From d1eab9dec6108e68d43d869a3b6645cc1df3fa9d Mon Sep 17 00:00:00 2001
From: Stefan Wahren <stefan.wahren@i2se.com>
Date: Fri, 26 May 2017 00:26:25 +0200
Subject: [PATCH] staging: vchiq_core: Bail out in case of invalid tx_pos
Git-commit: d1eab9dec6108e68d43d869a3b6645cc1df3fa9d
Patch-mainline: v4.13-rc1
References: FATE#324827

Properly handle the error case in case of an invalid tx_pos.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c
@@ -599,8 +599,10 @@ reserve_space(VCHIQ_STATE_T *state, size
 				return NULL; /* No space available */
 		}
 
-		BUG_ON(tx_pos ==
-			(state->slot_queue_available * VCHIQ_SLOT_SIZE));
+		if (tx_pos == (state->slot_queue_available * VCHIQ_SLOT_SIZE)) {
+			pr_warn("%s: invalid tx_pos: %d\n", __func__, tx_pos);
+			return NULL;
+		}
 
 		slot_index = local->slot_queue[
 			SLOT_QUEUE_INDEX_FROM_POS(tx_pos) &