diff options
| -rw-r--r-- | fs/autofs/dev-ioctl.c | 6 | ||||
| -rw-r--r-- | fs/internal.h | 1 | ||||
| -rw-r--r-- | fs/namei.c | 89 | ||||
| -rw-r--r-- | fs/namespace.c | 4 | ||||
| -rw-r--r-- | include/linux/namei.h | 2 |
5 files changed, 12 insertions, 90 deletions
diff --git a/fs/autofs/dev-ioctl.c b/fs/autofs/dev-ioctl.c index a3cdb0036c5d..f3a0f412b43b 100644 --- a/fs/autofs/dev-ioctl.c +++ b/fs/autofs/dev-ioctl.c @@ -186,7 +186,7 @@ static int find_autofs_mount(const char *pathname, struct path path; int err; - err = kern_path_mountpoint(AT_FDCWD, pathname, &path, 0); + err = kern_path(pathname, LOOKUP_MOUNTPOINT, &path); if (err) return err; err = -ENOENT; @@ -519,8 +519,8 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp, if (!fp || param->ioctlfd == -1) { if (autofs_type_any(type)) - err = kern_path_mountpoint(AT_FDCWD, - name, &path, LOOKUP_FOLLOW); + err = kern_path(name, LOOKUP_FOLLOW | LOOKUP_MOUNTPOINT, + &path); else err = find_autofs_mount(name, &path, test_by_type, &type); diff --git a/fs/internal.h b/fs/internal.h index f3f280b952a3..b108a8eb75ca 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -61,7 +61,6 @@ extern int finish_clean_context(struct fs_context *fc); */ extern int filename_lookup(int dfd, struct filename *name, unsigned flags, struct path *path, struct path *root); -extern int user_path_mountpoint_at(int, const char __user *, unsigned int, struct path *); extern int vfs_path_lookup(struct dentry *, struct vfsmount *, const char *, unsigned int, struct path *); long do_mknodat(int dfd, const char __user *filename, umode_t mode, diff --git a/fs/namei.c b/fs/namei.c index 8a673f44ffc2..0fcd738b95b9 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2382,6 +2382,10 @@ static int path_lookupat(struct nameidata *nd, unsigned flags, struct path *path if (!err && nd->flags & LOOKUP_DIRECTORY) if (!d_can_lookup(nd->path.dentry)) err = -ENOTDIR; + if (!err && unlikely(nd->flags & LOOKUP_MOUNTPOINT)) { + err = handle_lookup_down(nd); + nd->flags &= ~LOOKUP_JUMPED; // no d_weak_revalidate(), please... + } if (!err) { *path = nd->path; nd->path.mnt = NULL; @@ -2410,7 +2414,8 @@ int filename_lookup(int dfd, struct filename *name, unsigned flags, retval = path_lookupat(&nd, flags | LOOKUP_REVAL, path); if (likely(!retval)) - audit_inode(name, path->dentry, 0); + audit_inode(name, path->dentry, + flags & LOOKUP_MOUNTPOINT ? AUDIT_INODE_NOEVAL : 0); restore_nameidata(); putname(name); return retval; @@ -2688,88 +2693,6 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags, } EXPORT_SYMBOL(user_path_at_empty); -/** - * path_mountpoint - look up a path to be umounted - * @nd: lookup context - * @flags: lookup flags - * @path: pointer to container for result - * - * Look up the given name, but don't attempt to revalidate the last component. - * Returns 0 and "path" will be valid on success; Returns error otherwise. - */ -static int -path_mountpoint(struct nameidata *nd, unsigned flags, struct path *path) -{ - const char *s = path_init(nd, flags); - int err; - - while (!