From: Arnd Bergmann <arnd@arndb.de>
To: John Johansen <john.johansen@canonical.com>
Cc: Arnd Bergmann <arnd@arndb.de>,
        James Morris <james.l.morris@oracle.com>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2] apparmor: add braces around optional statement
Date: Tue, 20 Jun 2017 22:46:19 +0200
Message-Id: <20170620204722.910610-1-arnd@arndb.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1825
Lines: 54

We get a warning when AA_BUG() compiles to an nothing:

security/apparmor/label.c: In function '__label_update':
security/apparmor/label.c:2055:3: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]

There are two things we can do about this:

- add the missing braces in the call site, which also
  brings the code in line with the regular Linux coding style

- redefine the macro so it is not empty but instead uses
  no_printk() in AA_BUG_FMT() to perform format checking.

Both seem like good ideas, so this does both at once.

Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
--
v2: actually include the second part of the patch
---
 security/apparmor/include/lib.h | 2 +-
 security/apparmor/label.c       | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/security/apparmor/include/lib.h b/security/apparmor/include/lib.h
index 436b3a722357..cbfb71c1ec88 100644
--- a/security/apparmor/include/lib.h
+++ b/security/apparmor/include/lib.h
@@ -50,7 +50,7 @@
 #define AA_BUG_FMT(X, fmt, args...)					\
 	WARN((X), "AppArmor WARN %s: (" #X "): " fmt, __func__, ##args)
 #else
-#define AA_BUG_FMT(X, fmt, args...)
+#define AA_BUG_FMT(X, fmt, args...) no_printk("%s" fmt, __func__, ##args)
 #endif
 
 #define AA_ERROR(fmt, args...)						\
diff --git a/security/apparmor/label.c b/security/apparmor/label.c
index e052eaba1cf6..f8e08d94a8a6 100644
--- a/security/apparmor/label.c
+++ b/security/apparmor/label.c
@@ -2051,8 +2051,9 @@ static struct aa_label *__label_update(struct aa_label *label)
 			write_lock_irqsave(&ls->lock, flags);
 			goto remove;
 		}
-	} else
+	} else {
 		AA_BUG(labels_ns(label) != labels_ns(new));
+	}
 
 	tmp = __label_insert(labels_set(label), new, true);
 remove:
-- 
2.9.0