media: msp3400: Avoid possible out-of-bounds array accesses in msp3400c_thread()

commit d2bceb2e20e783d57e739c71e4e50b4b9f4a3953 upstream.

It's possible for max1 to remain -1 if msp_read() always fail. This
variable is further used as index for accessing arrays.

Fix that by checking max1 prior to array accesses.

It seems that restart is the preferable action in case of out-of-bounds
value.

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

Fixes: 8a4b275 ("V4L/DVB (3427): audmode and rxsubchans fixes (VIDIOC_G/S_TUNER)")
Cc: stable@vger.kernel.org
Signed-off-by: Ivan Abramov <i.abramov@mt-integration.ru>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ulrich Hecht <uli@kernel.org>

Author: Ivan Abramov

drivers/media/i2c/msp3400-kthreads.c

@@ -601,6 +601,8 @@ int msp3400c_thread(void *data)
 				"carrier2 val: %5d / %s\n", val, cd[i].name);
 		}
 
+		if (max1 < 0 || max1 > 3)
+			goto restart;
 		/* program the msp3400 according to the results */
 		state->main = msp3400c_carrier_detect_main[max1].cdo;
 		switch (max1) {