2022-12-19 02:21:50

by Li zeming

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

The pointer new adds judgment and should help with program robustness.

Signed-off-by: Li zeming <[email protected]>
---
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;
}
--
2.18.2


2022-12-19 07:18:53

by Christophe Leroy

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



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 <[email protected]>
> ---
> 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;
> }

2024-03-13 13:30:55

by Michael Ellerman

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

On Mon, 19 Dec 2022 10:18:16 +0800, Li zeming wrote:
> The pointer new adds judgment and should help with program robustness.
>
>

Applied to powerpc/next.

[1/1] boot: simple_alloc: check after increasing memory allocation
https://git.kernel.org/powerpc/c/69b0194ccec033c208b071e019032c1919c2822d

cheers