On 10/27/20 1:17 PM, Bartosz Golaszewski wrote:
From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
When allocating an array of elements, users should check for
multiplication overflow or preferably use one of the provided helpers
like: kmalloc_array().
There's no krealloc_array() counterpart but there are many users who use
regular krealloc() to reallocate arrays. Let's provide an actual
krealloc_array() implementation.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
Makes sense.
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
---
include/linux/slab.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/include/linux/slab.h b/include/linux/slab.h
index dd6897f62010..0e6683affee7 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -592,6 +592,17 @@ static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
return __kmalloc(bytes, flags);
}
+static __must_check inline void *
+krealloc_array(void *p, size_t new_n, size_t new_size, gfp_t flags)
+{
+ size_t bytes;
+
+ if (unlikely(check_mul_overflow(new_n, new_size, &bytes)))
+ return NULL;
+
+ return krealloc(p, bytes, flags);
+}
+
/**
* kcalloc - allocate memory for an array. The memory is set to zero.
* @n: number of elements.
