[PATCH -V2 02/16] vfs: Add generic IS_ACL() test for acl support

Aneesh Kumar K.V
2010-07-02T18:44:34Z

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@suse.de>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
fs/namei.c | 6 +++---
fs/nfs/nfs4proc.c | 2 +-
include/linux/fs.h | 8 +++++++-
3 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 29e3461..a8d19ab 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1554,7 +1554,7 @@ static int __open_namei_create(struct nameidata *nd, struct path *path,
int error;
struct dentry *dir = nd->path.dentry;

- if (!IS_POSIXACL(dir->d_inode))
+ if (!IS_ACL(dir->d_inode))
mode &= ~current_umask();
error = security_path_mknod(&nd->path, path->dentry, mode, 0);
if (error)
@@ -2077,7 +2077,7 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, int, mode,
error = PTR_ERR(dentry);
goto out_unlock;
}
- if (!IS_POSIXACL(nd.path.dentry->d_inode))
+ if (!IS_ACL(nd.path.dentry->d_inode))
mode &= ~current_umask();
error = may_mknod(mode);
if (error)
@@ -2154,7 +2154,7 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, int, mode)
if (IS_ERR(dentry))
goto out_unlock;

- if (!IS_POSIXACL(nd.path.dentry->d_inode))
+ if (!IS_ACL(nd.path.dentry->d_inode))
mode &= ~current_umask();
error = mnt_want_write(nd.path.mnt);
if (error)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 70015dd..aa8a694 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2028,7 +2028,7 @@ nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
if (nd->flags & LOOKUP_CREATE) {
attr.ia_mode = nd->intent.open.create_mode;
attr.ia_valid = ATTR_MODE;
- if (!IS_POSIXACL(dir))
+ if (!IS_ACL(dir))
attr.ia_mode &= ~current_umask();
} else {
attr.ia_valid = 0;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1ecb3a2..f49dd5c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -200,7 +200,7 @@ 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 */
@@ -270,6 +270,12 @@ struct inodes_stat_t {
#define IS_SWAPFILE(inode) ((inode)->i_flags & S_SWAPFILE)
#define IS_PRIVATE(inode) ((inode)->i_flags & S_PRIVATE)

+/*
+ * IS_ACL() tells the VFS to not apply the umask
+ * and use iop->check_acl for acl permission checks when defined.
+ */
+#define IS_ACL(inode) __IS_FLG(inode, MS_POSIXACL)
+
/* the read-only stuff doesn't really belong here, but any other place is
probably as bad and I don't want to create yet another include file. */

--
1.7.2.rc1