From 1f36f774b22a0ceb7dd33eca626746c81a97b6a5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 26 Dec 2009 10:56:19 -0500 Subject: [PATCH] Switch !O_CREAT case to use of do_last() ... and now we have all intents crap well localized Signed-off-by: Al Viro --- fs/namei.c | 127 ++++++++++++++++++++++++++++------------------------- 1 file changed, 66 insertions(+), 61 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 1f5d86d1fbf5..9a6456099f1e 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1359,22 +1359,6 @@ static inline int may_create(struct inode *dir, struct dentry *child) return inode_permission(dir, MAY_WRITE | MAY_EXEC); } -/* - * O_DIRECTORY translates into forcing a directory lookup. - */ -static inline int lookup_flags(unsigned int f) -{ - unsigned long retval = LOOKUP_FOLLOW; - - if (f & O_NOFOLLOW) - retval &= ~LOOKUP_FOLLOW; - - if (f & O_DIRECTORY) - retval |= LOOKUP_DIRECTORY; - - return retval; -} - /* * p1 and p2 should be directories on the same fs. */ @@ -1631,19 +1615,60 @@ exit: static struct file *do_last(struct nameidata *nd, struct path *path, int open_flag, int acc_mode, - int mode, const char *pathname) + int mode, const char *pathname, + int *want_dir) { struct dentry *dir = nd->path.dentry; struct file *filp; - int error; + int error = -EISDIR; - if (nd->last_type == LAST_BIND) + switch (nd->last_type) { + case LAST_DOTDOT: + follow_dotdot(nd); + dir = nd->path.dentry; + if (nd->path.mnt->mnt_sb->s_type->fs_flags & FS_REVAL_DOT) { + if (!dir->d_op->d_revalidate(dir, nd)) { + error = -ESTALE; + goto exit; + } + } + /* fallthrough */ + case LAST_DOT: + case LAST_ROOT: + if (open_flag & O_CREAT) + goto exit; + /* fallthrough */ + case LAST_BIND: + audit_inode(pathname, dir); goto ok; + } - error = -EISDIR; - if (nd->last_type != LAST_NORM || nd->last.name[nd->last.len]) - goto exit; + /* trailing slashes? */ + if (nd->last.name[nd->last.len]) { + if (open_flag & O_CREAT) + goto exit; + *want_dir = 1; + } + /* just plain open? */ + if (!(open_flag & O_CREAT)) { + error = do_lookup(nd, &nd->last, path); + if (error) + goto exit; + error = -ENOENT; + if (!path->dentry->d_inode) + goto exit_dput; + if (path->dentry->d_inode->i_op->follow_link) + return NULL; + error = -ENOTDIR; + if (*want_dir & !path->dentry->d_inode->i_op->lookup) + goto exit_dput; + path_to_nameidata(path, nd); + audit_inode(pathname, nd->path.dentry); + goto ok; + } + + /* OK, it's O_CREAT */ mutex_lock(&dir->d_inode->i_mutex); path->dentry = lookup_hash(nd); @@ -1746,6 +1771,10 @@ struct file *do_filp_open(int dfd, const char *pathname, int count = 0; int flag = open_to_namei_flags(open_flag); int force_reval = 0; + int want_dir = open_flag & O_DIRECTORY; + + if (!(open_flag & O_CREAT)) + mode = 0; /* * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only @@ -1768,35 +1797,7 @@ struct file *do_filp_open(int dfd, const char *pathname, if (open_flag & O_APPEND) acc_mode |= MAY_APPEND; - /* - * The simplest case - just a plain lookup. - */ - if (!(open_flag & O_CREAT)) { - filp = get_empty_filp(); - - if (filp == NULL) - return ERR_PTR(-ENFILE); - nd.intent.open.file = filp; - filp->f_flags = open_flag; - nd.intent.open.flags = flag; - nd.intent.open.create_mode = 0; - error = do_path_lookup(dfd, pathname, - lookup_flags(open_flag)|LOOKUP_OPEN, &nd); - if (IS_ERR(nd.intent.open.file)) { - if (error == 0) { - error = PTR_ERR(nd.intent.open.file); - path_put(&nd.path); - } - } else if (error) - release_open_intent(&nd); - if (error) - return ERR_PTR(error); - return finish_open(&nd, open_flag, acc_mode); - } - - /* - * Create - we need to know the parent. - */ + /* find the parent */ reval: error = path_init(dfd, pathname, LOOKUP_PARENT, &nd); if (error) @@ -1810,7 +1811,7 @@ reval: filp = ERR_PTR(error); goto out; } - if (unlikely(!audit_dummy_context())) + if (unlikely(!audit_dummy_context()) && (open_flag & O_CREAT)) audit_inode(pathname, nd.path.dentry); /* @@ -1826,16 +1827,22 @@ reval: nd.intent.open.flags = flag; nd.intent.open.create_mode = mode; nd.flags &= ~LOOKUP_PARENT; - nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN; - if (open_flag & O_EXCL) - nd.flags |= LOOKUP_EXCL; - filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname); + nd.flags |= LOOKUP_OPEN; + if (open_flag & O_CREAT) { + nd.flags |= LOOKUP_CREATE; + if (open_flag & O_EXCL) + nd.flags |= LOOKUP_EXCL; + } + filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname, &want_dir); while (unlikely(!filp)) { /* trailing symlink */ struct path holder; - struct inode *inode; + struct inode *inode = path.dentry->d_inode; void *cookie; error = -ELOOP; - if ((open_flag & O_NOFOLLOW) || count++ == 32) + /* S_ISDIR part is a temporary automount kludge */ + if ((open_flag & O_NOFOLLOW) && !S_ISDIR(inode->i_mode)) + goto exit_dput; + if (count++ == 32) goto exit_dput; /* * This is subtle. Instead of calling do_follow_link() we do @@ -1855,7 +1862,6 @@ reval: error = __do_follow_link(&path, &nd, &cookie); if (unlikely(error)) { /* nd.path had been dropped */ - inode = path.dentry->d_inode; if (!IS_ERR(cookie) && inode->i_op->put_link) inode->i_op->put_link(path.dentry, &nd, cookie); path_put(&path); @@ -1865,8 +1871,7 @@ reval: } holder = path; nd.flags &= ~LOOKUP_PARENT; - filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname); - inode = holder.dentry->d_inode; + filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname, &want_dir); if (inode->i_op->put_link) inode->i_op->put_link(holder.dentry, &nd, cookie); path_put(&holder); -- 2.20.1