[PATCH 02/10] wifi: rtw88: fix incorrect error codes in rtw_debugfs_set_read_reg

[Zhang Shurong]

If there is a failure during copy_from_user or user-provided data
buffer is invalid, rtw_debugfs_set_read_reg should return negative
error code instead of a positive value count.

Fix this bug by returning correct error code.

Signed-off-by: Zhang Shurong <zhang_shurong@xxxxxxxxxxx>
---
 drivers/net/wireless/realtek/rtw88/debug.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/debug.c b/drivers/net/wireless/realtek/rtw88/debug.c
index bc41c5a7acaf..3c3350bb2855 100644
--- a/drivers/net/wireless/realtek/rtw88/debug.c
+++ b/drivers/net/wireless/realtek/rtw88/debug.c
@@ -201,13 +201,16 @@ static ssize_t rtw_debugfs_set_read_reg(struct file *filp,
 	char tmp[32 + 1];
 	u32 addr, len;
 	int num;
+	int ret;
 
-	rtw_debugfs_copy_from_user(tmp, sizeof(tmp), buffer, count, 2);
+	ret = rtw_debugfs_copy_from_user(tmp, sizeof(tmp), buffer, count, 2);
+	if (ret < 0)
+		return ret;
 
 	num = sscanf(tmp, "%x %x", &addr, &len);
 
 	if (num !=  2)
-		return count;
+		return -EINVAL;
 
 	if (len != 1 && len != 2 && len != 4) {
 		rtw_warn(rtwdev, "read reg setting wrong len\n");
-- 
2.40.0