diff options
| -rw-r--r-- | fs/namei.c | 171 |
1 files changed, 103 insertions, 68 deletions
diff --git a/fs/namei.c b/fs/namei.c index 60b74b3946a1..3c39fa1608c5 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1645,6 +1645,104 @@ exit: return ERR_PTR(error); } +static struct file *do_last(struct nameidata *nd, struct path *path, + int open_flag, int flag, int acc_mode, + int mode, const char *pathname, + struct dentry *dir, int *is_link) +{ + struct file *filp; + int error; + + *is_link = 0; + + error = PTR_ERR(path->dentry); + if (IS_ERR(path->dentry)) { + mutex_unlock(&dir->d_inode->i_mutex); + goto exit; + } + + if (IS_ERR(nd->intent.open.file)) { + error = PTR_ERR(nd->intent.open.file); + goto exit_mutex_unlock; + } + + /* Negative dentry, just create the file */ + if (!path->dentry->d_inode) { + /* + * This write is needed to ensure that a + * ro->rw transition does not occur between + * the time when the file is created and when + * a permanent write count is taken through + * the 'struct file' in nameidata_to_filp(). + */ + error = mnt_want_write(nd->path.mnt); + if (error) + goto exit_mutex_unlock; + error = __open_namei_create(nd, path, open_flag, mode); + if (error) { + mnt_drop_write(nd->path.mnt); + goto exit; + } + filp = nameidata_to_filp(nd); + mnt_drop_write(nd->path.mnt); + if (nd->root.mnt) + path_put(&nd->root); + if (!IS_ERR(filp)) { + error = ima_file_check(filp, acc_mode); + if (error) { + fput(filp); + filp = ERR_PTR(error); + } + } + return filp; + } + + /* + * It already exists. + */ + mutex_unlock(&dir->d_inode->i_mutex); + audit_inode(pathname, path->dentry); + + error = -EEXIST; + if (flag & O_EXCL) + goto exit_dput; + + if (__follow_mount(path)) { + error = -ELOOP; + if (flag & O_NOFOLLOW) + goto exit_dput; + } + + error = -ENOENT; + if (!path->dentry->d_inode) + goto exit_dput; + if (path->dentry->d_inode->i_op->follow_link) { + *is_link = 1; + return NULL; + } + + path_to_nameidata(path, nd); + error = -EISDIR; + if (S_ISDIR(path->dentry->d_inode->i_mode)) + goto exit; + filp = finish_open(nd, open_flag, flag, acc_mode); + if (nd->root.mnt) + path_put(&nd->root); + return filp; + +exit_mutex_unlock: + mutex_unlock(&dir->d_inode->i_mutex); +exit_dput: + path_put_conditional(path, nd); +exit: + if (!IS_ERR(nd->intent.open.file)) + release_open_intent(nd); + if (nd->root.mnt) + path_put(&nd->root); + path_put(&nd->path); + return ERR_PTR(error); +} + /* * Note that the low bits of the passed in "open_flag" * are not the same as in the local variable "flag". See @@ -1661,6 +1759,7 @@ 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 is_link; /* * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only @@ -1754,82 +1853,18 @@ reval: path.mnt = nd.path.mnt; do_last: - error = PTR_ERR(path.dentry); - if (IS_ERR(path.dentry)) { - mutex_unlock(&dir->d_inode->i_mutex); - goto exit; - } - - if (IS_ERR(nd.intent.open.file)) { - error = PTR_ERR(nd.intent.open.file); - goto exit_mutex_unlock; - } - - /* Negative dentry, just create the file */ - if (!path.dentry->d_inode) { - /* - * This write is needed to ensure that a - * ro->rw transition does not occur between - * the time when the file is created and when - * a permanent write count is taken through - * the 'struct file' in nameidata_to_filp(). - */ - error = mnt_want_write(nd.path.mnt); - if (error) - goto exit_mutex_unlock; - error = __open_namei_create(&nd, &path, open_flag, mode); - if (error) { - mnt_drop_write(nd.path.mnt); - goto exit; - } - filp = nameidata_to_filp(&nd); - mnt_drop_write(nd.path.mnt); - if (nd.root.mnt) - path_put(&nd.root); - if (!IS_ERR(filp)) { - error = ima_file_check(filp, acc_mode); - if (error) { - fput(filp); - filp = ERR_PTR(error); - } - } - return filp; - } - - /* - * It already exists. - */ - mutex_unlock(&dir->d_inode->i_mutex); - audit_inode(pathname, path.dentry); - - error = -EEXIST; - if (flag & O_EXCL) - goto exit_dput; - - if (__follow_mount(&path)) { - error = -ELOOP; - if (flag & O_NOFOLLOW) - goto exit_dput; - } - - error = -ENOENT; - if (!path.dentry->d_inode) - goto exit_dput; - if (path.dentry->d_inode->i_op->follow_link) + filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode, + pathname, dir, &is_link); + if (is_link) goto do_link; + return filp; - path_to_nameidata(&path, &nd); - error = -EISDIR; - if (S_ISDIR(path.dentry->d_inode->i_mode)) - goto exit; ok: filp = finish_open(&nd, open_flag, flag, acc_mode); if (nd.root.mnt) path_put(&nd.root); return filp; -exit_mutex_unlock: - mutex_unlock(&dir->d_inode->i_mutex); exit_dput: path_put_conditional(&path, &nd); exit: |