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Date: Mon, 1 Apr 2024 12:09:42 -0700
From: Alison Schofield <alison.schofield@intel.com>
To: Kwangjin Ko <kwangjin.ko@sk.com>
Cc: dave@stgolabs.net, jonathan.cameron@huawei.com, dave.jiang@intel.com,
	vishal.l.verma@intel.com, ira.weiny@intel.com,
	dan.j.williams@intel.com, linux-cxl@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel_team@skhynix.com
Subject: Re: [PATCH 2/2] cxl/core: Fix incorrect array index in
 cxl_clear_event_record()
Message-ID: <ZgsGdvUfp8uz2xgb@aschofie-mobl2>
References: <20240401091057.1044-1-kwangjin.ko@sk.com>
 <20240401091057.1044-2-kwangjin.ko@sk.com>
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In-Reply-To: <20240401091057.1044-2-kwangjin.ko@sk.com>

On Mon, Apr 01, 2024 at 06:10:56PM +0900, Kwangjin Ko wrote:
> The variable 'i' should be incremented after dev_dbg(), or print
> gen->hdr.handle instead. Otherwise, the handle value of the next loop
> will be printed. Furthermore, in the final loop, accessing 'handles[i]'
> will cause a buffer overflow.

This fix is already queued:
https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/?h=fixes

> 
> Signed-off-by: Kwangjin Ko <kwangjin.ko@sk.com>
> ---
>  drivers/cxl/core/mbox.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index a38531a055c8..84014aa01c95 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -913,9 +913,9 @@ static int cxl_clear_event_record(struct cxl_memdev_state *mds,
>  		struct cxl_event_record_raw *raw = &get_pl->records[cnt];
>  		struct cxl_event_generic *gen = &raw->event.generic;
>  
> -		payload->handles[i++] = gen->hdr.handle;
>  		dev_dbg(mds->cxlds.dev, "Event log '%d': Clearing %u\n", log,
> -			le16_to_cpu(payload->handles[i]));
> +			le16_to_cpu(gen->hdr.handle));
> +		payload->handles[i++] = gen->hdr.handle;
>  
>  		if (i == max_handles) {
>  			payload->nr_recs = i;
> -- 
> 2.34.1
>