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Message-ID: <eaedf019-349c-c686-0f23-093371b4b61f@cambridgegreys.com>
Date:   Tue, 3 Jan 2023 10:28:41 +0000
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Subject: Re: [PATCH] um: vector: Fix memory leak in vector_config
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To:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Miaoqian Lin <linmq006@gmail.com>
Cc:     Richard Weinberger <richard@nod.at>,
        Johannes Berg <johannes@sipsolutions.net>,
        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Wolfram Sang <wsa+renesas@sang-engineering.com>,
        linux-um@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20221229075323.1394010-1-linmq006@gmail.com>
 <CAMuHMdWFyKA7nUojivvTwWcmxaiUQifRRB=Kn1q-qzmn20Xkuw@mail.gmail.com>
From:   Anton Ivanov <anton.ivanov@cambridgegreys.com>
In-Reply-To: <CAMuHMdWFyKA7nUojivvTwWcmxaiUQifRRB=Kn1q-qzmn20Xkuw@mail.gmail.com>
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On 03/01/2023 08:00, Geert Uytterhoeven wrote:
> Hi Miaoqian,
>
> On Thu, Dec 29, 2022 at 8:53 AM Miaoqian Lin <linmq006@gmail.com> wrote:
>> kstrdup() return newly allocated copy of the string.
>> Call kfree() to release the memory when after use.
>>
>> Fixes: 49da7e64f33e ("High Performance UML Vector Network Driver")
>> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
> Thanks for your patch!
>
>> --- a/arch/um/drivers/vector_kern.c
>> +++ b/arch/um/drivers/vector_kern.c
>> @@ -765,6 +765,7 @@ static int vector_config(char *str, char **error_out)
>>
>>          parsed = uml_parse_vector_ifspec(params);
>>
>> +       kfree(params);
> Are you sure the memory pointed to by "params" is no longer used?
> "parsed" seems to contain pointers pointing to (parts of) the string
> pointed to by "params", so it cannot be freed.

+1.

I was just about to send the same comment.

>
>>          if (parsed == NULL) {
>>                  *error_out = "vector_config failed to parse parameters";
>>                  return -EINVAL;
> Gr{oetje,eeting}s,
>
>                          Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                  -- Linus Torvalds
>
-- 
Anton R. Ivanov
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