs->umask; + dir_attr.valid = 0; fattr.valid = 0; status = rpc_call(NFS_CLIENT(dir), NFS3PROC_MKNOD, &arg, &res, 0); nfs_refresh_inode(dir, &dir_attr); - if (status == 0) - status = nfs_instantiate(dentry, &fh, &fattr); + if (status != 0) + goto out; + status = nfs_instantiate(dentry, &fh, &fattr); + if (status != 0) + goto out; + status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode); +out: dprintk("NFS reply mknod: %d\n", status); return status; } Index: linux-2.6.12-rc1/fs/nfs/nfs3acl.c =================================================================== --- linux-2.6.12-rc1.orig/fs/nfs/nfs3acl.c +++ linux-2.6.12-rc1/fs/nfs/nfs3acl.c @@ -301,3 +301,32 @@ int nfs3_proc_setacl(struct inode *inode fail: return PTR_ERR(alloc); } + +int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode, + mode_t mode) +{ + struct posix_acl *dfacl, *acl; + int error = 0; + + dfacl = nfs3_proc_getacl(dir, ACL_TYPE_DEFAULT); + if (IS_ERR(dfacl)) { + error = PTR_ERR(dfacl); + return (error == -EOPNOTSUPP) ? 0 : error; + } + if (!dfacl) + return 0; + acl = posix_acl_clone(dfacl, GFP_KERNEL); + error = -ENOMEM; + if (!acl) + goto out_release_dfacl; + error = posix_acl_create_masq(acl, &mode); + if (error < 0) + goto out_release_acl; + error = nfs3_proc_setacls(inode, acl, S_ISDIR(inode->i_mode) ? + dfacl : NULL); +out_release_acl: + posix_acl_release(acl); +out_release_dfacl: + posix_acl_release(dfacl); + return error; +} Index: linux-2.6.12-rc1/include/linux/nfs_fs.h =================================================================== --- linux-2.6.12-rc1.orig/include/linux/nfs_fs.h +++ linux-2.6.12-rc1/include/linux/nfs_fs.h @@ -478,6 +478,15 @@ extern void nfs_readdata_release(struct extern struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type); extern int nfs3_proc_setacl(struct inode *inode, int type, struct posix_acl *acl); +extern int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode, + mode_t mode); +#else +static inline int nfs3_proc_set_default_acl(struct inode *dir, + struct inode *inode, + mode_t mode) +{ + return 0; +} #endif /* CONFIG_NFS_V3_ACL */ /* Index: linux-2.6.12-rc1/fs/nfs/inode.c =================================================================== --- linux-2.6.12-rc1.orig/fs/nfs/inode.c +++ linux-2.6.12-rc1/fs/nfs/inode.c @@ -490,6 +490,11 @@ nfs_fill_super(struct super_block *sb, s #else server->flags &= ~NFS_MOUNT_NOACL; #endif /* CONFIG_NFS_V3_ACL */ + /* + * The VFS shouldn't apply the umask to mode bits. We will + * do so ourselves when necessary. + */ + sb->s_flags |= MS_POSIXACL; if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN) server->namelen = NFS3_MAXNAMLEN; sb->s_time_gran = 1;