From: Miklos Szeredi <mszeredi@xxxxxxx>
Move most calls of dentry_permission() to path_permission(). The
remaining few uses are all in namei.c, so dentry_permission() can be
made static, further simplifying the API.
This will have the side effect, that MNT_NOEXEC checking on the mount
will be performed for these callers as well. But this should not
cause any problems.
At this point file_permission() is just a helper for
path_permission(), so remove comment about not being preferred.
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx>
---
fs/ecryptfs/inode.c | 7 +++++--
fs/namei.c | 12 +++---------
fs/nfsd/nfsfh.c | 11 ++++++-----
fs/nfsd/vfs.c | 8 ++++++--
fs/xattr.c | 22 ++++++++++++----------
include/linux/fs.h | 1 -
ipc/mqueue.c | 15 +++++++++------
7 files changed, 41 insertions(+), 35 deletions(-)
Index: linux-2.6/fs/ecryptfs/inode.c
===================================================================
--- linux-2.6.orig/fs/ecryptfs/inode.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/fs/ecryptfs/inode.c 2008-05-21 18:17:08.000000000 +0200
@@ -810,9 +810,12 @@ out:
static int
ecryptfs_permission(struct dentry *dentry, int mask, int flags)
{
- struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
+ struct path lower_path;
+
+ lower_path.mnt = ecryptfs_dentry_to_lower_mnt(dentry);
+ lower_path.dentry = ecryptfs_dentry_to_lower(dentry);
- return dentry_permission(lower_dentry, mask, flags);
+ return path_permission(&lower_path, mask, flags);
}
/**
Index: linux-2.6/fs/namei.c
===================================================================
--- linux-2.6.orig/fs/namei.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/fs/namei.c 2008-05-21 18:17:08.000000000 +0200
@@ -246,7 +246,7 @@ int exec_permission(struct inode *inode,
return 0;
}
-int dentry_permission(struct dentry *dentry, int mask, int flags)
+static int dentry_permission(struct dentry *dentry, int mask, int flags)
{
struct inode *inode = dentry->d_inode;
int retval, submask;
@@ -320,16 +320,11 @@ int path_permission(struct path *path, i
* @file: file to check access rights for
* @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
*
- * Used to check for read/write/execute permissions on an already opened
- * file.
- *
- * Note:
- * Do not use this function in new code. All access checks should
- * be done using path_permission().
+ * This is a helper for path_permission().
*/
int file_permission(struct file *file, int mask)
{
- return dentry_permission(file->f_path.dentry, mask, 0);
+ return path_permission(&file->f_path, mask, 0);
}
/*
@@ -3061,7 +3056,6 @@ EXPORT_SYMBOL(page_symlink);
EXPORT_SYMBOL(page_symlink_inode_operations);
EXPORT_SYMBOL(path_lookup);
EXPORT_SYMBOL(vfs_path_lookup);
-EXPORT_SYMBOL(dentry_permission);
EXPORT_SYMBOL(path_permission);
EXPORT_SYMBOL(file_permission);
EXPORT_SYMBOL(unlock_rename);
Index: linux-2.6/fs/nfsd/nfsfh.c
===================================================================
--- linux-2.6.orig/fs/nfsd/nfsfh.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/fs/nfsd/nfsfh.c 2008-05-21 18:17:08.000000000 +0200
@@ -41,7 +41,7 @@ static int nfsd_acceptable(void *expv, s
struct svc_export *exp = expv;
int rv;
struct dentry *tdentry;
- struct dentry *parent;
+ struct path parent = { .mnt = exp->ex_path.mnt };
if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
return 1;
@@ -50,14 +50,15 @@ static int nfsd_acceptable(void *expv, s
while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
/* make sure parents give x permission to user */
int err;
- parent = dget_parent(tdentry);
- err = dentry_permission(parent, MAY_EXEC, 0);
+
+ parent.dentry = dget_parent(tdentry);
+ err = path_permission(&parent, MAY_EXEC, 0);
if (err < 0) {
- dput(parent);
+ dput(parent.dentry);
break;
}
dput(tdentry);
- tdentry = parent;
+ tdentry = parent.dentry;
}
if (tdentry != exp->ex_path.dentry)
dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
Index: linux-2.6/fs/nfsd/vfs.c
===================================================================
--- linux-2.6.orig/fs/nfsd/vfs.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/fs/nfsd/vfs.c 2008-05-21 18:17:08.000000000 +0200
@@ -1878,6 +1878,10 @@ nfsd_permission(struct svc_rqst *rqstp,
{
struct inode *inode = dentry->d_inode;
int err;
+ struct path path = {
+ .mnt = exp->ex_path.mnt,
+ .dentry = dentry,
+ };
if (acc == MAY_NOP)
return 0;
@@ -1942,12 +1946,12 @@ nfsd_permission(struct svc_rqst *rqstp,
inode->i_uid == current->fsuid)
return 0;
