From 66d1b0c0580b7f1b1850ee4423f32ac42afa2e92 Mon Sep 17 00:00:00 2001

From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>

Date: Wed, 6 Nov 2019 14:28:21 -0600

Subject: [PATCH] usb: gadget: pch_udc: fix use after free

Git-commit: 66d1b0c0580b7f1b1850ee4423f32ac42afa2e92

Patch-mainline: v5.5-rc1

References: bsc#1051510

Remove pointer dereference after free.

pci_pool_free doesn't care about contents of td.

It's just a void* for it

Addresses-coverity-id: 1091173 ("Use after free")

Cc: stable@vger.kernel.org

Acked-by: Michal Nazarewicz <mina86@mina86.com>

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Link: https://lore.kernel.org/r/20191106202821.GA20347@embeddedor

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/usb/gadget/udc/pch_udc.c | 1 -

 1 file changed, 1 deletion(-)

diff --git a/drivers/usb/gadget/udc/pch_udc.c b/drivers/usb/gadget/udc/pch_udc.c

index 265dab2bbfac..3344fb8c4181 100644

--- a/drivers/usb/gadget/udc/pch_udc.c

+++ b/drivers/usb/gadget/udc/pch_udc.c

@@ -1519,7 +1519,6 @@ static void pch_udc_free_dma_chain(struct pch_udc_dev *dev,

 		td = phys_to_virt(addr);

 		addr2 = (dma_addr_t)td->next;

 		dma_pool_free(dev->data_requests, td, addr);

-		td->next = 0x00;

 		addr = addr2;

 	}

 	req->chain_len = 1;

-- 

2.16.4