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| author | Oliver Neukum <oneukum@suse.com> | 2018-01-08 17:21:07 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-08 15:26:31 +0300 |
| commit | 1f17d5033fe3c435556d8fb731f3a51ca073ce85 (patch) | |
| tree | 7a7d198d8211debacd2441c6601e83d25391d91e /drivers/media | |
| parent | 5f834dd24baec1f9926e8a06609e0906fd607b06 (diff) | |
| download | linux-1f17d5033fe3c435556d8fb731f3a51ca073ce85.tar.xz | |
media: usbtv: prevent double free in error case
commit 50e7044535537b2a54c7ab798cd34c7f6d900bd2 upstream.
Quoting the original report:
It looks like there is a double-free vulnerability in Linux usbtv driver
on an error path of usbtv_probe function. When audio registration fails,
usbtv_video_free function ends up freeing usbtv data structure, which
gets freed the second time under usbtv_video_fail label.
usbtv_audio_fail:
usbtv_video_free(usbtv); =>
v4l2_device_put(&usbtv->v4l2_dev);
=> v4l2_device_put
=> kref_put
=> v4l2_device_release
=> usbtv_release (CALLBACK)
=> kfree(usbtv) (1st time)
usbtv_video_fail:
usb_set_intfdata(intf, NULL);
usb_put_dev(usbtv->udev);
kfree(usbtv); (2nd time)
So, as we have refcounting, use it
Reported-by: Yavuz, Tuba <tuba@ece.ufl.edu>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/usb/usbtv/usbtv-core.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/media/usb/usbtv/usbtv-core.c b/drivers/media/usb/usbtv/usbtv-core.c index 71fb5734995b..68df16b3ce72 100644 --- a/drivers/media/usb/usbtv/usbtv-core.c +++ b/drivers/media/usb/usbtv/usbtv-core.c @@ -112,6 +112,8 @@ static int usbtv_probe(struct usb_interface *intf, return 0; usbtv_audio_fail: + /* we must not free at this point */ + usb_get_dev(usbtv->udev); usbtv_video_free(usbtv); usbtv_video_fail: |