diff options
| -rw-r--r-- | fs/namei.c | 84 |
1 files changed, 43 insertions, 41 deletions
diff --git a/fs/namei.c b/fs/namei.c index a9c593e4f35e..593cf3b01e74 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2146,7 +2146,8 @@ static int filename_lookup(int dfd, struct filename *name, unsigned flags, /* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ static int path_parentat(int dfd, const struct filename *name, - unsigned int flags, struct nameidata *nd) + unsigned int flags, struct nameidata *nd, + struct path *parent) { const char *s = path_init(dfd, name, flags, nd); int err; @@ -2155,26 +2156,34 @@ static int path_parentat(int dfd, const struct filename *name, err = link_path_walk(s, nd); if (!err) err = complete_walk(nd); - if (err) - terminate_walk(nd); + if (!err) { + *parent = nd->path; + nd->path.mnt = NULL; + nd->path.dentry = NULL; + } + terminate_walk(nd); path_cleanup(nd); return err; } static int filename_parentat(int dfd, struct filename *name, - unsigned int flags, struct nameidata *nd) + unsigned int flags, struct path *parent, + struct qstr *last, int *type) { int retval; - struct nameidata *saved_nd = set_nameidata(nd); + struct nameidata nd, *saved_nd = set_nameidata(&nd); - retval = path_parentat(dfd, name, flags | LOOKUP_RCU, nd); + retval = path_parentat(dfd, name, flags | LOOKUP_RCU, &nd, parent); if (unlikely(retval == -ECHILD)) - retval = path_parentat(dfd, name, flags, nd); + retval = path_parentat(dfd, name, flags, &nd, parent); if (unlikely(retval == -ESTALE)) - retval = path_parentat(dfd, name, flags | LOOKUP_REVAL, nd); - - if (likely(!retval)) - audit_inode(name, nd->path.dentry, LOOKUP_PARENT); + retval = path_parentat(dfd, name, flags | LOOKUP_REVAL, + &nd, parent); + if (likely(!retval)) { + *last = nd.last; + *type = nd.last_type; + audit_inode(name, parent->dentry, LOOKUP_PARENT); + } restore_nameidata(saved_nd); return retval; } @@ -2183,31 +2192,30 @@ static int filename_parentat(int dfd, struct filename *name, struct dentry *kern_path_locked(const char *name, struct path *path) { struct filename *filename = getname_kernel(name); - struct nameidata nd; + struct qstr last; + int type; struct dentry *d; int err; if (IS_ERR(filename)) return ERR_CAST(filename); - err = filename_parentat(AT_FDCWD, filename, 0, &nd); + err = filename_parentat(AT_FDCWD, filename, 0, path, &last, &type); if (err) { d = ERR_PTR(err); goto out; } - if (nd.last_type != LAST_NORM) { - path_put(&nd.path); + if (type != LAST_NORM) { + path_put(path); d = ERR_PTR(-EINVAL); goto out; } - mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); - d = __lookup_hash(&nd.last, nd.path.dentry, 0); + mutex_lock_nested(&path->dentry->d_inode->i_mutex, I_MUTEX_PARENT); + d = __lookup_hash(&last, path->dentry, 0); if (IS_ERR(d)) { - mutex_unlock(&nd.path.dentry->d_inode->i_mutex); - path_put(&nd.path); - goto out; + mutex_unlock(&path->dentry->d_inode->i_mutex); + path_put(path); } - *path = nd.path; out: putname(filename); return d; @@ -2317,7 +2325,6 @@ user_path_parent(int dfd, const char __user *path, int *type, unsigned int flags) { - struct nameidata nd; struct filename *s = getname(path); int error; @@ -2327,15 +2334,11 @@ user_path_parent(int dfd, const char __user *path, if (IS_ERR(s)) return s; - error = filename_parentat(dfd, s, flags, &nd); + error = filename_parentat(dfd, s, flags, parent, last, type); if (error) { putname(s); - return ERR_PTR(error); + s = ERR_PTR(error); } - *parent = nd.path; - *last = nd.last; - *type = nd.last_type; - return s; } @@ -3394,7 +3397,8 @@ static struct dentry *filename_create(int dfd, struct filename *name, struct path *path, unsigned int lookup_flags) { struct dentry *dentry = ERR_PTR(-EEXIST); - struct nameidata nd; + struct qstr last; + int type; int err2; int error; bool is_dir = (lookup_flags & LOOKUP_DIRECTORY); @@ -3405,7 +3409,7 @@ static struct dentry *filename_create(int dfd, struct filename *name, */ lookup_flags &= LOOKUP_REVAL; - error = filename_parentat(dfd, name, lookup_flags, &nd); + error = filename_parentat(dfd, name, lookup_flags, path, &last, &type); if (error) return ERR_PTR(error); @@ -3413,18 +3417,17 @@ static struct dentry *filename_create(int dfd, struct filename *name, * Yucky last component or no last component at all? * (foo/., foo/.., /////) */ - if (nd.last_type != LAST_NORM) + if (type != LAST_NORM) goto out; - nd.flags &= ~LOOKUP_PARENT; - nd.flags |= LOOKUP_CREATE | LOOKUP_EXCL; /* don't fail immediately if it's r/o, at least try to report other errors */ - err2 = mnt_want_write(nd.path.mnt); + err2 = mnt_want_write(path->mnt); /* * Do the final lookup. */ - mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); - dentry = __lookup_hash(&nd.last, nd.path.dentry, nd.flags); + lookup_flags |= LOOKUP_CREATE | LOOKUP_EXCL; + mutex_lock_nested(&path->dentry->d_inode->i_mutex, I_MUTEX_PARENT); + dentry = __lookup_hash(&last, path->dentry, lookup_flags); if (IS_ERR(dentry)) goto unlock; @@ -3438,7 +3441,7 @@ static struct dentry *filename_create(int dfd, struct filename *name, * all is fine. Let's be bastards - you had / on the end, you've * been asking for (non-existent) directory. -ENOENT for you. */ - if (unlikely(!is_dir && nd.last.name[nd.last.len])) { + if (unlikely(!is_dir && last.name[last.len])) { error = -ENOENT; goto fail; } @@ -3446,17 +3449,16 @@ static struct dentry *filename_create(int dfd, struct filename *name, error = err2; goto fail; } - *path = nd.path; return dentry; fail: dput(dentry); dentry = ERR_PTR(error); unlock: - mutex_unlock(&nd.path.dentry->d_inode->i_mutex); + mutex_unlock(&path->dentry->d_inode->i_mutex); if (!err2) - mnt_drop_write(nd.path.mnt); + mnt_drop_write(path->mnt); out: - path_put(&nd.path); + path_put(path); return dentry; } |