patches.renesas/0121-spi-rspi-Fixes-bogus-received-byte-in-qspi_transfer_.patch

From aa695f54c79bb72710fce2a1c8dbd657afb8334d Mon Sep 17 00:00:00 2001
From: DongCV <cv-dong@jinso.co.jp>
Date: Wed, 15 Feb 2017 19:50:51 +0900
Subject: [PATCH 121/255] spi: rspi: Fixes bogus received byte in
 qspi_transfer_in()

In qspi_transfer_in(), when receiving the last n (or len) bytes of data,
one bogus byte was written in the receive buffer.
This code leads to a buffer overflow.

"jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found
at 0x03b40000: 0x1900 instead
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found
at 0x03b40004: 0x000c instead"

The error message above happens when trying to mount, unmount,
and remount a jffs2-formatted device.
This patch removed the bogus write to fixes: 3be09bec42a800d4
"spi: rspi: supports 32bytes buffer for DUAL and QUAD"

And here is Geert's comment:

"spi: rspi: Fix bogus received byte in qspi_transfer_in()
When there are less than QSPI_BUFFER_SIZE remaining bytes to be received,
qspi_transfer_in() writes one bogus byte in the receive buffer, possibly
leading to a buffer overflow.
This can be reproduced by mounting, unmounting, and remounting a
jffs2-formatted device, causing lots of warnings like:

"jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found
at 0x03b40000: 0x1900 instead"

Remove the bogus write to fix this. "

Signed-off-by: DongCV <cv-dong@jinso.co.jp>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 7264abc7000d601726aefb05189ea524ee3995ba)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
---
 drivers/spi/spi-rspi.c |    1 -
 1 file changed, 1 deletion(-)

--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -848,7 +848,6 @@ static int qspi_transfer_in(struct rspi_
 			ret = rspi_pio_transfer(rspi, NULL, rx, n);
 			if (ret < 0)
 				return ret;
-			*rx++ = ret;
 		}
 		n -= len;
 	}