[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20180601004233.37822-8-keescook@chromium.org>
Date: Thu, 31 May 2018 17:42:24 -0700
From: Kees Cook <keescook@...omium.org>
To: Matthew Wilcox <mawilcox@...rosoft.com>
Cc: Kees Cook <keescook@...omium.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Rasmus Villemoes <linux@...musvillemoes.dk>,
Matthew Wilcox <willy@...radead.org>,
LKML <linux-kernel@...r.kernel.org>,
Linux-MM <linux-mm@...ck.org>,
Kernel Hardening <kernel-hardening@...ts.openwall.com>
Subject: [PATCH v3 07/16] mm: Use overflow helpers in kvmalloc()
Instead of open-coded multiplication and bounds checking, use the new
overflow helper. Additionally prepare for vmalloc() users to add
array_size()-family helpers in the future.
Signed-off-by: Kees Cook <keescook@...omium.org>
---
include/linux/mm.h | 7 +++++--
include/linux/vmalloc.h | 1 +
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 1ac1f06a4be6..7cb1c6a6bf82 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -25,6 +25,7 @@
#include <linux/err.h>
#include <linux/page_ref.h>
#include <linux/memremap.h>
+#include <linux/overflow.h>
struct mempolicy;
struct anon_vma;
@@ -560,10 +561,12 @@ static inline void *kvzalloc(size_t size, gfp_t flags)
static inline void *kvmalloc_array(size_t n, size_t size, gfp_t flags)
{
- if (size != 0 && n > SIZE_MAX / size)
+ size_t bytes;
+
+ if (unlikely(check_mul_overflow(n, size, &bytes)))
return NULL;
- return kvmalloc(n * size, flags);
+ return kvmalloc(bytes, flags);
}
extern void kvfree(const void *addr);
diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h
index 1e5d8c392f15..398e9c95cd61 100644
--- a/include/linux/vmalloc.h
+++ b/include/linux/vmalloc.h
@@ -8,6 +8,7 @@
#include <linux/llist.h>
#include <asm/page.h> /* pgprot_t */
#include <linux/rbtree.h>
+#include <linux/overflow.h>
struct vm_area_struct; /* vma defining user mapping in mm_types.h */
struct notifier_block; /* in notifier.h */
--
2.17.0
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
