[PATCH v11 01/48] vfs: Add IS_ACL() and IS_RICHACL() tests

Andreas Gruenbacher
2015-10-16T15:18:43Z

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 by nfsd.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: J. Bruce Fields <bfields@redhat.com>
---
fs/Kconfig | 3 +++
fs/namei.c | 8 ++++----
include/linux/fs.h | 12 ++++++++++++
include/uapi/linux/fs.h | 3 ++-
4 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/fs/Kconfig b/fs/Kconfig
index da3f32f..bff2879 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -56,6 +56,9 @@ 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 33e9495..224ecf1 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2798,7 +2798,7 @@ static int atomic_open(struct nameidata *nd, struct dentry *dentry,
}

mode = op->mode;
- if ((open_flag & O_CREAT) && !IS_POSIXACL(dir))
+ if ((open_flag & O_CREAT) && !IS_ACL(dir))
mode &= ~current_umask();

excl = (open_flag & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT);
@@ -2982,7 +2982,7 @@ static int lookup_open(struct nameidata *nd, struct path *path,
/* Negative dentry, just create the file */
if (!dentry->d_inode && (op->open_flag & O_CREAT)) {
umode_t mode = op->mode;
- if (!IS_POSIXACL(dir->d_inode))
+ if (!IS_ACL(dir->d_inode))
mode &= ~current_umask();
/*
* This write is needed to ensure that a
@@ -3553,7 +3553,7 @@ 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)
@@ -3622,7 +3622,7 @@ 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 72d8a84..4efa435 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1781,6 +1781,12 @@ 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)
@@ -1794,6 +1800,12 @@ 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 9b964a5..6ac6bc9 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -81,7 +81,7 @@ 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 */
@@ -91,6 +91,7 @@ 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)