Commit 60bce926 authored Nov 11, 2022 by Anastasia Belova Committed by Greg Kroah-Hartman Dec 14, 2022

HID: hid-lg4ff: Add check for empty lbuf



commit d180b6496143cd360c5d5f58ae4b9a8229c1f344 upstream.

If an empty buf is received, lbuf is also empty. So lbuf is
accessed by index -1.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: f31a2de3 ("HID: hid-lg4ff: Allow switching of Logitech gaming wheels between compatibility modes")
Signed-off-by: Anastasia Belova <abelova@astralinux.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 625814b8

drivers/hid/hid-lg4ff.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -872,6 +872,12 @@ static ssize_t lg4ff_alternate_modes_store(struct device *dev, struct device_att
		return -ENOMEM;

		i = strlen(lbuf);

		if (i == 0) {
		kfree(lbuf);
		return -EINVAL;
		}

		if (lbuf[i-1] == '\n') {
		if (i == 1) {
		kfree(lbuf);