Re: [PATCH] bpf: alloc_record_per_cpu Add null check after malloc

From: Jesper Dangaard Brouer
Date: Tue Jun 09 2020 - 02:50:35 EST


On Sat, 6 Jun 2020 19:59:48 -0400
gaurav singh <gaurav1086@xxxxxxxxx> wrote:

> Hi,
>
> The memset call is made right after malloc call. To fix this, add the null
> check right after malloc and then do memset.
>
> Please find the patch below.

The fix in your patch seem correct (although there are more places),
but the way you send/submit the patch is wrong. The patch itself also
mangle whitespaces.

You can read the guide:

https://www.kernel.org/doc/html/latest/process/submitting-patches.html
https://www.kernel.org/doc/html/latest/process/index.html

--Jesper


> Thanks and regards,
> Gaurav.
>
>
> From 552b7df0e12572737929c60478b5dca2a40f4ad9 Mon Sep 17 00:00:00 2001
> From: Gaurav Singh <gaurav1086@xxxxxxxxx>
> Date: Sat, 6 Jun 2020 19:57:48 -0400
> Subject: [PATCH] bpf: alloc_record_per_cpu Add null check after malloc
>
> Signed-off-by: Gaurav Singh <gaurav1086@xxxxxxxxx>
> ---
> samples/bpf/xdp_rxq_info_user.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/samples/bpf/xdp_rxq_info_user.c
> b/samples/bpf/xdp_rxq_info_user.c
> index 4fe47502ebed..490b07b7df78 100644
> --- a/samples/bpf/xdp_rxq_info_user.c
> +++ b/samples/bpf/xdp_rxq_info_user.c
> @@ -202,11 +202,11 @@ static struct datarec *alloc_record_per_cpu(void)
>
> size = sizeof(struct datarec) * nr_cpus;
> array = malloc(size);
> - memset(array, 0, size);
> if (!array) {
> fprintf(stderr, "Mem alloc error (nr_cpus:%u)\n", nr_cpus);
> exit(EXIT_FAIL_MEM);
> }
> + memset(array, 0, size);
> return array;
> }
>



--
Best regards,
Jesper Dangaard Brouer
MSc.CS, Principal Kernel Engineer at Red Hat
LinkedIn: http://www.linkedin.com/in/brouer