lkml.org 
[lkml]   [2016]   [Nov]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [v4.9-rc4] dvb-usb/cinergyT2 NULL pointer dereference
On Sun, Nov 6, 2016 at 7:40 AM, Jörg Otte <jrg.otte@gmail.com> wrote:
> Since v4.9-rc4 I get following crash in dvb-usb-cinergyT2 module.

Looks like it's commit 5ef8ed0e5608f ("[media] cinergyT2-core: don't
do DMA on stack"), which movced the DMA data array from the stack to
the "private" pointer. In the process it also added serialization in
the form of "data_mutex", but and now it oopses on that mutex because
the private pointer is NULL.

It looks like the "->private" pointer is allocated in dvb_usb_adapter_init()

cinergyt2_usb_probe ->
dvb_usb_device_init ->
dvb_usb_init() ->
dvb_usb_adapter_init()

but the dvb_usb_init() function calls dvb_usb_device_power_ctrl()
(which calls the "power_ctrl" function, which is
cinergyt2_power_ctrl() for that drive) *before* it initializes the
private field.

Mauro, Patrick, could dvb_usb_adapter_init() be called earlier, perhaps?

Linus

\
 
 \ /
  Last update: 2016-11-08 19:43    [W:0.172 / U:0.160 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site