mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![James Morris](/assets/img/avatar_default.png)
Prevent permission checking from being performed when the kernel wants to unconditionally remove a sysfs group, by introducing an kernel-only variant of lookup_one_len(), lookup_one_len_kern(). Additionally, as sysfs_remove_group() does not check the return value of the lookup before using it, a BUG_ON has been added to pinpoint the cause of any problems potentially caused by this (and as a form of annotation). Signed-off-by: James Morris <jmorris@namei.org> Cc: Nagendra Singh Tomar <nagendra_tomar@adaptec.com> Cc: Tejun Heo <htejun@gmail.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
103 lines
3 KiB
C
103 lines
3 KiB
C
#ifndef _LINUX_NAMEI_H
|
|
#define _LINUX_NAMEI_H
|
|
|
|
#include <linux/dcache.h>
|
|
#include <linux/linkage.h>
|
|
|
|
struct vfsmount;
|
|
|
|
struct open_intent {
|
|
int flags;
|
|
int create_mode;
|
|
struct file *file;
|
|
};
|
|
|
|
enum { MAX_NESTED_LINKS = 8 };
|
|
|
|
struct nameidata {
|
|
struct dentry *dentry;
|
|
struct vfsmount *mnt;
|
|
struct qstr last;
|
|
unsigned int flags;
|
|
int last_type;
|
|
unsigned depth;
|
|
char *saved_names[MAX_NESTED_LINKS + 1];
|
|
|
|
/* Intent data */
|
|
union {
|
|
struct open_intent open;
|
|
} intent;
|
|
};
|
|
|
|
struct path {
|
|
struct vfsmount *mnt;
|
|
struct dentry *dentry;
|
|
};
|
|
|
|
/*
|
|
* Type of the last component on LOOKUP_PARENT
|
|
*/
|
|
enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
|
|
|
|
/*
|
|
* The bitmask for a lookup event:
|
|
* - follow links at the end
|
|
* - require a directory
|
|
* - ending slashes ok even for nonexistent files
|
|
* - internal "there are more path compnents" flag
|
|
* - locked when lookup done with dcache_lock held
|
|
* - dentry cache is untrusted; force a real lookup
|
|
*/
|
|
#define LOOKUP_FOLLOW 1
|
|
#define LOOKUP_DIRECTORY 2
|
|
#define LOOKUP_CONTINUE 4
|
|
#define LOOKUP_PARENT 16
|
|
#define LOOKUP_NOALT 32
|
|
#define LOOKUP_REVAL 64
|
|
/*
|
|
* Intent data
|
|
*/
|
|
#define LOOKUP_OPEN (0x0100)
|
|
#define LOOKUP_CREATE (0x0200)
|
|
#define LOOKUP_ACCESS (0x0400)
|
|
#define LOOKUP_CHDIR (0x0800)
|
|
|
|
extern int FASTCALL(__user_walk(const char __user *, unsigned, struct nameidata *));
|
|
extern int FASTCALL(__user_walk_fd(int dfd, const char __user *, unsigned, struct nameidata *));
|
|
#define user_path_walk(name,nd) \
|
|
__user_walk_fd(AT_FDCWD, name, LOOKUP_FOLLOW, nd)
|
|
#define user_path_walk_link(name,nd) \
|
|
__user_walk_fd(AT_FDCWD, name, 0, nd)
|
|
extern int FASTCALL(path_lookup(const char *, unsigned, struct nameidata *));
|
|
extern int FASTCALL(path_walk(const char *, struct nameidata *));
|
|
extern int FASTCALL(link_path_walk(const char *, struct nameidata *));
|
|
extern void path_release(struct nameidata *);
|
|
extern void path_release_on_umount(struct nameidata *);
|
|
|
|
extern int __user_path_lookup_open(const char __user *, unsigned lookup_flags, struct nameidata *nd, int open_flags);
|
|
extern int path_lookup_open(int dfd, const char *name, unsigned lookup_flags, struct nameidata *, int open_flags);
|
|
extern struct file *lookup_instantiate_filp(struct nameidata *nd, struct dentry *dentry,
|
|
int (*open)(struct inode *, struct file *));
|
|
extern struct file *nameidata_to_filp(struct nameidata *nd, int flags);
|
|
extern void release_open_intent(struct nameidata *);
|
|
|
|
extern struct dentry * lookup_one_len(const char *, struct dentry *, int);
|
|
extern struct dentry *lookup_one_len_kern(const char *, struct dentry *, int);
|
|
|
|
extern int follow_down(struct vfsmount **, struct dentry **);
|
|
extern int follow_up(struct vfsmount **, struct dentry **);
|
|
|
|
extern struct dentry *lock_rename(struct dentry *, struct dentry *);
|
|
extern void unlock_rename(struct dentry *, struct dentry *);
|
|
|
|
static inline void nd_set_link(struct nameidata *nd, char *path)
|
|
{
|
|
nd->saved_names[nd->depth] = path;
|
|
}
|
|
|
|
static inline char *nd_get_link(struct nameidata *nd)
|
|
{
|
|
return nd->saved_names[nd->depth];
|
|
}
|
|
|
|
#endif /* _LINUX_NAMEI_H */
|