- err = dentry_permission(dentry, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), 0);
+ err = path_permission(&path, acc & (MAY_READ|MAY_WRITE|MAY_EXEC), 0);
/* Allow read access to binaries even when mode 111 */
if (err == -EACCES && S_ISREG(inode->i_mode) &&
acc == (MAY_READ | MAY_OWNER_OVERRIDE))
- err = dentry_permission(dentry, MAY_EXEC, 0);
+ err = path_permission(&path, MAY_EXEC, 0);
return err? nfserrno(err) : 0;
}
Index: linux-2.6/ipc/mqueue.c
===================================================================
--- linux-2.6.orig/ipc/mqueue.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/ipc/mqueue.c 2008-05-21 18:17:08.000000000 +0200
@@ -647,19 +647,22 @@ static struct file *do_open(struct dentr
static int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE,
MAY_READ | MAY_WRITE };
+ struct path path = {
+ .mnt = mqueue_mnt,
+ .dentry = dentry,
+ };
+
if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) {
- dput(dentry);
- mntput(mqueue_mnt);
+ path_put(&path);
return ERR_PTR(-EINVAL);
}
- if (dentry_permission(dentry, oflag2acc[oflag & O_ACCMODE], 0)) {
- dput(dentry);
- mntput(mqueue_mnt);
+ if (path_permission(&path, oflag2acc[oflag & O_ACCMODE], 0)) {
+ path_put(&path);
return ERR_PTR(-EACCES);
}
- return dentry_open(dentry, mqueue_mnt, oflag);
+ return dentry_open(path.dentry, path.mnt, oflag);
}
asmlinkage long sys_mq_open(const char __user *u_name, int oflag, mode_t mode,
Index: linux-2.6/fs/xattr.c
===================================================================
--- linux-2.6.orig/fs/xattr.c 2008-05-21 18:16:31.000000000 +0200
+++ linux-2.6/fs/xattr.c 2008-05-21 18:17:08.000000000 +0200
@@ -26,9 +26,9 @@
* because different namespaces have very different rules.
*/
static int
-xattr_permission(struct dentry *dentry, const char *name, int mask)
+xattr_permission(struct path *path, const char *name, int mask)
{
- struct inode *inode = dentry->d_inode;
+ struct inode *inode = path->dentry->d_inode;
/*
* We can never set or remove an extended attribute on a read-only
@@ -65,17 +65,18 @@ xattr_permission(struct dentry *dentry,
return -EPERM;
}
- return dentry_permission(dentry, mask, 0);
+ return path_permission(path, mask, 0);
}
static int
-vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+vfs_setxattr(struct path *path, const char *name, const void *value,
size_t size, int flags)
{
+ struct dentry *dentry = path->dentry;
struct inode *inode = dentry->d_inode;
int error;
- error = xattr_permission(dentry, name, MAY_WRITE);
+ error = xattr_permission(path, name, MAY_WRITE);
if (error)
return error;
@@ -110,7 +111,7 @@ int path_setxattr(struct path *path, con
int error = mnt_want_write(path->mnt);
if (!error) {
- error = vfs_setxattr(path->dentry, name, value, size, flags);
+ error = vfs_setxattr(path, name, value, size, flags);
mnt_drop_write(path->mnt);
}
@@ -152,7 +153,7 @@ path_getxattr(struct path *path, const c
struct inode *inode = dentry->d_inode;
int error;
- error = xattr_permission(dentry, name, MAY_READ);
+ error = xattr_permission(path, name, MAY_READ);
if (error)
return error;
@@ -204,15 +205,16 @@ path_listxattr(struct path *path, char *
EXPORT_SYMBOL_GPL(path_listxattr);
static int
-vfs_removexattr(struct dentry *dentry, const char *name)
+vfs_removexattr(struct path *path, const char *name)
{
+ struct dentry *dentry = path->dentry;
struct inode *inode = dentry->d_inode;
int error;
if (!inode->i_op->removexattr)
return -EOPNOTSUPP;
- error = xattr_permission(dentry, name, MAY_WRITE);
+ error = xattr_permission(path, name, MAY_WRITE);
if (error)
return error;
@@ -234,7 +236,7 @@ int path_removexattr(struct path *path,
int error = mnt_want_write(path->mnt);
if (!error) {
- error = vfs_removexattr(path->dentry, name);
+ error = vfs_removexattr(path, name);
mnt_drop_write(path->mnt);
}
Index: linux-2.6/include/linux/fs.h
===================================================================
--- linux-2.6.orig/include/linux/fs.h 2008-05-21 18:15:02.000000000 +0200
+++ linux-2.6/include/linux/fs.h 2008-05-21 18:17:08.000000000 +0200
@@ -1758,7 +1758,6 @@ extern sector_t bmap(struct inode *, sec
#endif
extern int notify_change(struct dentry *, struct iattr *);
extern int path_setattr(struct path *, struct iattr *);
-extern int dentry_permission(struct dentry *, int, int);
extern int generic_permission(struct inode *, int,
int (*check_acl)(struct inode *, int));
extern int exec_permission(struct inode *, int);
--
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
