[PATCH] lib/test_kasan.c: Fix memory leak in kmalloc_oob_krealloc_more()

[PATCH] lib/test_kasan.c: Fix memory leak in kmalloc_oob_krealloc_more()

[Gustavo A. R. Silva]

In case memory resources for _ptr2_ were allocated, release them
before return.

Notice that in case _ptr1_ happens to be NULL, krealloc() behaves
exactly like kmalloc().

Addresses-Coverity-ID: 1490594 ("Resource leak")
Fixes: 3f15801cdc23 ("lib: add kasan test module")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 lib/test_kasan.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 328d33beae36..3872d250ed2c 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -158,6 +158,7 @@ static noinline void __init kmalloc_oob_krealloc_more(void)
 	if (!ptr1 || !ptr2) {
 		pr_err("Allocation failed\n");
 		kfree(ptr1);
+		kfree(ptr2);
 		return;
 	}
 
-- 
2.25.0

Re: [PATCH] lib/test_kasan.c: Fix memory leak in kmalloc_oob_krealloc_more()

[Dmitry Vyukov]

On Thu, Jan 23, 2020 at 4:59 PM Gustavo A. R. Silva
<gustavo@embeddedor.com> wrote:
>
> In case memory resources for _ptr2_ were allocated, release them
> before return.
>
> Notice that in case _ptr1_ happens to be NULL, krealloc() behaves
> exactly like kmalloc().

Reviewed-by: Dmitry Vyukov <dvyukov@google.com>

The scenario where ptr1 is NULL, but ptr2 is not NULL is not impossible indeed.

> Addresses-Coverity-ID: 1490594 ("Resource leak")
> Fixes: 3f15801cdc23 ("lib: add kasan test module")
> Cc: stable@vger.kernel.org
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> ---
>  lib/test_kasan.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/lib/test_kasan.c b/lib/test_kasan.c
> index 328d33beae36..3872d250ed2c 100644
> --- a/lib/test_kasan.c
> +++ b/lib/test_kasan.c
> @@ -158,6 +158,7 @@ static noinline void __init kmalloc_oob_krealloc_more(void)
>         if (!ptr1 || !ptr2) {
>                 pr_err("Allocation failed\n");
>                 kfree(ptr1);
> +               kfree(ptr2);
>                 return;
>         }
>
> --
> 2.25.0
>