Date:   Mon, 6 Mar 2023 18:28:10 +0300
From:   Serge Semin <fancer.lancer@gmail.com>
To:     Kang Chen <void0red@gmail.com>
Cc:     jdmason@kudzu.us, dave.jiang@intel.com, allenbh@gmail.com,
        ntb@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ntb_tool: check null return of devm_kcalloc in
 tool_init_mws
Message-ID: <20230306152810.ptb622tfhoxehhdc@mobilestation>
References: <20230226055743.2522819-1-void0red@gmail.com>
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On Sun, Feb 26, 2023 at 01:57:43PM +0800, Kang Chen wrote:
> devm_kcalloc may fails, tc->peers[pidx].outmws might be null
> and will cause null pointer dereference later.
> 
> Signed-off-by: Kang Chen <void0red@gmail.com>

Please add the fixes tag:
Fixes: 7f46c8b3a552 ("NTB: ntb_tool: Add full multi-port NTB API support")
so the patch could be noticeable by the stable kernel maintainers.

Other than that looks good.
Reviewed-by: Serge Semin <fancer.lancer@gmail.com>

* Please don't forget to add the Rb-tags on v2.

-Serge(y)

> ---
>  drivers/ntb/test/ntb_tool.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/ntb/test/ntb_tool.c b/drivers/ntb/test/ntb_tool.c
> index 5ee0afa62..eeeb4b1c9 100644
> --- a/drivers/ntb/test/ntb_tool.c
> +++ b/drivers/ntb/test/ntb_tool.c
> @@ -998,6 +998,8 @@ static int tool_init_mws(struct tool_ctx *tc)
>  		tc->peers[pidx].outmws =
>  			devm_kcalloc(&tc->ntb->dev, tc->peers[pidx].outmw_cnt,
>  				   sizeof(*tc->peers[pidx].outmws), GFP_KERNEL);
> +		if (tc->peers[pidx].outmws == NULL)
> +			return -ENOMEM;
>  
>  		for (widx = 0; widx < tc->peers[pidx].outmw_cnt; widx++) {
>  			tc->peers[pidx].outmws[widx].pidx = pidx;
> -- 
> 2.34.1
> 
>