[PATCH 1/2] ipe: fix use-after-free when auditing a newly loaded policy

[Fan Wu]

new_policy() audits the policy after ipe_new_policyfs_node() publishes it
and drops the new directory's inode lock. A concurrent delete can free
the policy while ipe_audit_policy_load() is still using it.

Audit the successful load under that lock.

Fixes: f44554b5067b ("audit,ipe: add IPE auditing support")
Cc: stable at vger.kernel.org
Assisted-by: claude-opus-5.5
Signed-off-by: Fan Wu <wufan at kernel.org>
---
 security/ipe/fs.c        | 8 +++-----
 security/ipe/policy_fs.c | 3 +++
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/security/ipe/fs.c b/security/ipe/fs.c
index 076c111c85c8..847a76afb93d 100644
--- a/security/ipe/fs.c
+++ b/security/ipe/fs.c
@@ -159,18 +159,16 @@ static ssize_t new_policy(struct file *f, const char __user *data,
 	}
 
 	rc = ipe_new_policyfs_node(p);
-	if (rc)
-		goto out;
 
 out:
 	kfree(copy);
 	if (rc < 0) {
 		ipe_free_policy(p);
 		ipe_audit_policy_load(ERR_PTR(rc));
-	} else {
-		ipe_audit_policy_load(p);
+		return rc;
 	}
-	return (rc < 0) ? rc : len;
+
+	return len;
 }
 
 static const struct file_operations np_fops = {
diff --git a/security/ipe/policy_fs.c b/security/ipe/policy_fs.c
index 9d92d8a14b13..a7aeb57483c6 100644
--- a/security/ipe/policy_fs.c
+++ b/security/ipe/policy_fs.c
@@ -481,6 +481,9 @@ int ipe_new_policyfs_node(struct ipe_policy *p)
 	inode_lock(root);
 	p->policyfs = policyfs;
 	root->i_private = p;
+	/* Only audit signed policies from userspace */
+	if (p->pkcs7)
+		ipe_audit_policy_load(p);
 	inode_unlock(root);
 
 	return 0;
-- 
2.55.0