From: Matthias Reichl <hias@horus.com>
Date: Fri, 27 Mar 2020 15:03:50 +0000 (+0100)
Subject: USB: cdc-acm: restore capability check order
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=4826a0bef66e71ecdf78c9748375932f5c2073cc;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

USB: cdc-acm: restore capability check order

commit 62d65bdd9d05158aa2547f8ef72375535f3bc6e3 upstream.

commit b401f8c4f492c ("USB: cdc-acm: fix rounding error in TIOCSSERIAL")
introduced a regression by changing the order of capability and close
settings change checks. When running with CAP_SYS_ADMIN setting the
close settings to the values already set resulted in -EOPNOTSUPP.

Fix this by changing the check order back to how it was before.

Fixes: b401f8c4f492c ("USB: cdc-acm: fix rounding error in TIOCSSERIAL")
Cc: Anthony Mallet <anthony.mallet@laas.fr>
Cc: stable <stable@vger.kernel.org>
Cc: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Matthias Reichl <hias@horus.com>
Link: https://lore.kernel.org/r/20200327150350.3657-1-hias@horus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 13df3c8cd7bf..5b0bffba4aac 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -863,16 +863,16 @@ static int set_serial_info(struct acm *acm,
 
 	mutex_lock(&acm->port.mutex);
 
-	if ((new_serial.close_delay != old_close_delay) ||
-            (new_serial.closing_wait != old_closing_wait)) {
-		if (!capable(CAP_SYS_ADMIN))
+	if (!capable(CAP_SYS_ADMIN)) {
+		if ((new_serial.close_delay != old_close_delay) ||
+	            (new_serial.closing_wait != old_closing_wait))
 			retval = -EPERM;
-		else {
-			acm->port.close_delay  = close_delay;
-			acm->port.closing_wait = closing_wait;
-		}
-	} else
-		retval = -EOPNOTSUPP;
+		else
+			retval = -EOPNOTSUPP;
+	} else {
+		acm->port.close_delay  = close_delay;
+		acm->port.closing_wait = closing_wait;
+	}
 
 	mutex_unlock(&acm->port.mutex);
 	return retval;