[PATCH v23 01/22] vfs: Add IS_ACL() and IS_RICHACL() tests

Andreas Gruenbacher
2016-06-30T13:56:24Z

The vfs does not apply the umask for file systems that support acls.
The test used for this used to be called IS_POSIXACL(). Switch to a new
IS_ACL() test to check for either posix acls or richacls instead. Add a
new MS_RICHACL flag and IS_RICHACL() test for richacls alone. The
IS_POSIXACL() test is still needed in some places like nfsd.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Steve French <steve.french@primarydata.com>
---
fs/Kconfig | 3 +++
fs/namei.c | 6 +++---
include/linux/fs.h | 12 ++++++++++++
include/uapi/linux/fs.h | 3 ++-
4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/fs/Kconfig b/fs/Kconfig
index b8fcb41..de6de55 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -64,6 +64,9 @@ endif # BLOCK
config FS_POSIX_ACL
def_bool n

+config FS_RICHACL
+ def_bool n
+
config EXPORTFS
tristate

diff --git a/fs/namei.c b/fs/namei.c
index 70580ab..7cc5487 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3115,7 +3115,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
* O_EXCL open we want to return EEXIST not EROFS).
*/
if (open_flag & O_CREAT) {
- if (!IS_POSIXACL(dir->d_inode))
+ if (!IS_ACL(dir->d_inode))
mode &= ~current_umask();
if (unlikely(!got_write)) {
create_error = -EROFS;
@@ -3709,7 +3709,7 @@ retry:
if (IS_ERR(dentry))
return PTR_ERR(dentry);

- if (!IS_POSIXACL(path.dentry->d_inode))
+ if (!IS_ACL(path.dentry->d_inode))
mode &= ~current_umask();
error = security_path_mknod(&path, dentry, mode, dev);
if (error)
@@ -3780,7 +3780,7 @@ retry:
if (IS_ERR(dentry))
return PTR_ERR(dentry);

- if (!IS_POSIXACL(path.dentry->d_inode))
+ if (!IS_ACL(path.dentry->d_inode))
mode &= ~current_umask();
error = security_path_mkdir(&path, dentry, mode);
if (!error)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index dd28814..4ad130c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1850,6 +1850,12 @@ struct super_operations {
#define IS_IMMUTABLE(inode) ((inode)->i_flags & S_IMMUTABLE)
#define IS_POSIXACL(inode) __IS_FLG(inode, MS_POSIXACL)

+#ifdef CONFIG_FS_RICHACL
+#define IS_RICHACL(inode) __IS_FLG(inode, MS_RICHACL)
+#else
+#define IS_RICHACL(inode) 0
+#endif
+
#define IS_DEADDIR(inode) ((inode)->i_flags & S_DEAD)
#define IS_NOCMTIME(inode) ((inode)->i_flags & S_NOCMTIME)
#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
@@ -1863,6 +1869,12 @@ struct super_operations {
(inode)->i_rdev == WHITEOUT_DEV)

/*
+ * IS_ACL() tells the VFS to not apply the umask
+ * and use check_acl for acl permission checks when defined.
+ */
+#define IS_ACL(inode) __IS_FLG(inode, MS_POSIXACL | MS_RICHACL)
+
+/*
* Inode state bits. Protected by inode->i_lock
*
* Three bits determine the dirty state of the inode, I_DIRTY_SYNC,
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 3b00f7c..f9c41ef 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -120,7 +120,7 @@ struct inodes_stat_t {
#define MS_VERBOSE 32768 /* War is peace. Verbosity is silence.
MS_VERBOSE is deprecated. */
#define MS_SILENT 32768
-#define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
+#define MS_POSIXACL (1<<16) /* Supports POSIX ACLs */
#define MS_UNBINDABLE (1<<17) /* change to unbindable */
#define MS_PRIVATE (1<<18) /* change to private */
#define MS_SLAVE (1<<19) /* change to slave */
@@ -130,6 +130,7 @@ struct inodes_stat_t {
#define MS_I_VERSION (1<<23) /* Update inode I_version field */
#define MS_STRICTATIME (1<<24) /* Always perform atime updates */
#define MS_LAZYTIME (1<<25) /* Update the on-disk [acm]times lazily */
+#define MS_RICHACL (1<<26) /* Supports richacls */

/* These sb flags are internal to the kernel */
#define MS_NOSEC (1<<28)
--
2.5.5