linux-kernel - [PATCH] mutex: fix comma placement in mutex initializers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date: Mon, 24 Jun 2024 23:35:33 +0300
From: Alexey Dobriyan <adobriyan@...il.com>
To: Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>,
	Will Deacon <will@...nel.org>, Waiman Long <longman@...hat.com>
Cc: linux-kernel@...r.kernel.org
Subject: [PATCH] mutex: fix comma placement in mutex initializers

Move the commas in initializer macros _after_ initializer itself,
so they become disentagled from each other.

C99 initializer clause starts with .identifier and ends
with optional comma.

Trailing comma in ifdeffed initializers should be mandatory,
so that following snippet works:

	__DEP_MAP_MUTEX_INITIALIZER(lockname)
	.bar = 2,

Leading comma should not exist, so that following snippet works:

	.foo = 1,
	__DEP_MAP_MUTEX_INITIALIZER(lockname)
	.bar = 2,

In other words, conditional initializers should be written as

	#ifdef CONFIG_FOO
		#define INIT_X(val)	.x = val,
	#else
		#define INIT_X(val)
	#endif

otherwise it is possible to construct an example which won't compile.

Signed-off-by: Alexey Dobriyan <adobriyan@...il.com>
---

 include/linux/mutex.h |   22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

--- a/include/linux/mutex.h
+++ b/include/linux/mutex.h
@@ -26,10 +26,10 @@ struct device;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 # define __DEP_MAP_MUTEX_INITIALIZER(lockname)			\
-		, .dep_map = {					\
+		.dep_map = {					\
 			.name = #lockname,			\
 			.wait_type_inner = LD_WAIT_SLEEP,	\
-		}
+		},
 #else
 # define __DEP_MAP_MUTEX_INITIALIZER(lockname)
 #endif
@@ -37,7 +37,7 @@ struct device;
 #ifdef CONFIG_DEBUG_MUTEXES
 
 # define __DEBUG_MUTEX_INITIALIZER(lockname)				\
-	, .magic = &lockname
+	.magic = &lockname,
 
 extern void mutex_destroy(struct mutex *lock);
 
@@ -65,12 +65,14 @@ do {									\
 	__mutex_init((mutex), #mutex, &__key);				\
 } while (0)
 
-#define __MUTEX_INITIALIZER(lockname) \
-		{ .owner = ATOMIC_LONG_INIT(0) \
-		, .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(lockname.wait_lock) \
-		, .wait_list = LIST_HEAD_INIT(lockname.wait_list) \
-		__DEBUG_MUTEX_INITIALIZER(lockname) \
-		__DEP_MAP_MUTEX_INITIALIZER(lockname) }
+#define __MUTEX_INITIALIZER(lockname)					\
+{									\
+	.owner = ATOMIC_LONG_INIT(0),					\
+	.wait_lock = __RAW_SPIN_LOCK_UNLOCKED(lockname.wait_lock),	\
+	.wait_list = LIST_HEAD_INIT(lockname.wait_list),		\
+	__DEBUG_MUTEX_INITIALIZER(lockname)				\
+	__DEP_MAP_MUTEX_INITIALIZER(lockname)				\
+}
 
 #define DEFINE_MUTEX(mutexname) \
 	struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
@@ -93,7 +95,7 @@ extern bool mutex_is_locked(struct mutex *lock);
 
 #define __MUTEX_INITIALIZER(mutexname)					\
 {									\
-	.rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex)	\
+	.rtmutex = __RT_MUTEX_BASE_INITIALIZER(mutexname.rtmutex),	\
 	__DEP_MAP_MUTEX_INITIALIZER(mutexname)				\
 }