From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,INCLUDES_PULL_REQUEST, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2DA0BC35280 for ; Thu, 7 May 2020 23:45:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE292208E4 for ; Thu, 7 May 2020 23:45:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726480AbgEGXpR (ORCPT ); Thu, 7 May 2020 19:45:17 -0400 Received: from namei.org ([65.99.196.166]:57630 "EHLO namei.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726476AbgEGXpR (ORCPT ); Thu, 7 May 2020 19:45:17 -0400 Received: from localhost (localhost [127.0.0.1]) by namei.org (8.14.4/8.14.4) with ESMTP id 047NjBCx016267; Thu, 7 May 2020 23:45:11 GMT Date: Fri, 8 May 2020 09:45:11 +1000 (AEST) From: James Morris To: Linus Torvalds cc: linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, KP Singh Subject: [GIT PULL] security: Fix the default value of fs_context_parse_param hook Message-ID: User-Agent: Alpine 2.21 (LRH 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Please pull this fix from KP Singh (several folks are reporting issues around this): The following changes since commit c45e8bccecaf633480d378daff11e122dfd5e96d: Merge tag 'for-5.7/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm (2020-04-30 16:45:08 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security.git for-v5.7 for you to fetch changes up to 54261af473be4c5481f6196064445d2945f2bdab: security: Fix the default value of fs_context_parse_param hook (2020-04-30 20:29:34 -0700) ---------------------------------------------------------------- KP Singh (1): security: Fix the default value of fs_context_parse_param hook include/linux/lsm_hook_defs.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- commit 54261af473be4c5481f6196064445d2945f2bdab Author: KP Singh Date: Thu Apr 30 17:52:40 2020 +0200 security: Fix the default value of fs_context_parse_param hook security_fs_context_parse_param is called by vfs_parse_fs_param and a succussful return value (i.e 0) implies that a parameter will be consumed by the LSM framework. This stops all further parsing of the parmeter by VFS. Furthermore, if an LSM hook returns a success, the remaining LSM hooks are not invoked for the parameter. The current default behavior of returning success means that all the parameters are expected to be parsed by the LSM hook and none of them end up being populated by vfs in fs_context This was noticed when lsm=bpf is supplied on the command line before any other LSM. As the bpf lsm uses this default value to implement a default hook, this resulted in a failure to parse any fs_context parameters and a failure to mount the root filesystem. Fixes: 98e828a0650f ("security: Refactor declaration of LSM hooks") Reported-by: Mikko Ylinen Signed-off-by: KP Singh Signed-off-by: James Morris diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 9cd4455528e5..1bdd027766d4 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -55,7 +55,7 @@ LSM_HOOK(void, LSM_RET_VOID, bprm_committing_creds, struct linux_binprm *bprm) LSM_HOOK(void, LSM_RET_VOID, bprm_committed_creds, struct linux_binprm *bprm) LSM_HOOK(int, 0, fs_context_dup, struct fs_context *fc, struct fs_context *src_sc) -LSM_HOOK(int, 0, fs_context_parse_param, struct fs_context *fc, +LSM_HOOK(int, -ENOPARAM, fs_context_parse_param, struct fs_context *fc, struct fs_parameter *param) LSM_HOOK(int, 0, sb_alloc_security, struct super_block *sb) LSM_HOOK(void, LSM_RET_VOID, sb_free_security, struct super_block *sb)