Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754101AbaJASnx (ORCPT ); Wed, 1 Oct 2014 14:43:53 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:49505 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753898AbaJASnL (ORCPT ); Wed, 1 Oct 2014 14:43:11 -0400 From: Dmitry Kasatkin X-Google-Original-From: Dmitry Kasatkin To: zohar@linux.vnet.ibm.com, linux-ima-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Dmitry Kasatkin Subject: [PATCH v2 3/4] ima: check appraisal flag in the ima_file_free() hook Date: Wed, 1 Oct 2014 21:43:09 +0300 Message-Id: <600aeb6a5b8eca7eb381392e142ca71484717e9c.1412188590.git.d.kasatkin@samsung.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ima_file_free() hook is only used by appraisal module to update hash when file was modified. When there were no integrity checks on inode, S_IMA flag is not set, integrity_iint_find() returns NULL and it quits. When inode is only measured/audited but not appraised, iint is allocated and it will cause calling ima_check_last_writer() which unnecessarily locks i_mutex. Currently ima_file_free() checks 'iint_initialized'. But it looks that it is a mistake and originally 'ima_appraise' had to be used instead. In fact usage of 'iint_initialized' is completely unnecessary because S_IMA flag would not be set if iint was not allocated. This patch uses lately introduced ima_policy_flag to test if appraisal was enabled by policy. With this change 'iint_initialized' is no longer used anywhere. Indeed, integrity cache is allocated with SLAB_PANIC and kernel will panic if allocation fails during kernel initialization. So this variable is unnecessary and thus this patch removes it. Changes in v2: * 'iint_initialized' removal patch merged to this patch (requested by Mimi) Signed-off-by: Dmitry Kasatkin --- security/integrity/iint.c | 3 --- security/integrity/ima/ima_main.c | 2 +- security/integrity/integrity.h | 3 --- 3 files changed, 1 insertion(+), 7 deletions(-) diff --git a/security/integrity/iint.c b/security/integrity/iint.c index a521edf..cc3eb4d 100644 --- a/security/integrity/iint.c +++ b/security/integrity/iint.c @@ -25,8 +25,6 @@ static struct rb_root integrity_iint_tree = RB_ROOT; static DEFINE_RWLOCK(integrity_iint_lock); static struct kmem_cache *iint_cache __read_mostly; -int iint_initialized; - /* * __integrity_iint_find - return the iint associated with an inode */ @@ -166,7 +164,6 @@ static int __init integrity_iintcache_init(void) iint_cache = kmem_cache_create("iint_cache", sizeof(struct integrity_iint_cache), 0, SLAB_PANIC, init_once); - iint_initialized = 1; return 0; } security_initcall(integrity_iintcache_init); diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 62f59ec..87d7df7 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -143,7 +143,7 @@ void ima_file_free(struct file *file) struct inode *inode = file_inode(file); struct integrity_iint_cache *iint; - if (!iint_initialized || !S_ISREG(inode->i_mode)) + if (!(ima_policy_flag & IMA_APPRAISE) || !S_ISREG(inode->i_mode)) return; iint = integrity_iint_find(inode); diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index aafb468..f51ad65 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -169,6 +169,3 @@ static inline void integrity_audit_msg(int audit_msgno, struct inode *inode, { } #endif - -/* set during initialization */ -extern int iint_initialized; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/