[PATCH] ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size

From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
To: linux-kernel@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>
Subject: [PATCH] ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size
Date: Thu, 31 Jan 2019 15:42:21 -0600	[thread overview]
Message-ID: <20190131214221.GA28930@embeddedor> (raw)

Use kvzalloc() instead of kvmalloc() and memset().

Also, make use of the struct_size() helper instead of
the open-coded version in order to avoid any potential
type mistakes.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 ipc/sem.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/ipc/sem.c b/ipc/sem.c
index a188d1b064ea..7da4504bcc7c 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -488,18 +488,14 @@ static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
 static struct sem_array *sem_alloc(size_t nsems)
 {
 	struct sem_array *sma;
-	size_t size;
 
 	if (nsems > (INT_MAX - sizeof(*sma)) / sizeof(sma->sems[0]))
 		return NULL;
 
-	size = sizeof(*sma) + nsems * sizeof(sma->sems[0]);
-	sma = kvmalloc(size, GFP_KERNEL);
+	sma = kvzalloc(struct_size(sma, sems, nsems), GFP_KERNEL);
 	if (unlikely(!sma))
 		return NULL;
 
-	memset(sma, 0, size);
-
 	return sma;
 }
 
-- 
2.20.1

