From 2cc12751cf464a722ff57b54d17d30c84553f9c0 Mon Sep 17 00:00:00 2001
From: Aditya Pakki <pakki001@umn.edu>
Date: Wed, 20 Mar 2019 10:57:54 -0500
Subject: [PATCH] thunderbolt: Fix to check for kmemdup failure
Git-commit: 2cc12751cf464a722ff57b54d17d30c84553f9c0
Patch-mainline: v5.2-rc1
References: bsc#1051510

Memory allocated via kmemdup might fail and return a NULL pointer.
This patch adds a check on the return value of kmemdup and passes the
error upstream.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/thunderbolt/switch.c |   22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -1205,13 +1205,14 @@ int tb_switch_configure(struct tb_switch
 	return tb_plug_events_active(sw, true);
 }
 
-static void tb_switch_set_uuid(struct tb_switch *sw)
+static int tb_switch_set_uuid(struct tb_switch *sw)
 {
 	u32 uuid[4];
-	int cap;
+	int cap, ret;
 
+	ret = 0;
 	if (sw->uuid)
-		return;
+		return ret;
 
 	/*
 	 * The newer controllers include fused UUID as part of link
@@ -1219,7 +1220,9 @@ static void tb_switch_set_uuid(struct tb
 	 */
 	cap = tb_switch_find_vse_cap(sw, TB_VSE_CAP_LINK_CONTROLLER);
 	if (cap > 0) {
-		tb_sw_read(sw, uuid, TB_CFG_SWITCH, cap + 3, 4);
+		ret = tb_sw_read(sw, uuid, TB_CFG_SWITCH, cap + 3, 4);
+		if (ret)
+			return ret;
 	} else {
 		/*
 		 * ICM generates UUID based on UID and fills the upper
@@ -1234,6 +1237,9 @@ static void tb_switch_set_uuid(struct tb
 	}
 
 	sw->uuid = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
+	if (!sw->uuid)
+		ret = -ENOMEM;
+	return ret;
 }
 
 static int tb_switch_add_dma_port(struct tb_switch *sw)
@@ -1279,7 +1285,9 @@ static int tb_switch_add_dma_port(struct
 
 	if (status) {
 		tb_sw_info(sw, "switch flash authentication failed\n");
-		tb_switch_set_uuid(sw);
+		ret = tb_switch_set_uuid(sw);
+		if (ret)
+			return ret;
 		nvm_set_auth_status(sw, status);
 	}
 
@@ -1329,7 +1337,9 @@ int tb_switch_add(struct tb_switch *sw)
 		}
 		tb_sw_info(sw, "uid: %#llx\n", sw->uid);
 
-		tb_switch_set_uuid(sw);
+		ret = tb_switch_set_uuid(sw);
+		if (ret)
+			return ret;
 
 		for (i = 0; i <= sw->config.max_port_number; i++) {
 			if (sw->ports[i].disabled) {