From 4dce3b375179fdd4aba2191be11ace90ef0ec6d6 Mon Sep 17 00:00:00 2001
From: Jack Wang <jinpu.wang@ionos.com>
Date: Fri, 19 Aug 2022 08:07:48 +0200
Subject: [PATCH] usb/hcd: Fix dma_map_sg error check
Git-commit: 4dce3b375179fdd4aba2191be11ace90ef0ec6d6
References: git-fixes
Patch-mainline: v6.1-rc1

dma_map_sg return 0 on error.

Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Alexey Sheplyakov <asheplyakov@basealt.ru>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Weitao Wang <WeitaoWang-oc@zhaoxin.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-usb@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20220819060801.10443-7-jinpu.wang@ionos.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/usb/core/hcd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 94b305bbd621..90dd32a24e5b 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1474,7 +1474,7 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
 						urb->sg,
 						urb->num_sgs,
 						dir);
-				if (n <= 0)
+				if (!n)
 					ret = -EAGAIN;
 				else
 					urb->transfer_flags |= URB_DMA_MAP_SG;
-- 
2.35.3