[PATCH -V1 01/22] vfs: Add generic IS_ACL() test for acl support

Aneesh Kumar K.V
2014-04-27T16:15:57Z

From: Andreas Gruenbacher <agruen@kernel.org>

When IS_POSIXACL() is true, the vfs does not apply the umask. Other acl
models will need the same exception, so introduce a separate IS_ACL()
test.

The IS_POSIX_ACL() test is still needed so that nfsd can determine when
the underlying file system supports POSIX ACLs (as opposed to some other
kind).

Signed-off-by: Andreas Gruenbacher <agruen@kernel.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
fs/namei.c | 8 ++++----
include/linux/fs.h | 6 ++++++
include/uapi/linux/fs.h | 2 +-
3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index c6157c894fce..c7fee619691f 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2650,7 +2650,7 @@ 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);
@@ -2834,7 +2834,7 @@ 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
@@ -3422,7 +3422,7 @@ 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)
@@ -3491,7 +3491,7 @@ 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 7a9c5bca2b76..9fb63b71a014 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1611,6 +1611,12 @@ struct super_operations {
#define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)

/*
+ * 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)
+
+/*
* 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 ca1a11bb4443..1e14b9c82703 100644
--- a/include/uapi/linux/fs.h
+++ b/include/uapi/linux/fs.h
@@ -80,7 +80,7 @@ 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 */
--
1.9.1