diff options
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 80 |
1 files changed, 52 insertions, 28 deletions
diff --git a/fs/namei.c b/fs/namei.c index 8ee7785d564..abc8d2df121 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1487,11 +1487,13 @@ static int path_init(int dfd, const char *name, unsigned int flags, nd->depth = 0; if (flags & LOOKUP_ROOT) { struct inode *inode = nd->root.dentry->d_inode; - if (!inode->i_op->lookup) - return -ENOTDIR; - retval = inode_permission(inode, MAY_EXEC); - if (retval) - return retval; + if (*name) { + if (!inode->i_op->lookup) + return -ENOTDIR; + retval = inode_permission(inode, MAY_EXEC); + if (retval) + return retval; + } nd->path = nd->root; nd->inode = inode; if (flags & LOOKUP_RCU) { @@ -1937,7 +1939,7 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, return error; } -int may_open(struct path *path, int acc_mode, int flag) +static int may_open(struct path *path, int acc_mode, int flag) { struct dentry *dentry = path->dentry; struct inode *inode = dentry->d_inode; @@ -2250,11 +2252,10 @@ exit: } static struct file *path_openat(int dfd, const char *pathname, - const struct open_flags *op, int flags) + struct nameidata *nd, const struct open_flags *op, int flags) { struct file *base = NULL; struct file *filp; - struct nameidata nd; struct path path; int count = 0; int error; @@ -2264,27 +2265,27 @@ static struct file *path_openat(int dfd, const char *pathname, return ERR_PTR(-ENFILE); filp->f_flags = op->open_flag; - nd.intent.open.file = filp; - nd.intent.open.flags = open_to_namei_flags(op->open_flag); - nd.intent.open.create_mode = op->mode; + nd->intent.open.file = filp; + nd->intent.open.flags = open_to_namei_flags(op->open_flag); + nd->intent.open.create_mode = op->mode; - error = path_init(dfd, pathname, flags | LOOKUP_PARENT, &nd, &base); + error = path_init(dfd, pathname, flags | LOOKUP_PARENT, nd, &base); if (unlikely(error)) goto out_filp; current->total_link_count = 0; - error = link_path_walk(pathname, &nd); + error = link_path_walk(pathname, nd); if (unlikely(error)) goto out_filp; - filp = do_last(&nd, &path, op, pathname); + filp = do_last(nd, &path, op, pathname); while (unlikely(!filp)) { /* trailing symlink */ struct path link = path; struct inode *linki = link.dentry->d_inode; void *cookie; - if (!(nd.flags & LOOKUP_FOLLOW) || count++ == 32) { - path_put_conditional(&path, &nd); - path_put(&nd.path); + if (!(nd->flags & LOOKUP_FOLLOW) || count++ == 32) { + path_put_conditional(&path, nd); + path_put(&nd->path); filp = ERR_PTR(-ELOOP); break; } @@ -2299,23 +2300,23 @@ static struct file *path_openat(int dfd, const char *pathname, * have to putname() it when we are done. Procfs-like symlinks * just set LAST_BIND. */ - nd.flags |= LOOKUP_PARENT; - nd.flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL); - error = __do_follow_link(&link, &nd, &cookie); + nd->flags |= LOOKUP_PARENT; + nd->flags &= ~(LOOKUP_OPEN|LOOKUP_CREATE|LOOKUP_EXCL); + error = __do_follow_link(&link, nd, &cookie); if (unlikely(error)) filp = ERR_PTR(error); else - filp = do_last(&nd, &path, op, pathname); + filp = do_last(nd, &path, op, pathname); if (!IS_ERR(cookie) && linki->i_op->put_link) - linki->i_op->put_link(link.dentry, &nd, cookie); + linki->i_op->put_link(link.dentry, nd, cookie); path_put(&link); } out: - if (nd.root.mnt && !(nd.flags & LOOKUP_ROOT)) - path_put(&nd.root); + if (nd->root.mnt && !(nd->flags & LOOKUP_ROOT)) + path_put(&nd->root); if (base) fput(base); - release_open_intent(&nd); + release_open_intent(nd); return filp; out_filp: @@ -2326,16 +2327,39 @@ out_filp: struct file *do_filp_open(int dfd, const char *pathname, const struct open_flags *op, int flags) { + struct nameidata nd; struct file *filp; - filp = path_openat(dfd, pathname, op, flags | LOOKUP_RCU); + filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_RCU); if (unlikely(filp == ERR_PTR(-ECHILD))) - filp = path_openat(dfd, pathname, op, flags); + filp = path_openat(dfd, pathname, &nd, op, flags); if (unlikely(filp == ERR_PTR(-ESTALE))) - filp = path_openat(dfd, pathname, op, flags | LOOKUP_REVAL); + filp = path_openat(dfd, pathname, &nd, op, flags | LOOKUP_REVAL); return filp; } +struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, + const char *name, const struct open_flags *op, int flags) +{ + struct nameidata nd; + struct file *file; + + nd.root.mnt = mnt; + nd.root.dentry = dentry; + + flags |= LOOKUP_ROOT; + + if (dentry->d_inode->i_op->follow_link) + return ERR_PTR(-ELOOP); + + file = path_openat(-1, name, &nd, op, flags | LOOKUP_RCU); + if (unlikely(file == ERR_PTR(-ECHILD))) + file = path_openat(-1, name, &nd, op, flags); + if (unlikely(file == ERR_PTR(-ESTALE))) + file = path_openat(-1, name, &nd, op, flags | LOOKUP_REVAL); + return file; +} + /** * lookup_create - lookup a dentry, creating it if it doesn't exist * @nd: nameidata info |