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Subject: Re: [PATCH] um: vector: Avoid NULL ptr deference if transport is
 unset
To:     Sjoerd Simons <sjoerd.simons@collabora.co.uk>,
        linux-um@lists.infradead.org
Cc:     Jeff Dike <jdike@addtoit.com>, Richard Weinberger <richard@nod.at>,
        linux-kernel@vger.kernel.org
References: <20200216213624.800463-1-sjoerd.simons@collabora.co.uk>
From:   Anton Ivanov <anton.ivanov@cambridgegreys.com>
Organization: Cambridge Greys
Message-ID: <74c04f11-4b67-d1a7-7d05-197a229b245c@cambridgegreys.com>
Date:   Mon, 17 Feb 2020 07:53:50 +0000
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On 16/02/2020 21:36, Sjoerd Simons wrote:
> When the transport option of a vec isn't set strncmp ends up being
> called on a NULL pointer. Better not do that.
> 
> Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
> 
> ---
> 
>   arch/um/drivers/vector_kern.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
> index 0ff86391f77d..ca90666c0b61 100644
> --- a/arch/um/drivers/vector_kern.c
> +++ b/arch/um/drivers/vector_kern.c
> @@ -198,6 +198,9 @@ static int get_transport_options(struct arglist *def)
>   	long parsed;
>   	int result = 0;
>   
> +	if (transport == NULL)
> +		return -EINVAL;
> +
>   	if (vector != NULL) {
>   		if (kstrtoul(vector, 10, &parsed) == 0) {
>   			if (parsed == 0) {
> 
Acked-By: Anton Ivanov <anton.ivanov@cambridgegreys.com>

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Anton R. Ivanov
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