(err = link_path_walk(s, nd)) && - (err = lookup_last(nd)) > 0) { - s = trailing_symlink(nd); - } - if (!err && (nd->flags & LOOKUP_RCU)) - err = unlazy_walk(nd); - if (!err) - err = handle_lookup_down(nd); - if (!err) { - *path = nd->path; - nd->path.mnt = NULL; - nd->path.dentry = NULL; - } - terminate_walk(nd); - return err; -} - -static int -filename_mountpoint(int dfd, struct filename *name, struct path *path, - unsigned int flags) -{ - struct nameidata nd; - int error; - if (IS_ERR(name)) - return PTR_ERR(name); - set_nameidata(&nd, dfd, name); - error = path_mountpoint(&nd, flags | LOOKUP_RCU, path); - if (unlikely(error == -ECHILD)) - error = path_mountpoint(&nd, flags, path); - if (unlikely(error == -ESTALE)) - error = path_mountpoint(&nd, flags | LOOKUP_REVAL, path); - if (likely(!error)) - audit_inode(name, path->dentry, AUDIT_INODE_NOEVAL); - restore_nameidata(); - putname(name); - return error; -} - -/** - * user_path_mountpoint_at - lookup a path from userland in order to umount it - * @dfd: directory file descriptor - * @name: pathname from userland - * @flags: lookup flags - * @path: pointer to container to hold result - * - * A umount is a special case for path walking. We're not actually interested - * in the inode in this situation, and ESTALE errors can be a problem. We - * simply want track down the dentry and vfsmount attached at the mountpoint - * and avoid revalidating the last component. - * - * Returns 0 and populates "path" on success. - */ -int -user_path_mountpoint_at(int dfd, const char __user *name, unsigned int flags, - struct path *path) -{ - return filename_mountpoint(dfd, getname(name), path, flags); -} - -int -kern_path_mountpoint(int dfd, const char *name, struct path *path, - unsigned int flags) -{ - return filename_mountpoint(dfd, getname_kernel(name), path, flags); -} -EXPORT_SYMBOL(kern_path_mountpoint); - int __check_sticky(struct inode *dir, struct inode *inode) { kuid_t fsuid = current_fsuid(); diff --git a/fs/namespace.c b/fs/namespace.c index 743980380a8f..a28e4db075ed 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1669,7 +1669,7 @@ int ksys_umount(char __user *name, int flags) struct path path; struct mount *mnt; int retval; - int lookup_flags = 0; + int lookup_flags = LOOKUP_MOUNTPOINT; if (flags & ~(MNT_FORCE | MNT_DETACH | MNT_EXPIRE | UMOUNT_NOFOLLOW)) return -EINVAL; @@ -1680,7 +1680,7 @@ int ksys_umount(char __user *name, int flags) if (!(flags & UMOUNT_NOFOLLOW)) lookup_flags |= LOOKUP_FOLLOW; - retval = user_path_mountpoint_at(AT_FDCWD, name, lookup_flags, &path); + retval = user_path_at(AT_FDCWD, name, lookup_flags, &path); if (retval) goto out; mnt = real_mount(path.mnt); diff --git a/include/linux/namei.h b/include/linux/namei.h index 0dd980d7318f..d9576a051808 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -23,6 +23,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND}; #define LOOKUP_AUTOMOUNT 0x0004 /* force terminal automount */ #define LOOKUP_EMPTY 0x4000 /* accept empty path [user_... only] */ #define LOOKUP_DOWN 0x8000 /* follow mounts in the starting point */ +#define LOOKUP_MOUNTPOINT 0x0080 /* follow mounts in the end */ #define LOOKUP_REVAL 0x0020 /* tell ->d_revalidate() to trust no cache */ #define LOOKUP_RCU 0x0040 /* RCU pathwalk mode; semi-internal */ @@ -64,7 +65,6 @@ extern struct dentry *kern_path_create(int, const char *, struct path *, unsigne extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int); extern void done_path_create(struct path *, struct dentry *); extern struct dentry *kern_path_locked(const char *, struct path *); -extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int); extern struct dentry *try_lookup_one_len(const char *, struct dentry *, int); extern struct dentry *lookup_one_len(const char *, struct dentry *, int); |