Hello. Chris Wright wrote: > * Toshiharu Harada (haradats@xxxxxxxxxxxxx) wrote: > > This patch allows LSM to check permission using "struct vfsmount" > > without passing "struct vfsmount" to VFS helper functions. > > This is simply duplicating many of the existing checks. > I don't see how this is an improvement. > > > --- mm.orig/fs/namei.c > > +++ mm/fs/namei.c > > @@ -1595,6 +1595,9 @@ int vfs_create(struct inode *dir, struct > > error = security_inode_create(dir, dentry, mode); > > if (error) > > return error; > > + error = security_path_create(dir, dentry, mode, nd); > > + if (error) > > + return error; > > Pure duplication (of course adding nameidata, although I think you just > want path). Right. I should have added "path" parameter rather than adding a new hook. But to avoid touching vfs_*(), I moved security_path_create() to the callers of vfs_create(). > > DQUOT_INIT(dir); > > error = dir->i_op->create(dir, dentry, mode, nd); > > if (!error) > > @@ -1650,6 +1653,17 @@ int may_open(struct nameidata *nd, int a > ... > error = vfs_permission(nd, acc_mode); > if (error) > return error; > ... > > return -EPERM; > > > > /* > > + * security_inode_permission() called from vfs_permission() > > + * can't know that the file is going to be truncated when > > + * open(filename, O_WRONLY | O_TRUNC | O_APPEND) is used. > > + * So, this hook checks O_APPEND and O_TRUNC flags as well > > + * as MAY_READ and MAY_WRITE flags. > > + */ > > + error = security_path_open(nd->path.dentry, nd->path.mnt, flag); > > + if (error) > > + return error; > > Also duplication. And why the unique flag handling, you don't seem to > ever check? Sorry. I didn't know security_dentry_open() is available. Now, security_path_open() and security_path_uselib() have gone away. But it also turned out that security_dentry_open() is too late for checking open(O_CREAT) and open(O_TRUNC) cases. Thus, somehow, I want to check O_CREAT before entering vfs_create() and check O_TRUNC before entering do_truncate() from may_open(). Regards. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
