[PATCH 1/2] ima: don't access a file's integrity status before an IMA policy is loaded

From: Mimi Zohar <zohar@linux.ibm.com>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Mimi Zohar <zohar@linux.ibm.com>,
	James Morris <jmorris@namei.org>,
	"Serge E . Hallyn" <serge@hallyn.com>,
	linux-integrity@vger.kernel.org,
	linux-security-module <linux-security-module@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Eric Biggers <ebiggers@kernel.org>,
	Kees Cook <keescook@chromium.org>
Subject: [PATCH 1/2] ima: don't access a file's integrity status before an IMA policy is loaded
Date: Mon, 22 Mar 2021 11:42:06 -0400	[thread overview]
Message-ID: <20210322154207.6802-1-zohar@linux.ibm.com> (raw)

Only after an IMA policy is loaded, check, save, or update the cached
file's integrity status.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
 security/integrity/ima/ima_main.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 9ef748ea829f..9d1196f712e1 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -606,6 +606,9 @@ void ima_post_create_tmpfile(struct user_namespace *mnt_userns,
 	struct integrity_iint_cache *iint;
 	int must_appraise;
 
+	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
+		return;
+
 	must_appraise = ima_must_appraise(mnt_userns, inode, MAY_ACCESS,
 					  FILE_CHECK);
 	if (!must_appraise)
@@ -636,6 +639,9 @@ void ima_post_path_mknod(struct user_namespace *mnt_userns,
 	struct inode *inode = dentry->d_inode;
 	int must_appraise;
 
+	if (!ima_policy_flag || !S_ISREG(inode->i_mode))
+		return;
+
 	must_appraise = ima_must_appraise(mnt_userns, inode, MAY_ACCESS,
 					  FILE_CHECK);
 	if (!must_appraise)
-- 
2.27.0

