original_kernel/drivers/media/dvb/dvb-core
Laurent Pinchart f41ced8f10 Check fops_get() return value
Several subsystem open handlers dereference the fops_get() return value
without checking it for nullness.  This opens a race condition between the
open handler and module unloading.

A module can be marked as being unloaded (MODULE_STATE_GOING) before its
exit function is called and gets the chance to unregister the driver.
During that window open handlers can still be called, and fops_get() will
fail in try_module_get() and return a NULL pointer.

This change checks the fops_get() return value and returns -ENODEV if NULL.

Reported-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Acked-by: Takashi Iwai <tiwai@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Airlie <airlied@linux.ie>
Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06 15:59:11 -08:00
..
Makefile
demux.h
dmxdev.c
dmxdev.h
dvb_ca_en50221.c
dvb_ca_en50221.h
dvb_demux.c
dvb_demux.h
dvb_filter.c
dvb_filter.h
dvb_frontend.c V4L/DVB (9916): dvb-core: don't add an event when in ONE SHOT mode for algo type HW 2008-12-30 09:39:16 -02:00
dvb_frontend.h
dvb_math.c
dvb_math.h
dvb_net.c
dvb_net.h
dvb_ringbuffer.c
dvb_ringbuffer.h
dvbdev.c Check fops_get() return value 2009-01-06 15:59:11 -08:00
dvbdev.h V4L/DVB (9361): Dynamic DVB minor allocation 2008-12-29 17:53:12 -02:00