From 54a4b2b45817ea2365b40c923c098a26af0c0dbb Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Mon, 9 Oct 2017 14:26:27 +0200
Subject: [PATCH] ALSA: line6: Fix NULL dereference at podhd_disconnect()
Git-commit: 54a4b2b45817ea2365b40c923c098a26af0c0dbb
Patch-mainline: v4.14-rc5
References: bsc#1052235
When podhd_init() failed with the acquiring a ctrl i/f, the line6
helper still calls the disconnect callback that eventually calls again
usb_driver_release_interface() with the NULL intf.
Put the proper NULL check before calling it for avoiding an Oops.
Fixes: fc90172ba283 ("ALSA: line6: Claim pod x3 usb data interface")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/usb/line6/podhd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -299,7 +299,8 @@ static void podhd_disconnect(struct usb_
intf = usb_ifnum_to_if(line6->usbdev,
pod->line6.properties->ctrl_if);
- usb_driver_release_interface(&podhd_driver, intf);
+ if (intf)
+ usb_driver_release_interface(&podhd_driver, intf);
}
}