#include <linux/smp_lock.h>
#include <linux/personality.h>
#include <linux/security.h>
-#include <linux/syscalls.h>
#include <linux/mount.h>
#include <linux/audit.h>
-#include <linux/proc_fs.h>
-#include <linux/vserver/inode.h>
-#include <linux/vserver/debug.h>
+#include <linux/vs_base.h>
#include <asm/namei.h>
#include <asm/uaccess.h>
return result;
}
-/**
- * generic_permission - check for access rights on a Posix-like filesystem
- * @inode: inode to check access rights for
- * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
- * @check_acl: optional callback to check for Posix ACLs
+/*
+ * vfs_permission()
*
- * Used to check for read/write/execute permissions on a file.
+ * is used to check for read/write/execute permissions on a file.
* We use "fsuid" for this, letting us set arbitrary permissions
* for filesystem access without changing the "normal" uids which
* are used for other things..
*/
-int generic_permission(struct inode *inode, int mask,
- int (*check_acl)(struct inode *inode, int mask))
+int vfs_permission(struct inode * inode, int mask)
{
umode_t mode = inode->i_mode;
+ /* Prevent vservers from escaping chroot() barriers */
+ if (IS_BARRIER(inode) && !vx_check(0, VX_ADMIN))
+ return -EACCES;
+
if (mask & MAY_WRITE) {
/*
* Nobody gets write access to a read-only fs.
if (current->fsuid == inode->i_uid)
mode >>= 6;
- else {
- if (IS_POSIXACL(inode) && (mode & S_IRWXG) && check_acl) {
- int error = check_acl(inode, mask);
- if (error == -EACCES)
- goto check_capabilities;
- else if (error != -EAGAIN)
- return error;
- }
-
- if (in_group_p(inode->i_gid))
- mode >>= 3;
- }
+ else if (in_group_p(inode->i_gid))
+ mode >>= 3;
/*
* If the DACs are ok we don't need any capability check.
if (((mode & mask & (MAY_READ|MAY_WRITE|MAY_EXEC)) == mask))
return 0;
- check_capabilities:
/*
* Read/write DACs are always overridable.
* Executable DACs are overridable if at least one exec bit is set.
return -EACCES;
}
-static inline int xid_permission(struct inode *inode, int mask, struct nameidata *nd)
-{
- if (inode->i_xid == 0)
- return 0;
-
-#ifdef CONFIG_VSERVER_FILESHARING
- /* MEF: PlanetLab FS module assumes that any file that can be
- * named (e.g., via a cross mount) is not hidden from another
- * context or the admin context.
- */
- if (vx_check(inode->i_xid,VX_STATIC|VX_DYNAMIC))
- return 0;
-#endif
- if (vx_check(inode->i_xid,VX_ADMIN|VX_WATCH|VX_IDENT))
- return 0;
-
- vxwprintk(1, "xid=%d denied access to %p[#%d,%lu] »%s«.",
- vx_current_xid(), inode, inode->i_xid, inode->i_ino,
- vxd_path(nd->dentry, nd->mnt));
- return -EACCES;
-}
-
int permission(struct inode * inode,int mask, struct nameidata *nd)
{
int retval;
int submask;
umode_t mode = inode->i_mode;
- /* Prevent vservers from escaping chroot() barriers */
- if (IS_BARRIER(inode) && !vx_check(0, VX_ADMIN))
- return -EACCES;
-
/* Ordinary permission routines do not understand MAY_APPEND. */
submask = mask & ~MAY_APPEND;
(S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
return -EROFS;
- if ((retval = xid_permission(inode, mask, nd)))
- return retval;
-
if (inode->i_op && inode->i_op->permission)
retval = inode->i_op->permission(inode, submask, nd);
else
- retval = generic_permission(inode, submask, NULL);
+ retval = vfs_permission(inode, submask);
if (retval)
return retval;
/*
* Short-cut version of permission(), for calling by
* path_walk(), when dcache lock is held. Combines parts
- * of permission() and generic_permission(), and tests ONLY for
+ * of permission() and vfs_permission(), and tests ONLY for
* MAY_EXEC permission.
*
* If appropriate, check DAC only. If not appropriate, or
{
struct vfsmount *mnt = nd->mnt;
struct dentry *dentry = __d_lookup(nd->dentry, name);
- struct inode *inode;
if (!dentry)
goto need_lookup;
if (dentry->d_op && dentry->d_op->d_revalidate)
goto need_revalidate;
- inode = dentry->d_inode;
- if (!inode)
- goto done;
- if (inode->i_sb->s_magic == PROC_SUPER_MAGIC) {
- struct proc_dir_entry *de = PDE(inode);
-
- if (de && !vx_hide_check(0, de->vx_flags))
- goto hidden;
- }
-#ifdef CONFIG_VSERVER_FILESHARING
- /* MEF: PlanetLab FS module assumes that any file that can be
- * named (e.g., via a cross mount) is not hidden from another
- * context or the admin context.
- */
- if (vx_check(inode->i_xid,VX_STATIC|VX_DYNAMIC|VX_ADMIN)) {
- /* do nothing */
- }
- else /* do the following check */
-#endif
- if (!vx_check(inode->i_xid,
- VX_WATCH|
- VX_HOSTID|
- VX_IDENT))
- goto hidden;
done:
path->mnt = mnt;
path->dentry = dentry;
return 0;
-hidden:
- vxwprintk(1, "xid=%d did lookup hidden %p[#%d,%lu] »%s«.",
- vx_current_xid(), inode, inode->i_xid, inode->i_ino,
- vxd_path(dentry, mnt));
- dput(dentry);
- return -ENOENT;
need_lookup:
if (atomic)
EXPORT_SYMBOL(vfs_link);
EXPORT_SYMBOL(vfs_mkdir);
EXPORT_SYMBOL(vfs_mknod);
-EXPORT_SYMBOL(generic_permission);
+EXPORT_SYMBOL(vfs_permission);
EXPORT_SYMBOL(vfs_readlink);
EXPORT_SYMBOL(vfs_rename);
EXPORT_SYMBOL(vfs_rmdir);
git://git.onelab.eu / linux-2.6.git / blobdiff