[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <1473326296-23987-2-git-send-email-harish_kandiga@mentor.com>
Date: Thu, 8 Sep 2016 11:18:16 +0200
From: Harish Jenny K N <harish_kandiga@...tor.com>
To: Felipe Balbi <balbi@...nel.org>
CC: <linux-usb@...r.kernel.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
<linux-kernel@...r.kernel.org>, Jim Baxter <jim_baxter@...tor.com>
Subject: [PATCH v1 1/1] usb: gadget: f_fs: Stop ffs_closed NULL pointers.
From: Jim Baxter <jim_baxter@...tor.com>
The struct ffs_data::private_data has a pointer to
ffs_dev stored in it during the ffs_fs_mount() function
however it is not cleared when the ffs_dev is freed
later which causes the ffs_closed function to crash
with "Unable to handle kernel NULL pointer dereference"
error when using the data in ffs_data::private_data.
This clears this pointer during the ffs_free_dev clean
up function.
Signed-off-by: Jim Baxter <jim_baxter@...tor.com>
Signed-off-by: Jiada Wang <jiada_wang@...tor.com>
Signed-off-by: Harish Jenny K N <harish_kandiga@...tor.com>
---
drivers/usb/gadget/function/f_fs.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 5c8429f..b309650 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -3470,6 +3470,11 @@ static void _ffs_free_dev(struct ffs_dev *dev)
list_del(&dev->entry);
if (dev->name_allocated)
kfree(dev->name);
+
+ /* Clear the private_data pointer to stop incorrect dev access */
+ if (dev->ffs_data)
+ dev->ffs_data->private_data = NULL;
+
kfree(dev);
if (list_empty(&ffs_devices))
functionfs_cleanup();
--
1.7.9.5
Powered by blists - more mailing lists