[PATCH 4.9 06/39] atm: zatm: fix memcmp casting

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ivan Bornyakov <brnkv.i1@xxxxxxxxx>

[ Upstream commit f9c6442a8f0b1dde9e755eb4ff6fa22bcce4eabc ]

memcmp() returns int, but eprom_try_esi() cast it to unsigned char. One
can lose significant bits and get 0 from non-0 value returned by the
memcmp().

Signed-off-by: Ivan Bornyakov <brnkv.i1@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/atm/zatm.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/atm/zatm.c
+++ b/drivers/atm/zatm.c
@@ -1151,8 +1151,8 @@ static void eprom_get_byte(struct zatm_d
 }
 
 
-static unsigned char eprom_try_esi(struct atm_dev *dev, unsigned short cmd,
-				   int offset, int swap)
+static int eprom_try_esi(struct atm_dev *dev, unsigned short cmd, int offset,
+			 int swap)
 {
 	unsigned char buf[ZEPROM_SIZE];
 	struct zatm_dev *zatm_dev;