Re: [PATCH] boot: simple_alloc: check after increasing memory allocation

From: Christophe Leroy
Date: Mon Dec 19 2022 - 01:44:22 EST




Le 19/12/2022 à 03:18, Li zeming a écrit :
> The pointer new adds judgment and should help with program robustness.

This text is not understandable.

Do you mean:

simple_malloc() will return NULL when there is now enough memory left.
Check pointer 'new' before using it to copy the old data.

>
> Signed-off-by: Li zeming <zeming@xxxxxxxxxxxx>
> ---
> arch/powerpc/boot/simple_alloc.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/boot/simple_alloc.c b/arch/powerpc/boot/simple_alloc.c
> index 267d6524caac..db9aaa5face3 100644
> --- a/arch/powerpc/boot/simple_alloc.c
> +++ b/arch/powerpc/boot/simple_alloc.c
> @@ -112,7 +112,9 @@ static void *simple_realloc(void *ptr, unsigned long size)
> return ptr;
>
> new = simple_malloc(size);
> - memcpy(new, ptr, p->size);
> + if (new)
> + memcpy(new, ptr, p->size);
> +
> simple_free(ptr);
> return new;
> }