From e4a7dca5de625018b29417ecc39dc5037d9a5a36 Mon Sep 17 00:00:00 2001
From: Joey Zhang <joey.zhang@microchip.com>
Date: Mon, 10 Dec 2018 17:12:22 +0800
Subject: [PATCH] switchtec: Fix SWITCHTEC_IOCTL_EVENT_IDX_ALL flags overwrite
Git-commit: e4a7dca5de625018b29417ecc39dc5037d9a5a36
Patch-mainline: v5.0-rc1
References: bsc#1051510

In the ioctl_event_ctl() SWITCHTEC_IOCTL_EVENT_IDX_ALL case, we call
event_ctl() several times with the same "ctl" struct.  Each call clobbers
ctl.flags, which leads to the problem that we may not actually enable or
disable all events as the user requested.

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>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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 480107ecb2ab..a90867099ff8 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;
-- 
2.16.4