Description: usb/media/dtt200u: use-after-free in __dvb_frontend_free
References:
 https://patchwork.kernel.org/patch/10046189/
Notes:
 bwh> Introduced in 4.14-rc6 by commit ead666000a5f "media: dvb_frontend:
 bwh> only use kref after initialized".  Upstream fix probably depends on
 bwh> commit 62229de19ff2 "media: dvb-core: always call invoke_release() in
 bwh> fe_free()".
Bugs:
upstream: released (4.15-rc1) [b1cb7372fa822af6c06c8045963571d13ad6348b]
4.9-upstream-stable: N/A "Vulnerable code not present"
3.16-upstream-stable: N/A "Vulnerable code not present"
3.2-upstream-stable: N/A "Vulnerable code not present"
sid: N/A "Vulnerable code not present"
4.9-stretch-security: N/A "Vulnerable code not present"
3.16-jessie-security: N/A "Vulnerable code not present"
3.2-wheezy-security: N/A "Vulnerable code not present"