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From:   Luis Araneda <luaraneda@gmail.com>
To:     linux@armlinux.org.uk, michal.simek@xilinx.com
Cc:     stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, Luis Araneda <luaraneda@gmail.com>
Subject: [PATCH 2/2] ARM: zynq: Use memcpy_toio instead of memcpy on smp bring-up
Date:   Mon,  5 Aug 2019 23:07:18 -0400
Message-Id: <20190806030718.29048-3-luaraneda@gmail.com>
In-Reply-To: <20190806030718.29048-1-luaraneda@gmail.com>
References: <20190806030718.29048-1-luaraneda@gmail.com>
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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);
 
-- 
2.22.0