From: Gustavo A. R. Silva <gustavo@embeddedor.com>
Date: Fri, 8 Mar 2019 00:30:26 +0000 (-0800)
Subject: ipc/sem.c: replace kvmalloc/memset with kvzalloc and use struct_size
X-Git-Tag: v5.4-rc1~1483^2~18
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4a2ae92993be24ba727faa733e99d7980d389ec0;p=platform%2Fkernel%2Flinux-rpi.git

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

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.

Link: http://lkml.kernel.org/r/20190131214221.GA28930@embeddedor
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/ipc/sem.c b/ipc/sem.c
index a188d1b0..7da4504 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;
 }