[PATCH 3/5] switchtec: A temporary variable should be used for the flags of switchtec_ioctl_event_ctl

Wesley Sheng
2018-11-15T03:16:28Z

From: Joey Zhang <joey.zhang@microchip.com>

For nr_idxs is larger than 1 switchtec_ioctl_event_ctl event flags will be
used by each event indexes. In current implementation the event flags are
overwritten by first call of the function event_ctl().

Preserve the event flag value with a temporary variable.

Fixes: 52eabba5bcdb ("switchtec: Add IOCTLs to the Switchtec driver")
Signed-off-by: Joey Zhang <joey.zhang@microchip.com>
Signed-off-by: Wesley Sheng <wesley.sheng@microchip.com>
---
drivers/pci/switch/switchtec.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index 480107e..a908670 100644
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -796,6 +796,7 @@ static int ioctl_event_ctl(struct switchtec_dev *stdev,
{
int ret;
int nr_idxs;
+ unsigned int event_flags;
struct switchtec_ioctl_event_ctl ctl;

if (copy_from_user(&ctl, uctl, sizeof(ctl)))
@@ -817,7 +818,9 @@ static int ioctl_event_ctl(struct switchtec_dev *stdev,
else
return -EINVAL;

+ event_flags = ctl.flags;
for (ctl.index = 0; ctl.index < nr_idxs; ctl.index++) {
+ ctl.flags = event_flags;
ret = event_ctl(stdev, &ctl);
if (ret < 0)
return ret;
--
2.7.4