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Date: Thu, 28 Aug 2025 20:18:43 +0100
From: Simon Horman <horms@kernel.org>
To: Miaoqian Lin <linmq006@gmail.com>
Cc: Karsten Keil <isdn@linux-pingi.de>, Laura Abbott <labbott@redhat.com>,
	"David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mISDN: Fix memory leak in dsp_hwec_enable()
Message-ID: <20250828191843.GH31759@horms.kernel.org>
References: <20250828081457.36061-1-linmq006@gmail.com>
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In-Reply-To: <20250828081457.36061-1-linmq006@gmail.com>

On Thu, Aug 28, 2025 at 04:14:57PM +0800, Miaoqian Lin wrote:
> dsp_hwec_enable() allocates dup pointer by kstrdup(arg),
> but then it updates dup variable by strsep(&dup, ",").
> As a result when it calls kfree(dup), the dup variable may be
> a modified pointer that no longer points to the original allocated
> memory, causing a memory leak.
> 
> The issue is the same pattern as fixed in commit c6a502c22999
> ("mISDN: Fix memory leak in dsp_pipeline_build()").

Thanks for noting this, it was quite helpful to me.

> 
> Fixes: 9a4381618262 ("mISDN: Remove VLAs")
> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>

Reviewed-by: Simon Horman <horms@kernel.org>