[PATCH v3 4/6] ima: Mark concurrent accesses to the iint pointer in the inode security blob

[Roberto Sassu]

From: Roberto Sassu <roberto.sassu at huawei.com>

Use the READ_ONCE() and WRITE_ONCE() macros to mark concurrent read and
write accesses to the portion of the inode security blob containing the
iint pointer.

Writers are serialized by the iint lock.

Reviewed-by: Mimi Zohar <zohar at linux.ibm.com>
Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>
---
 security/integrity/ima/ima_iint.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/security/integrity/ima/ima_iint.c b/security/integrity/ima/ima_iint.c
index fca9db293c79..c763f431fbc1 100644
--- a/security/integrity/ima/ima_iint.c
+++ b/security/integrity/ima/ima_iint.c
@@ -32,7 +32,7 @@ struct ima_iint_cache *ima_iint_find(struct inode *inode)
 	if (!iint_lock)
 		return NULL;
 
-	return iint_lock->iint;
+	return READ_ONCE(iint_lock->iint);
 }
 
 #define IMA_MAX_NESTING (FILESYSTEM_MAX_STACK_DEPTH + 1)
@@ -99,7 +99,7 @@ struct ima_iint_cache *ima_inode_get(struct inode *inode)
 
 	lockdep_assert_held(&iint_lock->mutex);
 
-	iint = iint_lock->iint;
+	iint = READ_ONCE(iint_lock->iint);
 	if (iint)
 		return iint;
 
@@ -109,7 +109,7 @@ struct ima_iint_cache *ima_inode_get(struct inode *inode)
 
 	ima_iint_init_always(iint, inode);
 
-	iint_lock->iint = iint;
+	WRITE_ONCE(iint_lock->iint, iint);
 
 	return iint;
 }
-- 
2.34.1