Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Received-SPF: Pass (protection.outlook.com: domain of xilinx.com designates
 149.199.60.83 as permitted sender) receiver=protection.outlook.com;
 client-ip=149.199.60.83; helo=xsj-pvapsmtpgw01;
Subject: Re: [PATCH 2/2] ARM: zynq: Use memcpy_toio instead of memcpy on smp
 bring-up
To:     Luis Araneda <luaraneda@gmail.com>, linux@armlinux.org.uk,
        michal.simek@xilinx.com
Cc:     stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
References: <20190806030718.29048-1-luaraneda@gmail.com>
 <20190806030718.29048-3-luaraneda@gmail.com>
From:   Michal Simek <michal.simek@xilinx.com>
Message-ID: <194fe121-151d-0b64-b83e-e4d82c02efa7@xilinx.com>
Date:   Tue, 6 Aug 2019 08:41:55 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <20190806030718.29048-3-luaraneda@gmail.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Aug 2019 06:42:14.6199
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: b06e1766-e689-4ee1-635b-08d71a3937e3
X-MS-Exchange-CrossTenant-Id: 657af505-d5df-48d0-8300-c31994686c5c
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=657af505-d5df-48d0-8300-c31994686c5c;Ip=[149.199.60.83];Helo=[xsj-pvapsmtpgw01]
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW2PR02MB3690
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 06. 08. 19 5:07, Luis Araneda wrote:
> This fixes a kernel panic (read overflow) on memcpy when
> FORTIFY_SOURCE is enabled.
> 
> The computed size of memcpy args are:
> - p_size (dst): 4294967295 = (size_t) -1
> - q_size (src): 1
> - size (len): 8
> 
> Additionally, the memory is marked as __iomem, so one of
> the memcpy_* functions should be used for read/write
> 
> Signed-off-by: Luis Araneda <luaraneda@gmail.com>
> ---
>  arch/arm/mach-zynq/platsmp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-zynq/platsmp.c b/arch/arm/mach-zynq/platsmp.c
> index 38728badabd4..a10085be9073 100644
> --- a/arch/arm/mach-zynq/platsmp.c
> +++ b/arch/arm/mach-zynq/platsmp.c
> @@ -57,7 +57,7 @@ int zynq_cpun_start(u32 address, int cpu)
>  			* 0x4: Jump by mov instruction
>  			* 0x8: Jumping address
>  			*/
> -			memcpy((__force void *)zero, &zynq_secondary_trampoline,
> +			memcpy_toio(zero, &zynq_secondary_trampoline,
>  							trampoline_size);
>  			writel(address, zero + trampoline_size);
>  

I would consider this one as stable material. Please also add there link
to the patch which this patch fixes.

M