Linux-USB Archive on
 help / color / Atom feed
From: "Gustavo A. R. Silva" <>
To: Felipe Balbi <>,
	Greg Kroah-Hartman <>,
	Michal Nazarewicz <>,
	Andy Shevchenko <>
	"Gustavo A. R. Silva" <>
Subject: [PATCH v4] usb: gadget: pch_udc: fix use after free
Date: Wed, 6 Nov 2019 14:28:21 -0600
Message-ID: <20191106202821.GA20347@embeddedor> (raw)

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")
Acked-by: Michal Nazarewicz <>
Signed-off-by: Gustavo A. R. Silva <>
Changes in v4:
  Fix line-wrapping.
  Update commit log.
  Update subject line.

Changes in v3:
  Remove 'td->next = 0x00' inside for loop.
  Remove unnecessary pointer nullification after free.

Changes in v2:
  Move pointer dereference before pci_pool_free()
  Set pointer to NULL after free

 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;

                 reply index

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20191106202821.GA20347@embeddedor \ \ \ \ \ \ \ \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-USB Archive on

Archives are clonable:
	git clone --mirror linux-usb/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-usb linux-usb/ \
	public-inbox-index linux-usb

Example config snippet for mirrors

Newsgroup available over NNTP:

AGPL code for this site: git clone