[RFC PATCH 1/3] lsm: cleanup the size counters in security_getselfattr()

From: Paul Moore <paul@paul-moore.com>
To: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org,
	"Casey Schaufler" <casey@schaufler-ca.com>,
	"John Johansen" <john.johansen@canonical.com>,
	"Mickaël Salaün" <mic@digikod.net>
Subject: [RFC PATCH 1/3] lsm: cleanup the size counters in security_getselfattr()
Date: Tue, 24 Oct 2023 17:35:27 -0400	[thread overview]
Message-ID: <20231024213525.361332-5-paul@paul-moore.com> (raw)
In-Reply-To: <20231024213525.361332-4-paul@paul-moore.com>

Zero out all of the size counters in the -E2BIG case (buffer too
small) to help make the current code a bit more robust in the face of
future code changes.

Signed-off-by: Paul Moore <paul@paul-moore.com>
---
 security/security.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/security/security.c b/security/security.c
index 988483fcf153..9c63acded4ee 100644
--- a/security/security.c
+++ b/security/security.c
@@ -3951,8 +3951,9 @@ int security_getselfattr(unsigned int attr, struct lsm_ctx __user *uctx,
 			continue;
 		}
 		if (rc == -E2BIG) {
-			toobig = true;
+			rc = 0;
 			left = 0;
+			toobig = true;
 		} else if (rc < 0)
 			return rc;
 		else
-- 
2.42.0

